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Covering the functional and esthetic needs of edentulous patients, Prosthodontic Treatment for Edentulous Patients: Complete Dentures and Implant-Supported Prostheses, 13th Edition helps you provide complete dentures, with and without dental implant support. It addresses both the behavioral and clinical aspects of diagnosis and treatment and covers treatment modalities including osseointegration, overdentures, implant-supported fixed prosthesis, and the current and future directions of implant prosthodontics.
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- Höfundur: George Zarb
- Útgáfa:13
- Útgáfudagur: 012012
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- Format:ePub
- ISBN 13: 9780323078443
- ISBN 10: 0323078443
Efnisyfirlit
- Front Matter
- Dedication
- Contributors
- Preface
- Acknowledgments
- Part I The Patient
- Chapter 1 The Edentulous State
- Historical Context and Current Considerations
- Figure 1-1 A to D, Characteristic facial and circumoral changes associated with a dentate young woman in her 20s. Parts A to D are in stark contrast with those observed in an aging woman who has been wearing dentures for several decades (E to H). The denture's three surfaces (G)—intaglio or fitting, polished, and occlusal—were established separately by the dentist. They were integrated to replace the missing teeth and the severely reduced supporting tissues as an integral part of routine prosthodontic protocol. Optimal esthetic support combined with adequate renewed function usually can be achieved for most edentulous patients with complete dentures.
- Biomechanical Support for the Natural Dentition
- Figure 1-2 Four patients representing different age groups (50 years and older). The pretreatment (A, C, E, and G) and posttreatment (B, D, F, and H) pictures reflect the sort of esthetic clues or decisions routinely used by dentists in complete denture prosthodontics to improve their edentulous patients’ natural smile.
- Figure 1-3 The transition from a dentate to an edentulous state requires an understanding of the entirely different support mechanisms available for natural teeth and complete dentures. The natural dentition (A and B) is supported and retained via an area of 45 cm2 of periodontal ligament. This attachment mechanism, which evolved quantitatively and qualitatively for its specialized role, is substituted for by a compromised one when a patient becomes progressively more edentulous both in the maxilla (C to E) and mandible (F to H).
- Biomechanical Support Mechanisms for Complete Dentures
- TABLE 1-1 CALCULATION OF TOTAL TIME DURING 24 HOURS WHEN DIRECT FUNCTIONAL OCCLUSAL FORCE IS APPLIED TO THE PERIODONTAL TISSUES
- Mucosal Support and Masticatory Loads
- The Residual Ridges
- Natural and Prosthetic Dental Occlusion: Functional and Parafunctional Considerations
- Figure 1-4 A, The overall reduction of the edentulous residual alveolar ridges. The a refers to bone height following extractions, while the b shows the bone level several years later. B, The bone reduction may be generalized or uneven but appears to be inevitable and variable. C to H illustrate the range of clinical and radiographic changes seen in two different edentulous mouths. Note that potential denture-bearing support can be compromised even further as a result of the presence of a congenital anomaly (I) or by an oncological surgical intervention (J).
- Figure 1-5 A and B, The contrast between alveolar bone sustained by a healthy periodontal ligament and the resorption-vulnerable residual ridges that have been “periodontally deprived” for several years. C, Periodontal disease also leads to a similar result, a process that is even more dramatic once such teeth are extracted. D, In contrast, implant placement in the mandible aims at preserving what is left of the residual ridge and presumably reducing the risk of even further bone loss in the posterior ridges, a result of a prosthesis design that is more favorable for adverse occlusal stress distribution. The masticatory system's potential for self-inflicted enamel wear and tear (the body's hardest substance) is underscored in parts E to H.
- TABLE 1-2 DEVELOPMENT AND ADAPTATION OF THE OCCLUSION
- Function: Mastication and Other Mandibular Movements
- Parafunctional Considerations
- TABLE 1-3 DIRECTION, DURATION, AND MAGNITUDE OF THE FORCES GENERATED DURING FUNCTION AND PARAFUNCTION
- Historical Context and Current Considerations
- Changes in Morphological Face Height and the Temporomandibular Joints
- Figure 1-6 In A and B, the notion of a centric relation position may be best understood by studying mandibular border movements in both the sagittal and horizontal planes. A, The mandibular position in centric occlusion (CO) is depicted in 1, and centric relation or the most retruded position (B) in 2. Rotation, the terminal hinge movement (3) takes place between B and C, from which the translation phase of the posterior opening occurs to D, the maximum opening position (4). The most protrusive closure from D ends in E, maximum protrusion with tooth contacts, 5. The postural rest position (PR) and the habitual closure (H) are located well inside the borders. B, Envelope of motion (mandibular border movements) in the sagittal plane builds upon the previous illustration. C, The envelope of motion (mandibular border movements) as seen in the frontal plane. CO, Centric occlusion; CR, centric relation; MHO, maximum hinge-opening position; MO, point of maximum opening of the jaws; P, most protruded position of the mandible with the teeth in contact; Rest, postural rest position.
- Figure 1-7 Overt facial changes, especially circumoral, also may be seen in elderly patients with an intact dentition (A) as well as edentulous ones (B).
- Temporomandibular Joint Changes
- Esthetic Changes
- Figure 1-8 A and B, For over 30 years, maladaptive edentulous patients have been very successfully treated with osseointegrated, implant-retained fixed prostheses, especially in the mandible. C to F, The clinical technique also proved to be equally efficacious, indeed meritorious, for maxillary prescriptions. In this patient, advanced anterior bone resorption that resulted from prolonged occlusal overload at this site precluded traditional location for edentulous maxillary implant locations. The patient in parts G to I had enjoyed a prolonged adaptive complete denture experience but requested a “cure” for his edentulism. This was achieved via provision of osseointegrated teeth root analogues to support and retain fixed prostheses.
- Box 1-1 Morphological Changes Associated with the Edentulous State
- Behavioral and Adaptive Responses
- Treatment Options: Complete Dentures
- Treatment Options: Implant Prosthodontics
- TABLE 1-4 TREATMENT OPTIONS FOR EDENTULOUS PATIENTS*
- Figure 1-9 The osseointegration (OI) technique also can be used in an “abbreviated form” via the overdenture application. The technique lends itself to even more versatile applications. A to D, An example of an adult patient with surgically repaired edentulous cleft lip and palate. Both potential implant host bone site availability and circumoral morphology demanded the design of polished and occlusal surface that ensured the best facial support possible. The more routine use remains for edentulous mandibles using two or more abutments as well as diverse retentive components. E and F, Two implants splinted with a bar are used for clip retention. G to J, Adult patient in which snap attachments are employed for the three implant abutments.
- Figure 1-10 The challenge and dilemma of managing the edentulous predicament by means of complete dentures (with their time-dependent and unpredictable reliance on labile biological support) has been dramatically improved by the introduction of the osseointegration technique. The notion of a progressive, inevitable if variable RRR is no longer the dominant treatment concern since alternative and biologically tenable interventions are now available. The predicament of dealing with the substitution of PL support (A) by significantly less biomechanically suitable residual ridges (B) has been dramatically rectified by the predictability of successful outcomes associated with the induction of osseointegration (C). RRR, Residual ridge resorption; PL, periodontal ligament.
- Bibliography
- Chapter 1 The Edentulous State
- Chapter 2 Systemic Health Aspects and Nutritional Considerations for Edentulous Patients
- Mucosal Conditions
- Vesiculoerosive
- Systemic Lupus Erythematosus (SLE)
- Burning Mouth Syndrome
- Figure 2-1 Geographic tongue. Irregularly bordered areas of dekeratinized and desquamated filiform papillae appear as erythematous patches on the dorsum of the tongue bordered by elevated grayish white areas of acantholysis and hyperkeratosis.
- Box 2-1 Oral-Systemic Considerations That May Influence an Adaptive Prosthodontic Experience
- Box 2-2 Documented Possible Causes of Burning Mouth Syndrome
- Local Factors
- Systemic Factors
- Psychogenic Factors
- Mucosal Conditions
- Figure 2-2 Devastating effects of hyposalivation in four patients with Sjögren's syndrome. Note the extensive decay (A) and the typical pattern that develops at the gingival margins (A and B). Heavily restored dentitions (C and D) illustrate previous “Band-Aid” approaches to addressing the decay. Also note the dried, cracked tongue in both patients.
- Sjögren's Syndrome
- Hypersalivation/Hyposalivation
- Dietary Counseling of Patients Undergoing Prosthodontic Treatment
- Box 2-3 Nutrition Guidelines for Patients Undergoing Removable Prosthodontic Treatment
- Box 2-4 Risk Factors for Malnutrition in Patients with Dentures
- Figure 2-3 USDA's food guidance icon: MyPlate.
- The Aging Population
- Distribution and Impact of Edentulism in Old Age
- Distribution
- Impact
- TABLE 3-1 PERCENTAGE DISTRIBUTION AND PROJECTED INCREASES IN OLDER POPULATIONS BETWEEN THE YEARS 2000 AND 2020
- Mucosa
- Bone
- Saliva
- Figure 3-1 Angular cheilitis (A and B) and stomatitis (C) in an elderly man caused by malnutrition and/or liver dysfunction (white blood cell count, 3.19; hemoglobin, 12.4; hematocrit, 36.3; vitamin B12, 203).
- Skin
- Figure 3-2 An older face demonstrating the typical droop of the upper lip that accentuates the mandibular incisors.
- Teeth
- Figure 3-3 The influence of the vertical dimension of occlusion on the appearance of the face without teeth or dentures (A), with “old” dentures (B), and with “new” dentures (C).
- Control of Sequelae with the Use of Complete Dentures
- Dentures in Their Oral Environment
- Direct Sequelae: Changes in Local Mucosal Morphology
- Box 4-1 Direct Sequelae Caused by Wearing Removable Prostheses: Complete or Partial Dentures
- Figure 4-1 A and B, Mild to more severe palatal mucosal irritation and infection suggest stages in the development of a denture sore mouth (DSM). C, An implant gingivitis (often erroneously referred to as a so-called peri-implantitis) is present, and this is readily addressed with improved hygiene and soft tissue massage (D).
- Box 4-2 Interaction of Prosthetic Materials and the Oral Environment
- Surface Properties: Plaque Accumulation
- Chemical Properties
- Physical Properties
- Changes of Environmental Conditions
- Figure 4-2 A recently worn mandibular denture has caused a traumatic ulceration associated with a peripheral overextension.
- Traumatic Ulcers and Cheek Biting
- Denture Irritation Hyperplasia
- Figure 4-3 Very severe denture irritation hyperplasia in the mandible showing a central groove on the patient's right side in which the denture flange rests (indicated by the arrow).
- Denture Stomatitis
- Figure 4-4 Pinpoint hyperemia is a characteristic feature of type I denture stomatitis (A), while erythema of the entire mucosa in contact with the denture surface is characteristic of the type II variety (B). In type III, additional papillary hyperplasia, which may be nodular or mossy, is present (C).
- Box 4-3 Factors Predisposing to Candida-Associated Denture Stomatitis
- Systemic Factors
- Local Factors
- Candida-Associated Denture Stomatitis (Fig. 4-5)
- Etiology and Predisposing Factors
- Figure 4-5 A, Severe tissue trauma from an ill-fitting denture has led to both hyperplastic tissue changes and a Candida infection. The latter also can be manifested at the corners of the mouth as an angular cheilitis (B and C) that can be quite painful. Antifungal therapy combined with correct prosthodontic management helps alleviate the problem (D). Microbial plaque on the denture's intaglio surface is visualized with the stain erythrosine (E), while amicrobial deposits are seen penetrating irregularities in a denture's intaglio surface (F). G, A diffuse atrophic glossitis.
- Management and Preventive Measures
- Flabby Ridge and Pendulous Maxillary Tuberosities (See Also Chapter 5)
- Hyperkeratosis and Oral Cancer
- Residual Ridge Reduction
- Box 4-4 Some Proposed Etiological Factors of Reduction of Residual Ridges
- Anatomical Factors
- Prosthodontic Factors
- Metabolic and Systemic Factors
- Figure 4-6 Moderate to advanced residual ridge reduction in the mandible frequently leads to palpable and superficial location of the mental foramina. Consequently, painful denture pressure at these sites is frequently encountered.
- Figure 4-7 Candida growth on a permanent silicone liner in a mandibular complete denture leads to a rough, unclean surface that can provoke additional soft tissue irritation. In both A and B, this generalized material deterioration (left) is contrasted to a clean and uncolonized liner (right).
- Box 4-4 Some Proposed Etiological Factors of Reduction of Residual Ridges
- Atrophy of Masticatory Muscles
- Nutritional Status and Masticatory Function
- Box 4-5 Associations Among Xerostomia, Denture Wearing, Impaired Masticatory Function, and Undernutrition in Frail and Dependent Older Persons
- Reduced Stimulated Salivary Flow Rate Associated with:
- Box 4-5 Associations Among Xerostomia, Denture Wearing, Impaired Masticatory Function, and Undernutrition in Frail and Dependent Older Persons
- Chapter 5 History Taking, Treatment Planning, and Improving Denture-Bearing Areas for Edentulous Patients
- On History Taking and Treatment Planning for Edentulous Patients
- The First Visit
- Patient Attitude
- General Health and Dental History
- Treatment Planning
- Social and Behavioral Information
- Box 5-1 Synthesis of Key Information Domains That Facilitate Choice of Treatment Options
- History: The Patient's Story
- Dentist's Specific Observations
- Box 5-1 Synthesis of Key Information Domains That Facilitate Choice of Treatment Options
- Social and Behavioral Information
- Psychological Considerations
- Systemic Health Status
- The First Visit
- Extraoral Examination
- Temporomandibular Joint
- Figure 5-1 A to D, The influence of the presence of teeth (or their absence) on lip fullness and support is self-evident. This is especially so when assessed in the context of age-related skin changes and vertical dimension of occlusal support. E, Completion of complete denture treatment. F, Without (left) and with (right) complete dentures in place. G to I, The inevitable effects of skin aging do not detract from correct prosthetically created circumoral support.
- Cheeks and Lips (Fig. 5-1)
- Temporomandibular Joint
- On History Taking and Treatment Planning for Edentulous Patients
- Intraoral Examination
- Mucosa (Figs. 5-2 and 5-3)
- Figure 5-2 An extensive range of morphological tissue health variables must be diagnosed before treatment planning is finished and complete denture fabrication is started. Six different edentulous maxillae underscore some of the frequently encountered variables. A, This residual ridge shows minimal resorption and is covered by firm, healthy, soft tissues. Hamular notches are well defined, and no tissue adhesions are present. This maxillary basal seat area offers an excellent morphological prognosis. B, This residual ridge, though substantial, is irregular, with bony undercuts and small exostoses present. The left tuberosity is pendulous and mobile, and a large torus is present. A denture can be built on these foundations, but surgical considerations also should be addressed to optimize the basal seat area. C, Anterior localized ridge resorption has occurred and been replaced by hyperplastic tissue. This tissue usually is excised before impression making. When a patient's health precludes this option, a modified impression technique is employed. D, Home care and a regular recall program were not instituted for this patient. Consequently, the basal seat area became inflamed and an epulis resulted. Tissue rest, massage, and the prescription of a treatment liner should precede a surgical assessment in this patient. E, Advanced residual ridge resorption is evident, with low mobile peripheral tissue attachments and obliteration of the hamular notches. As a result, compromise in both peripheral and posterior palatal seals will not improve the diagnosis for a retentive and stable denture. F, A morphological picture similar to the one in E has been rectified by preprosthetic sulcus deepening with skin graft placement. This prescription used to be frequently employed in the mandible but has been virtually eclipsed by implant treatment.
- Figure 5-3 Six diverse edentulous mandibular morphological outcomes. A, A firm, broad, and well-developed ridge accompanied by a favorable tongue size and position suggests a good prognosis. B and C, Alveolar ridge undercuts are present, though ridge size differs substantially. Surgical removal of the undercuts can be readily avoided by prudent relief of the denture base. However, tender areas over the exostoses and/or the tori in C may have to be treated surgically to ensure a comfortable prosthetic experience. D to F, Hyperplastic replacement of the entire residual ridge does not usually provide a firm denture-bearing area. However, surgical excision may result in a significantly reduced basal area, as in E. Extension of the denture's posterior lingual flanges usually will allow for a stable denture in E. This objective may not be fulfilled in F because of the unfavorably high attachment of the floor of the mouth. Also notice the virtual continuity of mobile mucosa in the floor of the mouth and the labial/buccal vestibule. They are separated by a thin, mobile, fibrous band. From a morphological point of view, this does not provide a favorable prognosis. Preprosthetic surgery for placement of osseointegrated implants is likely to be needed in these situations.
- Infection (Fig. 5-5)
- Tongue (Fig. 5-6)
- Figure 5-4 Traumatic lesions associated with denture peripheral overextensions and patient failure to seek immediate clinical adjustment. A, A chronic response to an incorrectly designed posterior palatal seal. B, Severe irritation of a lingual frenum. C, Ulceration in a left hamular notch area.
- Figure 5-5 Clinical examples of palatal trauma resulting from prolonged wear of ill-fitting maxillary dentures. A, Generalized stomatitis with a superimposed Candida infection. B, A more overt fungal infection plus anterior ridge hyperplastic replacement.
- Figure 5-6 A prolonged experience of not having an entire, or even a partial posterior mandibular dentition present, allows the intrinsic musculature of the tongue to spread out to fill in the extra available space. This may pose management and adaptation problems, both during prosthesis fabrication and the patient's subsequent adaptation to the space restriction imposed by the presence of the new prosthesis.
- Saliva (See Also Chapter 2)
- Bone Ridge Morphology
- Figure 5-7 Time-dependent residual ridge resorption will frequently compromise the available support area for the denture's intaglio surface (A) and render the now superficially located mental foramina (B) quite vulnerable to painful contact with the denture's periphery.
- Tori (See Figs. 5-2 and 5-3)
- Bony Undercuts (Fig. 5-8)
- Figure 5-8 Bony undercuts occur in different locations in either edentulous arch (A and B) and in processed dentures’ peripheries (C). They may be taken advantage of so as to enhance a denture's retention via selective reduction of the acrylic resin border (e.g., one of the tuberosity undercuts and slight modification of the anterior ones [C]). A resultant change in the path of insertion and withdrawal of the prosthesis will then be required.
- Arch Relations
- Figure 5-9 Enlarged tuberosities (A and B) also may be associated with the so-called Kelly's syndrome, wherein the anterior part of a maxillary complete denture rotates into an upwards position, while the posterior tuberosity part appears to grow downwards. This morphological predicament is usually associated with an untreated Kennedy class 1 type of mandibular dentition, and the associated enlarged tuberosities may need to be surgically reduced to accommodate the replacement mandibular posterior dentition.
- Enlarged Maxillary Tuberosities (Fig. 5-9)
- Mucosa (Figs. 5-2 and 5-3)
- Existing Dentures (Fig. 5-10)
- Figure 5-10 A to C, Materials used to fabricate a patient's current dentures are usually easy to identify. However, additional information about the patient's home care and hygiene considerations also may be gleaned from studying old prostheses.
- Figure 5-11 Most frenula need to be accommodated in dentures’ peripheral extensions. Both the anterior labial maxillary frenum and the mandibular lingual one can be prominent and particularly active. They have to be looked out for when making final impressions and at the time of finalizing the fit of the processed denture bases.
- Additional Considerations with the Partially Dentate Patient
- Box 5-2 A Primer on Treatment Options
- Adjunctive Care
- Prosthodontic Care
- Box 5-3 Clinical Conditions That Suggest Need for Teeth Extractions
- Figure 5-12 A to E, The six clinical examples shown underscore the challenge of selecting a best individual treatment option when confronted with partial or complete dentitions that reflect neglect and disease plus their consequences, as well as dental care attitudes on any patient's part.
- Box 5-2 A Primer on Treatment Options
- Radiographs, Photographs, Measurements
- Radiographic Images (Fig. 5-13)
- Figure 5-13 Radiographic images are necessary to ensure that abnormalities and pathoses are identified, and if needed, addressed before complete denture management is undertaken. Fig. 5-7 identifies the superficial position of the mental foramina, while A shows favorable ridge morphology and tooth roots in posterior maxillary regions. Compromised ridge morphology is quite clear in B together with superficially located mental foramina. Both the two-dimensional quantity of bone support, size, and location of maxillary sinuses, plus presence of an alloplastic-only graft in the mandible, are clearly shown in C. This is a typical example of the sort of “scout” view for selecting implant host sites before more sophisticated imaging is undertaken.
- Photographic Images
- Measurements
- Radiographic Images (Fig. 5-13)
- Diagnostic/Study Casts
- Financial Implications
- Development of the Treatment Plan
- Figure 5-14 Why treatment plan.
- Summary
- Preprosthetic Nonsurgical Methods
- Managing Traumatized Tissues
- Figure 5-15 Patient education.
- Figure 5-16 A, Typical behavior of tissue under a constant load for 10 minutes. Notice the 90% recovery within 8 minutes after removal of the pressure. Total recovery requires 4 hours. B, Comparison of responses to tissue loading and removal of the load in an elderly adult and a young adult. The compression curve is essentially the same. However, the removal of load shows definite differences in rate of recovery. The load was 11 g/mm2.
- Occlusal Correction of the Old Prostheses
- Box 5-4 Objectives of Preprosthetic Surgical Prescriptions
- Managing Traumatized Tissues
- Surgical Correction of Conditions that Preclude Optimal Prosthetic Function
- Hyperplastic Ridge, Epulis Fissuratum, and Papillomatosis (Fig. 5-17)
- Frenular Attachments and Pendulous Maxillary Tuberosities
- Bony Prominences, Undercuts, Spiny Ridges, and Tori
- Figure 5-17 A, Mild and restricted palatal hyperplasia that contrasts with a severe example seen in B, which is accompanied by an overt stomatitis. An epulis fissuratum and its cause are shown in C and D, with hyperplastic ridge replacement in E and F.
- Figure 5-18 Mandibular (A) and maxillary (B) frenula that may undermine prosthesis retention may need to be surgically corrected. C, Flabby, mobile tuberosity should be excised as shown in part D (a, incisions made in fibrous tuberosity; b, wedge of fibrous tissue removed; c, incisions made under the mucosa for removal of all unwanted fibrous connective tissue; d and e, thin mucosal flaps fitted, trimmed, and sutured). In part E, the compromised vertical space challenge may be approached surgically, or better still, by reducing the height of the mandibular molar to accommodate the opposing acrylic resin base but without a prosthetic tooth.
- Figure 5-19 Different sized and located maxillary and mandibular tori (A to E) may be managed by relief design in the acrylic resin denture bases (shown in part B), or else by surgical excision. The latter is indicated if the tori are particularly large, extend distally in the maxilla so as to compromise the efficacy of the posterior palatal seal, or else preclude the desired basal seat coverage for a mandibular prosthesis.
- Pressure on the Mental Foramen
- Figure 5-20 Different sized and located exostoses (A and B) may interfere with comfortable and convenient wearing of dentures and their insertion/withdrawal.
- Figure 5-21 Enlarged genial tubercles that encroach on the available potential denture-bearing area in the mandible are infrequently encountered but may still have to be surgically reduced if denture stability is compromised. The problem can now be readily avoided by relying on implant abutments for the desired retention and support.
- Ridge Parallelism
- Figure 5-22 Alveolar ridge undercuts are shown in parts A and B. These bony morphological variations may be regarded as a clinical nuisance. However, they also may be readily recruited into a denture's retention objectives via planned modification of the acrylic resin flanges (C).
- Figure 5-23 Advanced residual ridge resorption (A) almost invariably leads to palpable and often painful superficially placed mental foramina (B).
- Figure 5-24 Sharp anterior ridges are suggested by this panoramic image (A) and as a result of gentle clinical palpation (B).
- Vestibuloplasty
- Box 5-5 Classifications of Residual Ridge Morphology
- Figure 5-25 Advanced anterior mandibular residual ridge reduction (RRR) leads to the mentalis muscle's origin ending up close to the ridge crest. In part A, the residual vertical height would lend itself to a sulcus-deepening procedure to allow scope for an enlarged acrylic resin base at this site. Part B, on the other hand, would be a candidate for an onlay graft given the short height of the residual mandibular site.
- Figure 5-26 A to C, A sulcus-deepening procedure requires surgical detachment of labial and buccal muscle attachments followed by placement of a mucosal or skin graft. While this approach yields a larger available area for acrylic resin coverage (D), it also risks a so-called “witch's chin” appearance as a result of localized altered morphology and muscle function (E). This outcome is equally evident when a more extensive sulcus deepening is carried out (F to H). The procedure is less frequently prescribed for the edentulous maxilla (I, J, and K). All of these preprosthetic surgical procedures have now been virtually eclipsed by routine implant placement and advances in bone grafting combined with implant prescriptions.
- Ridge Augmentation
- Figure 5-27 Ridge augmentation by means of an alloplastic material (A and B) or a homologous graft (C) also has been eclipsed by combinations of autologous bone grafting and implant placement.
- On History Taking and Treatment Planning for Edentulous Patients
- Improving Denture-Bearing Foundations for Edentulous Patients
- Considerations for Implant Prosthodontic Treatment
- Maladaptive Denture Behavior
- Figure 6-1 Treating the edentulous state with complete dentures presumes that acrylic resin is a reasonable substitute for the absent periodontal ligament and its participation in the maintenance of its surrounding alveolar bone. The space between the prosthetic teeth and the underlying bony support in part A reflects the reduced and profoundly changed support for a prosthetic occlusion. Attempts to compensate for this inherently compromised support mechanism have included a diversity of implant designs as shown in the clinical examples in parts B, C, and D. Regrettably, the resultant induced mechanical anchorage is characterized by a poorly differentiated connective tissue interface whose longevity is quite unpredictable.
- The Scientific Era in Implant Prosthodontics
- Figure 6-2 A to D, Brånemark's now classical osseointegration technique in an edentulous mandible. This method led to compellingly documented and long-lasting interfacial osteogenesis for implant abutments, with favorable functional outcomes irrespective of location in different host bone sites, age, or gender considerations.
- Figure 6-3 A to C, An elderly patient's annual recall examination appearance of successful management of long-standing maladaptive mandibular edentulism with a fixed prosthesis. D, Bryant's data underscore the comparable cumulative survival rates in older and younger groups of patients. E, The impressive bone maintenance levels around implants over a prolonged observation period can be noted.
- Figure 6-4 A and B, Clinical and laboratory examples of two abutments that are used to retain and support a mandibular overdenture (C). A diversity of retentive design features are employed (see Chapter 17 and Fig. 6-10, B and C).
- Box 6-1 Patients’ Signs and Symptoms That Frequently Preclude an Adaptive Complete Denture Experience
- Patient Considerations
- Figure 6-5 The profound and significant differences that exist between the natural dentition's biologically determined eruptive process (A and B) as compared with the induced healing response that results in osseointegration (C) has changed the traditional approach to managing partial and complete edentulism.
- Box 6-2 Differences Between Teeth and Implants
- Teeth
- Implants
- Maladaptive Denture Behavior
- Treatment Outcome Considerations
- Summary
- Box 6-3 Determinants of Treatment Outcome in Implant Prosthodontics (Toronto Consensus Conference, 1998)
- The Following Considerations for Successful Outcomes with Implant-Supported Prostheses Were Proposed:
- The Success Criteria Comprise the Following Determinants:
- Box 6-3 Determinants of Treatment Outcome in Implant Prosthodontics (Toronto Consensus Conference, 1998)
- Figure 6-7 A to F, The notion underscoring the benefits of the development of the “classic” overdenture technique. Dentists had long recognized the merits of recruiting one or more teeth—often irrespective of overall integrity—to enhance the retention and support of mandibular removable prostheses, as well as to retard additional and ongoing RRR. Clinical experience culminated in recurrent efforts to aim at preferably retaining two mandibular canines that are morphologically altered after root canal therapy and extraction of adjacent teeth that demonstrated advanced periodontal disease (G to J). The resulting overdenture abutments ensure dentogingival support for complete dentures and an expected reduction in RRR, at least around and between the abutments. Overdenture treatment planning reconciles clinical decisions regarding number and location of potential abutments, their restorative and endodontic status, and their use for retention and support. The logical extension of the above examples culminated in the routine placement of two or more abutments when employing the implant overdenture technique (K), although preliminary short-term evidence suggests that even one mandibular implant can be of benefit (L and M). A management strategy for any abutment's health status is, of course, also a required consideration.
- Figure 6-8 A to F, Congenitally missing maxillary teeth and severe crowding of the residual dentition undermined both the appearance and the functional efficiency of this patient. A maxillary overdenture supported by abutments with gold copings resolved both clinically challenging concerns. G to I, The natural dentition was initially left virtually unaltered when the maxillary overdenture was made. It was managed by the patient with regular fluoride gel application and relatively conscientious home care. At a recall appointment, the teeth's rough edges would obviously require some modification and minor restorative touch-up.
- Advantages and Disadvantages of the Overdenture Technique
- Box 6-4 Cited Advantages for the Overdenture Technique
- Indications and Treatment Planning
- Group 1
- Figure 6-9 A and B, Caries presents a major challenge in the effort to prolong the useful healthy life of overdentured abutment teeth. The prepared root surfaces were left totally “bare” in part B, although no periodontal disease progress was noted. C to E, In contrast, this patient's home maintenance program, which included fluoride gel use, has yielded good treatment outcomes.
- Group 2
- Group 1
- Selection of Abutment Teeth
- TABLE 6-1 CONSIDERATIONS IN SELECTION OF MAXILLARY TEETH AS OVERDENTURE ABUTMENTS
- Methods and Techniques for Enhancing the Overdenture's Retentive Role
- Figure 6-10 A to C, Different coping designs, with or without additional commercial attachments, are readily available.
- Loss of Abutment Teeth
- Summary: Treatment Outcome Studies
- Advantages and Disadvantages of Immediate Denture Treatment
- Contraindications to Immediate Denture Treatment
- Treatment Planning the Choice of the Immediate Denture Clinical Technique or Protocol
- Explanation to the Patient
- Oral Examination
- TABLE 6-2 COMPARISONS OF CIDs AND IIDs
- Box 6-5 Explanation to the Patient Concerning Immediate Dentures
- Box 6-6 Example of Informed Consent for Immediate Dentures
- Examination of Any Existing Prosthesis If it is to be Included in an Iid
- Tooth/Teeth Modifications
- Prognosis
- Figure 6-11 Planning CIDs for the maxillary arch (A and B) and both arches (C and D) would require having the mandibular anterior teeth modified so as to correct the uneven plane of occlusion, as well as changing the VDO to avoid the resulting anterior mandibular slide shown in B and D.
- Figure 6-12 Preextraction records on any patient may be determined even when a compromised residual partial dentition is present. This patient was scheduled for a maxillary immediate denture, and it was possible to acquire very useful information such as an evaluation of occlusal relations, smile line, midline, and posterior limit for prosthetic teeth placement, planes of occlusion, extruded teeth, and more via a simple clinical evaluation. However, this also can be conveniently done via mounted diagnostic casts, which will then serve as a permanent record.
- Referrals/Adjunctive Care
- Oral Prophylaxis
- Other Treatment Needs
- Considerations for Implant Prosthodontic Treatment
- The Potentially Edentulous Patient to Be Treated with Overdentures
- Immediate Dentures for Potentially Edentulous Patients
- Chapter 7 Materials Used in the Management of Edentulous Patients
- Box 7-1 General Requirements for Biomaterials Used to Make Complete Dentures
- Impression Materials
- Box 7-2 Optimal Qualities for Prosthodontic Impression Materials
- Nonelastic Impression Materials
- Impression Plaster
- Figure 7-1 A combined compound and zinc oxide eugenol wash impression. A, Impression compound is used to make an impression of the denture-bearing areas. B, Sufficient material is removed to allow space for the ZOE paste to record all the anatomic details with greater accuracy. C, ZOE paste is applied to the relieved compound. The material flows easily to produce good surface details (D).
- Zinc Oxide Eugenol (ZOE) Impression Paste
- Box 7-3 Zinc Oxide Eugenol (ZOE) Impression Paste
- Applications
- Box 7-3 Zinc Oxide Eugenol (ZOE) Impression Paste
- Impression Plaster
- Dental Impression Compound (Types I and II)
- Box 7-4 Compound Types: Composition and Manipulation
- Type I (Lower Fusing Material)
- Type II (Higher Fusing Material)
- Composition and Manipulation
- Important Considerations for Proper Use of Impression Compound
- Figure 7-2 Compound preliminary impression using a stock metal tray.
- Box 7-4 Compound Types: Composition and Manipulation
- Hydrocolloids
- Agar (Reversible Hydrocolloid)
- Figure 7-3 A and B, Compound must be applied in sections around the borders of the custom tray. A wax spacer is kept in place during this procedure to maintain adequate space for the final impression material.
- Box 7-5 Composition of Agar
- Composition and Manipulation of Agar (Box 7-5)
- Box 7-6 Composition and Setting Reaction of Alginate
- Figure 7-4 Alginate impressions in stock trays. Nonperforated trays must be coated with an alginate adhesive. The bulk of the material is due to its high viscosity and displaced tissues. Pencil outline marks the anatomical location of the denture-bearing areas. The mandibular impression may be underextended lingually because of a lack of support by the tray and/or utility wax.
- Agar (Reversible Hydrocolloid)
- Alginate (Irreversible) Hydrocolloid Material (Box 7-6)
- Technical Considerations in the Manipulation of Alginates
- TABLE 7-1 COMMON ERRORS ENCOUNTERED WHEN MAKING ALGINATE IMPRESSIONS
- Technical Considerations in the Manipulation of Alginates
- Recommended Technique for Final Elastomeric Impressions
- Points of Importance When Handling Elastomers
- Box 7-7 Polysulfide Rubber
- The Base
- The Accelerator/Reactor
- Box 7-7 Polysulfide Rubber
- Figure 7-5 Polysulfide impressions show excellent detail reproduction. However, the impressions need to be poured immediately to avoid distortion as a result of the loss of by-products and the continuous curing shrinkage that occurs.
- Box 7-8 Condensation Silicones
- The Base Paste
- The Liquid Accelerator
- Box 7-9 Addition Silicones
- The Base
- The Accelerator
- Figure 7-6 A, Polyvinyl siloxane (PVS) impressions of fixed partial prostheses. B, Implant-supported prosthesis. C, Complete denture. Because of the hydrophobic nature of PVS, complete dryness of the tissues is required for impression taking. The variability in the application of these materials is achieved by using the appropriate viscosity or combination of viscosities for the task: lower viscosity is used for capturing details; higher viscosities are used to support the wash materials. PVS has exceptional accuracy in reproducing anatomic details and its excellent dimensional stability allows for pouring a long time after impression taking. These properties render it an excellent material for occlusal registration (D).
- Figure 7-7 A, Polyether final impressions made using custom trays for an edentulous patient. B, Polyether impressions, boxed before pouring the casts in dental stone. C, Polyether material was used to border mold the custom tray with a wax spacer in place. Note that the posterior palatal seal area was recorded functionally using green stick compound. D, The final impression is made with the same material after removing the spacer, and applying an adhesive. E, Polyether final impression for implant-supported overdenture. F, Polyether pick-up impression. The material is dimensionally stable, so that casts could be poured not immediately after impression taking. However, the relative stiffness of the material limits its use for the production of multiple casts, but it is an excellent material for applications that require rigid support for pick-up copings.
- Box 7-10 Polyether Elastomer
- The Base
- The Accelerator
- TABLE 7-2 COMPARISON OF THE PROPERTIES, ADVANTAGES, AND DISADVANTAGES OF ELASTOMERIC IMPRESSION MATERIALS
- Box 7-11 Requirements of an Ideal Denture Base Material
- Box 7-12 Chemical Composition of Denture Base Resins
- Technical Considerations and Properties of Denture Base Resins
- Heat-Activated PMMA
- The Polymerization Cycle
- Denture Base Porosity
- Rapid-Cure Type Resins
- Figure 7-8 Processing errors in the heat-cured methacrylate resin bases may lead to an increase in the vertical dimension of the dentures, which is demonstrated by a rise in the incisal pin off the incisal guide table.
- The Bond Between Heat-Cured Denture Bases and Resin Denture Teeth
- Biocompatibility of Methacrylate-Based Resins
- Figure 7-9 Adverse reactions to methyl methacrylate. A, Direct contact with the methacrylate resin during packing of the resin dough by the laboratory technician resulted in dermal irritation. B, Direct contact of the oral mucosa resulted in severe irritation and inflammation.
- Residual Monomer Content
- Radiopacity of Denture Bases
- Injection Molding Technique
- Chemically Activated Resins (Box 7-13)
- Pour or Fluid Resin Technique
- TABLE 7-3 PHYSICAL AND BIOLOGICAL CONSIDERATIONS FOR HEAT-ACTIVATED RESINS AND THEIR CLINICAL IMPLICATIONS
- Box 7-13 Properties of Chemically Activated Resins
- Box 7-14 Properties of Microwave-cured Denture Resins
- Box 7-15 Properties of Light-activated Resins
- Microwave-Activated Resins (Box 7-14)
- Light-Activated (VLC) Resins (Box 7-15)
- Box 7-16 Limitations of Reinforced Denture Base Resins
- Modified Resin Base Materials (Box 7-16)
- Heat-Activated PMMA
- Methacrylate-Based (PMMA) Resin Teeth
- TABLE 7-4 CLASSIFICATION OF DENTURE BASE MATERIALS
- Figure 7-10 Denture prosthetic teeth. A and B, Resin denture teeth provide good esthetics and wear resistance and bond chemically to the resin bases. C, Composite resin denture teeth result in reduced wear to opposing enamel and gold surfaces than porcelain teeth. They could be the material of choice for single dentures opposing natural dentitions. Porcelain denture teeth are mechanically attached to the resin bases by pins (D) or diatoric holes (E). This bonding mechanism is a major disadvantage that limits the use of the teeth in complete denture fabrication.
- Box 7-17 Requirements of Prosthetic Denture Teeth
- Technical Considerations
- Figure 7-11 To ensure an adequate bond between the resin denture teeth and the bases, the ridge lap areas of the teeth must be free of any impurities such as wax or tinfoil-substitute before packing the mold following wax elimination.
- Esthetics of Methacrylate Resin Teeth
- Additional Advantages and Disadvantages of Methacrylate Resin Teeth
- Composite Resin Denture Teeth
- Porcelain Teeth
- Additional Advantages and Disadvantages of Porcelain Teeth
- TABLE 7-5 A COMPARISON OF THE PROPERTIES OF METHACRYLATE RESIN AND PORCELAIN TEETH
- Additional Advantages and Disadvantages of Porcelain Teeth
- Figure 7-12 A tissue conditioner must be evenly distributed over the whole denture-bearing areas. The material then provides improved adaptation of the denture base to the oral tissues for optimum stress distribution. This is done as a temporary measure before a definitive conventional (A) or implant-supported prosthesis (B) is fabricated.
- Short-Term Soft Liners (Tissue Conditioners)
- Box 7-18 Indications and Composition of Short-Term Soft Liners/Tissue Conditioners
- Indications for Use
- Composition of Tissue Conditioning Liners
- Figure 7-13 A mandibular denture with a tissue-conditioning material. The material was placed 6 months earlier. The patient presented with severe denture stomatitis, inability to masticate properly, and a feeling that “the denture felt too big in the mouth.”
- Rheological and Viscoelastic Properties of Tissue Conditioners
- Box 7-18 Indications and Composition of Short-Term Soft Liners/Tissue Conditioners
- Self-Administered Home Relines*
- Long-Term Soft Liners
- Methacrylate Resin and Heat-Activated Resilient Liners
- Box 7-19 Requirements of an Ideal Long-Term Soft Liner
- Chemically Activated Methacrylate Resins
- Silicone-Based Soft Liners
- Heat-Activated Silicone Liners
- Chemically Activated Silicone Liners (Room Temperature Vulcanized [RTV] Silicones)
- Methacrylate Resin and Heat-Activated Resilient Liners
- Technical Considerations
- Figure 7-14 A, A maxillary cast framework for an edentulous patient. The retentive meshwork is designed to hold the resin all around the borders and provides a posterior palatal seal area for optimum denture retention. The tuberosity area can be entirely covered in metal, or a mesh plus resin as dictated by the interarch space. B, A maxillary cast framework showing retentive coils to hold the resin. The rugae area has been reproduced for a natural feel. C, A mandibular cast framework with cast posts for added retention of the prosthetic teeth. Many dentists prefer not to cover the residual ridges with metal to allow for relieving and relining. D, The wax pattern is verified by the dentist before the base is cast using conventional lost-wax casting techniques. E, To decrease the weight of the maxillary denture, the palatal portion of the framework has been designed with a retentive mesh rather than a rigid solid palate. This design does not provide the same strength to the denture as those in parts A and B. However, it does allow for reline and increased adaptation, if needed.
- Box 7-20 General Requirements of a Cast Dental Alloy for Denture Base
- Cobalt-Chromium Alloys
- Cobalt-Chromium Nickel Alloys
- Nickel-Chromium Alloys
- Properties of Base Metal Alloys Used in Removable Prostheses
- Physical Properties
- Mechanical Properties
- Chemical Properties
- Biocompatibility
- Commercially Pure Titanium and Its Alloys
- Titanium Alloys
- Box 7-21 Advantages, Disadvantages, and Clinical Implications of Base Metal Alloys as Compared with Resinous Complete Denture Bases
- Figure 7-15 A and B, Calculus deposits on the polished, tissue surface and teeth of the complete dentures. The patient reported wearing the dentures at night. The underlying mucosa showed signs of inflammation.
- Box 7-22 Requirements of an Ideal Denture Cleanser
- Cleansing and Disinfecting
- Mechanical Techniques
- Chemical Denture Cleansers
- Oxygenating Cleansers
- Hypochlorite Solutions
- Other Techniques and Materials
- Ultrasonic Units
- Dilute Acids
- Enzyme-Containing Denture Cleansers
- Silicone Polymers
- Microwave Radiation
- Adverse Reactions to Denture Cleansers
- Summary of Cleansers
- TABLE 7-6 CONSTITUENTS OF DISADVANTAGES OF THE VARIOUS TYPES OF DENTURE CLEANSERS
- Adjunctive Retention by Using Denture Adhesives
- Indications and Contraindications for Denture Adhesive
- TABLE 7-7 CONTRIBUTING FACTORS TO THE RETENTION OF DENTURES
- Box 7-23 Requirements of an Ideal Denture Adhesive
- Application of Denture Adhesives
- Adverse Reactions to Denture Adhesive
- Chapter 8 Maxillary and Mandibular Substitutes for the Denture-Bearing Area
- Anatomy Of Supporting Structures
- Box 8-1 Maxillary and Mandibular Stress-Bearing Areas
- Maxillary
- Mandibular
- Mucous Membrane
- Residual Ridge
- Figure 8-1 Three-dimensional reformation reveals a class I ridge relationship and moderate ridge resorption 3 years after dental extraction.
- Figure 8-2 Lateral cephalometric radiograph reveals severe resorption in the maxilla and mandible with loss of the alveolar ridge down to basal bone. The patient now has a class III ridge relationship and extensive loss of facial support.
- Box 8-1 Maxillary and Mandibular Stress-Bearing Areas
- Anatomy Of Supporting Structures
- Maxilla
- Figure 8-3 The residual ridge is extremely knife edged. In this patient the posterior nasal spine (A) extends posteriorly as far as the hamular notch (B). The ridge has almost resorbed to the zygomatic process (C). The hamulus (D) is medial and posterior to the notch.
- Box 8-2 Areas Requiring Relief in Impression
- Figure 8-4 A, Maxilla: 1, labial frenum (not visible); 2, labial vestibule; 3, buccal frenum; 4, buccal vestibule; 5, coronoid bulge; 6, residual alveolar ridge; 7, maxillary tuberosity; 8, hamular notch; 9, posterior palatal seal region; 10, foveae palatinae; 11, median palatine raphe; 12, incisive papilla; 13, rugae; 14, displaceable soft and hard palate. B, Maxillary denture shows the corresponding landmarks: 1, labial notch; 2, labial flange; 3, buccal notch; 4, buccal flange; 5, coronoid contour; 6, alveolar groove; 7, area of tuberosity; 8, pterygomaxillary seal in area of hamular notch; 9, area of posterior palatal seal; 10, foveae palatinae; 11, median palatine groove; 12, incisive fossa; 13, rugae; 14, “butterfly” outline of posterior palatal seal.
- Peripheral Border Tissues And Contours
- Figure 8-5 A mouth mirror or ball burnisher can be used to palpate the hamular notch and displaceable soft and hard palate. Slide the mirror posteriorly along the crest of the ridge and the tuberosity. The mirror will fall into the notch.
- Figure 8-6 The vibrating line is located on the soft palate, and it elevates slightly when the patient says “ah.” Anterior to this line there is no movement on phonation.
- Figure 8-7 A, The buccal shelf is a dense cortical bone. The external oblique ridge (A) is the bony line where the buccinator muscle attaches. There is height of the alveolar ridge medial and superior to the external oblique ridge. B, This partially dentate patient has more resorption of the posterior alveolar ridge crest; therefore the mylohyoid ridge (B) and external oblique ridge (A) are now at the crest of the ridge. This denture intaglio surface would be flat rather than having the characteristic convex ridge contour.
- Figure 8-8 The sublingual and submandibular glands are above the crest of the severely resorbed ridge when the patient elevates the tongue and mylohyoid muscles. The denture will have compromised lateral stability.
- Figure 8-9 A, Genial tubercles (A), external oblique ridge (B), mylohyoid ridge (C). These serial sagittal cuts through the right side of the patient's mandible from anterior to posterior reveal the anterior attachment of the mylohyoid muscle low upon the genial tubercles, but moving posteriorly the mylohyoid attachment is parallel with the external oblique ridge. B, The view from inferior of the mandible of the same patient. The prominence of the mylohyoid ridge (C) towards the midbody and posterior extension can be very undercut, and the horizontal pull of the mylohyoid elevates and somewhat flattens the denture border and pushes the denture border medially. A, Genial tubercles.
- Figure 8-10 The posterior buccal flange and posterior lingual flange are often the same length as the external oblique and mylohyoid ridge in this area, and are at the same level on the mandible. There can be some contact of the flange with the buccinator and the mylohyoid muscles, but both muscles shape the length of the flange.
- Peripheral Border Tissues And Contours
- Figure 8-11 A, Partial edentulism has resulted in resorption of the posterior alveolus. The mental foramen is near the crest of the residual ridge. B, The sagittal cuts of the cone beam computed tomography (CT) reveal the mental foramen near the ridge crest.
- Figure 8-12 A, The anatomy and related denture form is noted here. 2, labial vestibule; 3, buccal frenum; 4, buccal vestibule; 5, residual alveolar ridge; 6, buccal shelf; 7, retromolar pad; 8, pterygomandibular raphe; 9, retromylohyoid fossa; 10, alveololingual sulcus; 11, sublingual caruncles; 12, lingual frenum; 13, region of premylohyoid eminence. B, Mandibular denture revealing 1, labial notch; 2, labial flange; 3, buccal notch; 4, buccal flange; 5, alveolar groove; 6, buccal flange, which covers the buccal shelf; 7, retromolar pad; 8, pterygomandibular notch; 9, lingual flange with extension into retromylohyoid fossa, 10, lingual flange; 12, lingual notch; 13, area of premylohyoid eminence.
- Figure 8-13 A, Cheek is retracted and the attachment of the buccinator muscle can be seen where it attaches along the external oblique line (A). This patient also has a denture ulceration due to overextension of his existing prostheses. B, When the cheek is relaxed it can be seen that the horizontal fibers of the buccinator will lap over the external surface of the denture flange, aiding peripheral seal. The retromylohyoid fossa (B) is noted.
- Figure 8-14 No extension was attempted in the retromylohyoid fossa because of the excellent ridge height and slight undercuts on the lingual of the ridge. The undercuts will require additional relief where the compound is showing through on the lingual borders. Negotiating the denture into the fossa would not be possible because of conflicting undercuts.
- Figure 8-15 A, Use of a mirror in the posterior mylohyoid area and asking the patient to protrude the tongue will diagnose the ability to gain extension into the posterior mylohyoid area. The tongue should be protruded only to the lips. B, This patient has slight elevation of the mouth mirror.
- Figure 8-16 Alginate impressions can easily extend into the retromylohyoid fossa for preliminary and final impressions.
- Figure 8-17 The denture border outline reveals the very overextended preliminary denture impression.
- Figure 8-18 A, This patient complained of an overextension after delivery. It was evaluated with thick pressure paste. B, Because the patient had implants and the denture was maintained in position, this slight overextension caused discomfort. C, Considerable extension was achieved into the posterior mylohyoid area.
- Impression Procedures
- Figure 8-19 A compound preliminary impression of the maxilla. It can be modified to become a tray for border molding a final impression.
- Figure 8-20 This patient has pressure from the posterior palatal seal of his existing denture, petechiae on the palate, and redundant tissue on the left anterior alveolus. He had a relief chamber in his existing dentures over the anterior palate, which is quite healthy. Tissue conditioning is required.
- Figure 8-21 This patient had anterior dental extractions performed 8 weeks earlier. She will be informed that a reline is likely necessary after her dentures are completed.
- Figure 8-22 Relief over the secondary stress areas of the rugae and midpalatine suture can occur with the vent holes. Vent holes were used in addition to a wax spacer.
- TABLE 8-1 MAXILLARY AND MANDIBULAR BORDER MOLDING
- Figure 8-23 A, Compound is placed on the tray that is approximately 2 mm short of the border. B, After placement of compound, it can be positioned beyond the expected height of the vestibule, heated, tempered in hot water, and placed in the mouth. If the tray was made too underextended, the compound can carry beyond 3 mm if carefully handled. C, The labial and buccal frenum are quite prominent and multiple in this patient. She border molded the area herself with instruction. D, The dentist can border mold the buccal tissues by gently pulling the lips and cheeks. The tray handle ideally is vertical, so as not to impinge on muscle movement. E, A maxillary irreversible hydrocolloid material in a stock tray was used for the impression. This denture has been waxed up to “educated and observed” contours at the instruction of the dentist.
- Posterior Palatal Seal
- Figure 8-24 This patient had a class III soft palate form. The ridge is V shaped and he has very high buccal frenum attachments. The palatal seal was placed on the displaceable hard palate to gain retention.
- Figure 8-25 A, The posterior palatal seal in the area of the tuberosity is positioned into a slightly overextended position. B, The custom tray is seated and the compound is pushed into the hamular notch and then the dentist and patient border mold the area. C, The notch of the pterygomandibular raphe can be noted. The excess material hanging vertically is trimmed.
- Figure 8-26 The final impression from the border molding in Fig. 8-25 reveals excellent capture of the anatomy of the posterior palatal seal in the hamular notches. The impression was cut back to the border molded palatal seal that denotes the definitive extension of the denture. The area of the wax spacer shows no pressure, but the left maxillary ridge has excessive pressure. The decision was to relieve the denture upon delivery using pressure indicator paste.
- Figure 8-27 The posterior palatal seal is created with impression wax. The denture should extend to the end of the wax.
- Boxing Impressions And Making The Casts
- Figure 8-28 Boxing with strip rope wax and sheet boxing wax. This creates a wall to confine the stone and creates strength along the border of the cast.
- Figure 9-1 Complete dentures have three surfaces that are designed to harmonize with the oral biological and functional environment they are placed in. A, The impression or intaglio surfaces are fitted to the supporting basal seats. The wax occlusion rims (B and C [shown diagrammatically]) are contoured to simulate the position of the dentures’ polished surfaces so that they contact and support the cheeks, lips, and tongue. The shaded area in C denotes the neutral zone. In D, the opposing occlusal surfaces of the dentures are designed to fit together. However, the mandibular teeth's position should not encroach upon the tongue's position in the neutral zone as in E. This would lead to instability of the complete denture base as contrasted with optimal prosthetic teeth positioning in F. The overall concept is also emphasized in Fig. 12-1.
- Figure 9-2 Three surfaces: impression, occlusal, and polished surfaces, involve the functional stability of the complete dentures and are influenced by tongue, cheek, and lip activities. The lingual and buccal polished surfaces of a mandibular denture (identified with arrows) are concave shaped to conform to tongue and cheek muscle activities, which tends to stabilize the denture (A to C). D, The tongue seats the mandibular denture against the concave lingual polished surface while transporting the food bolus onto the occlusal table. The action of buccinator muscle prevents lateral displacement of the denture.
- Neutral Zone or Arch Form Design
- Figure 9-3 These wax occlusion rims are used as provisional substitutes for the teeth in complete dentures or implant-supported prostheses and are employed to record first the neutral zone or arch form. A, The clinical continuum leading to the mandibular denture's try-in stage is illustrated via an acrylic resin trial denture base, next with a wax occlusion rim (stabilized even further in this situation by means of overdenture implant abutment support), and finally the prosthetic teeth setup that conforms to the simulated neutral zone. B, The custom-contoured wax occlusion rims are ready to be “notched” (C and D) for recording preliminary maxillomandibular relations. They will then be transferred to an articulator for the laboratory exercise of setting up the selected prosthetic teeth and completing the third or occlusal surface. The teeth setup permits the next clinical appointment's confirmation of esthetic satisfaction and a confirmation of correct occlusal relations. E to G, The posterior mandibular prosthetic teeth are replaced with a partial wax occlusion rim at the try-in appointment because of an incorrect posterior occlusal relationship. This facilitates a new confirmatory record to be made at the predetermined VDO. A fresh articulator remount will be required before the new setup of the posterior teeth is completed for a second try-in.
- Mandibular Arch
- Figure 9-4 A and B, A Kennedy class I partially edentulous mandible and the removable partial denture designed for it underscore the position of the artificial posterior teeth arrangement that is compatible with the neutral zone concept. The same principle applies to a dentate (albeit a restored one) mandibular dentition (C) and the edentulous mandibular arch, with anterior teeth in place (D) as one of the landmark guides for completing the posterior teeth setup. In all these clinical situations, a virtually straight or very slightly curved line drawn from lingual of the retromolar pad to a point just lingual to the crest of the ridge in the premolar region, can act as a guide for positioning artificial posterior teeth (E). Note that the posterior height of the occlusal plane is approximately two thirds of the way up the retromolar pad. This corresponds to about 1 to 2 mm below the top of the anatomical landmark (E).
- Maxillary Arch
- Figure 9-5 In the natural dentition (A), the tips of the maxillary canines are likely to be (+)/(−) 1 mm anterior to the center of the incisive papilla. Because this useful landmark's position in the edentulous maxillary arch (B) is rarely affected by anterior maxillary teeth extractions, it can be circled on the edentulous cast to provide a rough guide to positioning the maxillary canines. This principle is illustrated in C. It also should be noted that a mild inflammatory papillomatosis is present in B.
- Figure 9-6 Age-related and degenerative skin changes can create virtual continuity between the nasolabial fold and the corner of the mouth. However, a range of such changes is encountered with edentulous patients and this varies from relatively subtle ones in A and B to overt ones in C.
- Figure 9-7 The modiolus.
- Figure 9-8 A, A mandibular occlusion rim is tried in the mouth without the opposing maxillary rim in place. It is correctly judged to be overcontoured and insufficiently high to fulfill the objectives articulated in the text. It is important to note the resultant generalized circumoral lack of support, particularly the uneven lower lip, hence hardly visible, which is magnified by the absence of the maxillary occlusion rim. Corrective trimming and contouring of both wax rims served as an analogue for the mouth's neutral zone and culminated in optimal positions of both occlusal plane height and overall esthetic satisfaction with the position of the prosthetic teeth as seen in B.
- Esthetics
- Figure 9-9 The combination of favorable skin tone and correct prosthetic teeth placement as seen in A and B can provide very satisfactory and highly appreciated results for patients irrespective of their age or gender. At the initial try-in appointment for the patient in B, it became clear that the anterior teeth had to be reset more anteriorly to obtain the desired overall esthetic outcome. C, Note the more labial placement of the prosthetic teeth on the left side as opposed to the incorrect original setup's positions on the right side. This protocol provided both dentist and patient with an opportunity to compare different setup arrangements very readily and led to the preferred results in B.
- Phonetics (See Chapter 15)
- Mechanics
- Figure 9-10 A, Sectional casts, posterior view, A. When the teeth are centric occlusion, the incisal edges of the mandibular central incisors are on average 4 mm from the incisive papilla. Sagittal view of the central incisors, B. B, The vertical overlap is variable and often ranges between 0.5 to about 2 mm. This overlap is selected on the basis of esthetic and functional occlusal contact determinants.
- Box 9-1 Summary of the Clinical Steps Required to Develop the Polished Surfaces and Prepare the Occlusion Rims for Transfer to an Articulator
- Facebow
- Figure 9-11 Facebows may fit directly into each ear's external auditory meatus (A), or else have their rods placed over an approximate location of the so-called “hinge axis” (B). The bite fork is placed on the labial aspect of the articulated wax occlusion rims and carried to the articulator (C) so as to facilitate mounting the edentulous working casts on a selected arcon-type articulator.
- Laboratory Steps
- Figure 9-12 Three articulators: the simple hinge type (A) and arcon types that permit more accurate simulation of occlusal teeth contact determined jaw movements (B and C). The latter two also possess incisal guide tables that lend themselves to versatile use and a diversity of anterior and lateral teeth contact arrangements and designs. D, An arcon-type articulator superimposed upon a dry skull to suggest the theoretical merits of using a facebow for mounting the maxillary cast in a related hinge axis position. This would presumably provide an anatomical similarity of the resulting relationship between the teeth and the condyles. It must, however, be emphasized that even if this were to be the case, it would not ensure that the articulator's movements could provide a better clinical result when making complete dentures.
- Interocclusal Records
- Figure 9-13 A and B, The start and end points of the resultant curved condylar movement over the fossa is suggested on these dry skull pictures. However, this movement occurs in a straight path in the vast majority of articulators in current general use, as per the point made in Fig. 9-12, D.
- Graphic Records
- Hinge-Axis Records
- Programming the Articulator
- Condylar Elements (Fig. 9-14, A)
- Incisal Elements (Fig. 9-14, B and C)
- Figure 9-14 The condylar elements are set arbitrarily, or else estimated by means of a protrusive record. They are frequently set between 0 and 20 degrees, although in A the higher setting corresponds to a planned overlap in incisal guidance, lateral excursions, and cuspal morphological considerations. B and C demonstrate the ability of a semiadjustable articulator's incisal guide table to accommodate different angles for the lateral plates as dictated by the selected incisal arrangement.
- Arbitrary Settings
- Figure 9-15 Cuspless prosthetic teeth (A) are very easily set up on a flat plane when a zero condylar inclination is used with the incisal guide table also set flat at zero (B).
- On Meeting Patient Expectations When Selecting Teeth
- Figure 10-1 Use the correct shade guide for denture teeth. Some are porcelain-only shades.
- Figure 10-2 Photos as happy student, mother, and grandmother assist in determining tooth size and position. See result in Fig. 11-20, C.
- On Guiding Patient Decisions
- Figure 10-3 Central looks to be 8.7 mm wide (A) and 10.1 mm long (B). C, Six anteriors are 49 mm. D, Four posteriors are 34 mm and medium (M) height.
- Figure 10-4 A pair of tooth shades to compare. Ask your patient to point to the one that he or she prefers.
- Figure 10-5 Pair comparison to identify the best mold of teeth. The two teeth on the left and the two teeth on the right are from different molds. The patient can see them in the mirror, and he is pointing to the one he prefers.
- Additional Clinical and Technical Considerations in Anterior Tooth Selection
- Patient Preferences
- Overdentures and Implant Dentures
- Opposing Natural Teeth
- Materials for Denture Teeth
- Posterior Tooth Molds and Cuspal Anatomy
- Ten Landmarks for Complete Denture Teeth Setup
- The “Standard Anterior” Arrangement
- TABLE 10-1 TEN LANDMARKS TO FIND AND USE FOR DETERMINING DENTURE TOOTH POSITIONS
- Figure 10-6 The incisive papilla is used to help locate the midline of the dental arch. A, A mark is made on the cast through the center of the papilla. B, The mark is transferred to the occlusion rim as a guide to placement of the maxillary incisors.
- Arranging the Mandibular Anterior Teeth (Fig. 10-9)
- Figure 10-7 Indications of correct anteroposterior positioning of artificial anterior teeth. A, By measurement from the middle of the incisive fossa on the trial denture base to the labial surfaces of the central incisors. B, By visualization of the imaginary roots of artificial anterior teeth. The imaginary roots will be further in front of the residual ridge when a great amount of resorption has occurred. C, By determining the relationship of a transverse line extending between the middle of the upper canines and the incisive fossa.
- Mandibular Central Incisor Positions
- Figure 10-8 A, Vertical overlap of 0.5 mm and 1 to 2 mm of horizontal overlap must exist between the maxillary anterior teeth and their mandibular antagonists to achieve a low incisal guidance, which is needed for the anterior teeth to function in harmony with most posterior tooth forms. B, The low incisal guide angle is both esthetic and functional.
- Mandibular Lateral Incisors
- Mandibular Canines
- Setting The Maxillary Anterior Teeth (Fig. 10-10)
- Maxillary Central Incisors
- Figure 10-9 A, Lower anteriors set to corner of mouth are the anterior reference for the posterior occlusal plane. B, Lower anteriors set. C, Lower overbite and overjet to wax rim. D, Relationship of artificial lower teeth to the lower lip. Left, correct height; middle, too high; right, too low.
- Figure 10-10 A, Maxillary anteriors set for best smile, lip support, and vertical dimension. B, Maxillary anteriors set for minimal overbite and clear overjet.
- Maxillary Lateral Incisors
- Figure 10-11 Normal labiolingual inclinations of anterior teeth relative to the perpendicular. A, Maxillary central incisor. B, Maxillary lateral incisor. C, Maxillary canine. D, Mandibular central incisor. E, Mandibular lateral incisor. F, Mandibular canine. G, Except for the 2 upper centrals, all 10 other front teeth have variations in rotation and angulation. H, Mesiodistal inclination of anterior teeth relative to the perpendicular.
- Maxillary Canines
- Maxillary Central Incisors
- “Anteriors Only” Try-In
- Arranging Posterior Teeth
- Number of Posterior Teeth Set
- Lingualized Articulation
- Figure 10-12 A, Mandibular teeth are set in the neutral zone from cuspid, over the bicuspid ridge, to the middle of the RMP. B, Mandibular teeth positioned too far toward the buccal of the ridge (R) and too far toward the lingual (L). C, Positions of the mandibular teeth corrected from those shown in B. D, Maxillary posterior teeth will be set to match the mandibular teeth already set to mandibular landmarks.
- Figure 10-13 Maxillary anteriors and posteriors set.
- Figure 10-14 Curved plate to set mandibular posteriors on a curve to the middle of the RMP.
- Figure 10-15 A, Upper setup with palatal cusps to contact lowers. B to D, Anterior arch forms: square (B), tapering (C), and ovoid (D). E to G, Varying shapes of the natural dental arch: square (E), tapering (F), and ovoid (G). H, Upper second molar deleted. Lingual occlusion with buccal cusps not touching.
- TABLE 10-2 TOOTH MOLDS AND OCCLUSAL CONCEPTS
- Arranging Maxillary Posterior Teeth to Lingualized Articulation (Fig. 10-15)
- Figure 10-16 A, Anatomical teeth set in cross-tooth and cross-arch articulation. B, Anatomical teeth on left excursion with multiple right “balancing” contacts.
- Setting the Mandibular Teeth First
- Evaluating Bilateral Balanced Articulation
- Figure 10-17 A, Flat teeth set to a flat plane. B and C, Generous soft tissue hides flat posteriors. Diastema adds effect to minimal overbite and overjet. D and E, Anterior Angle class II division 2 smile prominence masks flat posteriors.
- Figure 10-18 A, Anterior overlap, flat setup with upper premolar deleted and lower molar ramp. B, “Balancing side” ramp for anterior excursion stability.
- Figure 10-19 A, The four landmarks for the mandibular occlusal plane, distal of cuspids and the middle of the RMPs. B, Anterior slight but definite overbite and overjet. Nonanatomical teeth to be set on a compensating curve from the cuspids. C, A point 1 to 2 mm below the top of the retromolar pad and the tip of the positioned mandibular cuspid are guides used in the placement of the mandibular posterior teeth. The central grooves of the posterior teeth are positioned on a line between the cuspid tip and the middle of the RMP. When only three posterior teeth are arranged, it is essential that the central grooves of the molars be positioned slightly to the buccal to avoid crowding the tongue. D, The mediolateral curve is formed by slightly elevating the buccal cusps of the posterior teeth above the lingual cusps. The curve usually does not exceed 10 degrees from the horizontal plane. E, The left second molars provide the “balancing” contact on a right excursion with this anterior overbite and overjet. F, No spacing is needed with nonanatomical teeth set in a curved occlusal plane. G, Wax-up ready for trying-in appointment.
- Figure 10-20 The inclination of anterior teeth often parallels the profile line of the lower third of the face. Prognathic and retrognathic profiles require different tooth setups.
- Figure 10-21 A and B, Angle class 2 division I. Male prominent midface required protrusive upper teeth with a generous overbite and overjet. C and D, Angle class 2 division II. Female prominent midface with facial musculature required the upper teeth to be set in a retracted angle with deletion of the 4 bicuspids to recreate her previous natural dentition.
- Figure 10-22 A, Large wide prominent mandible with small narrow retruded maxilla. B, Posterior crossbite setup with upper teeth lingual to lowers for best stability of both. C, Complete anterior and posterior crossbite for prognathic patient. D, Correct inclination of the teeth and incisal edges in a moderate prognathic relation.
- The Lingual Look Test (Fig. 10-23)
- Figure 10-23 The Lingual Look test to confirm that maxillary palatal cusps are in full contact with the mandibular dentition.
- Completing The Wax-Up For The Try-In Appointment (Fig. 10-24)
- Figure 10-24 A, Excess melted pink baseplate wax is applied to all teeth to seal them in place. B, Cut back excess wax with a sharp spatula to create a clean tooth surface and a smooth gingival margin. C, Shape a clean natural papilla contour with no crevices for staining. D, Brush with a laboratory toothbrush to soften and blend wax spatula cuts. E, Palatal rugae add realism. F, Very light quick alcohol torch puffs create a smooth glazed surface. G, A cold, soapy gauze adds a final cleaning and luster.
- Before The Try-In Appointment
- TABLE 11-1 TWENTY-SEVEN POINT CHECKLIST FOR THE WAX TRY-IN APPOINTMENT
- At The Try-In Appointment
- Explanation
- Chairside Comparison
- Figure 11-1 A conformative approach. The right side waxed-up dentures are similar to the patient's existing prostheses on the left.
- Figure 11-2 A reorganized approach. The new denture on the right is purposely different from the previous denture on the left.
- Denture Comparison
- Figure 11-3 Record the existing VDO by measuring two skin points.
- Figure 11-4 An Alma gauge records the vertical and horizontal distance between an incisal edge and the incisive papilla intaglio.
- Figure 11-5 A, Wax-up measurement of papilla to incisal edge in millimeters. B, Wax-up measurement compared with existing denture. It is slightly greater as planned. C, Mandibular wax-up incisor to ridge measurement. D, Wax-up measurement compared with existing denture plus the soft liner. It is increased as planned.
- Figure 11-6 The moment of truth when your patient first sees her smile!
- Speaking And Phonetic Assessment
- Vertical Dimension Of Occlusion
- Figure 11-7 A, The smiling lips frame an image with the midline in the center. B, Perspective and dental proportion. The laterals, cuspids, and bicuspids blend posteriorly and follow the lower lip line. C, Subject and background. Upper front teeth are the subject. Gingiva, the interarch space, and lower teeth are background. D, Negative smile line not in harmony with soft tissues. E, Positive smile line follows lower lip contour. F, Complete upper and lower dentures have a pleasing appearance created by proportion between upper/lower and anterior/posterior teeth, subtle interarch space, gingiva in background, positive smile line, and facial support. G, Muscles that maintain facial support. When artificial teeth and the denture base material restore the lips to their correct contour, the facial muscles will be at their physiological length, and contraction will create the normal facial expression of the patient. H, Functional unit of the buccinator. This muscle (1) and the orbicularis oris muscle (2) depend on the position of the upper denture for their proper action. The pterygomandibular raphe (3) and the superior constrictor of the pharynx (4) also are shown.
- Figure 11-8 A, Identify facial landmarks and lines to which the smile will blend. The middle drawing shows that such parallelism provides a necessary harmony of lines. Notice the disharmony of the left and right. B, Using dental floss to confirm the dental midline to the facial contours.
- Figure 11-9 A, Existing dentures lack visibility because of bone resorption and tooth wear. B, Wax-up better visibility, but occlusal plane needs adjustment: down on left and up on right.
- Figure 11-10 A, Teeth did not show during speaking the “50s.” B, VDO increased by resetting upper and lower teeth for speech.
- Figure 11-11 Patient counting through the “60s” to assess anterior tooth positions.
- Check the Dental Occlusion
- Relaxing and Rehearsal of a Relaxed Jaw Closure
- Figure 11-12 A, Reorganized upper wax-up on left has changed arch and increased vertical height. B, Reorganized lower wax-up on right has appropriate increase in tissue coverage and vertical restoration. C, Left, New upper and lower prostheses in proportion. Right, Previous prostheses were inadequate. D, Old dentures can only create a collapsed class III profile with redundant lips. E, New wax-ups restore facial profile and pleasing appearance.
- Single-Base Stabilization for Try-In Assessment (Fig. 11-13)
- Figure 11-13 Stabilize the lower base. Use your two fingers and thumbs to clamp the lower wax-up on the mucosa while gently allowing the patient to close.
- Double-Base Stabilization for Try-In Assessment (Fig. 11-14)
- Figure 11-14 Stabilize both bases. The left finger and thumb hold the upper up and the lower down, while the right thumb and finger gently guide on the chin.
- Figure 11-15 “Stop when you feel the teeth first touch.” Look to see where and how the teeth are touching.
- Figure 11-16 Feel how the bases move when teeth close from “first touch” to “all the way.”
- When Is A Remount Needed?
- TABLE 11-2 REMOUNTS FOR COMPLETE PROSTHESES IN DENTISTRY
- Remount at Increased Vertical Dimension (Fig. 11-17)
- Remount at Correct Vertical Dimension (Fig. 11-18)
- Figure 11-17 A, Wax-up ready for try-in. B, Relaxed jaw closure and stable bases, but not all teeth are touching. C, Tripod of Aluwax contacts to record jaw position just open from any tooth contact. D, Each Aluwax record is slightly different in thickness. E, Use sticky wax and Q-tip to make sure the teeth do not move during remounting. F, After reset, the second wax try-in looks better.
- Figure 11-18 A, Wax-up try-in has anterior open bite and excess overjet with relaxed closure to a posterior-only contact. Wax registration must have been made to a protruded position. B, On relaxed closure along arc (C), the single posterior interference at B produces the anterior open bite. To achieve occlusion (A), patient must learn to shift jaw with muscles, or slide denture bases on mucosa. Neither is acceptable! C, Interfering posteriors are removed to allow corrected VDO. Anterior right central is set for best position and visibility. D, Remount at correct VDO. All anterior and posterior teeth will be reset. E, Situation recovered. The second try-in confirms pleasing smile of midline, occlusal plane, proportion, and stable occlusion. F, Balanced opposing lines. Dissimilarities in the inclination, rotation, and position of the teeth on each side of the midline provide what is called asymmetrical symmetry, which is essential for natural-appearing teeth.
- Figure 11-19 A, Wax tripod makes a new interocclusal record for remounting. B, The wax tripod must create a stable unmistakable position out of the mouth. If not, improve. C, Notch the plaster and tap to separate the master model from the mounting. D, Trim 1 cm from the upper plaster to create the space for a thin plaster remounting. E, Gouge and wet the trimmed plaster to hold a new plaster mix. F, Sticky wax the newly registered wax-ups and models together. Replace the trimmed plaster mount. Everything must be secure. G, Hold the models so that they do not move. Close the upper arm into soft plaster mixed with slurry water. H, Hold the pin down with an elastic band, and let the plaster mount harden before resetting the wax-up.
- The Interappointment Laboratory Procedure for the Wax Try-in Remount (Fig. 11-19)
- Resetting the Dentition for Try-in
- Try-In For Esthetics
- The Next Level: Characterization of Individual Tooth Colors and Position
- Figure 11-20 A, Minimum wear standard arrangement restores smile. B, A simple sketch by the dentist of the outline form of artificial teeth will be helpful in planning the incisal wear to be incorporated for a particular patient. Dotted line shows the original appearance of the incisal edges of artificial teeth; solid line shows the incisal wear anticipated. C, Incisal wear for a realistic appearance relative to age. See patient records in Fig. 10-2.
- The Next Level: Characterization of Individual Tooth Colors and Position
- Figure 11-21 Characterization with colors: use different tooth colors to create the best effect. A, The prominent position and color of this patient's maxillary right central were identified from a photograph. B, The maxillary central incisors were Dentsply shade 102; the rest of the smile was Dentsply shade 114. This emphasized the tapered arch form and created the illusion of more prominence for the upper right central incisor than was prosthetically possible. The smile appears real to this patient.
- Figure 11-22 Characterization by grinding: immediate dentures allows for realistic tooth selection and shaping. A, A previous photograph hints at the prominence of the maxillary central incisors, their overlap of the lateral incisors, and the Angle class II relationship. B, A study model allows selection of the best available mold. C, The acrylic teeth are trimmed to re-create the actual tooth shape. It could not be found in any mold guide. D, The completed prosthesis faithfully replicates the irregularity of tooth color, size, mold, and Angle class II position. This patient's smile looks real.
- Figure 11-23 A, Realism. Small spaces, a gold inlay, a clasp, and five silver amalgam restorations added for a smile. B, Realistic prosthetic smile created with a bicuspid gold inlay, irregular teeth arrangement, and chipped anterior teeth.
- Figure 11-24 A, Palatal seal identified on model. B, Wax-up extension confirmed in palatal seal area.
- Figure 11-25 PPS verification. A, Use a mirror to assess the depth of the hamular notch and palatal tolerance. Visualize a line from notch to notch through the fovea palatinae. B, The vibrating line and width of the posterior palatal seal depend on the soft palate form (A, B, or C). Form C allows only a narrow posterior palatal seal; A allows the widest seal.
- Figure 11-26 Sagittal diagrammatic view of denture in place in the mouth. A bead on the posterior extent (A) is 1 to 1.5 mm high and 1.5 mm broad at the base, and 2 mm anterior to the end of the denture (B). C, Movable soft palate. D, Muscles of the soft palate.
- Figure 11-27 A, The denture ends on the cast at A. The bead (B), located 2 mm in front of the vibrating line, is extended laterally through the center of the hamular notches. B, PPS position and depth carved into final model and contour in the processed base. C, At insertion, the PPS shows through the pressure-indicating paste (PIP).
- Figure 11-28 Confirm a preferred shade of gingival acrylic.
- Figure 11-29 Patient's statement of satisfaction with the arrangement of artificial teeth.
- The Laboratory Prescription
- Figure 11-30 “The Neutral Zone.” Make gingival contours so a patient can use muscles to stabilize their teeth.
- Waxing and Processing the Dentures
- Development of the Proper Forms of the Polished Surfaces
- Figure 12-1 Three surfaces—impression, occlusal, and polished surfaces—involve the functional stability of the complete dentures.
- Figure 12-2 The lingual and buccal polished surfaces of a mandibular denture are concave to conform to the tongue and cheek so the muscles will grip and tend to seat the denture.
- Figure 12-3 The tongue seats the mandibular denture against the concave lingual polished surface while transporting the food bolus onto the occlusal table. The action of buccinator muscle prevents lateral displacement of the denture.
- Completion of Wax-Up and Festooning
- Formation and Preparation of the Mold
- Figure 12-4 A and B, All excessive wax should be removed from the land areas of the master cast (arrows). C, A small end waxing knife is held 45 degrees to form the wax gingival margin. D, Note that the length of the cuspid and the premolar is similar to the natural state, and the gingival outline gradually tapers toward the occlusal plane to mimic natural teeth display. E, Esthetic festooning of the anterior teeth to display the CEJ and natural-looking gingival outline form and contour. The maxillary and mandibular canine eminences are reproduced to properly support the lips and the corners of the mouth.
- Figure 12-5 A, Proper form of the lingual polished surface contour. B, Position of the tongue relative to the lingual surface of the denture base is accommodated in the concave lingual polished surface.
- Figure 12-6 A, The normal lingual contour of the posterior denture teeth is established during the waxing procedure. B, The palate contour of the upper central incisor is reestablished to aid phonetics.
- Figure 12-7 A, After completion of festooning, seal periphery of the denture flange to inner edge of the land of the cast. The wax should be flush with the land. B and C, After soaking the master casts and mountings in water for a few minutes, gently remove the casts from the mountings. Note no damage on the master cast and the mounting. This allows cast reattachment to the mounting after processing.
- Figure 12-8 Master casts and wax dentures fit easily in the bottom half of the flasks.
- Figure 12-9 First half of flasking of the maxillary denture. A, Cast too high in area 1 and 2. B, Area 1 and 2 at a favorable level. C, Area 1 and 2 should be beveled. D, Area 3 and 4 to be beveled.
- Figure 12-10 A and B, The denture flasks are partially filled with plaster and the casts are then positioned within the flask so that the land of the cast (red arrows) is on the same level as the edge of the flask (yellow arrows). C, The upper portion of the flask is placed into position. Note that the denture teeth fall below the top level of the flask. D, A thin layer of improved dental stone is applied to the surface of the trial denture. Note that the occlusal and incisal surfaces of the denture teeth are partially exposed (arrows). E, The flask is then filled with plaster and the top of the flask is placed into position. The excess plaster is expelled through holes on the top (arrows). F and G, The flasks are heated in very hot water and then separated. H, The wax is then washed away with streams of hot water. I and J, The wax and the record bases have been completely removed. The denture teeth are imbedded in one side of the flask and the master casts are imbedded in the other side. K and L, After drying the stone, both sides of the flask are covered with a tinfoil substitute. Care must be taken to avoid coating the denture teeth with the tinfoil substitute.
- Packing the Mold
- Fabrication of Facebow Transfer Jig
- Laboratory Remount and Equilibration (As # 2 Remount in Table 11-2)
- Figure 12-11 A, An acrylic resin dough is made by adding polymer to monomer in the proper amounts. B, The flask is closed in a press with a sheet of plastic (arrow) placed in between the two halves. C, After several closures and when the resin has been suitably compressed, the plastic sheet is removed, and the flask is closed and placed in a press and then placed in a curing tank.
- Removing Processed Dentures from the Master Casts
- Figure 12-12 Fabrication of facebow transfer jig: Attach processed upper denture with its mounting and a record of its relationship to the articulator is made in fast-setting plaster on the lower mounting ring. Only the incisal and occlusal surfaces of the denture teeth engage the plaster.
- Figure 12-13 Laboratory remount: processed dentures on the casts are reattached to the plaster mountings of the articulator. The changes that occurred in the processing of the acrylic resin have caused errors in the occlusion.
- Finishing and Polishing Dentures
- Fabrication of Clinical Remount Casts
- Hydrate the Dentures
- Figure 12-14 A and B, Fabrication of remount casts. Begin by blocking out the undercuts associated with the tissue-bearing surface of the dentures with moistened pumice. C and D, Mix a small amount of plaster, place it on the lab bench, and imbed the denture into it as shown. E, Lower denture removed from the remount cast. All the blockout material should be removed, and the denture should fit accurately on the cast. F, The maxillary remount cast is attached to the maxillary member of the articulator using the facebow transfer jig.
- Development of the Proper Forms of the Polished Surfaces
- Elimination of Basal Surface Errors
- Adjustment of Denture Base
- Figure 12-15 Dry the denture first and then run the brush with the same direction and apply a thin even layer of pressure-indicating paste (PIP) onto the surface of the denture.
- Figure 12-16 The PIP pattern indicates severe pressure on the portion of the denture that overlies the torus.
- Adjustment of Denture Borders
- Errors in Occlusion
- Clinical Remount and Occlusal Equilibration (As #3 Remount in Table 11-2)
- Centric Relation Record
- Remount the Mandibular Denture
- Verifying Centric Relation
- Protrusive Record (Optional)
- Figure 12-17 A and B, Place low-fusing modeling compound (ISO) that has been softened in a water bath at 110° F on the occlusal surfaces of the mandibular denture. Place the mandibular denture in the water bath for 10 seconds. C, Place the lower denture with softened ISO compound intraorally and have the patient close in CR just short of tooth contact. Instruct the patient to retrude and elevate the tongue. Some gentle manual guidance on the patient can be applied simultaneously in a hinge movement. This will ensure the condyles are properly seated while obtaining the CR record. D, Remove the CR record. Chill in cold water until it is hard, and trim the excess with a scalpel so that only the cusp tip indentations remain. Trim the buccal side so that the seating of the dentures can be visually checked. E, The dentures and trimmed CR compound record are positioned together before reinsertion to recheck the accuracy of the record intraorally.
- Figure 12-18 The mandibular denture on the remount cast is mounted on the articulator with locked centric control.
- Figure 12-19 Protrusive record: Instruct the patient to bring their mandible forward 3 to 5 mm at about edge-to-edge position and then gently close into registration compound material.
- Eliminating Occlusal Errors in Anatomical Teeth
- Figure 12-20 Correction of errors in CR occlusion. Grind the shaded areas. A, Teeth too long. B, Teeth too nearly end to end. C, Too much horizontal overlap.
- Figure 12-21 Correction of errors on the working side during lateral excursion. Shorten interfering contacts as indicated by the shaded areas. A, Upper buccal and lower lingual cusps too long. B, Upper buccal cusps too long. C, Lower lingual cusps too long.
- Figure 12-22 Correction of errors in the mesiodistal relationship during protrusion. Grind the shaded areas. D, Distal surface; M, mesial surface.
- Figure 12-23 Eliminating deflective occlusal contact on the balancing side. Grind the lingual incline of the mandibular buccal cusp. B, Buccal surface; L, lingual surface.
- Eliminating Occlusal Errors in Nonanatomical Teeth
- Advantages of Balanced Occlusion in Complete Dentures
- Special Instructions to the Patient
- Individuality of Patients
- Appearance with New Dentures
- Mastication with New Dentures
- Speaking with New Dentures
- Oral Hygiene with Dentures
- Preserving the Residual Ridges
- Educational Material for Patients
- Twenty-Four-Hour Oral Examination and Treatment
- Examination Procedures
- Adjustments Related to the Occlusion
- Adjustments Related to the Denture Bases
- Figure 12-24 A, Note the ulceration at the midline of the posterior palatal seal area. B, The PIP pattern reveals the bead is too deep and too sharp.
- Figure 12-25 A, The anterior maxillary frenum is the most common frenum to become irritated from overextended denture. B, The disclosing wax pattern reveals the overextension area.
- Figure 12-26 A, Note the lesions associated with the anterior mandibular denture border. B, They correspond to the pressure-indicating paste pattern (arrows). C, Note the irritation associated with the denture border overlying the canine eminence. D, The pressure spot (arrow) shown by the pressure-indicating paste will be relieved and adjusted.
- Figure 12-27 In patients with severe resorption of the alveolar ridge, a portion of the inferior alveolar nerve may be exposed (arrows). Pressure in these areas may cause significant pain.
- Figure 12-28 The distobuccal flange of the maxillary denture is too thick below the border (arrows). Using disclosing wax along the border periphery and the thickness of the flange reveals the overextended areas.
- Figure 12-29 Notice the left buccal border in the region of the buccal notch (arrows). The buccal frenum, moving posteriorly over this border during facial expression, can loosen the maxillary denture. This area can be discerned from patient's complaint and checking with disclosing wax.
- Periodic Recall for Oral Examination
- Immediate Dentures
- Preliminary Impressions
- Final Impression
- Posterior Palatal Seal
- Figure 13-1 A, Smile showing uncomfortable, loose, extruded, drifted teeth with midline shift. B, Maxillary mirror image. Note fovea palatinae. C, Mandibular view mirror image. Excess calculus. D, Retracted view of occlusion. Upper teeth ready to fall out. E, Soft regular set alginate final impressions. All teeth are too loose for anything else.
- Maxillomandibular Relationship Records
- Figure 13-2 A, Wax relief and design for custom one tray immediate denture impression. B, Maxillary anterior teeth are nonsalvageable. Ready for immediate denture impression. C, Immediate denture custom tray perforated and posterior palatal seal enhanced. D, Alginate in custom tray impression for immediate denture.
- Figure 13-3 A, Diagram of the sectional or two-tray impression method. B and C, Posterior tray for mucosal impression picked up by anterior tray for teeth. D, Posterior mucosal border molded impression. E, Make sure the posterior impression is accurately replaced in mouth and then covered by anterior sectional tray for teeth. F, Anterior of two trays records anterior anatomy and indexes the posterior impression tray. G, Two trays removed together to make one immediate denture impression.
- Figure 13-4 A, Registration tripod of posterior wax cones in notches and anterior tooth contact. B, Ready for mounting. Pencil notations of midline, incisal reduction and extractions planned.
- Denture Teeth Arrangement
- Figure 13-5 A, The critical consult. Patient and spouse view one tooth setup and agree to midline shift. B, Labial drift and midline improved and agreed. C, Second viewing. Agree on full wax-up, clasps, enamelplasty. D, Second viewing. Confirm acceptance of palatal coverage and arch form.
- Laboratory Procedures
- Figure 13-6 A, Bone loss penciled on model to estimate stone trimming and space for tooth setup. B, Alternate stone teeth removed and ridge trimmed for tooth setup. C, Set alternate teeth. Adjacent teeth are reference for incisal, labial, contact position. D, Remaining stone teeth removed and replacements set. E and F, Setup and wax-up completed for patient viewing and agreement before processing.
- Figure 13-7 Clear surgery template constructed on duplicate “surgerized” stone model (another patient).
- Teeth Removal and Denture Insertion
- Postoperative Care
- Figure 13-8 A, The tooth exchange. Extractions and sutures. B, The immediate insertion of complete upper and partial lower dentures. C, Patient is able to leave with teeth and postoperative instructions.
- Figure 13-9 A, Five days later. Suture removal and adjustments. B, Despite planning, a large buccal pressure ulcer has developed. C, Pressure-indicating paste (PIP) and adjustment for pressure ulcer. D, Denture adhesive for retention as swelling diminishes. E, Weeks later, previous advanced periodontal disease has created much tissue change. F, Soft liner molded and excess trimmed. G, Months later, mucosa is healthy and stable and further resorption is minimal. H, Soft liner is still present. Porous and rough surface needs changed. I, Soft liner completely removed. Palatal vent drilled. “Chairside” hard reline placed at correct occlusion and VDO. J, “Hard” reline cured out of mouth for 20 minutes in hot water bath. K, Reline trimmed and polished after curing. This protocol is good for a few months while the patient decides on a final treatment choice. L, One year of smile and function from “immediate” complete upper and lower partial dentures.
- Figure 13-10 Alveolar bone preserved with overdenture retained roots.
- Treatment Planning for Overdentures
- Figure 13-11 A, Modern overdenture therapy. The logical extension of the concept to implants instead of deteriorated roots. B, Retentive elements in the denture base are adjustable and replaceable. C, Implant overdenture security, retention, and comfort make patients happy.
- Figure 13-12 A, Tooth-supported overdenture especially valuable to avoid a single denture opposing natural dentition. B, Mandibular overdenture stabilized with two roots.
- Retention
- Figure 13-13 A, If roots have length for an adequate post, attachments can make overdentures more retentive. B, Retentive elements need space. Avoid thin areas in the overdenture.
- Insertion
- Tooth-Supported Complete Denture
- Tooth-Supported Immediate Complete Denture
- Figure 13-14 A, Compromised teeth need a casting to protect. Electrosurg and sulcus expansion cord in place. B, Overdenture casting. Chamfer subgingival margins and post retention. C, Overdentures reinforced with cast Cr-Co mesh. D, Five-year follow-up. Three roots protected with composites, bonding resin, and fluoride. One casting to restore domed contour just above gingival. E, Root-stabilized overdentures give this smiling tuba player the security he needs to manage his embouchure and mouthpiece.
- Figure 13-15 A, Immediate overdenture solution. Failing fixed prosthesis and patient wants to keep teeth, not get implants. B, “Immediate” overdenture ready for insertion. C, Nonvital teeth remaining. Too few and too weak for fixed prosthesis. D, Prepared tooth roots for immediate overdenture insertion. Smooth, fluoride, and cover with bonding resin. E, Overdenture insertion. Direct reline to prepared tooth roots. F, Smile restored with tooth-supported single overdenture.
- Maintenance
- Figure 13-16 A, Success depends on recall maintenance. Fluoride, dentin bonding, and plaque control against gingivitis and caries. B, Overdenture is ideal tray for fluoride gel 3 times per week.
- Diagnosis and Treatment Planning
- Figure 13-17 A, A mandibular single denture may need a resilient liner for patient comfort. B, Processed silicone denture liner for single mandibular prosthesis. Try regular base first.
- Figure 13-18 A, Plan on cast Cr-Co mesh reinforcement if intact arch and heavy function. B, Cast mesh is embedded in PMMA at processing.
- Teeth Arrangement
- Figure 13-19 A, Parafunctional patient could still fracture reinforced single denture. Note wear on lower teeth. B, Frenectomy needed to restore labial flange integrity and strength. No more fractures occurred.
- Figure 13-20 A, Single prostheses have to match existing teeth. Use a facebow to best orient models on articulator. B, Opposing occlusion creates need for custom setting and adjustment of denture teeth. C, Posterior crossbite may best satisfy maxillary single denture stability.
- Figure 13-21 A, Existing teeth and esthetics sometimes create generous incisal guidance angle. B, Single prostheses cannot always develop balanced articulation with existing teeth. C, With careful shade selection and grinding, a smile can match opposing teeth. a, Vertical overlap; b, horizontal overlap; c, incisal guidance angle.
- Rebasing/Relining
- Treatment Rationale
- Figure 14-1 A number of changes can occur in the tissues that support complete dentures and are more common under mandibular than under maxillary dentures. They may be encountered under either, particularly when a maxillary denture is opposed by a natural or restored dentition. The magnitude of the changes is what determines the nature of the resurfacing or refitting prescribed. If a new thin layer of resin is added to the denture base, the resurfacing is called a reline. If more material is added (as for a maxillary denture resting on severely resorbed residual ridges), extensive refitting and replacement of the denture base are necessary, which is called a rebase.
- Diagnosis
- Figure 14-2 Bergman's and Carlsson's research comprised sequential cephalometric tracings from the mandibular symphysis region in 13 denture-wearing patients. The latter had been treated with immediate complete dentures and observed for 21 years after their extractions; all patients wore opposing complete maxillary dentures. All 13 composite tracings underscore the range and unpredictability of the morphological outcome. The data from this research serve as a strong reminder that clinical judgment regarding the mandibular denture's repositioning for relining purposes requires an understanding of resultant bone resorption outcomes. However, comparable information of similar changes in edentulous maxillae is not as compelling.
- Preliminary Treatment
- Figure 14-3 A to C, A composite traditional depiction of profiles and circumoral appearance that suggest aging, reduced, or collapsed VDO and the effects of ridge reduction on the appearance and occlusal relations of prolonged and unserviced denture wearing. D and E, Edentulous maxillae can be “hammered” into accelerated residual ridge reduction in the presence of severe occlusal overload. Maxillary complete dentures in these situations are likely to require frequent relining efforts.
- Figure 14-4 Loss of bone structure under both dentures, especially mandibular ones (A), permits the mandible to move upward a corresponding amount. As the mandible rotates to a closed position without translation of the condyles, it frequently moves forward, leading to a prognathic appearance. The clinical challenge is to determine the amount of change that has occurred in both basal seats and estimate the resultant dentures’ shifts. The occlusion is clearly incorrect when observed in the mouth of the patient seen in A, or it may appear deceptively adequate as in the patient seen in B, because the extraoral close-mouthed appearance can be almost identical in both situations. C and D, The edentulous maxilla had been previously opposed by a natural mandibular dentition for many years, with a resultant heavy biological price exacted from the integrity of the maxillary edentulous ridge. The resulting facial appearance and mandibular forward posturing demanded rectification via an implant-supported maxillary overdenture to achieve an esthetic result that was satisfactory for the patient. This situation had advanced beyond a straightforward maxillary denture reline solution. Note the unusual bar design associated with the anterior residual bone. A stud attachment (see Chapter 17) would include the need for such a retentive mechanism.
- Clinical Impression Procedures
- Static Impression Technique
- Box 14-1 Necessary Steps for a Closed-Mouth Reline Technique
- Functional Impression Technique
- Figure 14-5 The physical stages of tissue conditioners/treatment liners permit their versatile use for different clinical stages and objectives. Soft liners are primarily used to distribute functional stresses on residual alveolar ridges and reduce the amount of energy transmitted during both functional and parafunctional contact movements.
- Chairside Technique
- Relining/Rebasing Materials
- Static Impression Technique
- Repairs
- Denture Duplication (see Chapter 23)
- Bibliography
- Speech Production
- Figure 15-1 The different valves and articulators in the pharynx and the oral and nasal cavities that provide structural controls for speech sounds.
- Figure 15-2 A general schema of speech production and communication.
- Speech Production: The Role of Teeth and Other Oral Structures
- TABLE 15-1 ENGLISH CONSONANTS: THEIR VALVE POSITIONS AND MODES OF PRODUCTION
- Bilabial Sounds
- Labiodental Sounds
- Linguodental Sounds
- Linguoalveolar Sounds
- Figure 15-3 Effects of tooth positioning on f and v. A, Upper anterior teeth are too long. During the pronunciation of f, they will contact the lower lip in a position similar to v, and the sounds may sound alike. B, Effects of anteroposterior positioning of the teeth from left to right are correct, too far posterior, and anterior.
- Articulatory Characteristics
- Acoustic Characteristics
- Auditory Characteristics
- Figure 15-4 Vertical length of the anterior teeth during sibilant production from left to right is shown as correct, excessive, and with inadequate vertical overlap.
- Figure 15-5 Horizontal relation of the anterior teeth during sibilant production from left to right is shown as correct, excessive, and with deficient overlapping.
- Linguopalatal and Linguovelar Sounds
- Figure 15-6 Typical electropalatography diagrams for the sounds in “oh sadist.” Shaded area represents the contact between tongue and palate. Note the sagittal groove created when the s sound is uttered.
- Chapter 16 The Science of Osseointegration
- Osseointegrated Interface
- Factors That Determine Success and Failure of Osseointegration
- Implant Biocompatibility
- Implant Design
- Figure 16-1 A, A moderately rough surface characterized by an Sa of 1 to 2 µm and an Sdr% of 25 to 75 may serve as an example of most commercially available modern implants. This image presents a moderately rough blasted and anodized surface, with typical porosity achieved by anodisation. B, Bone tissue including ground substance and cellular components will need pores of a minimal size of 100 µm for ingrowth. Calcified ground substance of bone responds differently to irregularities in the micrometer size that are important for the strength of the osseointegrated response. Implant irregularities in the micrometer range are, to date, of undetermined significance for osseointegration.
- Figure 16-2 Marginal bone resorption is probably best explained by a compromised healing/adaptation theory, which suggests that the outcome of the healed interface will depend on a summation of the listed parameters. If this is of substantial magnitude, implant failure will occur, while a lesser magnitude may lead to bone resorption instead. This theory is strongly supported by clinical evidence that contrasts with other proposed theories for marginal bone resorption.
- Figure 16-3 Implants manufactured from titanium alloy, which represents a hard material, may demonstrate a very smooth surface outcome if a similar manufacturing approach, such as with softer CP titanium, is applied. Nano Tite PREVAIL implant with an Sa of 0.3 µm and an Sdr% of 17.
- Implant Surface
- Figure 16-4 Modern implants display clear nanopatterns in contrast to their respective predecessors. A, Astra Tech OsseoSpeed implant. B, Nobel BiocareTiUnite implant. C, A Biomet 3i Nanotite implant. D, An example of a predecessor implant Astra TiOblast without the typical nanopattern. All images 50,000× or more in magnification.
- Host Bed
- Figure 16-5 Implant topography is not all that matters. A, A blasted moderately rough surface whereas B is of a minimally rough (Sa 0.3 to 1.0 µm) implant reinforced with calcium ions. The two implants display a very similar bone response, presumably because implant chemistry (attached calcium ions) compensates for a smoother than ideal surface topography.
- Surgical Technique
- Loading Conditions
- Summary
- Bibliography
- Chapter 17 Implant Overdentures
- General Overdenture Treatment Considerations
- Inclusion and Exclusion Criteria
- Box 17-1 Inclusion Criteria for Implant Prosthodontic Treatment
- Presurgical Evaluation and Treatment Planning
- Figure 17-1 Correct imaging of potential host bone sites requires a mix of radiographs, which can be rendered more accurate by using a template with metallic markers of known dimensions (A). These markers will show up on a frontal (B) or sagittal image and allow for measurement adjustments in bone height or width. Required sagittal views of anterior edentulous zones are provided by means of cephalometric films, computed tomograms, or cone-beam radiography (C).
- Box 17-2 Exclusion Criteria for Implant Prosthodontic Treatment
- Box 17-3 Specific Objectives of Treatment Planning for a Patient with Implant-Supported Overdentures
- Figure 17-2 Mandibular overdentures have been shown to perform well when supported by only two implants. These prostheses are implant/ridge supported and can be so designed when implants are placed around 22 to 27 mm apart between the mental foramina. A to C, Freestanding or unsplinted design using ball abutments or magnets (D).
- Figure 17-3 Use of a connecting bar splints two implants and allows for rotation of the prosthesis around the interimplant axis. This can be achieved if the anterior residual ridge shape is only slightly curved and parallel to the arbitrarily determined hinge axis. The functional result simulates the effect of a class I Kennedy removable partial denture (RPD).
- Figure 17-4 A, Residual ridge curvature (as opposed to the “flat” one in Fig. 17-3) usually necessitates placement of three or more implants with an interimplant distance preferably exceeding 10 to 12 mm, to preclude the splinting bar's encroachment on tongue space. Should a bar's multiple segments follow the ridge contour, the prosthesis is then virtually entirely implant supported (B and C). The latter designs provide sufficient space for a number of retentive components that will not permit denture base rotation. The same effect probably results even if alternative retentive mechanisms are prescribed.
- Surgical Protocol and the Osseointegration Phase
- Figure 17-5 A and B, Application of a mandibular midline implant to support an overdenture.
- Figure 17-6 A, The maxilla's ridge contour is reflected in a segmented bar soldered to four implant abutments. B, Rigid splinting of multiple implants using a cast milled bar. Retentive clips or attachments can engage any or all of the available segments, ensuring good retention, optimal prosthetic teeth placement, and nonrestriction of tongue space.
- Prosthodontic Protocol
- Guidelines for Selecting Attachment Systems
- Box 17-4 Prosthodontic Approaches and Philosophies Used for Implant Overdentures
- Single Elements (unsplinted)
- Connected Elements (splinted)
- Indications for Ball or Magnetic Attachments
- Indications for Bar Attachments
- Box 17-4 Prosthodontic Approaches and Philosophies Used for Implant Overdentures
- Implant Overdenture Design
- Clinical and Laboratory Procedures
- Figure 17-7 A to D, Numerous attachment matrices have been commercially produced in an attempt to enhance or diversify claims for optimal implant/prosthesis retention. These methods are backed by strong anecdotal support.
- Figure 17-8 A and B, Horseshoe-shaped maxillary overdentures made out of a combination of prosthetic teeth, chrome-cobalt alloy (for strength with minimal bulk), and pink acrylic resin as a substitute for soft tissue reduction and for esthetic support. B and C, The undersurface of these prostheses includes retentive clips or attachments with milled edges that engage the bar segments.
- Figure 17-9 A to D, Popular manual or electric adjuncts for ensuring continued soft tissue health include brushing and stimulating periimplant tissues. The objective is plaque- and deposit-free implant components.
- Box 17-5 Step-by-Step Prosthodontic Procedures
- One
- Two
- Three
- Four
- Five
- Six
- Guidelines for Selecting Attachment Systems
- Patient Selection
- Box 18-1 Key Factors Associated with Long-Term Implant Success and Survival
- Considerations Specific to the Edentulous Mandible
- Figure 18-1 All-ceramic mandibular prosthesis (A) constructed in two segments (B) to permit a presumed independent movement of the left and right sides of the mandible.
- Immediate Load Rehabilitation of the Edentulous Mandible
- Step-by-Step Procedures
- Figure 18-2 Edentulous patient planned for mandibular osseointegrated fixed complete prosthesis. A, Occlusal view of mandible. B, Panoramic radiograph with radiographic markers for location of mental foramina. C, Modification of complete denture to act as surgical guide. D, Surgical placement of five endosseous implants. E, Attachment of abutments and provisional copings to implants. F, Relation of prosthesis to copings using autopolymerizing acrylic resin. G, Insertion of conversion prosthesis within 24 hours. H, Radiographic survey of provisional prosthesis in place.
- Figure 18-3 Atrophic maxilla secondary to a motor vehicle accident some 25 years before presentation. A, Failing maxillary fixed prosthesis. B, Photograph from before the accident reveals the smile line. C, Reflection of soft tissues revealing atrophic nature of residual alveolar ridge. D, Veneer grafting and sinus augmentation with iliac cortex and marrow. E, Dental implants placed into surgically preferred recipient sites. Rehabilitation of patient with a cement-retained ceramometal prosthesis. F, Multiple implant-retained parallel abutments in maxilla. G, Intaglio surface of maxillary ceramometal fixed prosthesis. H, Frontal view of prosthesis before insertion. I, Try-in of abutments and prosthesis illustrated on panoramic radiograph. J and K, Frontal views of prosthesis from intraoral and extraoral perspectives.
- Step-by-Step Procedures
- Figure 18-4 Edentulous patient planned for fixed implant-supported prostheses. A to C, Provisional prostheses demonstrating constrained interarch distance after esthetic and functional verification. D and E, Occlusal views of screw-retained ceramometal prostheses with strategic placement of maxillary implants for maximum force distribution. F, Frontal occlusal view of prostheses. G, Panoramic radiograph illustrating completed treatment.
- Form and Function
- Anatomic and Physiologic Considerations: Normal Function
- Figure 19-1 These lateral videofluoroscopic frames show the “at-rest” position of the soft palate (left) that postures against the base of the tongue and leaves the nasopharynx open for respiration. During swallowing (right), the soft palate sharply elevates as the pharyngeal wall (superior constrictor muscle) constricts, thereby forming a sphincter that separates the nasopharynx and oropharynx.
- Functional Deficits of Speech and Swallowing
- Figure 19-2 Patient with partial glossectomy defect closed primarily. Tongue mobility was deficient. It is not possible for the patient to move the tongue or any food bolus laterally onto the occlusal surfaces of the teeth.
- Anatomic and Physiologic Considerations: Normal Function
- Facial Form
- Loss of Vertical Opening and Altered Mandibular Movements
- Processed Bases
- Border Molding The Velopharyngeal Area: Patient Movements
- Figure 19-3 The conventional obturator trial base (A) has been blocked out at the peripheries of the maxillary resection to allow removal from the master cast. The processed base (B) made from the same master cast allows maximum tissue contact and stability for the arrangement of teeth and jaw relationship records. C, The patient's face is supported marginally with the maxillary edentulous obturator base and dentition but it is undercontoured to minimize the weight of the lip and face grossly unseating the prosthesis. D, Maximum retention can only be assessed with a processed base to optimize facial support at the try-in stage.
- Border Molding Peripheries of Maxillary Resections and Hard Palate Defects: Patient Movements
- Testing The Prosthetic “Seal” Between The Oral Cavity and The Nasal Cavity
- Immediate Surgical Obturator Prosthesis
- Interim Obturator Prosthesis
- Figure 19-4 A, The 2-0 silk sutures are placed through the predrilled holes at the periphery of the obturator, knotted, and tagged with a hemostat before being placed into the mouth and sutured into the patient's vestibule. B, A palatal bone screw in the vomer can be used to retain an edentulous surgical obturator.
- Figure 19-5 The baseplate surgical obturator can be modified at pack removal with an immediate impression of the palate, and then incremental additions of the tissue-conditioning material are made, processed to resin, and delivered the same day.
- Figure 19-6 The acrylic resin interim obturator at follow-up. The defect area will be modified periodically with subtractions and additions of tissue conditioner material.
- Figure 19-7 The patient's original denture has normal anatomical borders (left); however, the obturator prosthesis relined at 4 weeks after surgery (right) has markedly altered contours in the anterior of the prosthesis because of facial contracture. A tray extension over the soft palate into the pharynx was added to support an impression of the pharynx in function, which was necessary because the patient's velar movement was inadequate in the weeks after surgery (see Fig. 19-13).
- Definitive Obturator Prosthesis
- Figure 19-8 A viscous alginate carries into the maxillary defect allowing extension of the custom impression tray.
- Figure 19-9 A, The custom tray should be supported against the residual palate and not displaced into the maxillary defect during the impression procedures. B, The superior aspect of the obturator makes contact with the skin-grafted bone of the pterygoid plates, acting as vertical support. C, The palate is impressed before border molding the defect, allowing stability and a repeatable position of the tray. D, Impression wax is placed over the compound to finalize the impression and denote pressure areas in the compound to cut back and repeat the wax impression. E, The maxillary base should be stabilized by the clinician, as the least stable base, during jaw relationship records.
- Troubleshooting An Obturator Prosthesis
- Lack of Retention
- Figure 19-10 A, Two severely worn teeth were prepared with copings and magnetic attachments. B, The patient wore this prosthesis for 10 years until his death from cardiac arrest.
- Nasal Reflux
- Figure 19-11 A to C, Implant placement at the premaxilla and tuberosity area can greatly improve the retention and stability of the obturator prosthesis for edentulous patients with maxillary resections. Resections this large should be considered for microvascular boney reconstruction.
- Hypernasality
- Figure 19-12 A, This patient had maxillary left gingival cancer and a second mandibular left gingival cancer and periodontal disease. B, She underwent maxillectomy and skin graft, marginal mandibulectomy and skin graft, dental extractions, and immediate implant placement in the maxilla and mandible. She was not irradiated. C to E, She has worn these implant-supported and implant-retained prostheses successfully for 4 years.
- Lack of Retention
- Figure 19-13 A, This patient who underwent a maxillectomy had lack of appropriate velar movement due to radiation fibrosis of the velum occurring approximately 3 years after radiotherapy. A pharyngeal extension was added to the prosthesis extending over the soft palate remnant to obturate the pharynx and correct hypernasality. B, The Passavant's ridge can be seen through the defect of the soft palate.
- Figure 19-14 A, This patient had a resection of squamous cell carcinoma of the soft palate and mandible. The Passavant's ridge on the pharyngeal wall is not evident at rest, but is evident only on phonation (B).
- Figure 19-15 An obturator is added to the denture and formed with functional swallowing and head movements and then is evaluated in speech. The height is usually no more than 1 cm.
- Troubleshooting The Soft Palate Obturator Prosthesis
- Prosthesis Feels Too Long
- Hypernasality
- Clinical Examination
- Informing The Patient
- Marginal Mandibulectomy Prostheses
- Figure 19-16 Tongue sutured to buccal mucosa following hemiglossectomy. The tissue closed primarily over the mandible, precluding fabrication of a stable denture.
- Figure 19-17 This patient had a free soft tissue flap from the forearm placed over a marginal mandibulectomy, replacing missing soft tissue of the floor of the mouth and mandible. The right cast reveals the contour changes after connective tissue debulking 1.5 cm of soft tissue; however, because the flap does not attach to the mandible, the tissue is very mobile, and the patient could not successfully wear dentures.
- Figure 19-18 This patient had a marginal mandibulectomy and floor-of-mouth resection that was reconstructed with a split-thickness skin graft from the thigh. Given the excellent posterior mandibular height and nonmobile tissue in the anterior mandible, the patient did very well wearing conventional dentures.
- Discontinuity Mandibulectomy Prostheses
- Figure 19-19 The deviated discontinuity jaw relationship records should be made with the wax rims making broad contact at the vertical dimension of occlusion. A rigid recording material such as plaster can be injected into notches along the buccal of the wax rims, making a closed-mouth recording of the static centric occlusion contact.
- Troubleshooting Prostheses For The Patient With An Edentulous Mandibulectomy
- Unstable Mandibular Denture
- Inability to Chew or Inability to Chew Beyond a Soft Diet
- Prostheses For Reconstructed Mandibles
- Risks and Benefits Assessment of Implants In Irradiated Tissues
- Figure 19-20 A, This edentulous patient had a mandibular resection, fibula flap, and immediate implants placed in the native remnant mandible at sites 18, 19, and 31, followed by radiotherapy to 60 Gy. B and C, After 2 years of overdenture function, continued horizontal loss of bone occurred at all implant sites and the right implant was lost. After HBO, four implants were placed in the irradiated fibula for better prosthesis stabilization. D and E, The sagittal cone beam reformations reveal the contour of the fibula and its small dimension. Bicortical implant placement is imperative in this bone because of the very fatty marrow and large marrow space.
- Risk of Osteoradionecrosis
- Hyperbaric Oxygen Therapy
- Figure 19-21 This patient was an unsuccessful denture wearer following floor of mouth and tongue resection. He was given HBO after 58 Gy of radiotherapy. Implants were placed in the native mandible. This reveals the tissues at a 5-year follow-up.
- Irradiation of Existing Implants
- Prosthodontic Treatment Considerations For The Irradiated Edentulous Patient
- Timing of Denture Placement
- Figure 19-22 Patient had HBO and extraction of 20 to 29 two months earlier. She has severe radiation-induced mucosal atrophy indicated by telangiectasia. Her xerostomia, mucosal damage, and tongue dysfunction make her a poor candidate for successful mucosal-borne prostheses.
- Salivary Consideration for the Irradiated Edentulous Patient
- Occlusal Forms
- Delivery and Postinsertion Care
- Timing of Denture Placement
- Problems
- TABLE 20-1 POSSIBLE PROBLEMS AND COMPLICATIONS
- Figure 20-1 Far too many implants were crowded into the available maxillary host bone site. This resulted in a lack of adequate access for hygiene maintenance, less than ideal 3-dimensional orientation of the implants’ long axes, and encroachment on mobile buccal gingival tissue (arrow). Moreover, it is clear that a surgical template was not used to reconcile optimal prosthetic teeth placement with implant locations. Furthermore, long cantilever arms would be required here to provide suitable support for prosthetic teeth that would provide an acceptable smile. It also should be noted that such long cantilever extensions associated with implants that have been placed in straight-line configurations, rather than in a preferred semilunar arrangement, are more frequently associated with component fracture.
- Complications
- Surgically Related Complications
- At Stage I Surgery
- Figure 20-2 Extensive bruising is dramatically evident in this patient within a week after she underwent maxillary implant surgery.
- Figure 20-3 A, This Kennedy class IV partially edentulous mandible demonstrates the opening of an incision line following implant placement. The necrosed flap in B is allowed to heal without further intervention (C).
- Interval Between Stage I and Stage II
- Figure 20-4 A dehiscence has occurred in an edentulous mandible that has undergone the first of a two-stage surgical procedure. Management of this occurrence is straightforward and requires overlying denture relief to avoid tissue irritation or “pinching,” together with scrupulous oral hygiene.
- Box 20-1 Recipe for Varnish for Tissue Conditioner
- At Stage II Surgery
- At Stage I Surgery
- Prosthodontic-Related Complications (Table 20-2)
- Abutment Related
- TABLE 20-2 PROSTHODONTIC-RELATED COMPLICATIONS
- Impression Related
- Try-in of Tooth Arrangement
- Framework Try-in
- Abutment Related
- Insertion Of Prosthesis
- Implant-Supported Fixed Prosthesis
- Implant-Supported Overdenture
- Postinsertion
- Biological Complications
- Mechanical/Prosthodontic Complications
- Figure 20-5 The fractured mandibular implant was detected during a routine recall examination. The patient was asymptomatic other than presenting with gingival irritation and bleeding adjacent to the fracture site. The prosthesis was removed and the superior part of the implant unscrewed from the prosthesis and discarded. The undersurface of the prosthesis was smoothed and polished and the access hole sealed. The soft tissue overlying the residual implant material was allowed to heal over. The resultant increased cantilever length can always be reduced depending on an assessment of the occlusal stresses at the site. Two implants were originally placed in the maxilla to support an overdenture, but the right one failed to osseointegrate. The single remaining maxillary implant was successfully osseointegrated and continued to be used as adjunctive support for the prosthesis.
- Figure 20-6 Time-dependent wear and tear take their toll on the integrity of the prosthetic material employed in the fabrication of implant-supported fixed prostheses. It is relatively easy to replace the prosthetic teeth in the case of A, but somewhat more technically challenging to repair the fracture as seen in B. In the latter case, the original design features may have to be reconsidered and a new and stronger framework made. Alternatively, the acrylic resin may be removed and if feasible, a new part soldered to replace the original cantilever. In this case, serious consideration also should be given to a shorter cantilever.
- Surgically Related Complications
- Box 21-1 Requirements to Promote Osseointegration
- Box 21-2 Modifications to Requirements for Osseointegration Allowing Immediate Load
- Immediate Load Complete Denture Technique
- Figure 21-1 Preoperative (A and B) and radiographic (C) images of patient with advanced periodontal disease, missing teeth, dental caries, and defective dental restorations.
- Figure 21-2 A, Placement of four implants in maxillary arch using tipped posterior implants to allow increased implant length and avoid critical anatomical structures (maxillary sinus), as well as increasing the anterior to posterior spread of the implants. B, Connection of implants using transfer components that are attached to implants. The components are connected using 0.048” orthodontic wire that is luted to implants using autopolymerizing resin. C, Try-in of custom tray. Note open window in tray to allow access to retaining screws. D, The impression material flows around the splinted implants and the adjacent tissues.
- Figure 21-3 A, Soft tissue impression with implant analogs in place. B, Application of soft tissue material to impression.
- Figure 21-4 A, Maxillary complete denture with open anterior windows in position of the lateral incisors allows implant transfer components to be rigidly connected to denture base using autopolymerizing resin after the prosthesis is fully seated against the hard palate. B, Close up of luted components. C, Centric relation record made with both prostheses luted in position.
- Figure 21-5 A, Denture with luted transfer components. B, Denture teeth replaced in anterior windows.
- Figure 21-6 Clinical (A) and radiographic (B) images of prostheses and implants in position.
- References
- Systemic Health and Host Bone Response
- Box 22-1 Clinical Yield from Long-Term Prospective Clinical Studies in Osseointegration
- Box 22-2 Research Developments
- Figure 22-1 A selection of clinical treatment examples underscores the expanded scope of implant-supported prosthodontics that evolved from the original edentulous management experience. A, Treatment 1, Long-standing severe localized periodontal disease caused removal of teeth and bone grafting the area. Teeth restored with splinted 12-11 implant-supported crowns after an appropriate healing period. B, Treatment 2, Teeth 22 and 23 were missing for several years. Implants were deliberately submerged to provide vertical space to accommodate a fixed prosthesis in a class 2, division II-type incisal relationship. The provisional prosthesis was worn before the final one (porcelain fused to metal splinted crowns) was inserted. C to E, Treatments 3 to 5 demonstrate fixed and removable implant solutions for mandibular posterior partial edentulism. Routine rehabilitations were achieved irrespective of the associated compromised bone morphology resulting from teeth loss in Treatment 3, an oncological intervention in Treatment 4, or trauma in Treatment 5. F, Treatment 6 addresses prosthetic replacement for the exenterated left orbital contents.
- Box 22-3 Proposed Determinants of Osseointegration Success
- Smoking
- TABLE 22-1 SUMMARY OF INFLUENCE OF VARIOUS FACTORS ON IMPLANT PROSTHODONTIC TREATMENT OUTCOMES: PATIENT-RELATED FACTORS
- Osteoporosis
- Bisphosphonate Therapy
- Irradiation Therapy
- Other Systemic Conditions
- Imaging Protocol
- Figure 22-2 Accurate imaging of the osseous structures permits fabrication of a maxillary surgical stent (A) that is secured intraorally in the predetermined position by means of pins (B) and provides a very accurate guide for implant placement.
- Surgical Protocols
- Figure 22-3 Lekholm-Zarb classification of edentulous anterior jawbone quantity and quality. Types A through E reflect a range of resorptive patterns relative to the presumed demarcation of the alveolar and basal jawbone (dotted line). Quality (Types 1 through 4) reflects a range of cortical and cancellous patterns, which have been consistently used in planning oral implant treatment.
- Bone Quality
- Bone Quantity And Site Improvement
- Prosthodontic Loading
- Figure 22-4 Clinical examples of diverse implant treatment applications that include tilting of implants and the use of diverse-sized ones (A and B) plus zygomatic ones (C to E) to support a fixed maxillary prosthesis.
- Oral Ecological Concerns
- Figure 22-5 Periodontal ligament vs. osseointegrated interface. In the natural dentition (A and B), well-integrated developmental events lead to a structural continuity that is made possible by the periodontal ligament's evolutionary history. In contrast, the structural continuity between osseointegrated implants and their host bone sites (C) results from an induced and controlled wound-healing process that may be influenced by a number of determinants (see Box 22-3).
- TABLE 22-2 SUBTLE, IF PROFOUND, DIFFERENCES BETWEEN TEETH AND IMPLANT ATTACHMENT MECHANISMS DEMAND A DIFFERENT INTERPRETATION OF WHAT INFLUENCES THEIR RESPECTIVE VULNERABILITY TO FAILURE
- Summary
- Bibliography
- Chapter 23 The Impact of Socioeconomic, Cultural, and Technological Changes and the Notion of Standards of Care and Alternative Protocols
- Standards Of Care
- Minimum Acceptable Protocols
- An “Appropriatech” Method For Complete Dentures In Four Clinical Sessions
- Box 23-1 Guidelines for a Minimum Acceptable Protocol for the Construction of Complete Dentures
- Initial Preparatory Phase
- Treatment Phase
- Posttreatment Phase
- First Clinical Session
- Impressions
- Figure 23-1 Protocol-based guidelines conforming to the Minimum Acceptable Protocol (MAP) for a patient-centered approach to treatment. The various colors reflect a range of options but are not themselves indicative of a given option.
- Position of Maxillary Anterior Teeth
- First Laboratory Session
- Impressions
- Second Clinical Session
- Establishing the Vertical Dimension of Occlusion
- Recording the Horizontal Jaw Relationship
- Figure 23-2 Some of the steps in the CD4 technique. A and B, Stock trays modified with peripheral wax. C, First alginate impression being cut back to take a second wash. D, Final upper impression (double alginate) with postdam area marked. E and F, Casts marked for correct extension of the bases (from a single alginate). G, ANTAGs. H, Soft peripheral wax added to ANTAG. I, Some measurements using the ANTAG to determine upper anterior tooth positions. J and K, Bases ready for second visit. L, Jaw relation record. M, Check bite for remounting. N, Balancing contacts. O, Occlusal indicator wax to confirm functional interocclusal contacts. P, Q, and R, Satisfied patients at the recall visit.
- Second Laboratory Session
- Third Clinical Session
- Remount and Occlusal Adjustment
- Counseling the Patient
- Fourth Clinical Session
- Summary
- Box 23-1 Guidelines for a Minimum Acceptable Protocol for the Construction of Complete Dentures
- Reproducing Complete Dentures
- Figure 23-3 Some of the steps in the duplication technique. A, An occlusal record at a new vertical dimension on the existing denture. B, The polished surface of the denture is pressed into alginate in an oversized box tray to form one half of the mold. C, Laboratory putty is pressed into the alveolar surface of the denture and paper clips are used to retain the plaster that reinforces this half of the mold (as seen in D). E and F, The wax replica is removed from the mold and mounted on an articulator. G and H, New acrylic resin teeth replace the wax “teeth” of the replica in the same positions. I, Zinc-oxide-eugenol paste has been used to reline the wax base.
- First Clinical Session
- First Laboratory Session
- Second Clinical Session
- Second Laboratory Session
- Third Clinical Session
- Adaptation And Advancing Technology
- Summary
- References
- Bibliography
- Index
- A
- B
- C
- D
- E
- F
- G
- H
- I
- J
- K
- L
- M
- N
- O
- P
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UM RAFBÆKUR Á HEIMKAUP.IS
Bókahillan þín er þitt svæði og þar eru bækurnar þínar geymdar. Þú kemst í bókahilluna þína hvar og hvenær sem er í tölvu eða snjalltæki. Einfalt og þægilegt!Rafbók til eignar
Rafbók til eignar þarf að hlaða niður á þau tæki sem þú vilt nota innan eins árs frá því bókin er keypt.
Þú kemst í bækurnar hvar sem er
Þú getur nálgast allar raf(skóla)bækurnar þínar á einu augabragði, hvar og hvenær sem er í bókahillunni þinni. Engin taska, enginn kyndill og ekkert vesen (hvað þá yfirvigt).
Auðvelt að fletta og leita
Þú getur flakkað milli síðna og kafla eins og þér hentar best og farið beint í ákveðna kafla úr efnisyfirlitinu. Í leitinni finnur þú orð, kafla eða síður í einum smelli.
Glósur og yfirstrikanir
Þú getur auðkennt textabrot með mismunandi litum og skrifað glósur að vild í rafbókina. Þú getur jafnvel séð glósur og yfirstrikanir hjá bekkjarsystkinum og kennara ef þeir leyfa það. Allt á einum stað.
Hvað viltu sjá? / Þú ræður hvernig síðan lítur út
Þú lagar síðuna að þínum þörfum. Stækkaðu eða minnkaðu myndir og texta með multi-level zoom til að sjá síðuna eins og þér hentar best í þínu námi.
Fleiri góðir kostir
- Þú getur prentað síður úr bókinni (innan þeirra marka sem útgefandinn setur)
- Möguleiki á tengingu við annað stafrænt og gagnvirkt efni, svo sem myndbönd eða spurningar úr efninu
- Auðvelt að afrita og líma efni/texta fyrir t.d. heimaverkefni eða ritgerðir
- Styður tækni sem hjálpar nemendum með sjón- eða heyrnarskerðingu
- Gerð : 208
- Höfundur : 8847
- Útgáfuár : 2012