Revisiting rigid overdenture design following traditional removable prosthetic concepts: a case report.

The inability to place a sufficient number of implants posteriorly may limit tooth and soft tissue replacement because of the cantilever effects that would result from the unsupported prosthesis. Fabrication of a fixed removable overdenture that is implant retained and supported by both implants and soft tissue allows adequate replacement of teeth and soft tissue for optimal mastication and esthetics. This case report describes a design for implant overdentures that conforms to fundamental removable prosthetic principles by using a rigid bar with bilateral locking passive attachments. The rigid implant overdenture provides extra retention via the locking attachments while maintaining stability with proper extensions and full soft tissue support posteriorly. This removable implant overdenture design is a suitable treatment option for patients who desire the sensation of a fixed prosthesis but are unable to receive fully implant-supported prostheses.

Radiological and micro-computed tomography analysis of the bone at dental implants inserted 2, 3 and 4 mm apart in a minipig model with platform switching incorporated.

BACKGROUND: The purpose of this study was to assess the effect of inter-implant distance on interproximal bone utilizing platform switching. Analysis of interproximal bone usually depends on traditional two-dimensional radiographic assessment. Although there has been increased reliability of current techniques, there has been an inability to track bone level changes over time and in three dimensions. Micro-CT has provided three-dimensional imaging that can be used in conjunction with traditional two-dimensional radiographic techniques. METHODS: This study was performed on 24 female minipigs. Twelve animals received three implants with an inter-implant distance of 3 mm on one side of the mandible and another three implants on the contra-lateral side, where the implants were placed 2 mm apart creating a split mouth design. Twelve other animals received three implants with an inter-implant distance of 3 mm on one side of the mandible and another three implants on the contra-lateral side, where the implants were placed 4 mm apart creating a split mouth design too. The quantitative evaluation was performed comparatively on radiographs taken at t 0 (immediately after implantation) and at t 8 weeks (after termination). The samples were scanned by micro-computed tomography (µCT) to quantify the first bone to implant contact (fBIC) and bone volume/total volume (BV/TV). Mixed model regressions using the nonparametric Brunner-Langer method were used to determine the effect of inter-implant distance on the measured outcomes. RESULTS: The change in bone level was determined using radiography and its mean was 0.05 mm for an inter-implant distance of 3 and 0.00 mm for a 2 mm distance (P = 0.7268). The mean of this outcome was 0.18 mm for the 3 mm and for 4 mm inter-implant distance (P = 0.9500). Micro-computed tomography showed that the fBIC was always located above the reference, 0.27 and 0.20 mm for the comparison of 2-3 mm (P = 0.4622) and 0.49 and 0.34 mm for the inter-implant distance of 3 and 4 mm (P = 0.1699). BV/TV inside the defined parallelepipedic masks reached 82.38% for the 2 mm inter-implant distance and 85.00% for 3 mm, P = 0.8432. For the comparison of the 3-4 mm inter-implant distance, the means were 84.69% and 84.38%, respectively, P = 0.8401. Non-inferiority tests for the smaller inter-implant distances for both comparisons showed similar differences and similar tolerance ranges. CONCLUSION: The effect of a smaller interproximal distances between implants on bone level, fBIC and BV/TV assessed by two convergent investigation methods, radiology and µCT, was similar to that of larger distances. Implants can potentially be placed 2 mm apart instead of 3 mm and 3 mm apart instead of 4 mm when platform switching is utilized. Further research with a conventional platform is warranted.

Effect of 3- and 4-mm interimplant distances on the height of interimplant bone crest: a histomorphometric evaluation measured on bone level dental implants in minipig.

PURPOSE: To analyze crestal bone loss changes that may affect the gingival height around an implant and bone loss in interproximal areas. When implants are placed adjacent to one another, interimplant bone loss around 1 implant may combine with the implant bone loss around the adjacent implant to affect the crestal bone loss interproximally. MATERIALS AND METHODS: The primary objective of this study was to evaluate histologically and histomorphometrically the effect that this implant design with a horizontally displaced implant-abutment junction has on the height of the crest of bone, between adjacent implants separated by 2 different distances: 4 mm and 3 mm. A secondary objective was to evaluate the percentage of bone-to-implant contact, interproximal soft tissue height, location of the junctional epithelium, and length of connective tissue contact to abutment and/or implant, for the 2 different distances. RESULTS: Results showed that the interproximal bone loss measured from the edge of the implant platform to the bone crest was not different for interimplant distances of 4 or 3 mm. In addition, the secondary objective parameters also demonstrated similar results between the 2 interimplant distances. CONCLUSION: This study showed that interimplant bone levels can usually be maintained at similar levels for 4- and 3-mm distances during at least 2 months.

Conservative Esthetic Replacement of a Missing Anterior Tooth Using Monolithic Zirconia One-Wing Fixed Dental Prosthesis.

Advances in materials and adhesion technologies have enabled innovative, minimally invasive treatment for replacement of missing maxillary anterior teeth. In the first of two case reports presented, the treatment of a 17-year-old female patient with a missing right central incisor is described. The patient had internal resorption of tooth No. 8, which needed to be extracted prior to a LeFort osteotomy because retention of the tooth may have compromised the healing. The patient was told she could not have an implant placed until she was 25 years old. Treatment options, thus, included a provisional removable appliance (flipper), an Essix appliance, or a resin-bonded one-wing zirconia bridge with only slight modification to the left central incisor. The second case report describes an adult male patient who had had a deciduous canine extracted and wanted a replacement for missing No. 11. In demonstrating minimally invasive treatment to replace a missing maxillary anterior tooth, this article shows how the use of a graded zirconia wing allows bonding with conventional techniques.

The Interplay of Orthodontics, Periodontics, and Restorative Dentistry to Achieve Aesthetic and Functional Success.

Previously dentists focused on repair and maintenance of function. However, the emphasis of many patients and dentists is now on esthetics. Often there is a need for the disciplines of orthodontics, periodontics, restorative dentistry, and maxillofacial surgery to work together in order to achieve optimum results. Currently the sequencing planning process begins with esthetics and then function, structure, and ultimately biology.

Tissue Healing Around Dental Implants With Marginal Bone Defects With and Without Flap Elevation: An Experimental Study in Dogs.

The technique of immediate implant placement after extraction has been conceived for preserving residual bone support and soft tissue morphology. Today, this procedure is still unpredictable and presents inconveniences for both the patient and the dentist. Therefore, the healing process around a dental implant placed into an extraction socket needs to be deeply investigated to increase the predictability of this surgical approach. The aim of the present investigation was to evaluate the healing of bone defects (fresh extraction sockets) after implant installation with flap elevation, and primary closure compared with implant installation without flap elevation. This study use histologic and histomorphometric analyses to evaluate tissue healing around dental implants with marginal bone defects with and without flap elevation 1 week, 4 weeks, and 12 weeks after implantation in the dogs. The main qualitative findings showed that after 1 week of implantation almost no bone repair was observed, and there was no significant difference between the 2 groups in terms of bone-healing performance, inflammatory infiltrates (slight to moderate grade), and bone resorption (moderate to marked grade) limited to the coronal portion of the implanted sites. The 2 groups with or without flap elevation behaved similarly at this point of implantation. Under the experimental conditions of this study, no biological differences were observed between the 2 groups with and without flap elevation in terms of crestal bone repair, inflammation, marginal bone loss, and soft tissue downgrowth. The qualitative differences observed might be imputable to fortuitous events. The histomorphometric measurements confirmed the qualitative trends observed. The limitations of this study, as with all animal studies, are its translational aspects. Investigation of the same topic in a human population by setting up a controlled, randomized, prospective trial including a sufficient amount of patients investigated according to the split-mouth method would be beneficial.

Treatment of the Patient with Gummy Smile in Conjunction with Digital Smile Approach.

Gummy smile cases are always esthetically demanding cases. This article presents a case treated with an interdisciplinary treatment approach and Digital Smile Approach (DSA) using Keynote (DSA), to predictably achieve an esthetic outcome for a patient with gummy smile. The importance of using questionnaires and checklists to facilitate the gathering of diagnostic data cannot be overemphasized. The acquired data must then be transferred to the design of the final restorations. The use of digital smile design has emerged as a powerful tool in cosmetic dentistry to help both practitioner and patient visualize the final outcome.

Complex single-tooth restorations.

There are many options for restoring the decimated dentition. [43] Excellent results can be obtained with many of the materials currently available. The restorative option will depend on the size and location of the lesion, adequate isolation for adhesive restorations, caries rate, the patient's age, the aesthetic needs of the patient, occlusal habits, maintenance of maximum tooth structure, the skill of the dentist, and the longevity desired for the restoration. Amalgam is a cost-effective material, and when used properly, it can provide many years of service. Aesthetic demands, the desire to strengthen teeth, [44] and concern about the safety of mercury in amalgam have increased the use of direct composites, ceramic material, and indirect composites. The main drawback with these materials, however, is their increased technique sensitivity and concerns about their longevity. Gold continues to be a cost-effective and predictable material if placed properly. Full-coverage gold or porcelain fused to metal provides long-term predictability but is more destructive and not as aesthetically appealing. The wide varieties of materials available provide both a challenge and an opportunity to place the most effective material for a particular patient. A thorough understanding of the available materials and their appropriate use is needed to achieve a long-lasting restoration that serves the patient's needs.

Restoration of endodontically treated teeth: criteria and technique considerations.

The restoration of endodontically treated teeth is often required and may represent a challenge as there is no consensus on ideal treatment. The failure of endodontically treated teeth is usually not a consequence of endodontic treatment, but inadequate restorative therapy or periodontal reasons. Prior to the initiation of endodontic treatment the restorability, occlusal function, periodontal health, biologic width, and crown-to-root ratio need to be assessed. If acceptable, the appropriate technique, material, and type of restoration to restore function need to be considered. Posts are used to provide retention for the core material and to replace missing tooth structure. The residual amount of tooth structure will determine its stability for restoration. The creation of adequate ferrule (approaching 2 mm circumferentially is ideal) minimizes the damaging effects of lateral and rotational forces on the restoration and post.

Dentin hypersensitivity: differential diagnosis, tests, and etiology.

Dentin hypersensitivity (DHS) is a painful condition that affects up to 57 percent of the adult population. It occurs as a result of exposure of dentin to the oral environment. Ensuring the correct diagnosis of this condition is based on history and examination. An oral screening for DHS should encompass such elements as patient history, clinical examination that includes radiographs, a variety of tests, identification of risk factors, and a differential diagnosis. An understanding of dentinal fluid and odontoblasts is also beneficial for diagnosis.

Esthetic and functional consideration in restoring endodontically treated teeth.

The selection of the best restoration for an endodontically treated tooth in the aesthetic zone depends on strength and the ability to recreate the form, function, and aesthetics of the natural tooth. The increased use of all-ceramic materials is a result of improved ceramic materials and adhesive systems. However, the advent of the current variety of translucent ceramic systems makes the shade of the abutment important in achieving the desired aesthetic outcome. This article discusses the different types of posts used in the restoration.

Treatment of dentin hypersensitivity.

Dentinal hypersensitivity is exemplified by brief, sharp, well-localized pain in response to thermal, evaporative, tactile, osmotic, or chemical stimuli that cannot be ascribed to any other form of dental defect or pathology. Pulpal pain is usually more prolonged, dull, aching, and poorly localized and lasts longer than the applied stimulus. Up to 30% of adults have dentinal hypersensitivity at some time. Current techniques for treatment may be only transient in nature and results are not always predictable. Two methods of treatment of dentin hypersensitivity are tubular occlusion and blockage of nerve activity. A differential diagnosis needs to be accomplished before any treatment.

Effect of interimplant distance (2 and 3 mm) on the height of interimplant bone crest: a histomorphometric evaluation.

BACKGROUND: Implants restored according to a platform-switching concept (implant abutment interface with a reduced diameter relative to the implant platform diameter) present less crestal bone loss than implants restored with a standard protocol. When implants are placed adjacent to one another, this bone loss may combine through overlapping, thereby causing loss of the interproximal height of bone and papilla. The present study compares the effects of two interimplant distances (2 and 3 mm) on bone maintenance when bone-level implants with platform-switching are used. METHODS: This study evaluates marginal bone level preservation and soft tissue quality around a bone-level implant after 2 months of healing in minipig mandibles. The primary objective is to evaluate histologically and histomorphometrically the affect that an implant design with a horizontally displaced implant-abutment junction has on the height of the crest of bone, between adjacent implants separated by two different distances. RESULTS: Results show that the interproximal bone loss measured from the edge of the implant platform to the bone crest was not different for interimplant distances of 2 or 3 mm. The horizontal position of the bone relative to the microgap on platform level (horizontal component of crestal bone loss) was 0.31 ± 0.3 mm for the 2-mm interimplant distance and 0.57 ± 0.51 mm above the platform 8 weeks after implantation for the 3-mm interimplant distance. CONCLUSIONS: This study shows that interimplant bone levels can be maintained at similar levels for 2- and 3-mm distances. The horizontally displaced implant-abutment junction provided for a more coronal position of the first point of bone-implant contact. The study reveals a smaller horizontal component at the crest of bone than has been reported for non-horizontally displaced implant-abutment junctions.

Dental color matching instruments and systems. Review of clinical and research aspects.

OBJECTIVES: To review current status of hand held systems for tooth color matching in vivo and corresponding research. SOURCES: "Medline" database from 1981 to 2010 were searched electronically with key words tooth, teeth, color and dentistry. CONCLUSION: Spectrophotometers, colorimeters and imaging systems are useful and relevant tools for tooth color measurement and analysis, and for quality control of color reproduction. Different measurement devices either measure the complete tooth surface providing a "color map" or an "average" color of the limited area [3-5mm] on the tooth surface. These instruments are useful tools in color analysis for direct or indirect restorations, communication for indirect restorations, reproduction and verification of shade. Whenever possible, both instrumental and visual color matching method should be used, as they complement each other and can lead towards predictable esthetic outcome.