Current opinion in dentistry最新文献

The literature on the subject of aesthetic partial-coverage restorations, including laminate veneers, laminate veneer bridges, composite-resin and ceramic inlays and onlays, computer-designed restorations, and etched cast restorations, has continued to expand into the 1990s. Investigations regarding fit, longevity, wear, and microleakage, as well as descriptions of clinical techniques, were well documented world-wide in 1991. The purpose of this review is to discuss some of the more important papers published during the past year.

This review discusses the multifactorial nature of tooth strength and concludes that endodontic treatment alone does not weaken intact anterior teeth. Therefore, restoration of such teeth does require post placement or full-coverage restorations. Posterior teeth, however, require full-coverage protection. It appears that the full-crown restoration "covers up" some of the disadvantages or deficiencies of some post and core restorations. The literature supports the use of the amalgam coronal-radicular core or the post-retained amalgam core, as well as the composite post and core. The literature does not support use of the glass ionomer post and cores. As to which post system to select, the literature indicates that the parallel-sided, serrated Para-Post or Para-Post plus is a safe post when seated passively in the canal and cemented with zinc phosphate cements or composite resin cement, or when retained with amalgam. Dentin-retained, stress-producing posts such as the threaded posts should be avoided.

At least 1000 CAD/CAM (computer-aided design and computer-aided manufacturing) systems for producing restorations are in dental offices. At least nine different systems have been described; the Cerec system (Siemens, Bensheim, FRG) is the best known and most widely used. Clinical results to date suggest that the automated CAD/CAM systems can provide restorations which perform at least as well as cast restorations. There are some technique sensitivities that must be managed with the new technology. The importance of fit at the margins is a controversial issue that remains to be settled. Bond strength of composite-luted restorations is dependent on margin location and luting material properties, and on the combination of silanating, etching, and curing mechanism of the luting composite. Surface finishes equivalent to cast gold and glazed porcelain can be achieved for machinable CAD/CAM materials.

This review on dose reduction in dental radiography focuses on criteria for selecting the frequency and type of radiographs to be performed on patients. By making radiographs only when there is a reasonable probability of a finding that will influence patient care, patient exposure and other radiographic costs may be substantially reduced. Patient dose may also be reduced by half by changing from D-speed film to E-speed film for intraoral radiography and by more than half by changing from calcium tungstate intensifying screens to rare-earth intensifying screens for panoramic and cephalometric radiography. Using rectangular collimation for intraoral radiography will also further reduce patient exposure by about fourfold. Finally, the use of time-temperature processing will prevent overexposure of the patient and underprocessing of the radiographs; optimal radiographs will be provided.

The field of occlusion continues to be prolific in publications. While no major advancement in the field was noted in the 1-year period of review, existing concepts and instrumentation continued to be refined. Topics covered in this review include occlusal tooth contacts, choice of alternate occlusal schemes, evaluation of gnathologic instruments and techniques, vertical dimension of occlusion, and mandibular flexure eliminate occurring on opening.

This paper reviews the pulpal response to common restorative procedures and dental materials. Pulpal inflammation and dentin hypersensitivity are commonly associated with routine restorative procedures. Although it is not possible to avoid injury to the pulp completely, in order to prevent unnecessary adverse effects, the practicing dentist should be aware of the potential dangers involved. This article provides a current review of recent findings of the pulpal response to glass ionomer cements and acid-etch composite resin materials.

Successful treatment of traumatic injuries depends on timely action by the patient and a quick and accurate diagnosis by the dentist. Although most injuries are minor and of an urgent nature, displaced or missing teeth are true emergencies. The mismanagement of dental traumatic injuries has provided much information as well as questions for research that have resulted in the increased retention of teeth with as little treatment as possible. Maintaining pulp vitality when possible, utilizing the therapeutic effects of calcium hydroxide, and returning teeth to function as soon as possible are keys to predictable prognosis.

Surgical procedures for the prosthodontic patient have advanced greatly over the last decade. Both the aesthetics and function of the final restoration can be greatly enhanced by various surgical procedures. Some are very predictable, and others are still in the developmental stages. This review is divided into three basic categories: aesthetic root coverage; crown lengthening; and ridge augmentation procedures.