Current opinion in dentistry最新文献

During the past year, studies have been completed to advance our knowledge of the diagnosis and treatment of the edentulous patient. The need for pretreatment radiographs on every edentulous patient is not always indicated. Advances in preprosthetic surgery help to improve the predictability of these procedures. New techniques for establishing the vertical dimension of occlusion may allow this to become a more objective measurement. Evaluation of dental materials for use with complete dentures continues, with soft liners and the use of microwave energy for curing denture resin just two areas of interest. A recent study showed a very high prevalence of signs and symptoms of craniomandibular disorders among complete denture wearers. Methods for its treatment are discussed. The use of increased infection control procedures in the dental office and laboratory have created a need to evaluate the effects of disinfecting agents on the dental prosthesis. The removable complete denture remains an effective alternative for the replacement of missing teeth.

Over the last 25 years, the advent of new disciplines in dental education and the increasing body of knowledge in various dental specialties have led to a struggle for curriculum hours within many dental schools. At the same time, the amount of time available for teaching clinical skills in dental schools has not increased appreciably, and fewer patients require (or can afford) sophisticated prosthodontic treatment. As a result of these trends, there has been a general decline in the depth and range of clinical skills of recent dental school graduates, particularly in prosthodontics. New York University College of Dentistry has attempted to address this problem by establishing a predoctoral honors program in prosthodontics.

Pulpal and periapical problems are often difficult to diagnose because of seemingly conflicting or unclear symptoms. This difficulty increases when there is an emergency situation, and improper diagnosis can lead to improper treatment, causing distress to both the patient and clinician. Because the histopathologic condition of the pulp cannot be determined with clinical means or other diagnostic data, the clinician should focus on making an accurate clinical diagnosis using the patient's history and description of pain, clinical examination, and various diagnostic tests. This review discusses these factors and stresses the importance of making an accurate diagnosis.

Despite the good appearance and biocompatibility of dental porcelains, failures are still of considerable concern because of some limited properties common to all-ceramic crown systems. As in the years before, pertinent scientific articles published between November 1990 and December 1991 focused on strengthening mechanisms and compared fracture toughness for different ceramic systems by using various test methods. Some evaluated the clinical implications thereon for seating and loading crowns and measured wear against different ceramic surface conditions. Recently introduced with pleasing aesthetic qualities, IPS-Empress (Ivoclar, Schaan, Liechtenstein), a new European leucite-reinforced glass-ceramic, has finally drawn attention in some journals and has been reviewed with promising in vitro test results. Using a simple press-molding technique, well-fitting crowns, inlays, and veneers can be fabricated without an additional ceramming procedure. Again, only long-term clinical trials will validate achievements compared with other all-ceramic systems and with well-established metal ceramics.

This review covers recent literature on prosthodontic aspects of osseointegrated implants. Long-term prognosis, diagnosis and treatment planning, and clinical impression techniques and fabrication technology are discussed.

Technical improvements in endodontic instruments, materials, and drugs and the development of new techniques for their application present a problem for dental practitioners in the selection of materials and methods appropriate to their needs. Claims of "superior" products and "state-of-the-art" treatments only add to the confusion. A review of the dental literature reveals that there is seldom a consensus of opinion on any given subject. Preferences among individuals may reflect a desire for a less complicated, more rapid approach to endodontic treatment. Trends in thought among researchers may offer some direction in the choice between changing concepts and traditional methodology.

Important features to consider when selecting composite resins are filler size and amount, radiopacity, and fluoride content. Submicron particles provide the best polishability, and heavily filled resins demonstrate better wear resistance. The radiopacity of the composite resin should slightly exceed that of enamel to allow visualization of the restoration and recurrent decay. Fluoride added to the matrix may arrest the progression of caries. Properly cured composite resins should not cause chronic pulpal irritation; however, infection of the cervical contraction gap resulting from poor bonding to root surfaces may cause pulpal irritation. Techniques to improve curing include incremental build-up, reflective matrices and wedges, and controlling the direction of light vectors. A surface sealant is highly recommended to reduce wear, especially in the posterior region. Porcelain veneers perform better clinically than do composite-resin veneers. Class I and II composite-resin restorations reinforce weakened tooth structure; however, problems with cervical leakage and wear prevent the recommendation of these materials for larger posterior restorations that involve occlusal contacts or that require bonding to root surfaces.

Many studies indicate a strong association of Actinobacillus actinomycetemcomitans with localized juvenile periodontitis. Species associated with adult periodontitis include Bacteroides forsythus, Porphyromonas gingivalis, Prevotella intermedia, A. actinomycetemcomitans, and Wolinella recta. Capnocytophaga species may be important in pubertal gingivitis. An unnamed spirochete related to Treponema pallidum has been identified in acute necrotizing ulcerative gingivitis lesions. Species isolated from prepubertal periodontitis, peri-implantitis, pericoronitis, and human immunodeficiency virus gingivitis and periodontitis are similar to those isolated from periodontal and gingival infections. Species identification in combination with clinical characteristics facilitates periodontal diagnosis. DNA probes, immunoassays, and benzoyl-arginine naphthylamide reactivity methods can be used to indicate putative pathogens in plaque samples. Microbial identification aids in antibiotic selection and planning a treatment regimen.