Current opinion in dentistry最新文献

Successful endodontics begins with accurate diagnosis. A systematic routine must be followed to obtain the information necessary to arrive at the correct diagnosis. This paper discusses the role of the patient's medical history, as well as subjective, objective, and radiographic examinations in the diagnostic process with special emphasis on information published within the past year.

Leukoplakia is the only important precancerous lesion of the mouth. The epidemiology of oral leukoplakia has been well established in white adults in the United States. There is a hole in the epidemiologic literature, however, on leukoplakia in American minority populations. Recent literature has begun to address the issue of the pathophysiology of leukoplakia, its causes and treatment, and predicting its malignant transformation. Computerized image analysis, retinoid compounds, beta-carotene, and laser surgery are contributing to advances in these lines of research. Though leukoplakia is often seen in patients who use smokeless tobacco products, it is usually benign and reversible if use of the tobacco product is discontinued. The direction of current research in leukoplakia studies eventually should lead to an understanding of the nature and cure of this ubiquitous lesion.

The way in which cells communicate with each other is fundamentally important for developing and maintaining normal tissue structure and function. In order to get a better understanding of cell adhesion, researchers have long been trying to identify and characterize chemical structures at the cell surface that might participate in, or mediate, cell-cell and cell-matrix adhesion. During the last decade, this has led to the identification of a number of cell-surface adhesion proteins and their ligands, which may be either proteins or carbohydrates. The LEC cell-adhesion molecule family is a group of cell-adhesion molecules with a lectinlike domain. They bind to carbohydrate structures, some of which have been identified on dendritic cells in oral epithelium. LEC cell-adhesion molecules are found on endothelial cells during inflammation and may, in such situations, be involved in the recruiting of dendritic and other inflammatory cells, thereby playing a role in the regulation of inflammatory reactions in the oral mucosa. The integrin family is another group of cell-surface adhesion molecules recently identified in oral mucosa that participate in cell-matrix and cell-cell adhesion in many important processes including wound healing, immunodefense mechanisms, and oncogenic transformation. Knowledge of the distribution of cell-adhesion molecules and their ligands and of the mechanism that controls their expression is, therefore, of great importance in understanding of the development of disease in the oral mucosa.

During the period covered by this issue, over 500 papers were published in the area of biology of dental hard tissues. This review is limited to publications that focus on the organic matrix components believed to be important in the formation of dentin, cementum, and enamel. The advances made in this area for the collagen-based dental hard tissues (dentin and cementum) have been primarily in the isolation and partial characterization of the noncollagenous proteins such as proteoglycans, phosphoproteins, and proteins normally found in bone. These proteins are being studied because of their potential role for directing hydroxyapatite nucleation or crystal growth. The progress made in the enamel field has been primarily in the area of molecular biology. Enamel is quite different physically from dentin and cementum because it is formed from a noncollagenous matrix (mostly amelogenin), which is almost completely removed and replaced with hydroxyapatite. Serum proteins have now been found in all dental hard tissues including enamel. Opinions on the clinical significance of these advances are provided.

Oral microorganisms, either directly or indirectly, produce the majority of cases of pulpal and periapical disease. Because microorganisms play such an important role in the pathogenesis of pulpal and periapical disease, a fundamental understanding of the disease process is important. Culture studies have identified infections of endodontic origin as being polymicrobial and predominantly anaerobic. Although several species of bacteria have been associated with infections of endodontic origin, there is no absolute correlation with signs and symptoms. The use of immunologic studies in addition to traditional microbiologic studies provides a better understanding of the mechanisms involved in the pathogenesis of pulpal and periapical disease.

Endodontic emergencies include situations of pain or swelling that require the immediate attention of a dentist. These emergencies interrupt the schedule of the patient and the dental team. This article reviews the clinical conditions that might require emergency therapy, etiologies of these conditions, and the minimal treatment needed to alleviate the signs and symptoms. Current opinions on these issues are presented.

This article reviews the recent literature on endodontic surgery and root end filling materials. Root end filling materials have been studied extensively during the period of this review. The materials that have proved to consistently seal the apex in both leakage and success studies are the reinforced zinc oxide-eugenol cements such as IRM (The L.D. Caulk Co., Milford, DE) and SuperEBA (Harry J. Bosworth Co., Skokie, IL) cement. Articles on treatment planning and surgical armamentaria are also reviewed. Two textbooks and 21 journal articles are cited.

During the past year, few articles have been published regarding the various aspects of oral lichen planus. The work reported dealt with a variety of aspects including patient profile, immunopathogenesis, and treatment. The papers served to confirm previous concepts of an immunologic etiology, the demographic consensus on patient profiles, and the use of topical or systemic corticosteroids as the most effective treatment approach. This review also summarizes some highlights of previous studies of oral lichen planus prior to 1990 and summarizes a current unpublished prospective study reflecting the findings in a large number of patients with oral lichen planus who have been followed for a long period of time.

This review focuses on compatible materials that are either implanted in bone tissue to serve as prosthetic devices or used as bone substitutes. It attempts to evaluate the significance of studies of combined osteoconductive materials with osteoinductive factors, like demineralized bone or its purified components, and osteogenic cells. It is important to note that the term osseointegration, which is still widely used by clinicians to indicate the bioactivity of implants in bone healing, is not substantiated by any controlled basic study. Even pure titanium and hydroxyapatite can interfere with the normal healing of a surgical bone wound. This review emphasizes the three-dimensional structure of bone, intercellular communication, and the response of this system to bone damage and materials.