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41.
Service-learning has become an important component of higher education. Integrating service-learning into dental and dental hygiene curricula will foster graduates who are better prepared to work effectively among diverse populations and to function dynamically in the health policy arena. Although the phrase is familiar to dental educators, there is not a consistent understanding of what comprises this pedagogy. This article offers a framework for service-learning in dental education and describes ten components that characterize true service-learning. This framework can provide a common understanding of this form of experiential education that brings community engagement and educational objectives together. More effective programs can be built around a shared understanding of the characteristics and goals of service-learning in dental education.  相似文献   
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PURPOSE: The purpose of this study was to survey members of The American College of Prosthodontists (ACP) to evaluate current materials and methods for final impressions for complete denture prosthodontics in the United States. In addition, those methods were compared with methods and materials taught in U.S. dental schools via a second survey sent to the chairpersons of prosthodontic/restorative departments. MATERIALS AND METHODS: An anonymous questionnaire was mailed to all 1762 active ACP members in the United States in 2003. A slightly modified questionnaire was also distributed to chairpersons of prosthodontic/restorative departments in the 54 U.S. dental schools. Data analysis was performed via frequency distribution and chi-square statistics. RESULTS: Nine hundred and forty-five questionnaires were returned by members of the ACP (54% return rate) and 42 questionnaires were returned by the U.S. dental schools (78% return rate). The majority of the reporting prosthodontists (88%) and dental schools (98%) use a border-molded custom tray for final impressions for complete denture prosthodontics. The most popular material for border molding was plastic modeling compound (67% of reporting ACP members, and 95% of the responding dental schools). Variability of the materials used for final impressions was observed, with the most popular materials being polyvinylsiloxane for the ACP members (36%) and polysulfide for the dental schools (64%). Statistically significant differences were found in the materials used for border molding by prosthodontists based on the time elapsed since completion of prosthodontic training. No differences were found in the materials used for impression of edentulous arches based on years of experience. Geographic location did not influence the materials and methods used by prosthodontists for complete denture final impressions. CONCLUSIONS: There was variability of the materials and techniques used for final impressions by ACP members and dental schools; however, overall there was an agreement on the materials and techniques used by prosthodontists and dental schools. Distinct trends for increasing use of polyvinylsiloxane and polyether for border molding procedures and impressions of edentulous arches were observed both in members of the ACP and in the U.S. dental schools.  相似文献   
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Lichen planus is a dermatologic disease of unknown etiology characterized by keratotic plaques on the skin. Many patients also harbor white lesions of the oral mucosa. The literature contains numerous reports of lichen planus-like lesions evolving in conjunction with the administration of a variety of pharmacologic agents. It is difficult, if not impossible, to distinguish such lesions from one another. The present study evaluated the epithelial and basement membrane thickness, mast cells (intact cells and degranulated cells subepithelially) and the presence or absence of blood vessels in oral lichen planus and oral lichenoid lesions. The evaluation was done using the periodic acid-schiff (PAS) and toluidine blue staining techniques on 20 cases each of oral lichen planus and oral lichenoid lesions and 5 control specimens of normal buccal mucosa. The results showed an increased number of degranulated mast cells in areas of basement membrane degeneration, increased vascularity and increased PAS-positive basement membrane thickness in oral lichen planus as compared with oral lichenoid lesions. Reduced epithelial thickness was found in oral lichen planus. The present study emphasizes the importance of these parameters in differentiating oral lichen planus from oral lichenoid lesions using special staining techniques.  相似文献   
46.
Chondrosarcoma is a malignant cartilaginous tumor that rarely occurs in the maxillofacial bones. A 44-year-old woman complained about swelling and mild pain during mastication in the right parasymphysis region. Clinical and radiographic examinations revealed characteristics of osteosarcoma. A microscopic examination revealed an abundant proliferation of malignant neoplastic cartilage cells of varying sizes arranged as immature tissue and the absence of an osteoid matrix. This article presents a case of chondrosarcoma of the jaw and discusses the differences between osteosarcoma and chondrosarcoma.  相似文献   
47.
Background.  Dental caries continues to be the most common infectious disease of childhood; however, it is no longer pandemic, but endemic in specific sectors of populations. Therefore, it is important to identify and target patients at risk of developing caries in order to develop specific preventive measures.
Aim.  This study aims to test dental caries risk indicators for significant associations with caries severity.
Design.  Five separate, small, isolated rural villages in Mexico with varying degrees of caries prevalence were selected for this observational study. A total of 248 children were examined. Risk indicators were assessed via questionnaire and water and salt fluoride analysis. Caries severity was measured by the International Caries Detection and Assessment System (ICDAS-I).
Results.  Prevalence of caries ranged from 95% to 100% for the five villages. Mean total DMFS (decayed, missing, or filled surfaces–permanent teeth) and dmfs (decayed, missing, or filled surfaces–primary teeth) scores ranged from 2.5 to 5.0 and from 11.3 to 16.9, respectively. Multivariable models showed age and drinking soda between meals to be significantly associated with DMFS, and drinking juice and being female were significantly associated with dmfs.
Conclusion.  DMFS and dmfs were high in each village, significantly different between villages, and associated with specific risk indicators.  相似文献   
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Myoclonus is a brief, rapid, involuntary muscle jerk originating in the central nervous system that can be physiological or a symptom of disease. We report a group of five children with excessive myoclonic jerks, only during sleep, and abnormal EEG during the events. Although only one third of the events had EEG epileptiform correlate, the presence of myoclonus without epileptiform EEG correlate has been described in patients with benign myoclonic epilepsy of infancy. We hypothesize that these findings may represent a variant of benign myoclonic epilepsy of infancy.  相似文献   
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