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91.
AIM: To investigate a number of clinical and treatment variables that might have influenced the prevalence of apical periodontitis in root-filled teeth in a population of periodontally compromised patients. METHODOLOGY: This investigation was a retrospective cross-sectional study on data collected from periodontal charts in addition to intra-oral full-mouth radiographs from patients attending the Department of Periodontology of the Dental School of the Ghent University Hospital. Periodontal parameters (clinical attachment loss and the lowest marginal bone level, the history of periodontal treatment), endodontic treatment (length, homogeneity and overall quality of the root filling) and the quality of coronal restorations were related to the prevalence of apical periodontitis. A total of 272 root-filled teeth in 94 patients were evaluated. RESULTS: The periapical condition was significantly influenced by the quality of the root filling and the coronal filling (P < 0.05). More apical periodontitis was seen when the coronal level of the root filling exceeded the marginal bone level (P < 0.005). The marginal periodontal condition seemed to influence the periapical status. Teeth with apical periodontitis were associated with significantly more extended marginal bone loss (P < 0.001). Significantly less apical periodontitis was seen in patients that had received marginal periodontal treatment (P < 0.005), compared with untreated periodontal patients. CONCLUSIONS: Signs of periodontal disease, as reflected by marginal bone loss, are of importance for the periapical condition of root-filled teeth. Efforts should be taken in preventing spread of infection through the periodontal-endodontic pathway by periodontal infection control and a high quality of root filling and coronal filling. Care should also be taken to seal the coronal cavity up to the level of the root filling, where it is advisable to reduce the coronal level of the root filling below or at least at the level of the surrounding marginal bone.  相似文献   
92.
The aims of this study were to evaluate the clinical outcomes of root canal treatments performed by final-year students in the Dental School of Piracicaba, State University of Campinas, SP, Brazil, during the year 2000 and to evaluate the success rate of these treatments at follow-ups conducted one and three years later (2001-03). All 579 endodontic treatments performed by final-year students were selected for this investigation. Detailed personal and dental history was obtained from the patient's records. Clinical and radiographic follow-up examinations were performed. For 78.8 percent of the cases, dental caries was recorded as the cause for performing endodontic treatment; for 8.8 percent, prosthetic reasons were given; and for 12.4 percent, failure of the endodontic treatment was the reason. The largest percentage (30.7 percent) of recalled patients was examined after one year; the success rate at this follow-up evaluation ranged from 83 percent to 96 percent depending on the pulp status prior to the root canal treatment. After three years, only 8 percent of treated patients returned; assessment for them revealed a 75.5 percent success rate. Dental caries is still the main reason for endodontic treatment. This level of success of the root canal treatment in a Brazilian dental school is similar to other reports in the literature.  相似文献   
93.
94.
目的报道喙突过长引起下颌运动受限、开口困难的病例资料,供临床工作借鉴。方法报道7例喙突过长致开口困难病例的临床、X线表现及治疗方法。结果曲面断层、华特位片可较好的显示突喙突过长,但往往不为临床医师所认识。本资料6例经手术切除过长的喙突后,开口度均恢复正常。结论喙突过长致开口困难较少见,应在开口困难的鉴别中予以注意。  相似文献   
95.
Functional monomers in adhesive systems can improve bonding by enhancing wetting and demineralization, and by chemical bonding to calcium. This study tested the hypothesis that small changes in the chemical structure of functional monomers may improve their bonding effectiveness. Three experimental phosphonate monomers (HAEPA, EAEPA, and MAEPA), with slightly different chemical structures, and 10-MDP (control) were evaluated. Adhesive performance was determined in terms of microtensile bond strength of 4 cements that differed only for the functional monomer. Based on the Adhesion-Decalcification concept, the chemical bonding potential was assessed by atomic absorption spectrophotometry of the dissolution rate of the calcium salt of the functional monomers. High bond strength of the adhesive cement corresponded to low dissolution rate of the calcium salt of the respective functional monomer. The latter is according to the Adhesion-Decalcification concept, suggestive of a high chemical bonding capacity. We conclude that the adhesive performance of an adhesive material depends on the chemical structure of the functional monomer.  相似文献   
96.
There is little knowledge of the number or the work characteristics of dental hygienists outside the private-practice setting. This survey was conducted to determine the percentage of hygienists practicing in nontraditional (nonprivate-practice) settings and the types of settings in which they are employed. Mail questionnaires were returned from a total of 21,847 (56.9%) of the hygienists in the survey sample. The percentage of active hygienists practicing in nontraditional settings was 11.8. Dental or dental hygiene schools, and government and nongovernment-supported clinics were the most frequent nontraditional practice settings. State supervision requirements were found to be associated significantly with the prevalence of nontraditional hygiene practice.  相似文献   
97.
To determine the spatial arrangement of collagen fibrils in articular cartilage of the human mandibular condyle, ten healthy condyles obtained at necropsy were examined by light microscopy and scanning electron microscopy (SEM). Observations using light microscopy showed the existence of four different zones. The organization and alignment of the collagen fibrils were different in every zone and varied from layers to bundles of fibrils running parallel, obliquely, or radially to the articular surface. Observations using scanning electron microscopy revealed a thin, surface layer of disorganized small fibrils with a cotton-wool appearance and a well-organized architecture of collagen fibrils in every zone. It was concluded that the organization of collagen fibrils in articular cartilage shows a three-dimensional network with a special system in every zone.  相似文献   
98.
99.
Three cases of infiltrating congenital lipomatosis of the face are presented. These lesions shared the following morphologic criteria: 1) nonencapsulated congenital fatty tumor; 2) infiltration of adjacent muscle and soft tissue; 3) absence of lipoblast and malignant characteristics; 4) presence of fibrous elements with numerous nerve bundles and vessels; and 5) hypertrophy of subjacent bone. Although these tumors are benign, all three recurred after surgical excision. Extensive specimen sampling is advisable to exclude infiltrating lipoma, diffuse angiomatosis, infiltrating angiolipoma, and well-differentiated liposarcoma. Relationship with lipoblastomatosis and histogenesis of infiltrating congenital lipomatosis of the face are discussed.  相似文献   
100.
Factors Affecting Self-ratings of Oral Health   总被引:1,自引:0,他引:1  
Objectives: The purpose of this study is to determine the relationship of self-rated oral health to a comprehensive battery of clinical, sociodemographic, physical health, and mental health measures in a well-elderly urban population. Methods : Results are based on telephone interviews and clinical assessments of 550 subjects over 65 years of age participating in a Los Angeles-based Medicare project during 1990. Subjects were mostly female, white (89%), with above-average income. Results : Findings show that: (1) the DMF measure is not as strongly related to self-rated oral health as was a single measure of missing teeth; (2) the major predictors of self-rated oral health were "worry about teeth" and "appearance of teeth" followed by total missing teeth, race, education, and depression scores; and (3) self-rated general health is related to self-rated oral health. Conclusion : Self-rated oral health may be, for older adults, a better measure of "health" than of "morbidity."  相似文献   
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