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991.
992.
993.
The objective of this investigation was to examine the dentofacial features of a group of patients with hypodontia, in particular assessing whether cephalometric analysis confirmed the clinical assumption of a reduced lower face height, and to determine the relationship of these facial features with different numbers of missing teeth. It took the form of a cephalometric study, undertaken in a dedicated Dental Hospital clinic for patients with hypodontia. The study group comprised 59 patients seen on the Hypodontia Clinic: 32 females, 27 males, mean age 13.1+/-3.1 years (range 6-23 years). The average number of missing teeth was 7 (SD 5), ranging from 1 to 21. The mean SNA, SNB, and MMA angles were within normal limits, but there was a statistically significant reduction in the MMA when more than one tooth type was missing (P = 0.007) and the ANB angle decreased as the number of missing tooth types increased (P = 0.034). The mean values for the whole sample were within the normal range and did not demonstrate any feature specific to the group, but patients with more severe hypodontia showed tendencies to a Class III skeletal relationship and a reduced maxillary-mandibular planes angle.  相似文献   
994.
995.
BACKGROUND: The prevalence of gingival overgrowth induced by chronic medication with calcium channel blockers is uncertain. Although there have been several studies examining this question, the results are conflicting, with previous estimates ranging from 20% to 83%. There have been only 2 studies examining the prevalence of overgrowth induced by diltiazem and amlodipine, with estimates of 74% and 3.3%, respectively. METHODS: The current study aimed to address the problems associated with these studies by examining a sample of patients taking one of 3 calcium channel blockers, who were drawn from a community-based population in northeastern England. Nine hundred eleven (911) subjects were recruited from general medical practices in the area. Of these, 442 were taking nifedipine, 181 amlodipine, and 186 diltiazem. In addition, 102 control subjects were examined. Drug and demographic data for each subject were recorded. The periodontal condition of all subjects was assessed including plaque index, papillary bleeding index, and a photograph of the anterior gingivae for subsequent analysis of overgrowth severity. RESULTS: More than six percent (6.3%) of subjects taking nifedipine were seen to have significant overgrowth. This overgrowth was statistically greater than the amount of overgrowth seen in either of the other 2 drug groups or the control population. The prevalence of gingival overgrowth induced by amlodipine or diltiazem was not statistically significant when compared to the control group. The severity of overgrowth within the nifedipine group was found to be related to the amount of gingival inflammation and also to the gender of the subject, with males being 3 times as likely to develop overgrowth than females. CONCLUSIONS: The prevalence of clinically significant overgrowth related to chronic medication with calcium channel blockers is low, i.e., 6.3% for nifedipine. Males are 3 times as likely as females to develop clinically significant overgrowth. The presence of gingival inflammation is an important cofactor for the expression of this effect.  相似文献   
996.
A female patient with hypocalcification type amelogenesis imperfecta in permanent dentition in association with heavily worn primary teeth, gingival hyperplasia, hypodontia and impacted teeth is presented.  相似文献   
997.
Oral asaccharolytic Eubacterium species are associated with periodontal disease and other oral infections. The aim of this study was to use a culture-independent molecular technique to determine the diversity of asaccharolytic Eubacterium species in subgingival plaque in periodontitis. An oligonucleotide PCR primer designed to amplify 16S rRNA genes of the oral asaccharolytic Eubacterium branch of the phylogenetic tree was constructed. This primer was used together with a universal primer in PCRs to amplify gene sequences directly from a single subgingival plaque sample. Fifty PCR products were purified by cloning, fully sequenced and subjected to molecular phylogenetic analysis. The sequences were assigned to four groups within a single lineage of the low G + C gram-positive bacteria. Group I (58% of the cloned sequences) was assigned to a branch that included Eubacterium nodatum, and Group II (22%) to a branch including Eubacterium infirmum. Group III (8%) was distinct from but related to E. infirmum at the species level, and Group IV (12%) was another novel taxon more distantly related to E. infirmum and E. nodatum.  相似文献   
998.
A 3-dimensional bone-implant finite element model was created. The objective was to further investigate the mechanical environment of cortical bone adjacent to the threads of a retromolar endosseous implant used for orthodontic anchorage to mesially translate mandibular molars in response to normal functional loading. This study emphasizes the stress invariants around and between the threads of the implant for future comparison to histomorphometric data from an ongoing clinical study. A strong stress pattern change was found immediately around the implant, which was reflected by a moderate change of stresses between the threads and a significant increase in stress at the tips of the threads.  相似文献   
999.
OBJECTIVE: Fibroblastic proliferations of the oral cavity are extremely varied, yet they share certain features-spindle cell morphology, collagen synthesis, and fasciculation. Nodular fasciitis is a cellular fibroblastic lesion, uncommonly located in the oral submucosa, that shows smooth muscle actin (SMA) immunoreactivity. Solitary fibrous tumor expresses a CD34 fibroblast phenotype. The aim of this study is to report instances of nodular fasciitis and solitary fibrous tumor in the orofacial region and investigate immunohistochemical markers to compare and contrast fibroblastic phenotypic heterogeneity in these tumors. STUDY DESIGN: Seven benign cellular fibrogenic tumors initially diagnosed as nodular fasciitis over a 10-year period were examined. Immunohistochemical markers, including S-100 protein, SMA, CD68, CD34, and vimentin, were used to further characterize these lesions. RESULTS: All tumors occurred in adults, and the buccal mucosa was found to be the favored site. The spindle cells in these tumors showed phenotypic heterogeneity both within and between tumors. All were vimentin-reactive and harbored small populations of CD68-positive macrophage/dendrocytes. Five tumors were SMA-positive and CD34-negative; the tumor in one case was SMA-negative and CD34-positive, and that in another was SMA-positive and CD34-positive. CONCLUSION: Although rare, nodular fasciitis and solitary fibrous tumor arise in oral submucosa, usually in the cheek. The histopathologic features and immunomarkers indicative of myofibroblastic differentiation are seen in nodular fasciitis, whereas solitary fibrous tumor is CD34-positive; however, one instance was found to be positive for both markers. All of these cases harbored subpopulations of CD68-positive cells. Immunomarkers are a valuable adjunct in differentiating nodular fasciitis from solitary fibrous tumor, yet some tumors may harbor heterogeneous fibroblast phenotypes.  相似文献   
1000.
Two elderly edentulous patients with the diagnosis of early stage cancer of the upper gingiva were treated by customized dental mold brachytherapy. Locoregional tumor control was achieved in both patients. One patient is alive without any evidence of disease 36 months after treatment, the other patient died of distant metastasis shortly after brachytherapy. Brachytherapy, being easy to apply with short treatment time and good acute tolerance, is a good choice and effective modality for the management of early stage gingival cancer, particularly in elderly patients.  相似文献   
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