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61.
Mucormycosis of the mandible   总被引:1,自引:0,他引:1  
A case of mucormycosis of the mandible and adjacent soft tissue is presented. The rampant osteomyelitis that developed over a two-month period shows the necessity of early medical and surgical intervention. The management of these patients includes aggressive medical management of underlying problems, high-dose amphotericin B administration, and early surgical debridement of all involved tissues.  相似文献   
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Bacterial adherence to gingival cells was compared in rats with spontaneous gingivitis (SUS rat) and in control rats (RES rat). In the SUS rat, the number of adherent bacteria in gingival cells changed according to the progression of gingival inflammation. There was a correlation between the change of the number of adherent bacteria, progress of inflammation and pH in the pocket. In the RES rat, the number of adherent bacteria was constant and very small. In the adherence assay, adherence of Bacteroides intermedius to epithelial cells was dependent on the pH. Adherence of B. intermedius was better than that of other species. B. gingivalis and B. macacae showed good adherence but B. levii showed poor adherence. Adherence to the epithelial cells of the SUS rat was always better than that of the RES rat. These results were supported by scanning electron microscopic studies.  相似文献   
64.
The purpose of the present work was to assess the adequacy and effectiveness of a public dental program for old-age pensioners. The dental care program offered free consultation and treatment at reduced prices to all pensioners (3072) in a municipality near Oslo in 1979. To study treatment need and access to dental care, a random sample of 430 pensioners was drawn from the total population of old-age pensioners; 371 persons were clinically examined. Of the 3072 old-age pensioners 23.7% responded positively and indicated that they were interested in the program, whereas 19.8% accepted, and 14.6% had the treatment carried out. The program adequacy was low and became lower when more restricted criteria for access to dental services were used. The program effectiveness was 18% or 16%, depending on which criteria were used for access. Acceptance of the program was highest among people who were aware of it, had natural teeth, had a dental problem, did not have their own dentist, had limited education, or were among the young pensioners.  相似文献   
65.
AIM: The objectives of the present study were to evaluate and compare the clinical behavior of resin modified glass ionomer cement (RMGIC) on primary molars with conventional and modified cavity preparations. METHODS AND MATERIALS: Forty-two children, 5-9 years of age, having bilateral initial occlusal caries on the mandibular primary second molars were selected for the study. A split mouth design was employed where conventional Class I cavities with a 90 degrees cavosurface angle were prepared randomly on primary second molars on one side and modified cavities with a 1 mm straight bevel along the cavosurface margin on the contra-lateral side. These cavities were restored with RMGIC. The restorations were evaluated during subsequent visits, for a period of one year. RESULTS: At the end of one year, 90% of the restorations survived in the conventional cavity group whereas 100% of the restorations survived in the modified cavity group. CONCLUSION: Incorporation of a bevel in Class I cavities increases the survival rate of RMGIC restorations. There was no significant difference in the clinical behavior between the two groups. However, beveling does contribute to long term clinical success of these restorations. CLINICAL SIGNIFICANCE: Incorporation of a straight bevel in conventional cavities will improve the retention of RMGIC by increasing the bonding area and enhancing the desired properties of the material.  相似文献   
66.
This prospective longitudinal study assessed the 3D soft tissue changes following mandibular advancement surgery. Cranial base registration was performed for superimposition of virtual models built from cone beam computed tomography (CBCT) volumes. Displacements at the soft and hard tissue chin (n = 20), lower incisors and lower lip (n = 21) were computed for presurgery to splint removal (4-6-week surgical outcome), presurgery to 1 year postsurgery (1-year surgical outcome), and splint removal to 1 year postsurgery (postsurgical adaptation). Qualitative evaluations of color maps illustrated the surgical changes and postsurgical adaptations, but only the lower lip showed statistically significant postsurgical adaptations. Soft and hard tissue chin changes were significantly correlated for each of the intervals evaluated: presurgery to splint removal (r = 0.92), presurgery to 1 year postsurgery (r = 0.86), and splint removal to 1 year postsurgery (r = 0.77). A statistically significant correlation between lower incisor and lower lip was found only between presurgery and 1 year postsurgery (r = 0.55). At 1 year after surgery, 31% of the lower lip changes were explained by changes in the lower incisor position while 73% of the soft tissue chin changes were explained by the hard chin. This study suggests that 3D soft tissue response to mandibular advancement surgery is markedly variable.  相似文献   
67.
Background: Recent studies in animals have shown pronounced resorption of buccal bone plate after immediate implantation. The sectioning of experimental material for histologic evaluation of the bone plates could provide valuable information about the possible effect of bone exposure in periodontal and implant surgeries. Methods: Twenty‐four incisors were collected from dogs. After decalcification, the blocks were immersed in paraffin and bucco‐lingual histologic sections were examined under light microscope. Some sections were reserved for immunohistochemical analysis. Results: The bone density, the width of the bone plates, and the percentage of vessels presented in the periodontal ligament and periosteum were analyzed in the buccal and lingual bone plates, which were divided corono‐apically into thirds. The buccal bone plates showed statistically higher bone density compared to the lingual bone plates in the coronal thirds. The width of both bone plates increased from the coronal to the apical third, but all the buccal thirds were significantly thinner compared to the lingual thirds. No statistically significant differences were found between the bone plates for the percentage of area occupied by the blood vessels in the periodontal ligament or periosteum. Conclusion: It is reasonable to conclude that the higher bone density, represented by the lower number of marrow spaces, in association with the thinner aspect of the buccal bone plates made them more fragile to absorb compared to the lingual bone plates, especially during mucoperiosteal procedures.  相似文献   
68.
Kimura disease (KD) is a rare entity that occurs primarily in Asian people characterized histopathologically by a lymph-folliculoid granuloma with infiltration of the mass and the surrounding tissues by eosinophils, often with concomitant peripheral blood eosinophilia and elevated serum immunoglobulin E, generally seen in the head and neck region, especially preauricular area. In this article, we present the case of a 14-year-old male patient with KD on his left parotid area. The clinical, radiologic, surgical, and pathologic findings of KD are discussed in this article.  相似文献   
69.
70.
Cerebrovascular accident (CVA) is the third cause of death in industrialized countries, following cardiovascular disease and cancer. It is therefore a significant public health issue, not only due to its high incidence, but also to the high costs involved in the physical and psychological rehabilitation of these patients. Dental Practitioners, as health care providers, ought to play their part in this issue and contribute, within their means, to the early detection of patients at risk of having a CVA. Since the eighties, different authors have described the possibility of detecting calcified atheroma plaques located at carotid artery bifurcation through panoramic radiograph. In this way, the Dental Practitioner s possibilities in this field have been extended. However, this new use of panoramic radiograph must overcome certain obstacles before it is implemented as a new screening method for patients at risk of having a CVA. Amongst these, we would have, on the one hand, the assessment of the real clinical significance, as regards prognosis, of atheroma plaque calcification as well as its usefulness as a factor for predicting the appearance of CVA symptoms and, on the other hand, the possibility of making a correct differential diagnosis regarding other calcified structures that may appear on panoramic radiograph.  相似文献   
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