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81.
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OBJECTIVE: Little is known about the effects of social and biological risk factors for open bite on the primary dentition. The aim of this study was to assess the early-life risk factors affecting anterior open bite. METHODS: A cross-sectional study using a birth cohort was carried out in Pelotas, Brazil. A sample of 400, 6-year-old children was employed. The Foster and Hamilton criteria were used to classify open bite. Data concerning social conditions, and perinatal and childhood health and behaviour were obtained from birth to 12 months of age and during the fifth year of the children's lives. Unconditional bivariate and multiple logistic regression analysis were performed. RESULTS: The prevalence of anterior open bite was 46.3%. Risk factors included: a maternal age of between 30 and 39 years, as compared with children whose mothers were younger; breast-feeding for < 9 months; dental caries experience; pacifier sucking between 12 months and 5 years, as compared to no sucking or a shorter duration of sucking; and the presence of finger-sucking at 6 years of age. CONCLUSION: Open bite in the primary dentition was associated with older mothers, early weaning, dental caries occurrence, long-term use of a pacifier and finger-sucking at 6 years of age. These findings support the common risk approach for intervention to prevent open bite in the primary dentition.  相似文献   
83.
This study evaluated the time, occurrence of fracture, and quality of apical cavity preparation with three different ultrasonic diamond tips: Satelec, Trinity, and a new type, CVD (chemical vapor deposition), using scanning electron microscopy (SEM) analysis. Thirty human single-rooted premolars were selected, submitted to apicectomy, and prepared with ultrasonic tips; impressions were then obtained. The presence of fractures was evaluated on the impressions, and the quality of preparation was evaluated by SEM analysis of teeth and scoring by two examiners. The group prepared with the CVD tips exhibited the shorter preparation time and did not present fractures. There was no statistically significant difference in the quality of preparation for the three tips. The three brands of ultrasonic tips produced adequate grinding without altering the morphology of the apical foramen.  相似文献   
84.
AIM: To investigate in individuals with symptomatic dental abscesses the occurrence of functional polymorphisms within five genes involved with the immune response. The functional gene polymorphisms analysed were CD14 (-260 C/T), IL1B (+3954 C/T), IL6 (-174 G/C,), IL10 (-1082 G/A) and TNFA (-308 G/A). METHODOLOGY: Genomic DNA obtained from oral swabs from individuals with symptomatic dental abscesses and asymptomatic inflammatory periapical lesions, without previous exacerbation, was submitted to restriction fragment length polymorphism (RFLP) analyses to determine each individual genotype. The chi-square and principal components analysis tests were used for statistical analysis. RESULTS: A significant association was observed between the occurrence of the GG genotype or the G allele expression of the polymorphic locus-174 (G/C) of the IL6 gene, and the presence of the symptomatic dental abscesses in women and in individuals < or =35 years old. The principal components analysis suggested predominance of the symptomatic dental abscesses in individuals displaying: high-producer IL6 genotype; intermediate and high-producer IL1B genotypes and low-producer TNFA genotype. CONCLUSIONS: The present study suggests that genetic factors are associated with susceptibility to develop symptomatic dental abscesses.  相似文献   
85.
AIM: The aim of this article is to present a case of Paracoccidioidomycosis with involvement of the oral cavity but without pulmonary manifestations. BACKGROUND: Paracoccidioidomycosis is a fungal infection caused by Paracoccidioides brasiliensis. It is an endemic disease representing a serious health problem for Latin American countries, especially Brazil. This infection primarily affects the lungs of adult men and is acquired through inhalation or accidental inoculation of the fungus. It can spread to other organs and tissues, mainly the oral cavity. Administration of antifungal medication always resolves the disease. REPORT: A 58-year-old black male presented with three painless, ulcerated, mulberry-like granulomatous lesions located in the floor of the mouth, on the superior alveolar ridge, and on the hard palate, which had evolved over a period of two years. Facial asymmetry was observed due to edema in the lower lip and lymphadenopathy. He had smoked for more than six years but showed no evidence of lung alterations, productive cough, or fever. Panoramic radiography showed no signs of a bone lesion in the jaws. Both a radiograph and a CT scan of the thorax showed no areas of nodular infiltration. Fibrobronchoscopic examination of the entire respiratory tract was normal. Biopsies of the oral lesions were performed, and tissue sections exhibited oral mucosa coated with non-keratinized stratified squamous epithelium with acanthosis and focal areas of exocytosis. The underlying connective tissue showed an intense lymphocytic and polymorphonuclear infiltrate in addition to multinuclear giant cells and coagulation necrosis. A special stain used for fungus (the Grocott-Gomori method) was positive. Pulmonary biopsy exhibited aerial spaces containing macrophages, dark granular hemossiderin, and absence of fungus. This was considered normal. In agreement with the recommendation of pneumologists 400 mg/day of ketoconazole was prescribed for the patient. After two months of treatment, even though the oral lesions had resolved completely, the therapy was maintained for six months more. One year after following treatment the patient was in good health and free of any signs of a recurrent infection. SUMMARY: Based on clinical, radiographic, and histologic findings the differential diagnosis included paracoccidioidomycosis and squamous cell carcinoma. Following clinical and biopsy examinations of the oral lesions and the lungs a final diagnosis of paracoccidioidomycosis was made. This is a prime example of oral manifestations of a systemic disease in which the dentist is the initial health care professional to evaluate the patient due to the location of the lesions.  相似文献   
86.
87.
An inadequate fit at the abutment/implant interface can generate mechanical and biological problems. The laboratorial stages could induce misfit in such interface when the castable UCLA abutment type is used. The purpose of this study was to comparatively evaluate the performance of three prosthetic laboratories (Labs A, B and C) by vertical fit analysis of castable UCLA abutments on the casting and soldering stages of the same prosthesis. Four fixed prostheses were built by each laboratory using castable UCLA abutments. The evaluation was made by scanning electron microscopy under 500x magnification in the mesial and distal regions of each element of the prosthesis, totalizing 24 measurements per laboratory. The results were analyzed statistically by Kruskal-Wallis test (p<0.05). In the casting process, the values presented by the laboratories differed significantly to each other (p=0.004). After soldering, the values presented by the laboratories showed no significant difference (p=0.948). It may be concluded that the fit values obtained in the casting stage of UCLA abutments can be influenced when processed by different laboratories, and that conventional soldering itself increased the degree of framework misfit, regardless of which laboratory made it.  相似文献   
88.

Objective

The aim of this study was to determine the salivary levels of dehydroepiandrosterone (DHEA) and cortisol and scores of depression, anxiety and stress in patients with oral lichen planus (OLP).

Study design

Thirty-one patients with a diagnosis of OLP were selected; they were matched by sex and age with 31 control patients. Symptoms of depression, anxiety and stress were investigated by the instruments Beck Depression Inventory, Beck Anxiety Inventory and Lipp's Inventory of Stress Symptoms for Adults, respectively. Saliva was collected in the morning and at night for the determination of DHEA and cortisol levels by radioimmunoassay.

Results

There was no significant difference between the groups with respect to depression (P = 0.832), anxiety (P = 0.061) or stress (P = 0.611), or with respect to morning and night salivary levels of DHEA (P = 0.888, P = 0.297) and cortisol (P = 0.443, P = 0.983).

Conclusions

The results suggest an association of OLP with anxiety. However, DHEA and cortisol levels did not differ between groups, which does not support any neuroendocrine aetiology for OLP.  相似文献   
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90.
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