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551.
552.

Objectives

The purpose of this study was to evaluate the prevalence of alveolar bone loss (BL) in healthy children treated at private pediatric dentistry clinics in Brasília, Brazil.

Material and Methods

The research included 7,436 sites present in 885 radiographs from 450 children. The BL prevalence was estimated by measuring the distance from the cementoenamel junction (CEJ) to alveolar bone crest (ABC). Data were divided in groups: (I) No BL: distance from CEJ to ABC is ≤2 mm; (II) questionable BL (QBL): distance from CEJ to ABC is >2 and <3 mm; (III) definite BL (DBL): distance from CEJ to ABC ≥3 mm. Data were treated by the chi-square nonparametric test and Fisher''s exact test (p<0.05).

Results

Among males, 89.31% were classified in group I, 9.82% were classified in group II and 0.85% in group III. Among females, 93.05%, 6.48% and 0.46% patients were classified in Group I, II and III, respectively. The differences between genders were not statistically significant (Chi-square test, p = 0.375). Group composition according to patients’ age showed that 91.11% of individuals were classified as group I, 8.22% in group II and 0.67% in group III. The differences among the age ranges were not statistically significant (Chi-square test, p = 0.418). The mesial and distal sites showed a higher prevalence of BL in the jaw, QBL (89.80%) and DBL (79.40%), and no significant difference was observed in the distribution of QBL (Fisher’s exact test p = 0.311) and DBL (Fisher’s exact test p = 0.672) in the dental arches. The distal sites exhibited higher prevalence of both QBL (77.56%) and DBL (58.82%).

Conclusions

The periodontal status of children should never be underestimated because BL occurs even in healthy populations, although in a lower frequency.  相似文献   
553.
 

Aim:


To evaluate the cytokeratin pattern of expression of hyalinizing trabecular adenomas and to verify whether or not these tumours, that share morphological features with papillary carcinomas, present the stratified epithelial-type cytokeratins commonly found in ordinary papillary carcinomas.  

Methods and results:


This study consisted of the immunohistochemical detection of simple and stratified epithelial type cytokeratin filaments in a series of six hyalinizing trabecular adenomas, three papillary carcinomas with a trabecular growth pattern and two carcinomas combining hyalinizing trabecular and papillary patterns. Simple epithelial-type cytokeratins 7, 8, 18 and 19 were found in every case. Expression of the stratified epithelial-type cytokeratins 1, 5/6 and/or 13 was detected in four hyalinizing trabecular adenomas.  

Conclusion:


Based on this, as well as on the cytological features and on the frequent co-occurrence of hyalinizing trabecular adenoma and papillary carcinoma, we suggest that the former lesion may be considered a peculiar encapsulated variant of papillary carcinoma.  相似文献   
554.

Background

Computed tomography is currently the gold standard for the diagnosis of chronic rhinosinusitis. However, this facility is not readily available in many developing countries. Thus, plain sinus radiography is still widely in use in our practice.

Objectives

To assess the diagnostic value of plain radiographs in adult patients with uncomplicated chronic maxillary rhinosinusitis.

Methods

This study was carried out at a tertiary health facility in Northern Nigeria. All adult patients with clinical and radiological diagnosis of chronic maxillary rhinosinusitis were included.

Results

A total of 88 patients were recruited into the study. There were 51 males (58.0%) and 37 (42.0%) females. Their ages ranged from 18 to 60 years; with a mean age of 31.7±9.20 years. Mucosal thickening was the commonest diagnostic plain radiographic feature, and fluid level was the least. Maxillary antra with diagnostic plain radiographic interpretations of fluid level, haziness and opacity had high specificities (100%, 95.2%, and 85.7%) and high positive predictive values (100%, 75%, and 70%) respectively.

Conclusions

Plain radiographs are relevant in the diagnosis of chronic maxillary rhinosinusitis in our locality only when they show features of fluid level: findings of haziness and opacity are of less diagnostic value.  相似文献   
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