Relationship between fluoride exposure and count of Streptococcus mutans in supragingival biofilm of mexican scholar children.

BACKGROUND/PURPOSE: The use of fluoride is known to reduce the risk of dental caries. There is limited information on the relationship between Streptococcus mutans (S. mutans) and fluoride exposure. This study investigated the association between the count of S. mutans on supragingival biofilm and fluoride exposure of scholar children. MATERIALS AND METHODS: In this cross-sectional study, 56 children from 9 to 11 years of age were selected. Fluoride concentration in drinking water, urine and saliva of each participant were assessed. The count of S. mutans was estimated by calculating the DNA copy number through a quantitative real time polymerase chain reaction (qPCR) assay. Also, sociodemographic data, oral and general health information and variables related to caries risk were evaluated. A stepwise multiple linear regression was performed in all caries related predictor variables with the count of S. mutans as the dependent variable. RESULTS: The multiple linear regression analysis showed that the concentration of fluoride in saliva (ß = -3.029, p < 0.001) and urine (ß = -2.057, p = 0.017), time of last visit to the dentist (ß = 1.968, p = 0.001), plaque index (ß = 1.637, p = 0.006) and number of surfaces with codes 3-6 (D3-6MFS) of ICDAS II criteria (ß = 0.283, p = 0.076) were significantly associated with the count of S. mutans (Adjusted R square = 0.427, p < 0.001). CONCLUSION: Fluoride levels in urine and saliva were negatively associated with the count of S. mutans in supragingival biofilm. Plaque index, D3-6MFS and time of last visit to the dentist showed a positive association.

Congenital lingual cyst: Expression of MUC protein and report of a new case.

Lingual congenital cysts are uncommon lesions that alter the functions of speech, swallowing and breathing when they have considerable dimension. They usually appear from birth and increase in size gradually in childhood and adolescence. While there are a considerable number of case reports, the nomenclature and origin of this lesion are controversial. Congenital lingual cysts are composed of an epithelial lining that can show heterogeneous histological features, such as globed, ciliated, squamous and parietal cells, while the wall presents mature connective tissue and eventually smooth muscle. In the present manuscript, we report a case of a congenital lingual cyst in a 13-year-old boy, as well as the immunoexpression of MUC family proteins (MUC-1 and MUC-5AC), hoping to provide data that will help to clarify the possible etiology of this lesion.

Clinical, histological and immunohistochemical findings in oral Kaposi's sarcoma in a series of Mexican AIDS patients. Comparative study.

BACKGROUND: The origin of spindle cells (SC) in oral Kaposi's sarcoma (OKS) is still an intriguing aspect. Thus the aim of the present study was to compare the clinical, histological and immunohistochemical characteristics of OKS and oral pyogenic granuloma (OPG), in order to contribute to the knowledge of the cells involved in Kaposi's sarcoma pathogenesis. METHODS: In this retrospective, observational and comparative study, 39 OKS and 30 OPG cases were included. Immunohistochemical studies were performed for vimentin, alpha SMA, desmin, C-kit, CD34, D2-40 and LANA-1 [human herpesvirus-8(HHV-8)]. Statistical comparisons were done using the chi-square and Wilcoxon-Mann-Whitney rank sum tests. RESULTS: Fourteen (35.9%) OKS cases also affected the skin, and 83.8% involved the palate. All OKS and OPG were positive for vimentin and CD34. OKS samples were positive for alpha SMA, and 25.6% expressed C-kit. All OKS cases were positive for HHV-8, and the number of positive cells increased significantly from early / intermediate to late histological stage. D2-40 was expressed in the cellular component and vascular walls of all OKS cases, but it was negative in OPG. HHV-8 expression was increased in late histological stages of OKS lesions. CONCLUSIONS: The expression of D2-40 marker in the vascular walls and SC supports the view of a lymphatic differentiation in neoplastic cells of OKS. Desmin, alpha SMA, D2-40, C-kit and HHV-8 were the main markers differently expressed in OKS and OPG.