Conditioned fear stress increases bone resorption in apical periodontitislesions in Wistar male rats.

OBJECTIVE: Because the impact of conditioned fear stress on apical bone resorption is unknown, the aim of the current studywas to use a rat model to evaluate the impact of conditioned fear stress on the bone resorption of inflammatory apical periodontitis lesions. METHODS: Twenty-five animals were divided into two groups. They underwent a surgical procedure in the first left lower molar tooth to expose the dental pulp and induce inflammatory apical periodontitis lesions through the retention of contamination (bacterial infection) during a 56-day period. The animals in the case group were stressed daily by using electrical stimuli (1.10 mA), whereas the animals in the control group were absent from the stressful stimuli (shocks). The open field test was performed to validate the stress methodology. The jaws were removed and collected for histological and radiographic analyses. RESULTS: Stressed animals presented increased levels of bone loss and inflammatory cells in the root apex in comparison with the control group (P = 0.0001). However, no radiographic differences were observed between the groups (P > 0.05). CONCLUSIONS: Our results demonstrated that conditioned fear stress could modify a periapical lesion by increasing the size of bone loss there. Conditioned fear stress also increased the total number of inflammatory cells compared with the control group. Studies evaluating the impact of conditioned fear stress on human periapical inflammatory lesions should be encouraged.

Prevalence of oral mucosal lesions in a brazilian military police population.

BACKGROUND: Data obtained from oral health surveys are very important for identifying disease-susceptible groups and for developing dental care and prevention programs. So, the purpose of the current article was to investigate the prevalence of oral mucosa lesions (OMLs) in a population of Brazilian police. MATERIAL AND METHODS: Interviews and oral cavity examinations were performed on a sample of 395 police officers who were randomly selected by the calibrated researcher. The number of individuals was obtained by a sample calculation using the finite population correction. The diagnostic criteria were based on the WHO (1997) criteria and adapted to Brazilian surveys. RESULTS: In total, 8.61% of the population presented some OML. Traumatic injuries and benign migratory glossitis (BMG) were the most prevalent lesions. CONCLUSIONS: The prevalence of potentially malignant disorders was lower than among the Brazilian population.The most prevalent lesion among the police officers was related to trauma. Patients dissatisfied with oral health had a higher risk of presenting OMLs. Key words:Mouth disease, mouth mucosa, military personnel, public health, oral pathology, oral leukoplakia.

Low expression of MSH2 DNA repair protein is associated with poor prognosis in head and neck squamous cell carcinoma

OBJECTIVE: This study aimed to investigate the expression of the MSH2 DNA repair protein in head and neck squamous cell carcinoma (HNSCC) in order to analyze its association with clinicopathologic factors and overall survival of patients. MATERIAL AND METHODS: Clinical data and primary lesions of HNSSC were collected from 55 patients who underwent surgical resection with postoperative radiotherapy in Montes Claros, state of Minas Gerais, Brazil, between 2000 and 2008. Immunohistochemical reactions were performed to analyze MSH2 protein expression. RESULTS: Bivariate analysis showed no significant correlation or association between MSH2 expression and clinicopathologic parameters by Mann-Whitney and Kruskal-Wallis tests. Patients with locoregional metastatic disease (OR=4.949, p<0.001) and lower MSH2 immunohistochemical expressions (OR=2.943, p=0.032) presented poorer survival for HNSCC by Cox regression models. CONCLUSIONS: Our data demonstrated that lower MSH2 expression might contribute to a higher clinic aggressiveness of HNSCC by promoting an unfavorable outcome. .