Effect of the root canal final rinse protocols on the debris and smear layer removal and on the push-out strength of an epoxy-based sealer

The aim of the present study was to evaluate the efficacy of QMiX, SmearClear, and 17% EDTA for the debris and smear layer removal from the root canal and its effects on the push-out bond strength of an epoxy-based sealer by scanning electron microscopy (SEM). Forty extracted human canines (n = 10) were assigned to the following final rinse protocols: G1-distilled water (control), G2–17% EDTA, G3-SmearClear, and G4-QMiX. The specimens were submitted to a SEM analysis to evaluate the presence of debris and smear layer, respectively, in the apical or cervical segments. In sequence, forty extracted human maxillary canines with the root canals instrumented were divided into four groups (n = 10) similar to the SEM analysis study. After the filling with AH Plus, the roots were transversally sectioned to obtain dentinal slices. The specimens were submitted to a push-out bond strength test using an electromechanical testing machine. The statistical analysis for the SEM and push-out bond strength studies were performed using the Kruskal–Wallis and Dunn tests (α = 5%). There was no difference among the G2, G3, and G4 efficacy in removing the debris and smear layer (P > 0.05). The efficacy of these groups was superior to the control group. The push-out bond strength values of G2, G3, and G4 were superior to the control group. The ability to remove the debris and smear layer by SmearClear and QMiX was as effective as the 17% EDTA. The final rinse with these solutions promoted similar push-out bond strength values.

In situ effect of chewing gum containing CPP–ACP on the mineral precipitation of eroded bovine enamel

Objectives: Stimulation of salivary flow is considered a preventive strategy for dental erosion. Alternatively, products containing calcium phosphate, such as a complex of casein phosphopeptide–amorphous calcium phosphate (CPP–ACP), have also been tested against dental erosion. Therefore, this in situ study analyzed the effect of chewing gum containing CPP–ACP on the mineral precipitation of initial bovine enamel erosion lesions. Methods: Twelve healthy adult subjects wore palatal appliances with two eroded bovine enamel samples. The erosion lesions were produced by immersion in 0.1% citric acid (pH 2.5) for 7 min. During three experimental crossover in situ phases (1 day each), the subjects chewed a type of gum, 3 times for 30 min, in each phase: with CPP–ACP (trident total), without CPP–ACP (trident), and no chewing gum (control). The Knoop surface microhardness was measured at baseline, after erosion in vitro and the mineral precipitation in situ. The differences in the degree of mineral precipitation were analyzed using repeated measures (RM-) ANOVA and post hoc Tukey’s test ( p < 0.05). Results: Significant differences were found among the remineralizing treatments ( p < 0.0001). Chewing gum (19% of microhardness recovery) improved the mineral precipitation compared to control (10%) and the addition of CPP–ACP into the gum promoted the best mineral precipitation effect (30%). Conclusions: Under this protocol, CPP–ACP chewing gum improved the mineral precipitation of eroded enamel. Clinical significance: Since the prevalence of dental erosion is steadily increasing, CPP–ACP chewing gum might be an important strategy to reduce th eprogression of initial erosion lesions.

Tratamento de lodo de ETA em ETE por sistema de lodo ativado operando em MBBR

Apresentação em evento

Conhecimento médico sobre as imunodeficiências primárias na cidade de São Paulo, Brasil

OBJETIVO: Avaliar o conhecimento médico sobre as imunodeficiências primárias na cidade de São Paulo (SP). MÉTODOS: Um questionário de 14 questões sobre as imunodeficiências primárias foi aplicado a médicos que trabalhavam em hospitais gerais. Uma das questões apresentava 25 situações clínicas que poderiam ou não estar associadas às imunodeficiências primárias, e a porcentagem de respostas apropriadas gerou um indicador de conhecimento. RESULTADOS: Participaram do estudo 746 médicos, dentre os quais 215 pediatras (28,8%), 244 cirurgiões (32,7%) e 287 clínicos (38,5%). Cerca de 70% dos médicos responderam ter aprendido sobre as imunodeficiências primárias na graduação ou na residência médica. O atendimento a pacientes que usam antibióticos com frequência foi relatado por 75% dos médicos, mas apenas 34,1% já haviam investigado algum paciente e 77,8% não conheciam os dez sinais de alerta para as imunodeficiências primárias. O indicador de conhecimento obtido apresentou uma média de 45,72% (±17,87). Apenas 26,6% dos pediatras e 6,6% tanto dos clínicos quanto dos cirurgiões apresentaram indicador de conhecimento de pelo menos 67% (equivalente à resposta apropriada em dois terços das situações clínicas). CONCLUSÃO: Há uma deficiência no conhecimento médico das imunodeficiências primárias na cidade de São Paulo, mesmo entre os pediatras, a despeito do maior contato com o tema nos últimos anos. A melhora da informação sobre as imunodeficiências primárias entre a comunidade médica é um importante passo para o diagnóstico e o tratamento precoces dessas doenças.