The aim of this study was to evaluate the effects of irradiance, light emission wavelength, and heating of different light curing units on the Knoop and Vickers hardness of a hybrid composite resin. The specimens were irradiated during 40 s with ten different light curing units, LEDs, and halogen lights. The spectral emission of each light curing unit was assessed by a spectrometer, the irradiance was measured by two commercial radiometers, and the heating measured with a thermocouple. After 48 h of storage in a dark recipient under a 100% humidity condition, the Knoop and Vickers hardness tests were carried out. The hardness results were analyzed by ANOVA, and Tukey HSD test (p < 0.05). The results showed that the surface hardness of the composite resin depends not only on the irradiance, but strongly on the emission wavelength and heating of the light curing units. It was observed, a linear correlation between the conversion degree and radiant exposure. In addition, it is suggested that the well known base to top surface hardness ratio convention of 80-90% is not appropriate to evaluate curing efficiency of composites, since the top surface is not always sufficiently polymerized.

Recently, mostly as a result of drinking water fluoridation, the number of young patients affected by fluorosis increased considerably. This study describes a minimally invasive technique, using in-office dental bleaching (35% hydrogen peroxide) and enamel microabrasion (silicon carbide and 12% hydrochloric acid)to eliminate fluorosis like stains. The association of techniques was efficient and can be recommended as a good conservative alternative for the treatment of fluorosis affected teeth.

The aim of this work was to evaluate the concentration of carbamide peroxide compounded at different dispensing pharmacies. Immediate concentration analysis was made of bleaching gels dispensed by specialized pharmacies, and of a commercially available gel (control group) (n = 20). The carbamide peroxide concentration was determined by titration and the results were analyzed statistically by the Kruskal-Wallis test. The commercial bleaching agent (control group) and one of the gels from the pharmacies presented the best mean concentration values, close to 16%. In conclusion, the concentration of the manipulated and industrialized carbamide peroxide gels presented concentration values differing from 16%. Descriptors: Tooth bleaching; Peroxides; Pharmacies.Resumo: O objetivo deste trabalho foi avaliar a concentração do peróxido de carbamida manipulado em diferentes farmácias de manipulação. Foram utilizados géis clareadores manipulados em farmácias especializadas e um industrializado (grupo controle) (n = 20) com análise de concentração imediata. A concentração do peróxido de carbamida foi obtida por titulometria e os resultados foram submetidos a análise estatística pelo teste de Kruskal-Wallis. Como resultado, o agente clareador (controle) e um dos produtos manipulados em farmácia apresentaram as melhores médias de concentração, próximas a 16%. Pode-se concluir que a concentração do peróxido de carbamida manipulado e dos industrializados apresentaram valores de concentração diferentes de 16%.

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AIM: The objective of this study was to report a clinical case highlighting the main recommendations of the literature to minimize forces applied on implants. MATERIAL AND METHODS: A decision was made to increase the number and size of implants installed. Screwed and cemented prostheses were used, combined with an occlusal bruxism night guard. RESULTS: Four months after the prosthesis installation, no biological or biomechanical complications were encountered. CONCLUSION: There are cases of patients with parafunctional habit who require oral rehabilitation with implants. There are guidelines that enable planning and rehabilitation. It is important to monitor cases to assess the behavior of implants and their suprastructures.