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The effects of chemical polishing on dental acrylic resin properties are not well clarified. This study evaluated the effect of chemical and mechanical polishing on the residual monomer release (RM), Knoop hardness (KH), transverse strength (TS) and surface texture (ST) of a heat- and self-cured acrylic resin. Four groups were formed: GI-self-cured resin/mechanical polishing; GII-self-cured resin/chemical polishing; GIII-heat-cured resin/mechanical polishing; GIV-heat-cured resin/chemical polishing. Following the polishing procedures, specimens were stored in distilled water at 37 degrees C. The KH and RM measurements were taken after 1, 2, 8 and 32 days of storage, and TS after 2, 8 and 32 days. Surface texture was observed under SEM evaluation. Results were compared statistically at a confidence level of 95%. The following conclusions were drawn: (1) regardless of the acrylic resin and the period of analysis, chemical polishing increased RM levels, reduced KH, and did not affect TS significantly; (2) water storage increased the surface hardness of GII and GIV; (3) GII and GIV showed a smooth and wavy surface under SEM evaluation.

O objetivo deste trabalho foi analisar as percepções de um grupo de idosos sobre a perda de dentes. Realizou-se uma pesquisa qualitativa que utilizou O Discurso do Sujeito Coletivo como técnica metodológica para a ordenação dos dados. A análise das entrevistas e a construção do Discurso do Sujeito Coletivo revelaram informações sobre os pensamentos e valores associados à perda de dentes no grupo. Os principais resultados sugerem que a falta de dentes trouxe problemas funcionais e psicológicos, mas que parecem ser compensados pela resolução do problema estético. As justificativas reveladas pelo sujeito coletivo para o edentulismo refletem predominantemente o modelo de atenção à saúde, em que predominam procedimentos cirúrgico-restauradores e reabilitadores, em detrimento de ações preventivas e educativas. Desta forma, torna-se imprescindível o desenvolvimento de iniciativas no campo da educação e prevenção em saúde bucal, enfatizando ações voltadas para a atenção integral do idoso, destacando-se a dimensão social das doenças e o papel do Estado como provedor da saúde e da qualidade de vida de todos os cidadãos.

Objective:The presence of Candida albicans on the surfaces of denture-base acrylic resins is strongly related to the development of oral stomatitis. This study evaluated the antifungal action of different agents over microwave-cured acrylic resin without polishing specimens previously contaminated with Candida albicans.Material and Methods:Sixty specimens were immersed in BHI broth previously inoculated with the yeast and stored for 3 h at 37°C. They were divided into 5 experimental groups (n=10): G1: 2% chlorhexidine solution (10 min); G2: 0.5% sodium hypochlorite (10 min); G3: modified sodium hypochlorite (10 min); G4: effervescent agent (5 min); G5: hydrogen peroxide 10v (30 min). The specimens of the control group 1 (C1) were not disinfected. Ten additional specimens of the control group 2 (C2) were not infected with the yeast, aiming to check the asepsis during the experiment. The disinfection agents were neutralized and the acrylic resin specimens were immersed in BHI Broth for 24 h. Culture media turbidity was evaluated spectrophotometrically according to the transmittance degree, i.e. the higher the transmittance the stronger the antimicrobial action. Statistical analysis was performed (Kruskal-Wallis Test, p<0.05).Results:The results, represented by the medians, were: G1 = 40; G2 = 100; G3 = 100; G4 = 90; G5 = 100; C1 = 40; C2 = 100.Conclusions:This in vitro study suggested that sodium hypochlorite-based substances and hydrogen peroxide are more efficient disinfectants against C. albicans than 2% chlorhexidine solution and the effervescent agent.

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