Análise comparativa da profundidade de cura de uma resina micro-híbrida fotoativada por distintas fontes de luz

Resumo (EN)

Objective – This study used depth of cure measurement to compare the effectiveness of two light-emitting diodes units (Ultra Blue IS-DMC and Bright Lec- MMOptics) and a conventional quartz tungsten halogen equipment (Degulux – Soft-Star – Degussa). The microhardness of a light-cured resin composite (Z-250 -3M ESPE) was compared according to the depth from the composite surface. Methods – Seventy-five samples were made in polytetrafluoroethylene molds using a micro hybrid composite resin (Z250, 3M ESPE, St. Paul, MN, USA). Three different groups of: 1 mm, 2 mm and 4 mm resin layer thickness were determined. The microhardness of the upper and lower surfaces were measured with a Vickers hardness-measuring instrument and analyzed by a two-way ANOVA/Tukey's test (alpha = .05). Results – There were no statistically significant differences in the microhardness values among groups of 1mm layer thickness. When 2 mm of resin was used, significant differences were found based on curing light. The Ultra Blue IS-DMC and quartz tungsten halogen units showed better results when compared to Bright Lec-MM Optics. The conventional quartz tungsten halogen had overall the highest values of microhardness when 4 mm resin layer thickness of resin was considered. Conclusions – In this study, depth of cure differed significantly among the different light-curing units.