Influence of light curing tip distance on microhardness, water sorption, solubility and color stability of a microhybrid resin composite / Influência da distância de fotoativação na microdureza, sorção, solubilidade e estabilidade de cor de uma resina composta microhíbrida

AUTOR(ES)

Nádia da Rocha Svizero D Alpino

DATA DE PUBLICAÇÃO

2009

RESUMO

The purpose of this in vitro study was to evaluate the influence of light curing tip distance on microhardness, sorption, solubility and color stability of a microhybrid resin composite (Filtek Z250-3M ESPE). Specimen discs (6mm x 2,5mm) were irradiated for 20s with a continuous output at 640mW/cm2, according to different curing tip distances: G1-0mm (control), G2-5mm, G3-10mm and G4-15mm. Specimens were stored dry in a lightproof container for 24h. Knoop hardness measurements were obtained on the top and bottom surfaces of the samples (100g, 15s) after 24h, 6 and 12 months. To evaluate sorption and solubility, specimens were desiccated to be weighed and then stored in distilled water until a constant mass was obtained. The reconditioning in the desiccators was also done until a constant mass. To evaluate de color stability of the resin composite, the first color measurements were made and then specimens were immersed in a grape juice twice a day for 10 minutes, during 28 days. Control groups were immersed in distilled water for the same period of time. Color measurements were made weekly using a spectrophotometer. Data from microhardness/ color stability and from water sorption/ solubility were submitted to three-way ANOVA/Tukey and one-way ANOVA /Tukey tests, respectively (p<0,05). For top and bottom surfaces, there were statistical differences among the curing tip distances after 24h. Although, the microhardness values were lower for both surfaces after 6 and 12 months. G3 and G4 showed significant higher water sorption and G4 higher solubility when compared to G1. Grape juice showed significant color change of the resin composite as a function of time and curing tip distance (G4). It may be concluded that the distance between light curing tip and resin composite surface decreases microhardness and color stability, and increases sorption and solubility of the evaluated resin composite.

ASSUNTO(S)

absorption dureza resinas compostas cor polimerização hardness solubility composite resins solubilidade absorção color polimerization

Documentos Relacionados

• Resistência à flexão, sorção, solubilidade e estabilidade de cor de compósitos odontológicos reforçados por fibras
• Sorção, solubilidade e resistência flexural biaxial de uma resina composta em função do tipo de fonte de luz e técnicas de polimerização
• Sorção, solubilidade e resistência flexural biaxial de uma resina composta em função do tipo de fonte de luz e técnicas de polimerização
• Influência das dimensões e do modo de fotoativação do corpo de prova sobre os testes de sorção, de solubilidade e de microdureza Knoop
• Kinetic of water diffusion and color stability of a resin composite as a function of the curing tip distance