Microdureza de resinas em função da cor e luz halógena

Abstract

The aim of this study was to evaluate the influence of light intensity and the influence of the color of a composite resin on Knoop hardness. Samples were confected utilizing polyester matrices with 6 mm of diameter and 2 mm of depth. The matrices were filled with composite resin (Fill Magic - Vigodent), colors A3, B3, C3, D3 and I, and light-cured by means of an Elipar light-curing unit in three different light intensities: 450 mW/cm2, 800 mW/cm2 and an increasing intensity setup of 100 mW/cm2 to 800 mW/cm2. Ninety test specimens were confected, with the standard curing time of 40 seconds. The specimens were stored at 37 +/- 1 degrees C and immersed in distillate water. The Knoop test was carried out in superficial and deep areas of the specimens. The results revealed that there was no statistical difference (Tukey) between the tested colors. However, there was statistical difference between different light intensities. The authors concluded that the color of the composite resin did not influence Knoop hardness and that the progressive intensity setup led to the best Knoop hardness.

Dentine bond strength of a composite resin polymerized with conventional light and argon laser

“…However, in a clinical situation, professionals should not use application parameters different from the ones recommended by the manufacturer, because this could cause damage to adjacent tissue 4 . Halogen light and the argon laser for 30 seconds demonstrated no statistical difference regarding the filling technique probably because of the greater exposure time for the laser and the greater energy density of the conventional light favoring greater power of light penetration and, consequently, a deeper curing capacity 12 .…”

Evaluation of Compressive Strength and Microhardness of Composites Associated to Light Curing Characterizing Materials

“…The LCCMs black and white have around 12 to 13% of inorganic fi ller in full weight, while composite resin Filtek Z350 XT opacities for enamel and translucent colors (groups E and T), which showed the better values for this study, have in their composition 78.5 and 72.5% of inorganic fi ller respectively. Additionally, other studies 24,25 observed that polymerization degree directly infl uence the hardness variation of Bis-GMA based composite resins. As LCCMs composition shows high quantities of pigments, the conversion degree from monomers to polymers could be reduced, compromising superficial microhardness of these materials.…”

"Estudo do efeito da distância da ponta de aparelhos fotoativadores na microdureza e no grau de conversão da resina composta usando luz halógena, laser de argônio e LED"

“…BRYANT, 1990;CALDAS et al, 2003;MANGA;CHARLTON;WAKEFIELD, 1995;CHUNG;GREENER, 1990;CONSANI et al, 2002;CORRER-SOBRINHO et al, 2000;VOUGIOUKLASKIS;CAPUTO, 1987;ERSOY et al, 2004;FERRACANE, 1985;FERRACANE;GREENER, 1986;HANSEN;ASMUSSEN, 1997;KANCA 3rd , 1985;KNOBLOCH et al, 2004;MANDARINO et al, 1992;MASUDA;MALUF;MUENCH, 1999;MARTINS et al, 2002;NAUFEL;NEVES et al, 2002;PERIS et al, 2005;PILO;CARDASH, 1992;PIRES et al, 1993;ANDREOU, 2004;RAMOS;GARONE NETTO;BURGER, 2003;RODE et al, 2001;RODE et al, 2005;RYGE;FOLEY;FAIRHURST, 1961;SANTOS, 2003;SAY et al, 2003;UMBEHAUN, 2001;COMBE, 1987 …”

“…, 1995;MARTINS et al, 2002;PERIS et al, 2005;PIRES et al, 1993;PRICE et al, 2002;SANTOS, 2003;SOH et al, 2004;ST-GEORGES et al, 2002;UNTERBRINK;MUESSNER, 1995;SCHIMIT, 1998;YAP et al, 2004).…”

“…Alguns trabalhos mostram haver influência da cor da resina composta na dureza do compósito (AGUIAR et al, 2005;ERSOY et al, 2004;FRIEDMAN;HASSAN, 1984;LELOUP et al, 2002;MANDARINO et al, 1992;RISSI;CABRAL, 2002), apesar de alguns afirmarem que a cor não foi fator determinante na dureza (MARTINS et al, 2002;CAUGHMAN;CURTIS JR, 1994). A cor da resina selecionada foi a A3, uma cor universal.…”