Thermal Conductivity of Different Composite Rezin Materials in Different Polymerization Times and Modes

Abstract

Objective:The current study investigated the thermal conductivity of dimethacrylate-and silorane-based composite resins at different polymerization times and modes. Materials and Method:Forty dentin discs (8 mm diameter, 1.5 mm thick) were obtained from caries-free human molar teeth. Filtek Silorane (3M ESPE, Minnesota, USA) and Filtek Z550 (3M ESPE, Minnesota, USA) composite were polymerized with a LED (Light-Emitting-Diode) curing device (Valo, Ultradent Products Inc., Utah, USA), in two modes in different times (xtra power mode, 3200 mW/cm 2 ; 3-, 6-, 9-, 12-, +2 s / standard mode 1000 mW/cm 2 , 10-, 20-, 30-, 40-, +2 s)(n=10). Temperature changes in the dentin discs were measured with a K-type thermocouple (E-680, Elimko Co., Ankara, Turkey) and recorded.Data were statistically analyzed using Analysis of variance and independent sample t test (α=0.05) Results: Mean temperature changes were significantly different among polymerization times and modes (p<0.05). Temperature change of Filtek Silorane were significantly higher thanFiltek Z550 for each time interval and curing mode (p<0.05). Conclusion:As the polymerization time increases, the temperature increase in the dentin may adversely affect to the pulp health.