Effect of Dentin Bonding Agent on Intrapulpal Temperature during Fabrication of Provisional Restorations by a Direct Method: An In Vitro Study

Abstract

To determine the effect of three different provisional restorative materials (PRMs) and application of dentin bonding agent (DBA) on intrapulpal temperature rise during fabrication of provisional crowns using a direct method. Three PRMs-polymethyl methacrylate resin (PMMA), bis-acrylic resin, and dimethyl methacrylate resin (DMMA)-were used in the study. Dentin bonding agent (Single Bond 2, 3M ESPE, Germany) was applied in a single layer or double layer as an insulating material. A total of 45 molars were prepared for complete coverage restoration with chamfer finish line and 1.5 mm axial and 2 mm occlusal reduction. After application of a single or double layer of DBA, provisional materials were polymerized according to the manufacturer's instructions. The temperature increase inside the pulp chamber was measured with a T-type thermocouple wire. The readings were averaged for each group to determine the mean value of temperature rise. Statistical analysis was performed with analysis of variance (ANOVA) followed by post hoc Tukey test (a = 0.05). The temperature rise varied according to the provisional restoration material used (PMMA > DMMA > bis-acrylic resin) (p < 0.001) and the single or double layer of DBA (p < 0.001). Polymethyl methacrylate resin produced a higher intrapulpal temperature. Application of a double layer of DBA resulted in a significantly lower intrapulpal temperature.