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

Abstract

Aim: 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. Materials and methods: 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. Results: 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. Conclusion: Application of a double layer of DBA resulted in a significantly lower intrapulpal temperature.