Evaluating temperature increase during the polymerization of dental acrylic resin materials used for the direct fabrication of anterior deprogramming devices.

Abstract Statement of problem The polymerization of acrylic resin materials used for the direct fabrication of anterior deprogramming devices results in a temperature increase because of the exothermic reaction. This heat release might cause thermal trauma to the pulp, compromising the tooth’s vitality. Purpose The purpose of this in vitro study was to compare the temperature increase and the timing of the maximum temperature recording obtained inside the pulp chamber of a maxillary central incisor during the polymerization of different resins materials used for the direct fabrication of anterior deprogramming devices. Material and methods The exothermic reaction was examined during the polymerization of 4 different polymethyl methacrylate resin products: Pattern Resin LS; GC America, DuraLay inlay pattern resin; Reliance Dental, Kallocryl CPGM red; Speiko, and mega-Model Resin NF; Megadental. A polymeric matrix was fabricated to simulate the anterior deprogramming device. A freshly extracted intact maxillary central incisor was fixed in an acrylic resin mold, and a thermal probe was inserted into the pulp chamber to transmit the temperature recordings. The resin materials were mixed as per the manufacturer’s instructions and an equal volume of each was inserted into the plastic matrix, which was then positioned on the tooth. The temperature increase and the time needed to obtain the maximum temperature were recorded. The temperature and time recordings were performed initially for the intact tooth and repeated after the tooth was prepared for a metal-ceramic restoration. The data were analyzed with descriptive statistics, 1-way analysis of variance, and the Tukey Honestly Significant Difference tests (α=.05). Results In accordance with the 1-way ANOVA, there was a statistically significant difference both in temperature increase (F [7,72] = 3.72, P=.002) and in the recorded time (F [7,72] = 160.80, P Conclusions The Pattern Resin LS revealed the lowest exothermic reaction (P