A Comparative Evaluation of Temperature Changes in the Pulpal Chamber during Direct Fabrication of Provisional Restorations: An In Vitro Study.

To compare the temperature changes in the pulpal chamber during fabrication of provisional restorations by direct method. A total of 108 three-unit FPD provisional restorations were fabricated on a study model and divided into three main groups according to the material used for the fabrication of matrix. Group A-Alginate impression index group, Group B-Polyvinylsiloxane putty impression index group, Group C-Vacuum formed template group. Each group comprising of 36 specimens, was subdivided into three subgroups based on the provisional restorative material used: polymethylmethacrylate (subgroup 1), polyethylmethacrylate (subgroup 2), bis-acryl composite resin (subgroup 3). Intrapulpal temperature changes were observed with the help of a thermocouple probe (connected to a digital microprocessor thermometer) inserted into the pulp chamber of an extracted mandibular second molar mounted on a study model, during the fabrication of provisional restorations by direct method. The subgroups mean temperature rise observed in Group A-A1, A2, A3 was 2.6250 ± 0.2491, 1.0500 ± 0.1382, 0.4083 ± 0.1165, respectively. The subgroups mean temperature rise observed in Group B-B1, B2, B3 was 4.6250 ± 0.2454, 3.3750 ± 0.3415, 2.5917 ± 0.2678, respectively. The subgroups mean temperature rise observed in Group C-C1, C2, C3 was 4.7694 ± 1.8361, 3.0611 ± 1.5767, 2.3806 ± 1.5713, respectively. The observations were statistically significant. The intrapulpal temperature rise during fabrication of a provisional restoration depended both on the type of provisional restorative material and the type of matrix used. The clinician should choose carefully the resin and the matrix material while fabricating provisional restorations with direct method.