Comparative evaluation of aluminum foil and air/water spray as temperature control method using direct provisionalization

Purpose: Temperature control is essential during the direct fabrication of provisional crowns in Fixed partial denture. Aim: To compare the effectiveness of aluminum foil and air/water spray as a temperature control method during direct fabrication of provisional crown using two different provisional resin materials. Material and Method: The apical portion of a freshly extracted and treated mandibular first molar was resected following which pulp tissue was removed. The tooth was embedded in acrylic resin and prepared with 1.5mm shoulder finish line. The thermal probe connected to digital thermometer was inserted into the pulp chamber and amalgam was condensed around it. In vitro measurements were made of heat transferred to pulp chamber during fabrication of provisional restoration with polymethylmethacrylate (PMMA) and Bis acrylic composite resin. The provisional materials to be tested were divided into subgroups based on cooling technique used: (1) Control-no coolant used; (2) Aluminum foil group-provisional restoration was fabricated after application of the foil on the prepared tooth; (3) Air/water spray – the provisional restoration was left in place and cooled with air/water spray after initial polymerization. The temperature was recorded during polymerization at 30s interval until it was evident that the peak temperature has been reached. Data was analyzed with descriptive statistics, ANOVA and Tukey Honestly Significant Differences tests (p < 0.5). Results: PMMA produced higher exothermic reaction than Bis acrylic composite resin. The temperature rise was significantly reduced with use of aluminum foil and air/water spray in PMMA group. Conclusions. Air water spray and aluminum foil can be effectively used as temperature control method with polymethylmethacrylate resin.