Influência da pressão pulpar simulada na variação de temperatura intrapulpar durante a fotopolimerização do sistema adesivo

Objective: To evaluate the effects of simulated pulpal pressure (SPP) on the variation of intrapulpal temperature (⃞T) during lightcuring of the adhesive system. Material and Methods: One hundred sound human molars were sectioned from the highest pulp horn to obtain a 2-mm of thickness dentin. The specimens were randomly divided into two groups: (n = 50), according to the presence or absence of SPP (15 cm H2O). The specimens were sequentially treated as follows: 37% phosphoric acid (Scotchbond Universal; 3M/ESPE), adhesive system (Scotchbond Universal/3M ESPE) and light-curing (10 s). ⃞T was evaluated during adhesive lightcuring with a K-type thermometer put inside the pulp chamber. Data were analysed by using Mann-Whitney’s test (at 5%). Results: According to Mann-Whitney’s test, the absence group presented a ⃞T of 2 °C, whereas the presence group 1 °C. The mean values of ⃞T were 0.82 ± 0.56 °C for the presence group and 2.30±0.73 °C for the absence group. Conclusion: Simulated pulpal pressure significantly reduced the temperature rise in the pulp chamber during light-curing of the adhesive system, showing the importance of inserting this protocol of simulated pulpal pressure in the laboratory procedures.