Temperature Change in the Pulp Chamber Induced by Different Light Curing Units In Simulated Deep Cavities

Objective: The objective of this study was to evaluate the effect of various types of photopolymerization devices on the temperature of the pulp chamber during the adhesive bonding phase. Materials and Methods: To this purpose, cavities with a mesiodistal diameter of 5 mm, a buccolingual diameter of 3.5 mm, and a residual dentin thickness of 1.2 mm at the cavity base were prepared. Polymerization lights were applied for 20 seconds using three different devices. The temperature change within the pulp chamber was quantified using a thermocouple, with data collected at 10 and 20 seconds utilized for assessment. The mean intra-pulp temperature in the O-Light, Deepcure-L, and Valo groups at the 10th second was 39.9°C, 41.1°C, and 38.7°C and at the 20th second, had temperatures of 42.4°C, 44.3°C, and 40.4°C, respectively. Result:A statistically significant difference was observed between the Deepcure-L and Valo groups (p < .01) in terms of maximum temperature, increase in pulp chamber temperature, and temperature at the 10th and 20th seconds. The observed changes in pulp chamber temperature between the groups, irrespective of light transmission type, are consistent with the power output of the devices, expressed in mW/cm². All the groups yielded a temperature increase above the limit which has been described critical. Conclusion: During adhesive bonding phase, lower mW/cm² devices could be preferred in cases where the remaining dentin thickness is reduced.