Temperature increases in primary teeth pulp chamber during polymerization of glass ionomer-based restorative materials

PURPOSE: To evaluate the temperature changes in primary teeth pulp chambers of different dentin thicknesses during polymerization of four glass ionomer-based restorative materials. MATERIALS AND METHODS: Eighty extracted, caries‑free, primary molars were prepared as standardized Class I occlusal cavities with dentin thicknesses of 1 mm and 2 mm. Four glass ionomerbased restorative materials, Dyract XP, Photac Fil Quick Aplicap, Fuji II LC, and GCP Glass Fill, were placed in the cavities and cured with two light-curing units. Temperature increases (initial temperature, 37°C) in the pulp chamber during polymerization were recorded by a J-type thermocouple in a pulpal microcirculation set-up. The data were analyzed with Variance analyses and Tukey tests. RESULTS: The temperatures recorded in samples with dentin thicknesses of 1 mm and 2 mm exhibited statistically significant differences (p<0.05). The GCP Glass Fill group exhibited the highest temperature increases for both dentin thicknesses (p<0.05). The other groups were not statistically different but the Dyract XP group exhibited the least temperature change. CONCLUSION: The highest temperature changes were observed for 1 mm dentin thickness. All temperature increases during polymerizations and setting reactions were lower than the corresponding critical values 5.5°C.