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 lowerthan the corresponding critical values 5.5°C.