In Vitro Evaluation of the Effect of Light-Cured Pulp-Capping Materials on Intrapulpal Temperature and Recovery Time During Sequential Light-Curing.

OBJECTIVE

Thermal insult is one of the factors contributing to pulpal damage during dental procedures, particularly in deep cavities with minimal dentine thickness. This study aimed to evaluate the effect of different light-cured pulp-capping materials on intrapulpal temperature (IPT) changes and thermal recovery time during sequential light curing in deep cavities.

METHODS

Deep Class 1 cavities were prepared for 56 extracted premolars, maintaining a dentine thickness of 0.5 mm. Teeth were divided into 4 groups (n=14) based on the pulp-capping materials: TheraCal LC, Biner LC, izy INO LC and Urbical LC. A digital thermometer was used to measure IPT by inserting a connected K-type thermocouple through the apices to reach the pulp chamber of the teeth that were suspended in a water bath at 37°C. Intrapulpal temperature measurements were recorded during the sequential restorative procedure starting from: baseline T0 (35°C), T1 after curing of each pulp-capping material, T2 after curing of the adhesive agent, T3 after curing the first 2-mm resin composite layer and T4 after curing the final resin composite layer. Intrapulpal temperature changes (ΔT) after each light-curing step were calculated relative to the baseline temperature. Recovery time after completion of the restorative procedure was recorded using an infrared camera. The data were analysed using 1-way ANOVA and post hoc tests at P < .05.

RESULTS

The highest IPT change was recorded at ΔT4 for izy INO LC (8.59°C), followed by Biner LC (8.55°C), TheraCal LC (7.11°C) and Urbical LC (6.85°C). A significant difference in IPT value was observed only at ΔT4 (P <.05), with Urbical LC showing significantly lower values than both izy INO LC (P=.046) and Biner LC (P=.049). The fastest recovery times were recorded for TheraCal LC (2.22 minutes) and Biner LC (2.58 minutes), which were significantly shorter than Urbical LC (4.25 minutes) (P < .05).

CONCLUSION

None of the tested pulp-capping materials was able to maintain the IPT increase below the critical threshold during the sequential light-curing procedure. Urbical LC showed lower temperature rise but slower thermal recovery than the other materials.