Pulp Chamber Temperature Rise during Resin Composite Polymerization

Objectives: To compare the pulp chamber temperature during illumination of resin-based composites using different light-curing units, and to assess the effects of a glass-ionomer (GI) base on the increase of pulp chamber temperature during polymerization. Material and Method: Standard occlusal cavities were prepared and restored with the adhesive bonding agent Clearfil Liner Bond 2V and the composite resin Clearfil AP-X. The GI base, Aqua Ionobond, was preapplied. Groups were polymerized with a halogen-curing lamp (QTH) and with a LED lamp. Intrapulpal temperature rises were measured at 60sec intervals and data analyzed using ANOVA, Post-Hoc Scheffé and t-test. Results: The smallest rise was recorded when a GI base was applied to the cavity floor and the halogen curing lamp used, while the highest rise occurred when the LED curing lamp used directly over the bonding agent. Conclusion: Visible light-cure lamps varied greatly in the amount of heat emitted and judicious choice of lamps can minimize the potential for pulpal damage. The GI liner lowered the pulp chamber temperature rise occurring during the illumination of composite restoration significantly.