Thermal Effects of Rapid High-Intensity Light Curing on Bulk-Fill Resin-Based Composites: A Systematic Review and Meta-Analysis

Abstract

Objective: The objective of this study is to evaluate whether high-intensity, short-duration light curing of bulk-fill resin-based composite (RBC) causes an increase in temperature of the material, compared to the standard light-curing protocol. Methods: This review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement and registered in the Open Science Framework database (10.17605/OSF.IO/UNW7C). Electronic searches were carried out in the PubMed/MEDLINE, Embase, Web of Science, Scopus, and Virtual Health Library databases for articles published up to April 2025. In vitro studies comparing the increase in temperature during high-intensity light curing and the standard protocol for bulk-fill RBCs were considered eligible. Seven different parameters assessed the risk of bias, and the studies were subjected to two 2 meta-analyses (light curing of 3 and 10 s and 3 and 20 s), according to the increment thicknesses (1–4 mm in depth) of the bulk-fill RBCs. The quality of the evidence was assessed using the GRADE tool. Results: The search identified 607 studies. After applying the eligibility criteria, six studies were included in the review, with one study classified as having a moderate risk of bias and five studies classified as high risk. Four studies were included in two different meta-analyses, which presented moderate heterogeneity (I2 = 56%, 88%, and 66%, respectively). The first meta-analysis (comparing 3 and 10 s light-curing protocols) showed statistical significance (p = 0.008), while the second meta-analysis (comparing 3 and 20 s) did not demonstrate statistical significance (p = 0.20). The certainty of the evidence was rated as very low. Conclusion: The use of high-intensity, short-duration light-curing protocols is thermally applicable based on limited in vitro studies with very low certainty of evidence. However, in clinical situations involving deep cavities with reduced residual dentin thickness, the use of high-intensity curing should be avoided to minimize the risk of thermal damage.