Temperature variation caused by high-intensity LED curing lights in bovine dentin

Area of Science:

• Dental Materials Science
• Polymerization Technology
• Biomaterials

Background:

• Dental resin composites require effective polymerization using curing lights.
• Different curing light technologies, such as Light-Emitting Diodes (LED) and Quartz-Tungsten-Halogen (QTH), have varying energy outputs.
• Heat generation during polymerization can potentially affect dental tissues.

Purpose of the Study:

• To compare the temperature variations in bovine dentin induced by high-intensity LED and QTH curing appliances.
• To assess temperature changes at different stages of the dental restoration process.

Main Methods:

• Forty-five bovine dentin slices (0.7 mm thick) were divided into three experimental groups.
• Temperature variations were measured during adhesive polymerization (10s), resin composite polymerization (40s), and 24 hours post-polymerization.
• Statistical analysis included ANOVA repeated measures and Tukey's post-hoc tests.

Main Results:

• A statistically significant difference in temperature variation was observed (p = 0.0001).
• The SmartLite PS LED appliance induced a significantly higher temperature increase than other appliances after adhesive polymerization.
• Both LED appliances generated significantly greater temperature increases than the QTH light during resin composite polymerization and 24 hours post-polymerization.

Conclusions:

• High-intensity LED curing lights, particularly the SmartLite PS, lead to greater temperature increases in dentin compared to QTH lights.
• The thermal effects of LED curing persist beyond the immediate polymerization phase.
• Clinicians should consider the potential thermal impact of different curing light technologies on dental substrates.