Influence of light intensity from different curing units upon composite temperature rise

Area of Science:

• Dental Materials Science
• Biomaterials Engineering
• Photopolymerization Technology

Background:

• Photopolymerization of composite resins inevitably increases tooth tissue temperature.
• Factors influencing temperature rise include illumination time, light intensity, proximity, composite properties, and thickness.
• Halogen curing units, widely used, emit broad spectra, with some wavelengths causing unnecessary heat without aiding polymerization.

Purpose of the Study:

• To evaluate the impact of curing unit light intensity on temperature elevation within a composite resin sample.
• To compare temperature rise generated by halogen and light-emitting diode (LED) curing technologies.

Main Methods:

• Utilized three curing units: Elipar Trilight (halogen), Astralis 7 (halogen), and Lux-o-Max (LED).
• Measured temperature increase in a Tetric Ceram composite resin sample using a Metex M-3850 D multimeter.
• Placed the temperature probe 1 mm deep into the unpolymerized composite resin, illuminating for 40 seconds.

Main Results:

• The Elipar Trilight halogen unit, in standard mode, induced the highest temperature rise (13.3 ± 1.21°C).
• The Lux-o-Max LED unit demonstrated the lowest temperature increase (5.2 ± 1.92°C).
• Significant differences in temperature elevation were observed between the tested halogen and LED curing units.

Conclusions:

• Light-emitting diode (LED) curing units generate less heat during composite resin polymerization compared to halogen units.
• Selecting appropriate curing technology, such as LED, can help mitigate excessive temperature rise in tooth tissue.
• Minimizing thermal stress during dental procedures is crucial for patient comfort and preventing adverse pulpal effects.