Composite conversion and temperature rise using a conventional, plasma arc, and an experimental blue LED curing unit

Area of Science:

• Dental Materials Science
• Polymer Chemistry
• Biomedical Engineering

Background:

• Photopolymerization is crucial for dental composite restoration.
• Traditional light sources and newer plasma technologies have limitations.
• Investigating novel light sources like blue LEDs is essential for optimizing dental curing.

Purpose of the Study:

• To evaluate the degree of conversion and temperature rise in composite materials using blue superbright light emitting diodes (LEDs).
• To compare the performance of blue LEDs against plasma light and a traditional photopolymerization unit.
• To analyze the relationship between light intensity, spectral distribution, and photopolymerization efficiency.

Main Methods:

• Utilized Fourier transform infrared (FTIR) spectroscopy to measure the degree of conversion.
• Employed a digital multimeter to record temperature rise during polymerization.
• Compared three composite materials under experimental blue LEDs, plasma light, and a conventional unit.

Main Results:

• Conventional curing resulted in significantly higher degree of conversion values.
• Blue LEDs and plasma light generated significantly lower temperature rises compared to the conventional unit.
• Blue LEDs operated at a much lower intensity (9 mW cm-2) than plasma light (1370 mW cm-2) and the conventional unit (560 mW cm-2).

Conclusions:

• Blue LEDs offer a promising alternative for dental composite photopolymerization due to lower heat generation.
• The spectral match between blue LEDs and camphorquinone (CQ) likely explains their efficiency at lower intensities.
• Further research is warranted to optimize blue LED technology for clinical dental applications.