Temperature analysis during bonding of brackets using LED or halogen light base units.

Area of Science:

• Dental Materials Science
• Biomedical Engineering
• Conservative Dentistry

Background:

• Photo-curable composite resins are widely used for bracket fixation in orthodontics.
• Various light sources, including halogen lamps and blue LED systems, are employed for composite polymerization.
• Monitoring intrapulpal temperature changes during light irradiation is crucial to prevent pulpal damage.

Purpose of the Study:

• To compare intrapulpal temperature variations induced by blue LED systems versus halogen lamps during composite resin photo-polymerization on permanent teeth enamel.
• To evaluate the clinical implications of these temperature changes for bracket bonding procedures.

Main Methods:

• Nine human extracted permanent teeth were used, including incisors and canines.
• Teeth were subjected to irradiation from a blue LED system and a halogen lamp at enamel surfaces (buccal and lingual) for 20, 40, and 60 seconds at a 45-degree angle.
• Intrapulpal temperature was measured using a thermistor placed in the pulpal chamber, with readings taken every second.

Main Results:

• A direct correlation was observed between irradiation time and the increase in intrapulpal temperature for both light sources.
• Halogen lamps induced significantly higher intrapulpal heating compared to the blue LED system.
• The blue LED system exhibited a shorter cooling period post-irradiation and minimal heat generation during use.

Conclusions:

• Blue LED systems are a preferable light source for photo-curing composite resins in bracket bonding due to lower heat generation.
• The reduced heating associated with blue LED technology may allow for shorter clinical operation times and improved procedural efficiency.
• Blue LED systems offer a potentially safer alternative for preventing pulpal stress during orthodontic bracket adhesion.