Heat generated by grinding during removal of ceramic brackets

Area of Science:

• Dental Materials Science
• Orthodontic Technology
• Pulp Biology

Background:

• Ceramic bracket fracture necessitates fragment removal, often by grinding.
• Grinding ceramic surfaces can generate excessive heat, potentially damaging the dental pulp.
• Understanding intrapulpal temperature changes during this process is crucial for patient safety.

Purpose of the Study:

• To measure intrapulpal temperatures during ceramic bracket fragment removal.
• To compare these temperatures with known thresholds for pulpal pathosis.
• To evaluate the effectiveness of coolant use in mitigating heat generation.

Main Methods:

• Intrapulpal temperature measurements using a thermocouple probe on extracted teeth.
• Grinding of 122 ceramic brackets (three brands) with high-speed diamond burs and low-speed green stones.
• Testing with and without air or water coolant.

Main Results:

• Low-speed grinding without coolant significantly increased pulp chamber temperature (p < 0.001) for all bracket types.
• High-speed grinding, regardless of coolant, did not elevate pulp chamber temperature.
• Low-speed grinding with air or water coolant also prevented significant temperature increases.

Conclusions:

• Low-speed grinding of ceramic brackets without coolant poses a risk to dental pulp vitality.
• The use of air or water coolant during high-speed or low-speed grinding effectively prevents detrimental temperature rises.
• Employing coolant during ceramic bracket removal is essential to protect the dental pulp.