Abstract:

Objective　To study the best parameter of impulse Nd:YAG Laser-aided debracket.Methods　To measure the bonding strength of ceramic bracket and pulp cavity temperature after different laser energy. First group was not irradiated by la- ser, second groupwas irradiated by laser of power5W and irradiating duration 2s, third groupwas power3W and duration 3s, and fourthgroup was power 2W and duration 5s.Results　There were significant differences of bonding strength among the four groups. The bonding strength of ceramic bracketwas significantly reduced by laser irradiating. Therewere significant differences of the pulp cavity temperature increasing among different laser power irradiating groups. The lowest temperature increasing(3.65℃) groupwas the group of laser power 3W and irradiating duration 3s.Conclusion　The bonding strength of ceramic bracketswas sta- tistically reduced after laser irradiation and the best parameter of impulse Nd:YAGLaser-aided debracket is laser power3W and ir- radiating duration 3s.

Key words: laser, ceramic bracket, debracket, bonding strength