2018 年 27 巻 3 号 p. 214-218
Background: laser aided debonding of ceramic brackets has been proved to be effective in reducing
enamel surface damages, though the optimal parameters of laser to be chose is in question. The aim of
this study was to investigate the six different regimens of diode laser irradiation on enamel surface characteristics
and intrapulpal temperature changes while debonding.
Material and Methods: 90 polycrystalline brackets were bonded to 90 intact extracted premolars. At
debonding, teeth were divided into 6 groups (n = 15) and were subjected to the following regimen of
diode laser irradiation; G1 = 2 W, continuous wave, G2 = 2.5 W, continuous wave, G3 = 3 W, continuous
wave, G4 = 2 W, pulsed mode, G5 = 2.5 W, pulsed mode, G6 = 3 W, pulsed mode. After debonding, the
adhesive remnant index, the lengths and frequency of enamel cracks were compared among the groups.
5 teeth out of 15 were randomly selected from each group to assess the intrapulpal temperature changes.
Results: The number of enamel cracks increased significantly in all the specimens after debonding.
Enamel crack length increased significantly in all the study groups except G3 and G6. The increase in
intrapulpal temperature was significantly below the benchmark of 5.5 C for all the specimens. Significant
difference was observed in adhesive remnant index scores among the groups and more than half of the
teeth showed a score of 2.
Conclusion: Diode-laser irradiation in pulsed mode or continuous wave at given outputs (2, 2.5, 3 W)
were not statistically different in regard to producing enamel surface damages or increasing intrapulpal
temperature.