Budget Amount *help |
¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000)
Fiscal Year 2010: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000)
Fiscal Year 2009: ¥2,600,000 (Direct Cost: ¥2,000,000、Indirect Cost: ¥600,000)
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Research Abstract |
This study deals with temperature measurement of enamel surface of the human tooth during cavity preparation by the irradiation of Er : YAG laser beam. Surface temperature is measured using a three-color pyrometer and the influence of laser condition is investigated. Additionally, the dynamic stress induced in extracted human enamel by irradiation with Nd : YAG laser beam is measured. Moreover, the bactericidal effects of Nd : YAG laser by using a reaction mediator of TiO_2 are described. As a result, the surface temperature during Er : YAG laser irradiation ranges from 220 to 410℃ depending on the laser energy density and it is considerably lower than the melting point of human enamel. The induced dynamic stress was related to the volume of prepared cavity. The sterilization of bacteria might be caused by the mechanical effects induced by a laser beam irradiation.
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