Recently, much attention has been given to various biological effects to the reaction from low power laser irradiation. Among these effects, it is widely admitted thatwound healing is advanced by low power laser irradiation. In the present study, the effectof low power diode laser irradiation on the growth process of teeth as examined using theorgan culture of tooth germs dissected from 17-day-old mouse embryos. The irradiation of30mW was applied to tooth germs for 1 to 7 days for 5 minutes per day and the effect on thetooth germ was evaluated by biochemical analysis and histological observation.
Irradiation for 1, 3, 5 or 7 days did not increase the alkaline phosphatase activity in the tooth germ. Irradiation for 5 or 7 days increased the calcium content in the tooth germ.
Histologically, irradiation for 5 days increased the quantity of enamel, irradiation for 7days increased the quantity of enamel and dentine. These results suggest that irradiation oflow power diode laser accelerate the mineralization of the tooth germ. For evaluating theaction on mineralization in the tooth germ, irradiation for 7 days was optimal. (J. Jpn. Soc. Laser Dent. 4: 39-43, 1993 Reprint requests to Dr. Isobe)
