1996 Fiscal Year Final Research Report Summary
Elucidation of mechanism of stimulating to hard tissue fomation ability by laser iradiation in dental pulp and its application
| Project/Area Number |
07457462
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Conservative dentistry
|
|---|
| Research Institution | Nihon University |
|---|
Principal Investigator |
YAMAZAKI Muneyoshi Nihon Univ., Dentistry at Matsudo, Professor, 松戸歯学部, 教授 (30050032)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
ABIKO Yoshimitsu Nihon Univ., Dentistry at Matsudo, Professor, 松戸歯学部, 教授 (70050086)
MATSUSHIMA Kiyoshi Nihon Univ., Dentistry at Matsudo, Assistant Professor, 松戸歯学部, 講師 (00157306)
|
|---|
| Project Period (FY) |
1995 – 1996
|
| Keywords | dental pulp / laser irradiation / alkaline phosphatase / osteocalcin / bone nodule / calcification |
|---|
| Research Abstract |
We examined the effect of low power laser irradiation on ability of hard tissue formation and metabolism of extracellular matrix involved calcification, using cultured human dental pulp cells (HDP cells). In this study, HDP cells were obtained from the third molars which were extracted form young patients in the course of orthodontic treatment. A Ga-Al-As diode laser (Matsushita, Inc., Tokyo, Japan, model : Panalas-1000), which has a continuous wavelength of 830 nm and maximal power output of 600 mw, was used. The total energy, corresponding to 10 min exposure, was 3.65 J/cm2.
The HDP cells were irradiated, just before the cells were confluent, for 5 or 10 min only once. The bone nodule of both cells irradiated and non-irradiated was found at 5 weeks ago after irradiation. The number of bone nodule formation of cells irradiated for 5 and 10 min were significantly increased compared with non-irradiated. The activity of alkaline phosphatase (ALP) was decreased and the production of osteocalcin was increased
We examined the effect of low power laser irradiation on metabolism of extracellular matrix. The effects of peptidoglycan extracted from Lactobacillus casei on the production of IL-6 in HDP cells were examined. The peptidoglycan stimulated IL-6 production in a time- and dose-depend manner. IL-6 treatment induced significantly high plasminogen activator activity in the HDP cells in a time- and dose-dependent manner compared with non-treated control. The production of IL-6 from HDP cells treated with LPS and irradiated were decreased compared with HDP cells treated with LPS and non-irradiated. Our findings were suggested that the destruct of extracellular matrix were inhibited and ability of hard tissue formation was enhanced by laser irradiation.
|
