2004 Fiscal Year Final Research Report Summary
Study of biological effects of laser irradiation on cell factions and differentiation.
| Project/Area Number |
14207083
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (A)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Conservative dentistry
|
|---|
| Research Institution | Meikai University |
|---|
Principal Investigator |
KATAYAMA Tadashi Meikai Unversity, School of Dentistry, Professor, 歯学部, 教授 (10105596)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
YOKOSE Satoshi Meikai University, School of Dentistry, Associate Professor, 歯学部, 助教授 (90245803)
KATHO Yoshroh The Nippon Dental University, School of Dentistry at Niigata, Professor, 新潟歯学部, 教授 (20060452)
INOUE Hroshi Fukuoka Dental College, School of Dentistry, professor, 歯学部, 教授 (50067047)
HORIBA Naoki Aichi Gakuin University, School of Dentistry, Assistant Professor, 歯学部, 講師 (33902602)
GOMI Kazuhiro Tsurumi University, School of Dentistry, Associate Professor, 歯学部, 助教授 (10178460)
|
|---|
| Project Period (FY) |
2002 – 2004
|
| Keywords | Laser / in vivo / in vitro / Osteoblast / Fibroblast / Biological effect / Regeneration |
|---|
| Research Abstract |
Low Level Laser Therapy (LLLT) using CO_2 lasers is known to activate surrounding cells and tissue. However, few studies concerning LLLT using hard lasers have been performed, and much about the biological mechanisms of LLLT remains uncertain. In the present study, we report the morphological changes in rat tibiae irradiated by a CO_2 laser without surgical treatment. The purpose of this study was to histologically evaluate the effects of LLLT using a CO_2 laser on bone formation in rat tibiae. The left tibia underwent CO_2 laser irradiation, while the right tibia did not undergo CO_2 laser irradiation (Control). Rat tibiae were irradiated by CO_2 laser from the outside of the body. Irradiation was performed at the following power and exposure settings : power, 1.0 W ; duration : 15 min ; calculated energy density, 〜1. 1 kJ/cm^3. On the 7th day after irradiation, tibiae were removed and were analyzed by Soft X-ray. Serial sections were prepared for osteoid staining (Yoshiki's method) and ALP (Alkaline phosphatase) staining, and were examined for mineralized apposition rate (Calcein labeling). Soft X-ray examination revealed no differences between the control and CO_2 laser-irradiated groups. However, marked osteoid formation (Yoshiki's method) on the surface of laser-irradiated tibiae and young ALP-positive osteoblasts were present in the osteoid tissue. Interestingly, calcein labeling demonstrated that mineral apposition rate on the periosteum of laser-irradiated cortical bone was much higher than that in control tibiae. These results demonstrate that LLLT using CO_2 laser induced not only mineralization but also osteoblast differentiation. The present study suggests that lasers can be applied to bone regeneration treatment.
|
Research Products
(12 results)
