Effects of low level laser on orthodontic tooth movementmodel in rats

• Main Authors: Yang-cheng Chen, 陳泱錚
• Other Authors: Chung-Chen Yao
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/cxcu3j

碩士 === 國立臺灣大學 === 臨床牙醫學研究所 === 105 === Orthodontic tooth movement (OTM) is the result of periodontium remodeling after mechanical force application. The remodeling includes many cytokines involved. RANKL-RANK-OPG system is one of the important keys to achieve periodontium remodeling, and different approaches were attempted to accelerate tooth movement. Lots of literatures support that low level laser therapy (LLLT) can increase rate of orthodontic tooth movement. The possible mechanisms are activating osteoclasts activity through the RANKL-RANK pathway, stimulating bone formation, and early removal of hyalinization tissue. There are many factors contributing to the RANKL-RANK system. The aim of present study is to explore the LLLT effects on the bone remodeling of OTM in rat model. IVIS living image system was used for detecting luciferase actvitiy under MMP3 promoter at early stages of OTM, and immunohistochemistry was used to analyze the expression RANKL、OPG、VEGF、PECAM-1、HIF-1α、PCNA、MCP-1 at the tissue levels at day 1, day 3, day 7, day day 21 after OTM. The results reveal that MMP3 may be not an appropriate reporter of LLLT acceleration, however, the expression of RANKL、VEGF、HIF-1α及MCP-1 are upgraded early after LLLT stimulation. The number of osteoclasts are significantly higher in the high dose irritation group. And LLLT but without OTM, enhances HIF-1αexpression during physiological molar distal drifting in rats. We suggest that the effects of LLLT on accelerating orthodontic tooth movement are related to RANKL-RANK system and possibly the HIF-VEGF pathway.