Effect of Nd:YAG laser on bone formation in rat tibia defects: three-dimensional micro-computed tomography image
Munemitsu Kawano1, Kei Wada2, Yuichi Hemmi1
1Division of Endodontics and Operative Dentistry, Department of Restorative and Biomaterials Sciences, Meikai University School of Dentistry, 1-1 Keyakidai, Sakado, Saitama, 350-0283, Japan.
Abstract:
Nd:YAG laser is in common clinical use for the treatment of tissue incision, transpiration, and haemostasis in soft tissues. However, few studies have reported the effects of low-level laser therapy (LLLT) from Nd:YAG laser on bone healing. The aim of this study was to perform three-dimensional (3D) morphological evaluation of the photobiomodulation of Nd:YAG laser in bone defects in rat tibiae using micro-computed tomography CT (micro-CT) imaging. A bone defect was created in each tibia of 30 rats. The right side was treated with LLLT from Nd:YAG laser (LT group) daily until sacrifice and the left tibiae served as controls (control group). All tibiae underwent micro-CT imaging at 7, 14, and 21 days after the operation. Three-dimensional image analysis of bone volume (BV) and bone surface area (BS) of new bone formation in the defects was performed and histologic analysis was conducted for all tibiae. Tibial BV and BS values were highest in both groups at 7 days after the operation and decreased at 14 days after operation. BV and BS values were both significantly higher in the LT group than in the control group at 7 and 14 days. There was no significant difference between the groups for either metric at 21 days. The present findings demonstrate that Nd:YAG laser simulates bone formation during the early healing period.
