Effects of Low-Level Laser Therapy After Corticision on Tooth Movement and Paradental Remodeling

Background and Objective: Both Corticision and low-level laser therapy (LLLT) are known to affect the rate of tooth movement. Our objective was to investigate the combined effects of Corticision and LLLT on the tooth movement rate and paradental remodeling in beagles. Study Design/Materials and Methods: The maxillary second premolars (n = 24) of 12 beagles were randomly divided into four groups (n = 6 per group) based on the treatment modality: group A, only orthodontic force (control); group B, orthodontic force plus Corticision; group C, orthodontic force plus LLLT; group D, orthodontic force plus Corticision and LLLT. Results: Ratios of second premolar-to-canine movement were greater by 2.23-fold in group B and 2.08-fold in group C, but 0.52-fold lesser in group D than in group A. The peak velocity was observed at an earlier stage of tooth movement in group B but at a later stage in group C during the 8-week treatment period. At week 8, both tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts on the compression side and proliferating cell nuclear antigen (PCNA)positive osteoblasts on the tension side increased significantly (P<.05) in group C but decreased in group D. Histomorphometric analysis revealed that the mean apposition length of newly formed mineralized bone during the 8 weeks of treatment significantly increased in both group B (2.8-fold) and group C (2.2-fold). In group D, the labeling lines on lamina dura were thin and discontinuous, but intratrabecular remodeling and lamellation were found to be active. Conclusion: Periodic LLLT after Corticision around a moving tooth decreased the tooth movement rate and alveolar remodeling activity. Lasers Surg. Med. 41:524533, 2009. (C) 2009 Wiley-Liss, Inc.