Evaluation of effects of low-level laser therapy on orthodontic tooth movement by quantitative estimation of the Tartrate resistance acid phosphatase levels in gingival crevicular fluid

Abstract

To test the hypothesis that mechanical forces combined with low-level laser therapy stimulates the rate of orthodontic tooth movement; by clinically measuring the canine retraction and histologically evaluating the Tartrate Resistant Acid Phosphatase level in the gingival crevicular fluid. A split-mouth study was conducted in 84 patients who required maxillary canine retraction following first premolar extraction using closed NiTi coil springs, delivering a constant force of 150 grams with Pre adjusted edgewise appliance. Low level laser therapy (LLLT) was done with GaAlAs laser irradiation at 8J/cm2 and 100mW on the canine in the control side for 3 consecutive days. Tartrate Resistant Acid Phosphatase (TRAP) levels were estimated in gingival crevicular fluid (GCF) following irradiation. In the control side TRAP estimation was done in GCF without laser irradiation. Rate of tooth movement was assessed with serial study model analysis over an 8 week period. Result: There was a significantly greater distal movement of the canine irradiated with LLLT at the end of both 4 and 8 weeks. There also was a positive correlation between the increased tooth movement on LLLT side and increased levels of TRAP after the 3rd day. (p value ≤ 0.05). Conclusion: LLLT enhances the rate of orthodontic tooth movement which is also seen histologically by increased TRAP levels