Method: Doses used were: DE:25J/cm2/3 points/T= 7 sec/0,7J per point/ 2,1J total energy (low dose) and DE:580J/cm2/6 points/T=163 sec/ 16J energy per point/ 96J total energy (high dose), comparing with control group (no treatment or no irradiation). The first upper left molar was moved with 25 grams of force applied using NiTi coils. Low level laser (LLLI) was applied on three points in each animal with 48 hours of intervals, totalizing three irradiations. The distance between the distal surface of the first molar and the mesial surface of the second molar was measured by means of the images obtained directly on jaw dissected with portable Digital Microscope Dino-Lite and the measures were done with DinoCapture 2.0 software. The analysis of variance followed by Tukey multiple comparison tests (p<0.05) were used to compare the groups.
Result: The results showed no statistically significant differences comparing control group with high-dose irradiated group, but statistically significant differences comparing control group with the low-dose irradiated group. The findings of the present study imply that the amounts of orthodontic tooth movement are increased, after LLLI with low doses, while LLLI with high doses, there are not increase movement.
Conclusion: It could be concluded that LLLI with low dose can heighten the speed of teeth movement in orthodontic treatments, and LLLI with less or more energies maybe shows different results.