ABSTRACT
Aim: This study aimed to evaluate the effect of low-level laser therapy (LLLT) associated to mineral trioxide aggregate (MTA) on the alveolar bone repair process. Methods: Forty Wistar rats had the upper right incisor extracted and were assigned to 4 groups according to the treatment of the alveolar wound: G1 - no treatment (control group); G2 - sockets were filled with MTA; G2 - sockets were treated with LLLT(l780 nm, 40 mW, 16 J/cm2); and G4 sockets were treated with LLLT and filled with MTA. The animals were sacrificed 14 days after the surgical procedures. The maxillas were removed, fixed in formalin, decalcified in 0.5% nitric acid and processed histologically. Results: In G1, there was bone formation on the bottom of the socket, but it was not noticeable on the superficial areas, as well as the presence of an intense granulation tissue. In G2, the bone trabeculae were irregular and thin, and were associated with intense vascular hyperemia and chronic inflammation. In G3, there was substantial formation of thick interwoven osteocyte-rich trabecular bone, with an evident osteoblastic rimming. In G4, it was observed an intense deposition of thin irregular bone trabeculae, but vascular hyperemia was quite distinguishable. Conclusion: LLLT was the most successful treatment to improve alveolar bone repair.