Influence of zoledronic acid and low-intensity laser on collagen fibers during the bone repair process

Purpose: To evaluate collagen fibers during the bone repair process in critical defects created in the tibias of rats, treated with zoledronic acid (AZ) associated with low-level laser therapy (LLLT).

Methods: Ten rats were distributed according to treatment: group 1) saline solution; group 2) LLLT; group 3) AZ; group 4) AZ and LLLT. AZ was administered at the dose of 0.035 mg/kg at fortnightly intervals over eight weeks. Next, 2-mm bone defects were created in the tibias of all animals. The bone defects in groups 2 and 4 were irradiated LLLT in the immediate postoperative period. After periods 14 and 28 of application, the animals were euthanized, and birefringence analysis was performed.