Photodynamic therapy and photobiomodulation therapy in zoledronic acid-induced osteonecrosis in rats

•Antimicrobial photodynamic therapy and photobiomodulation therapy attenuated the severity of osteonecrosis of the jaws.•Antimicrobial photodynamic therapy and photobiomodulation therapy promote a reduction of bone necrosis extension.•Antimicrobial photodynamic therapy and photobiomodulation therapy promote a reduction of inflammatory parameters. This study investigated the effect of antimicrobial photodynamic therapy (PDT), using methylene blue (MBO) and photobiomodulation therapy (PT), on the alveolar bone of rats submitted to bisphosphonate-induced osteonecrosis of the maxillaries (OMB) model using zoledronic acid (ZA). Sixty rats divided into six groups were used: SALINE, PDT, ZA, ZA+PDT, ZA+PT, and ZA+MBO. Three weekly administrations (Days 0, 7, and 14) of ZA 0.20 mg/kg or saline solution were performed. After one month (Day 42), the exodontia of the left lower first molars were performed. An additional dose of ZA was administered at Day 49. PDT was performed on days 42, 45, 49, and 54. One month after exodontia (Day 70), the animals were euthanized to obtain samples for imaging and microscopic analysis. ANOVA/Bonferroni tests were used for statistical analysis. The ZA+PDT group showed a significantly lower percentage of apoptotic osteocytes than the ZA group (p