Important aspects regarding the role of microorganisms in bisphosphonate-related osteonecrosis of the jaws

• Actinomyces is the most frequent microorganism found in BRONJ lesions.
• Bacterial biofilm plays an essential role in BRONJ repercussion.
• Treatment cannot ignore the different species found in BRONJ.

Bisphosphonate-related osteonecrosis of the jaws (BRONJ) is an important side effect of bisphosphonates, whose etiopathogenesis has not been completely elucidated. Theories pointing to bone turnover and angiogenesis inhibition, as well as effects on epithelial cells of oral mucosa and the role of microorganisms have been reported. Nevertheless, the true contribution of each one of these factors to BRONJ is unknown. We present here a literature review focusing on important aspects regarding the role of microorganisms in BRONJ development. Knowledge about specific microbiota and its role in the etiopathogenesis of this disease can help the optimisation of preventive and therapeutic interventions in patients with or at-risk for BRONJ.