Potential Role of Oral Microbiota in Medication-Related Osteonecrosis of the Jaw in Cancer Patients: A Narrative Review.

Medication-related osteonecrosis of the jaw (MRONJ) is a severe complication frequently observed in cancer patients undergoing antiresorptive therapies, such as bisphosphonates and denosumab. Emerging evidence suggests that dysbiosis of the oral microbiota plays a pivotal role in the pathogenesis of MRONJ. The complex interplay between microbial communities, host immune responses, and the effects of cancer treatments creates an environment conducive to pathogenic colonization, chronic inflammation, and impaired bone healing, which are the key hallmarks of MRONJ. Chemotherapy, radiotherapy, and antiresorptive agents significantly disrupt oral microbiota homeostasis, reducing microbial diversity and the overgrowth of opportunistic pathogens. These alterations exacerbate the inflammatory responses, accelerate bone resorption, and impede tissue repair. The identification of specific microbial biomarkers associated with MRONJ could facilitate early detection and targeted interventions, such as antimicrobial and probiotic therapies, to restore the microbial balance and mitigate the risk of MRONJ. Furthermore, the implementation of personalized preventive protocols, including rigorous oral hygiene and multidisciplinary collaboration among oncologists, dentists, and microbiologists, is critical for reducing the incidence and severity of MRONJ in high-risk populations. Future research should focus on elucidating the mechanisms by which microbial dysbiosis contributes to MRONJ, validating microbiome-based diagnostic tools, and optimizing therapeutic strategies to preserve oral and systemic health in patients with cancer. Integrating microbial ecology into the MRONJ management framework offers a promising avenue for addressing this challenging condition and improving the outcomes for vulnerable individuals.