Medication-related osteonecrosis of the jaw primary prevention: multidomain long-term intervention versus pre-bisphosphonate treatment standalone dental intervention. A retrospective multi-center comparative cohort study

Purpose: Medication-related osteonecrosis of the jaw (MRONJ) is a serious adverse drug reaction mostly associated to the use of bone-modifying agents. Preventive dental strategies aim to reduce its risk, but the comparative benefit of structured long-term interventions versus a single pre-treatment dental visit remains unclear. This study assessed the impact of a structured long-term, multidomain dental prevention protocol compared with a single baseline dental assessment in patients receiving an oncological-based, high dose (HD) regime of Zoledronic acid (ZA). Methods: Between 2012 and 2015, two Southern Italian university hospitals enrolled adult cancer and myeloma patients initiating ZA. Participants received either the Standard Protocol (SP), a single pre-treatment dental visit, or the Intensive Protocol (IP), which added scheduled follow-ups and periodontal care. MRONJ was diagnosed using SICMF-SIPMO clinical and radiological criteria. Results: 202 patients (M/F = 83/119; mean age 63.3 years), were stratified into a SP group (n = 115) and an IP group (n = 87). Eighteen patients developed MRONJ (8.9%). The MRONJ frequency was significantly higher in the SP group (13.9%) compared to the IP group (2.3%) (p = 0.004). MRONJ cases in the SP group showed poorer oral hygiene, a higher rate and severity of periodontitis alongside, and higher post-extraction onset rate. Conclusion: Multidomain dental prevention long-term protocol was found to be effective in reducing the incidence of MRONJ by ZA therapy, compared to a single pre-therapy dental intervention, with a potential change of case characteristics. These findings support integrating routine dental evaluation and periodontal maintenance into cancer and myeloma care pathways to improve patient safety and oral outcomes.