A Retrospective Cohort Study of Medication-Related Osteonecrosis of the Jaw (MRONJ) Prevention.

PURPOSE: Medication-related osteonecrosis of the jaw (MRONJ) is a serious complication that can arise in patients receiving antiresorptive or antiangiogenic therapy. Despite known predisposing factors, effective prophylaxis is currently little used. We therefore sought to assess the standardised prevention protocols that are used in our institution for reducing MRONJs among at-risk patients and to quantify the consistency of the effects. METHODS AND MATERIALS: This retrospective cohort study analysed 422 dental extraction records from 126 patients who had received antiresorptive or antiangiogenic therapy. The extractions were classified into four risk levels based on medication class, cumulative treatment duration, comorbidity burden and immunosuppression status. The effect of the prevention protocol was estimated using Mantel-Haenszel stratified analysis, with the risk level as the stratifying variable, and the homogeneity of the effect was assessed using the Breslow-Day test. RESULTS: MRONJ developed in 94.1% of extractions performed without prevention protocols and in only 6.7% with prophylactic protocols; Mantel-Haenszel stratified analysis - adjusting for the baseline risk level - produced a common OR of 0.0044 (95% CI: 0.0010-0.0195, p 0.0001). Stratum-specific estimates were consistent across all three risk levels, and the Breslow-Day test confirmed the homogeneity of the effect. CONCLUSIONS: Mantel-Haenszel stratified analysis confirmed consistent protective effects of the applied prevention protocols, with different proportionality, across every risk level. This study proposes the first stratified quantification of prevention protocol effectiveness across a validated composite risk scoring system.