Alveolar socket surface area as a local risk factor for MRONJ development in oncologic patients on polypharmacy

Abstract Objectives To determine the impact of alveolar socket surface area and number of root extractions for developing medication-related osteonecrosis of the jaw (MRONJ) in polypharmacy patients following multiple tooth extractions. Materials and methods A retrospective sample of 40 patients was recruited, including 20 polypharmacy patients (109 tooth extractions) who developed MRONJ in at least one of the extraction sites, matched with 20 controls (100 tooth extractions). Tooth-specific alveolar socket surface areas were assessed using CBCT scans from the control group to establish reference values for alveolar socket surface areas in polypharmacy patients with MRONJ. Correlations between the number of extracted tooth roots, alveolar socket surface area, and development of MRONJ were analysed within the polypharmacy group. Results 40% of tooth extractions in polypharmacy patients undergoing multiple extractions resulted in the development of MRONJ, with a higher prevalence observed in the mandible (44%). Among the extracted mandibular tooth roots, half were susceptible to MRONJ, and 45% of the exposed socket surface area was affected. Both jaws showed an increased risk (20%) of MRONJ following molar extraction. A strong positive correlation existed between extraction sites that developed MRONJ and both the number of mandibular tooth roots extracted (r = + 0.861; p < 0.001) and the total exposed alveolar socket surface area (r = + 0.757; p < 0.001). However, no significant correlations were observed in the upper jaw. Conclusions This study is the first to demonstrate that both mandibular alveolar socket surface area and number of extracted tooth roots are positively related to extraction sites developing MRONJ in polypharmacy patients undergoing multiple tooth extractions. Clinical relevance Identifying high-risk patients and implementing preventive strategies can reduce MRONJ incidence, underscoring the need for careful management of polypharmacy patients, especially those undergoing mandibular tooth extractions.