Risk Factors for Infection Recurrence After Surgical Resection of Advanced Stage Osteonecrosis of the Mandible

Abstract

BackgroundAdvanced stage osteoradionecrosis (ORN) and medication-related osteonecrosis of the jaw (MRONJ) are challenging disease entities requiring multimodal therapy including surgical resection. However, risk factors associated with infection recurrence are poorly understood. PurposeThe purpose of this study was to identify risk factors associated with infection recurrence following resection of advanced stage ORN or MRONJ of the mandible. Study design, setting, sampleThis was a retrospective cohort study including patients who underwent segmental mandibulectomy for management of ORN or MRONJ between 2016 and 2021 at the authors’ institution. Subjects who did not have margin viability data were excluded. Predictor/exposure/independent variableThe primary predictor variable was viability of resection margins on histopathologic analysis (viable or non-viable). Secondarily, other risk factors categorized as demographic (age, sex, race), medical (comorbidities), and perioperative (reconstructive modality, antibiotic duration, microbiological growth) were evaluated. Main outcome variableThe primary outcome variable was time to infection recurrence defined as time from surgical resection to clinical diagnosis of a fistula tract, abscess, or persistent inflammatory symptoms necessitating surgical intervention. CovariatesNot applicable. AnalysesDescriptive and bivariate statistics were used to identify associations between risk factors and time to infection recurrence. A significance level of p ≤ 0.05 was considered significant. ResultsThe cohort consisted of 57 subjects with a mean age of 63.3 ± 10.0 years (71.9% Male, 75.4% White) treated for ORN (47.4%) or MRONJ (52.6%). A total of 19/57 (33%) subjects developed a recurrence of infection with one and two year survival of 75.8% and 66.2%, respectively. Non-viable resection margins were associated with earlier time to infection recurrence (p ≤ 0.001, Hazard Ratio (HR) = 11.9, 95% Confidence Interval (CI) = 3.84 – 36.7) as was younger age (p = 0.005, HR = 0.921, 95% CI = 0.869 – 0.976) and atypical pathogen growth on culture (p = 0.002, HR = 8.58, 95% CI = 2.24 – 32.8). Conclusions and RelevanceHistopathologic margin viability was associated with earlier time to infection recurrence following resection of advanced stage ORN or MRONJ of the mandible. Additional studies are needed to identify interventions that may improve outcomes in this demographic.