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

Background

Advanced 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.

Purpose

The 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, Sample

This 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 Variable

The primary predictor variable was viability of resection margins on histopathologic analysis (viable or nonviable). Secondarily, other risk factors categorized as demographic (age, sex, race), medical (comorbidities), and perioperative (reconstructive modality, antibiotic duration, microbiological growth) were evaluated.

Main Outcome Variable

The 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.

Covariates

Not applicable.

Analyses

Descriptive and bivariate statistics were used to identify associations between risk factors and time to infection recurrence. A significance level of P ≤ .05 was considered significant.

Results

The 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 1 and 2 year survival of 75.8 and 66.2%, respectively. Nonviable resection margins were associated with earlier time to infection recurrence (P ≤ .001, hazard ratio (HR) = 11.9, 95% confidence interval (CI) = 3.84 to 36.7) as was younger age (P = .005, HR = 0.921, 95% CI = 0.869 to 0.976) and atypical pathogen growth on culture (P = .002, HR = 8.58, 95% CI = 2.24 to 32.8).

Conclusions and Relevance

Histopathologic 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.