Timing for Radiotherapy Initiation After Dental Extraction and Risk of Osteoradionecrosis in Head and Neck Cancer Patients: A Systematic Review and Meta‐Analysis

ABSTRACT Background Head and neck cancer (HNC) patients are advised to undergo dental extraction of teeth with poor prognosis prior to radiotherapy (RT) initiation to prevent osteoradionecrosis (ORN). However, insufficient healing time may result in persistent extraction wounds during RT, which constitute a potential risk factor for ORN, whereas excessive delay in RT initiation may compromise cancer control. Objectives To identify an optimal healing period between pre‐RT dental extraction and RT initiation to minimize ORN risk in HNC patients. Methods This systematic review and meta‐analysis were conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) guidelines and the Meta‐analysis of Observational Studies in Epidemiology (MOOSE) framework, with a pre‐specified PROSPERO registration (ID: CRD42024586754). The Newcastle–Ottawa Scale was employed to assess the quality of included studies. Patients were stratified into ≤ 7 days versus > 7 days and ≤ 14 days versus > 14 days groups based on the interval between dental extraction and RT initiation. Subgroup analyses were performed by geographic population. Results Eight retrospective cohort studies involving 47,527 HNC patients and 2863 ORN cases were included. No significant association was observed between the timing of pre‐RT dental extraction and ORN risk in the overall population (OR = 0.99, 95%CI: 0.67–1.47), with significant heterogeneity ( I ² = 92%, τ ² = 0.2079, p < 0.01). In Western populations, patients initiating RT within < 7 days or < 14 days after dental extraction demonstrated significantly elevated ORN risk (OR = 3.07, 95%CI: 1.52–6.21 and OR = 2.01, 95%CI:1.10–3.68, respectively). Conclusion An insufficient healing interval between dental extraction and RT initiation may significantly increase ORN risk, particularly in specific population subgroups.