Systematic Review of Late Dental Effects Following Head and Neck Radiation Therapy in Childhood Cancer Survivors

Purpose: Childhood cancer survivors face an increased risk of dental anomalies with both chemotherapy and radiation therapy (RT) contributing to these late adverse effects (AEs), particularly when RT doses >20 Gy are delivered. This systematic review aims to: (1) provide an overview of late dental AEs reported after childhood RT, (2) report the prevalence of these AEs in survivors who received head and/or neck RT during childhood, and (3) describe dose-response evidence and the use of AE grading protocols. Methods and Materials: A comprehensive search was conducted in Embase and PubMed. Extracted data included study characteristics, treatment details, and outcomes. Heterogeneity was assessed qualitatively, and risk of bias was evaluated using the Cochrane Childhood Cancer tool. Results: Forty-four studies published between 1985 and 2024 were included, comprising 7299 participants (age range 3-16.5 years). The median prescribed RT dose was 50.4 Gy (range 10.0-67.5 Gy), with a median follow-up of 8.35 years. Reported dental AEs included agenesis, microdontia, and root stunting. Higher prescribed radiation doses were associated with increased AE risk. Dental outcomes were assessed clinically and radiographically. Conclusions: There is a clear need for standardized definitions, assessment methods, grading criteria, and data reporting for late dental AEs in childhood head and/or neck cancer survivors. Accurate documentation of RT regimens and pretreatment dental status is essential to support dose minimization strategies, tailored patient education, and long-term dental follow-up, ultimately improving survivorship care.