Conclusion

The findings of this systematic review and meta-analysis reinforce the multifactorial nature of ORNJ and highlight a broad range of associated risk factors. Oral cavity, smoking, dental extractions, oropharyngeal tumors, and tumor stages T2 and T4 were associated with an increased risk of ORNJ, whereas good oral hygiene was identified as a protective factor. These findings contribute to a better understanding of the development and progression of the disease and may support early diagnosis, risk stratification, and individualized therapeutic planning. Nevertheless, prospective studies with robust methodologies and standardized diagnostic and radiological criteria are still needed to establish more precise strategies for the prevention, monitoring, and management of ORNJ, thereby reducing its incidence and severity among patients undergoing radiotherapy.