Dental management prior to radiotherapy is often time-critical, and there are no studies on whether manipulations such as tooth extraction influence the risk of severe radiation-induced oral mucositis (ROM) during radiotherapy. Therefore, the aim of this study was to describe the relationship between dental management and the incidence of severe ROM.

A retrospective analysis was conducted on 144 head and neck cancer (HNC) patients who received dental management before radiotherapy at Peking University Cancer Hospital, from January 2016 to December 2017. Demographic characteristics, primary tumor features, cancer treatment characteristics, and severity of oral mucositis during radiotherapy were recorded. Univariate analysis and logistic regression analysis were used to explore factors associated with severe radiation-induced oral mucositis.

The incidence of grade 3 mucositis was 14.5% (22/144); univariate analysis showed that the number of extracted teeth (OR = 1.313; 95%CI = 1.012–1.702; P = 0.040) and patients with primary oral cancer had a higher risk of developing grade 3 mucositis (OR = 3.848; 95% CI = 1.508–9.822; P = 0.005). No statistical correlation was found between pre-radiation therapy prophylaxis, dental restoration, endodontic treatment, and grade 3 mucositis (P > 0.05). Logistic regression analysis showed that the number of extracted teeth (OR = 1.421, 95%CL = 1.071–1.885, P = 0.015) and primary tumor location in the oral cavity (compared with other head and neck cancers) (OR = 5.165, 95%CL = 1.636–16.311, P = 0.005) were significantly associated with grade 3 mucositis.

In HNC patients undergoing radiotherapy, the primary site located in the oral cavity and a higher number of teeth extracted are independent risk factors for the development of severe mucositis.