Osteoradionecrosis Rate in Patients Undergoing Radiotherapy for Head and Neck Cancer Treatment: A Six Months Follow-Up of a Perspective Clinical Study ^†

High-dose radiotherapy (RT) for head and neck cancer has significant adverse effects on maxillofacial tissues, among which osteoradionecrosis (ORN) is the most severe and potentially life-threatening. Although tooth extractions seem to be the main risk factor, few perspective studies evaluated protocols to minimize the ORN risk due to extractions [1]. The aim of this study is to evaluate incidence and risk factors of ORN in a cohort of patients receiving tooth extractions before RT and evaluate an algorithm about extraction decision.

One-hundred and twenty-eight patients were recruited in this study: impacted third molars with radiographic sign of pericoronitis, teeth with periapical lesions, unrestorable teeth, periodontally compromised teeth (pocket probing depth > 5 mm, clinical attachment loss > 8 mm, grade 2 tooth mobility, II grade furcation involvement) were extracted under antibiotic prophylaxis.

A 15-days interval between the last tooth extraction and the beginning of RT was recommended. Patients were visited at 15 days, 1, 3 and 6 months after the beginning of RT. Data of patients with a minimum of 6 months follow-up are presented in this report.

ORN was defined as irradiated exposed necrotic bone, without healing for 3 months, in absence of cancer recurrence, and staged according to Notani et al. [2]. RT treatment plan were reviewed, and each post-extractive socket was contoured with the software Eclipse Treatment Planning System (Varian Medical System). The dose received by each socket was finally calculated. The protocol was approved by the Ethic Committee of Catholic University–Fondazione Policlinico Gemelli (Prot. OHHN-1, ID-2132).

Out of 128 patients, 64 had a 6 months follow-up, 41 of whom received at least one tooth extraction, for a total of 183 teeth. Twenty-one days was the mean time interval before the beginning of RT. Three sites in 3 different patients (7.3% of patients) developed ORN, all in the posterior mandible and two of them also received chemotherapy.

Tooth extraction has been recognized as a risk factor for the development of ORN, especially in the posterior mandible. In the preliminary results of our study, 3 ORN happened and the major risk factor was the anatomical site. These results are consistent with the current literature, suggesting that the proposed protocol can be a valid support in the decision-making process. Since ORN can be a late onset complication of RT, a longer follow-up must be performed to draw definitive conclusions.