A retrospective study on odontogenic and non-odontogenic medication-related osteonecrosis of the jaw: Potential differences in clinical features and treatment outcomes

Abstract

Background/purpose: Local infections, such as periodontal disease or apical lesions, and invasive dental procedures, such as tooth extraction, are thought to trigger medication-related osteonecrosis of the jaw (MRONJ) development. However, some cases of MRONJ develop without any obvious odontogenic triggers. We conducted a retrospective study to clarify the characteristics of non-odontogenic MRONJ. Materials and methods: We retrospectively reviewed data of 229 patients with mandibular MRONJ who underwent surgery. Based on imaging findings, we classified MRONJ as odontogenic MRONJ involving a dental infection and non-odontogenic MRONJ with no dental involvement. Clinical and imaging findings and treatment outcomes of both types of MRONJ were compared. Results: Overall, 193 patients were classified as having odontogenic MRONJ and 36 as having non-odontogenic MRONJ. Non-odontogenic MRONJ was slightly more common among patients with malignancies who received denosumab; however, the difference was not significant. Univariate and multivariate analyses showed that patients with MRONJ with non-odontogenic triggers had significantly poorer treatment outcomes than their counterparts. Conclusion: Non-odontogenic MRONJ exists without the involvement of odontogenic infection as a cause of MRONJ. Compared with that in odontogenic MRONJ, the treatment outcome in non-odontogenic MRONJ is poor. Further studies are required to clarify the true nature of non-odontogenic MRONJ.