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

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.