Introduction: Antiresorptive agent-related osteonecrosis of the jaw (ARONJ) is a serious adverse event associated with therapies for advanced cancer involving bone-modifying agents (BMAs). Although many studies have investigated the risk factors for ARONJ, none have provided sufficient clarifications. We aimed to determine whether there is a correlation between tooth extraction before BMA therapy and the development of ARONJ.
Patients and methods: We included 511 patients who were admitted to our department before BMA therapy. The incidence of ARONJ and its risk factors was retrospectively evaluated, focusing on tooth extraction before BMA therapy and radiological findings of the extracted tooth.
Results: Of the 511 patients, 135 underwent tooth extraction before undergoing BMA therapy. ARONJ was observed in 17.7 % and 7.2 % of patients in the extraction and non-extraction groups, respectively (p = 0.0002). Regarding the findings of panoramic radiographs before tooth extraction, the incidence of periapical disease was significantly higher in the ARONJ group than that in the non-ARONJ group (50 % and 27 %, respectively, p = 0.034), and the proportion of bone sclerotic changes in the surrounding teeth was significantly higher in the ARONJ group (58.3 %) than in the non-ARONJ group (24.4 %) (p = 0.0004).
Conclusion: The presence of a hopeless tooth that requires extraction prior to BMA therapy is a risk factor for MRONJ. However, extraction of such teeth should be considered, as this is known to decrease the risk of MRONJ development after BMA therapy initiation. Moreover, the radiological findings of periapical disease and bone sclerotic changes in the extracted teeth identified in this study can be used as novel predictive factors for ARONJ.