Reliability of early stage symptoms/clinical findings of osteonecrosis of the jaw: Japanese Osteoporosis Intervention Trial-05 (JOINT-05).

Introduction: To investigate the differences in the incidence rates of suspected stage 0/1 osteonecrosis of the jaw (ONJ) and incidence risk of relevant clinical findings of suspected stage 0 ONJ between patients treated with sequential therapy comprising weekly teriparatide for 72 weeks followed by alendronate for 48 weeks vs. those who received monotherapy with alendronate for 120 weeks.

Materials and methods: Suspected stage 0/1 ONJ was defined by non-specific symptoms. Tooth mobility and periodontal symptoms (gingival bleeding, swelling, and/or pain) were selected as clinical findings of suspected stage 0 ONJ. Poisson regression models were applied to calculate the incidence rate ratios of suspected stage 0/1 between the teriparatide group (TG) and alendronate group (AG). Generalized linear models were used to calculate the risk ratios of clinical findings between groups.

Results: Two hundred and sixty-one participants in the TG and 344 in the AG answered a structured questionnaire on oral health and were included in this study. There were no significant differences between the groups in the incidence rate of suspected stage 0/1 ONJ at both 72 and 120 weeks. The risk ratio of the TG to AG for tooth mobility was 0.34 (95% confidence interval [CI] 0.13-0.88, p = 0.02) at 72 weeks and 0.90 (95% CI 0.40-2.03, p = 0.83) at 120 weeks. The incidence rate of tooth mobility related to periodontal symptoms decreased in the TG and increased in the AG during the study.

Conclusion: Tooth mobility accompanied by clinical periodontal symptoms may be a useful early sign of stage 0 ONJ.