Bone turnover and inflammatory markers of bisphosphonate-related osteonecrosis of the jaw in female osteoporosis patients

Objective: This study aimed to analyze the difference in biochemical markers of patients with osteoporosis taking bisphosphonates (BPs) who developed bisphosphonate-related osteonecrosis of the jaw (BRONJ) vs those who did not develop BRONJ. Patients & methods: Forty-one BRONJ patients and 76 control patients who had been treated with alendronate or risedronate were investigated. Bone turnover markers [C-terminal telopeptide (CTX) and bone-specific alkaline phosphatase (bALP)] and inflammatory activity markers [erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) level] were evaluated. In BRONJ patients, radiographic severity and its relation with the serological data and BRONJ staging were analyzed. Results: CTX and bALP level after the long-term BPs treatment in the control patients was similar to the level of the BRONJ patients at the time of diagnosis. The BRONJ patients showed a significantly higher ESR than the control patients with BPs. BRONJ score were not correlated with CTX and bALP. The severity of BRONJ in alendronate-treated group was strongly correlated with ESR and CRP. Conclusions: Bone turnover markers such as serum CTX level has limitation in reflecting BRONJ status. Increased level of inflammatory markers in BRONJ patients implies the importance of inflammation in BRONJ progression.