Oral Bisphosphonate-Induced Osteonecrosis: Risk Factors, Prediction of Risk Using Serum CTX Testing, Prevention, and Treatment

Purpose: To assess the risk and time course of oral bisphosphonate-induced osteonecrosis of the jaws. Materials and Methods: Detailed data from 30 consecutive cases were compared with 116 cases due to intravenous aminobisphosphonates. Results: Results in part noted a higher incidence related to alendronate (Fosamax; Merck, Whitehouse Station, NJ), a 94.7 % predilection for the posterior mandible, and a 50 % occurrence spontaneously, with the remaining 50 % resulting from an oral surgical procedure, mostly tooth removals. Just over 53 % of patients were taking their oral bisphosphonate for osteopenia, 33.3 % for documented osteoporosis, and 13.4 % for steroid-induced osteoporosis related to 4 or more years of prednisone therapy for an autoimmune condition. There was a direct exponential relationship between the size of the exposed bone and the duration of oral bisphosphonate use. There was also a direct correlation between reports of pain and clinical evidence of infection. The morning fasting serum C-terminal telopeptide (CTX) test results were observed to correlate to the duration of oral bisphosphonate use and could indicate a recovery of bone remodeling with increased values if the oral bisphosphonate was discontinued. A stratification of relative risk was seen as CTX values less than 100 pg/mL representing high risk, CTX values between 100 pg/mL and 150 pg/mL representing moderate risk, and CTX values above 150 pg/m