Osteonecrosis of the jaw and bisphosphonate therapy: Experience from a single Italian institution

Abstract

19661 Background: Osteonecrosis of the jaw (ONJ) is reported as serious side-effect after bisphosphonate (B) therapy. Although the number of patients (pts) presenting with ONJ seems to be increasing, the exact prevalence and etiology of osteonecrosis are not well established because of heterogeneous of clinical reports. Methods: From May 2005 and October 2006, 12 cases of ONJ were diagnoses at our Institution. Results: Characteristics of patients: the median age at presentation of ONJ was 64.2 years (range 43–79); 9 pts were female and 3 pts were male. All pts were treated with Zoledronic acid, none of pts were pretreated with other B. Location of necrosis was mandible and maxilla. Presenting symptoms were: parondotosis disease, bone exposure and ulceration. Osteonecrosis was preceded by dental extraction in 5 pts (45%). The diagnosis of ONJ was: clinical (exposed bone) and radiological in all pts; the biopsy was performed in 3 pts, none of wich showed the presence of neoplastic disease. The treatments of ONJ were: antibiotic in 3 pts, partial maxillectomiy in 2 pts, curettage in 8 pts. Only 1 pts was documented residual sites of necrosis after surgical malignancies. All pts are alive at the time of this report, with except of one. Characteristics of malignancies: breast cancer 7 pts, prostate cancer 2 pts, multiple myeloma 1 pts, carcinoma of unknown primary 1 pts. Concomitant or previous therapies for malignancies were: chemotherapy and/or radiotherapy in all pts. None of pts received radiotherapy to the involved region. B therapy has been continued in about half pts, irrespective previously ONJ, without worsening clinical condition. Conclusions: In our experience the number of pts with previous history of dental extraction and subsequent ONJ during B therapy is consistent as described in many reports. This condition may represent an important risk factor for developing osteonecrosis correlated with prolonged infusion of B. In order to reduce incidence and serious side effects of B therapy, we adopted alternative schedule treatment with bi or tri - monthly infusion. No significant financial relationships to disclose.