Comparison of the Clinical Characteristics of Bisphosphonate-associated Osteonecrosis of the Jaw with Inflammation-associated Osteonecrosis of the Jaw in Patients with Osteoporosis and Benign Diseases

Abstract

Objectives: Osteonecrosis of the jaw (ONJ) involving the use of bisphosphonates is referred to as bisphosphonate-associated ONJ (BONJ). Inflammation also can cause ONJ and it may be called inflammation-associated ONJ (IONJ). The aim of this study was to compare clinical characteristics between BONJ and IONJ. Materials and

Methods: Medical records at the Ajou University Hospital were reviewed using key words “osteonecrosis”, “sequestrum”, and “dead bone” of the mandible and maxilla. Eighteen patients diagnosed with ONJ were identified from January 2003 to December 2009. Using criteria from the American Association of Oral and Maxillofacial Surgeons, 12 cases were diagnosed as BONJ and six as IONJ. Clinical characteristics and treatment modalities, outcomes of two groups of patients were investigated.

Results: Patients of the BONJ group were older than those of IONJ group (median: 76.5 years vs. 60 years). In the BONJ group, mandible was more commonly involved sites and percentage of diabetic patients was higher. Three of 12 (25%) BONJ patients received oral glucocorticoids, while none of the IONJ patients. Ten (83.3%) of the BONJ cases and 2 (33.3%) of the IONJ cases were triggered by dental extractions. Though duration of ONJ treatment was longer in the BONJ group than the IONJ group (6.4±5.2 months vs. 2.9±1.9 months), both groups eventually showed good prognosis.

Conclusions: ONJ may occur in the absence of bisphosphonate. BONJ occurred in older patients, and needed longer treatment duration compared to IONJ. Prognosis of ONJ was relatively good.