Abstract
Introduction Medication-related osteonecrosis of the jaw (MRONJ) is a rare and debilitating multi-factorial condition, characterized by non-healing exposed bone in the maxillofacial region. According to the 2022 American Association of Oral and Maxillofacial Surgeons (AAOMS) position paper, the diagnosis of MRONJ requires the presence of current or previous treatment with antiresorptive or antiangiogenic drugs, presence of visible or probe-able exposed bone in the maxillofacial region for over eight weeks, in the absence of radiotherapy or metastatic disease to the jaws. In 2003, Marx reported the first cases of osteonecrosis of the jaws in patients receiving bisphosphonates (BPs) treatments, which was subsequently recognized as bisphosphonate-related osteonecrosis of the jaw (BRONJ). In 2014, the AAOMS renamed the condition MRONJ instead of BRONJ due to the increasing number of patients with osteonecrosis of the jaw related to several other medications. Antiresorptive (particularly BPs and denosumab) or antiangiogenic drugs are commonly related to MRONJ development. These drugs are widely prescribed for managing hypercalcemia of malignancy, spinal cord compression, and pathological fractures associated with bone metastases from tumors such as multiple myeloma, lung, breast, and prostate carcinoma. Also, these medications are used for Paget’s disease of bone, osteogenesis imperfecta, and prevention of fractures in osteoporosis or osteopenia. A staging system for MRONJ according to 2022 AAOMS position paper (Table 1). There are systemic, local, and other risk factors for developing MRONJ (Table 2). Therefore, accurate knowledge about the demographics, clinical characteristics, and predisposing factors of MRON essential for accurate diagnosis and optimal management. Objectives: The purpose of the current study was to evaluate the demographic, clinical characteristics, and risk factors of affected patients with MRONJ diagnosed at Tripoli University Hospital. Methods: This hospital-based retrospective observational study, included patients with a confirmed diagnosis of MRONJ at Tripoli University Hospital, Libya, during the period from January to November 2024. Data were collected from medical records in the Department of Oral and Maxillofacial Surgery, and the Oncology and Hematology Department. Patients with missing information were excluded. The following data were recorded: demographic data, drug-related (type, dose, and route of administration), site of jaw necrosis, disease stage, systemic diseases, smoking habits, medications, and local risk factors associated with MRONJ development. Descriptive statistics were carried out, using IBM SPSS Statistics version 26.0® (IBM Corporation, New York, USA). Results: A total of 10 cases of MRONJ were analyzed (Figures 1 & 2). Of these, 5 (50%) were female and 5 (50%) were male, with an overall female-to-male ratio of 1:1. The patients age at MRONJ presentation ranged from 38 to 85 years, with a mean age of 61.3 years and a standard deviation of 14.945 years. The mandible was the most common site (60%, n = 6), particularly the posterior region (50%, n = 5), while the maxilla was affected in 4 (40%) cases. Disease staging revealed 6 (60%) cases in stage 3, three cases in stage 2, and one case in stage 1. All the patients received intravenous (IV) BPs (zoledronic acid; Zometa®) for the treatment of breast carcinoma (40%, n = 4), prostate carcinoma (50%, n = 5), and multiple myeloma (10%, n = 1), with an average treatment duration of 28 months. Systemic risk factors included diabetes mellitus (four cases) and smoking (one case), while local risk factors were primarily tooth extractions (80%, n = 8), and ill-fitted denture (10%, n = 1). One case (10%) developed spontaneously. Conclusions: MRONJ represents a significant complication in cancer treatment, particularly among older patients receiving IV zoledronic acid. In this study, the posterior mandible was the most commonly affected site, with tooth extraction identified as the primary precipitating factor. Awareness of MRONJ's clinical features and risk factors is essential for general dental practitioners to ensure proper diagnosis, prevention, and appropriate management. Keywords: Osteonecrosis of the jaws, MRONJ, Bisphosphonate.