Аннотация
A BSTRACT Background: Medication-related osteonecrosis of the jaw (MRONJ) is one of the most severe complications associated with long-term bisphosphonate therapy in oncology patients. Zoledronic acid, widely used for the management of metastatic bone disease, may lead to progressive mandibular destruction, chronic infection, and significant impairment of quality of life. Despite increasing clinical relevance, data regarding radiological manifestations and infectious complications of MRONJ remain limited. Objective: To evaluate the clinical, laboratory, and radiological characteristics of medication-related osteonecrosis of the mandible in patients receiving zoledronic acid therapy for metastatic malignancies. Materials and Methods: A retrospective observational clinical study was conducted in the Department of Oral and Maxillofacial Surgery, Aktobe, Kazakhstan, during 2024. The study included 11 hospitalized patients with MRONJ associated with intravenous zoledronic acid therapy complicated by secondary infection and osteomyelitis. Clinical examination, laboratory investigations, panoramic radiography, and computed tomography (CT) were performed in all patients. Descriptive statistical analysis was used for data evaluation. Results: Tooth extraction was identified as the main triggering factor for MRONJ development in 91.0% of patients. The predominant clinical manifestations included exposed necrotic bone (100%), persistent pain syndrome (100%), soft tissue inflammatory infiltration (100%), halitosis (90.9%), suppuration (81.8%), and trismus (72.7%). Laboratory findings demonstrated leukocyte abnormalities, anemia, thrombocytopenia, hypoproteinemia, and secondary immune deficiency. CT imaging revealed diffuse mandibular osteolysis, cortical destruction, trabecular disorganization, sequestration, and osteosclerotic changes. Secondary infection and chronic osteomyelitis contributed to disease progression and prolonged clinical course. Conclusion: MRONJ associated with zoledronic acid therapy demonstrates aggressive chronic progression characterized by extensive mandibular destruction and infectious complications. Tooth extraction remains the principal triggering factor. Early dental prevention, continuous monitoring, and radiological assessment are essential for reducing MRONJ risk and improving patient outcomes.