Abstract

Purpose: This study evaluated the pathological effects of single posterior implant-supported fixed prostheses on adjacent and antagonistic teeth and investigated the influence of systemic diseases, occlusal conditions, implant site, and patient sex.Materials and Methods: A retrospective observational study was conducted on 100 patients who had received a single posterior implant and were followed for at least one year at Gangneung-Wonju National University Dental Hospital. Clinical and radiographic assessments compared adjacent and antagonistic teeth at the implant site (ex-perimental group) with the corresponding contralateral teeth (control group). Parameters included tooth cracks, cusp fractures, alveolar bone status, treatment history, and occlusal contact assessed using the Shimstock test. Associations with systemic diseases, occlusal contact, sex, and implant position were also analyzed. Statistical analysis was performed using the chi-square test with a significance level of 0.05. Results: The distal adjacent tooth at the implant site showed significantly higher mobility than the control group (p<0.05). In patients without unilateral mastication, periapical lesions in antagonistic teeth (p<0.05) and cracks in adjacent teeth (p<0.05) were more frequent. Diabetic patients demonstrated a significantly higher prevalence of alveolar bone loss and treatment history in both adjacent and antagonistic teeth (p<0.05). When no occlusal contact was present on the implant-antagonistic tooth, less alveolar bone loss was observed (p<0.05), whereas cusp fractures in adjacent teeth were more common. Male patients showed a higher frequency of cusp fractures and cracks in adjacent teeth (p<0.05). Conclusion: Single posterior implant-supported fixed prostheses can induce pathological changes in adjacent and antagonistic teeth. Implant treatment planning should consider systemic health, occlusal dynamics, sex-related differences, and long-term maintenance. (J Korean Dent Assoc 2025; 63(12): 381-390)