Objectives: The aim of this study was to determine the influence of patient-related systemic factors, local bone and intraoral factors, and implant-related factors on peri-implant marginal bone loss (MBL). Method and materials: The following data were collected from patients who received dental implants and were recalled for examinations at least 3 years after treatment completion: medical history, age, sex, habits, periodontal health, implant size and surface, surgical procedure, prosthesis type, implant failure, Plaque Index, and oral hygiene. MBL was investigated using both baseline and follow-up panoramic radiographs. Results: The study included 1,126 dental implants placed in 304 patients (185 [60.9%] women and 119 [39.1%] men). The mean age was 54.30 ± 13.52 years (range 22 to 83 years). The mean follow-up period was 58.8 ± 11.2 months. The MBL was observed in 271 (24.1%) implants, of which 160 (14.2%) were ≤ 2 mm and 111 (9.9%) were > 2 mm. Respective mean MBL values on mesial and distal sides were 0.42 ± 1.03 mm and 0.42 ± 1.02 mm. Of the implants, 19 (1.7%) were lost, leading to an implant success rate of 98.3%. Age, history of hysterectomy, history of periodontitis, oral hygiene, abrasions, smoking, implant location, implant surface, implant length, surgical procedure type, and prosthesis type were all found to be statistically significant for MBL (P .05). Certain combinations of these factors resulted in increased MBL. Conclusion: In the present study, local factors had more significant effects on MBL than did systemic factors, and combinations of these factors had greater effects on MBL. Keywords: clinical evaluation, dental implants, local and systemic factors, marginal bone loss, radiologic evaluation