Abstract
BACKGROUND: The primary aim of this retrospective study was to determine the prevalence of peri-implant bone loss in patients with a documented history of periodontal disease. The secondary aim was to evaluate the influence of various demographic, systemic, and prosthetic variables on marginal bone level changes. MATERIAL AND METHODS: A retrospective analysis was conducted on a cohort of 261 patients treated with implant-supported prostheses at the Rey Juan Carlos University Clinic between 2018 and 2023. Anonymised data were extracted from clinical records and radiographic archives. Variables analysed included age, sex, smoking status, diabetes mellitus, type of prosthesis, use of transepithelial abutments, implant brand, and periodontal history. Bone loss was categorised as none, <1.5 mm, or >1.5 mm. Statistical analysis employed descriptive statistics, Kolmogorov-Smirnov tests for normality, and non-parametric tests (Kruskal-Wallis and Chi-square) using IBM SPSS Statistics, version 25.0. RESULTS: The overall prevalence of peri-implant bone loss was 24.5%. Within the cohort with a periodontal history (60.5% of patients), the prevalence was 14.5%. Statistical analysis revealed that only the use of a transepithelial abutment (p=0.000) and the implant brand (p=0.001) demonstrated a statistically significant influence on bone loss levels. No significant associations were found with a history of periodontitis alone, age, sex, diabetic status, smoking habit, or type of prosthetic restoration. CONCLUSIONS: Within the limitations of this study, a history of periodontal disease was not a determining factor for increased peri-implant bone loss. The findings underscore the critical importance of prosthetic design, specifically the use of transepithelial abutments, and implant selection in ensuring favourable medium-term outcomes. These results suggest that stringent periodontal therapy and maintenance protocols may mitigate the inherent risks in this patient population.