[A retrospective cohort study of risk factors for prevalence of implant biological complications].

PURPOSE: To analyze the risk factors of biological complications after implant-fixed denture restoration. METHODS: Seven hundred and twenty-five implants were placed between March 2012 and March 2016. Follow-up period was 5 to 9 years. The implant mucosal index (IMI) and implant marginal bone loss (MBL) were measured at 3 months-1 year, 2-3 years, 4-5 years, 6-7 years and 8-9 years after restoration. The prevalence and risk factors of peri-implantitis and mucositis were analyzed. SPSS 28.0 software package was used to analyze the date. RESULTS: The implant survival rate of 5 years was 98.7%. The prevalence of mucositis and peri-implantitis were 37.5% and 8.3% at 8 to 9 years. Smoking, periodontitis, narrow diameter, rough neck , anterior location, bone augmentation caused higher prevalence of peri-implantitis or mucositis (P＜0.05). CONCLUSIONS: Smoking, periodontitis, implant diameter, implant design, implant location and bone augmentation are the risk factors of implant biological complications.