Impact of implant location on the prevalence of peri-implantitis: A systematic review and meta- analysis

Objectives:To evaluate scientific evidence about the impact of implant location on the prevalence of peri-implantitis at implant level. Source:Databases (PubMed, Embase and Cochrane) were searched until March 2020without limitations on language or publication year. Hand searches and gray literature were also included. Study selection: Clinical studies reporting data on prevalence of peri-implantitis in anterior and posterior regions at implant level, and evaluations of implants with at least 1 year of function were selected. Data:Ten studies with a low risk of bias were included. Meta-analysis was performed to estimate the pooled risk ratio. A significantly higher prevalence of peri-implantitis in anterior region compared to posterior region was found (Risk ratio: 1.34; 95 % CI: [1.07, 1.69]; p = 0.01). Meta-regression was performed to analyze the potential influence of confounding factors by calculating p-value of the coefficient. Subjects (p = 0.827), implants (p = 0.859) and age (p = 0.656) did not significantly influence the outcome. Subgroup analysis by jaw revealed significantly higher prevalence of peri-implantitis in maxillary anterior (Risk ratio: 1.37; 95 % CI: [1.10, 1.71]; p = 0.005) and mandibular anterior (Risk ratio: 1.76; 95 % CI: [1.29, 2.42]; p = 0.0004) regions compared to maxillary posterior region. No significant difference was found between maxillary anterior and mandibular posterior (Risk ratio: 1.15; 95 % CI: [0.75, 1.75]; p = 0.53) regions. A meta-analysis was precluded between mandibular anterior and mandibular posterior regions due to high statistical heterogeneity (I 2 = 76 %). Conclusions:Implants in the maxillary anterior and mandibular anterior regions had a higher prevalence of peri-implantitis compared to the maxillary posterior region. Clinical significance: Practitioners should strictly grasp the indications for patients missing anterior teeth and make comprehensive treatment planning.