Residual Periodontal Pockets at Implant Placement as Risk Indicator for Peri-Implantitis: A Systematic Review

Intro The present systematic review aimed to assess whether the presence of residual periodontal pockets (PPD) after active periodontal therapy increases the risk of developing peri-implantitis in patients with treated periodontitis who undergo implant therapy. Methods An electronic search was performed in MEDLINE via PubMed, Scopus, Embase, and Cochrane Library. Studies including patients receiving at least one dental implant, in whom residual PPD or furcation involvement were recorded, were selected. The primary outcome was the incidence of peri-implantitis. Risk of bias was assessed using the Newcastle–Ottawa Scale. No meta-analysis could be performed due to heterogeneity across studies. Results From 3870 retrieved records, 4 cohort studies fulfilled the inclusion criteria, with follow-up ranging from 1 to 23 years. All included studies evaluated residual PPD as the exposure of interest, whereas no study specifically assessed furcation involvement. Despite substantial heterogeneity in exposure definitions and peri-implantitis case definitions, all studies consistently suggested that residual PPD persisting after active periodontal therapy was associated with increased peri-implantitis occurrence. In particular, deeper PPD (≥ 5 or ≥ 6 mm) and higher proportions of residual diseased sites were associated with greater peri-implantitis risk. One study additionally reported that inflammatory periodontal conditions affecting adjacent teeth increased peri-implantitis risk. Most studies were judged to be at moderate risk of bias. Conclusion Residual PPD persisting after active periodontal therapy can increase the risk of peri-implantitis in treated periodontitis patients receiving dental implants. Prospective studies adopting standardized case definitions of peri-implantitis are needed to further clarify the influence of residual PPDs and furcation involvement on implant outcomes. Trial Registration: PROSPERO: CRD42024567630