The amount of keratinized mucosa may not influence peri-implant health in compliant patients: A retrospective 5-year analysis

Aim (a) To investigate the influence of the keratinized mucosa (KM) on peri-implant health or disease and (b) to identify a threshold value for the width of KM for peri-implant health. Materials and Methods The total dataset was subsampled, that is one implant was randomly chosen per patient. In 87 patients, data were extracted at baseline (prosthesis insertion) and 5 years including the width of mid-buccal KM, bleeding on probing, probing depth, plaque index and marginal bone level (MB). Spearman correlations with Holm adjustment for multiple testing were used for potential associations. Results Depending on the definition of peri-implant diseases, the prevalence of peri-implantitis ranged from 9.2% (bleeding on probing threshold: <50% or >= 50%) to 24.1% (threshold: absence or the presence). The prevalence of peri-implant mucositis was similar, irrespective of the definition (54%-55.2%). The width of KM and parameters for peri-implant diseases demonstrated negligible (Spearman correlation coefficients: -0.2 rho < 0.2). No threshold value was detected for the width of mid-buccal KM in relation to peri-implant health. Conclusion The width of KM around dental implants correlated to a negligible extent with parameters for peri-implant diseases. No threshold value for the width of KM to maintain peri-implant health could be identified.