The role of keratinized mucosa width as a risk factor for peri‐implant disease: A systematic review, meta‐analysis, and trial sequential analysis

Background Studies have examined the benefit of having keratinized peri‐implant mucosa width with mixed results. Purpose This study examines whether the lack of a prespecified (2 mm) amount of keratinized mucosa width (KMW) is a risk factor for peri‐implant diseases. Methods A systematic electronic and manual search of randomized or nonrandomized controlled or noncontrolled clinical trials was conducted. Qualitative review, quantitative meta‐analysis, and trial sequence analysis (TSA) of implants inserted at sites with 0.05) and a low power of evidence were found for probing depth, soft‐tissue recession, and marginal bone loss. A significant difference favoring ≥2 mm KMW had a lower mean plaque index (MD = 0.37, 95% CI: [0.16, 0.58], p = 0.002) (3 studies, 430 implants, low‐quality evidence). GRADE system showed very low and low quality of evidence for all other outcome measures. Conclusion Based on the available studies, the impact of amount of KMW (either