Influence of keratinized mucosa on peri-implant diseases: a retrospective cohort study in humans

Objective The present study aimed to assess the relationship between keratinized mucosa width and peri-implant diseases, namely peri-implant mucositis and peri-implantitis. Materials and methods Ninety-one dental implants in function for ≥ 6 months from 40 partially or completely edentulous non-smoker subjects (24 females and 16 males) were evaluated clinically and radiographically. The width of keratinized mucosa, probing depth, plaque index, bleeding on probing, and marginal bone levels were assessed. Keratinized mucosa width was categorized as ≥ 2 mm or < 2 mm. Results There was no statistically significant association between keratinized buccal mucosa width and peri-implant mucositis or peri-implantitis (p ≥ 0.37). In the regression analysis, peri-implantitis was associated with longer implant function time (RR: 2.55, 95% CI: 1.25–11.81, p = 0.02) and implants in the maxilla (RR: 3.15, 95% CI: 1.61–14.93, p = 0.003). Mucositis was not associated with any of the factors analyzed. Conclusion In conclusion, in the present sample, keratinized buccal mucosa width was not associated with peri-implant diseases, suggesting that a band of keratinized mucosa may not be necessary to maintain peri-implant health. Prospective studies are required to better understand its role in the maintenance of peri-implant health.