Impact of Keratinized Mucosa Width and Mucosal Thickness on Implant Outcomes and Brushing Discomfort: A 25‐Year Cohort Study
Emilio Couso‐Queiruga, Clemens Raabe, Andrea Roccuzzo, Giovanni E. Salvi, Manrique Fonseca, Vivianne ChappuisABSTRACT
Objective
To assess the impact of keratinized mucosa width (KMW) and mucosal thickness (MT) on peri‐implant conditions over 25 years in patients with adequate oral hygiene enrolled in regular supportive peri‐implant care.
Methods
Partially edentulous patients rehabilitated with tissue‐level implants were clinically and radiographically evaluated by calibrated examiners. Patient‐reported brushing discomfort was recorded, and associations with variables of interest were analysed.
Results
A total of 149 patients, 235 implants, with a mean follow‐up of 25.4 ± 3 years, were included. Peri‐implantitis prevalence was 11.1%, 0% and 7.1% in the 0‐mm, < 2‐mm and ≥ 2‐mm KMW groups, respectively ( p = 0.98). Sites with 0 mm KMW showed significantly greater crestal bone loss (CBL) than < 2 mm (−0.28 mm) and ≥ 2 mm (−0.40 mm) ( p = 0.01). Absence of KMW was associated with an increased risk of peri‐implant soft‐tissue dehiscence (PSTD) and implant platform visibility ( p ≤ 0.01). No significant differences were observed for probing depth (PD), bleeding on probing (BOP), plaque index or peri‐implant diseases ( p > 0.05). MT was not associated with CBL, PD, BOP, suppuration on probing (SOP) or peri‐implant diseases ( p > 0.05). Thin MT (< 2 mm) was linked to increased PSTD ( p = 0.005), greater implant platform visibility ( p = 0.04) and lower plaque index ( p = 0.01). Brushing discomfort was reported in 11.4% of sites with 0 mm KMW, compared with 3.4% and 2.4% in the < 2 mm and ≥ 2 mm groups, respectively, with no significant associations across KMW or MT groups ( p > 0.05).
Conclusions
KMW was associated with long‐term peri‐implant tissue stability, whereas thin MT was primarily associated with an increased risk of PSTD. Neither KMW nor MT was significantly associated with long‐term brushing discomfort.