The Role of the Keratinized Mucosa in Peri-Implant Diseases Onset and Brushing Discomfort: A 10-Year Follow-Up.

To evaluate the effect of narrow (< 2 mm) and wide (≥ 2 mm) keratinized mucosa (KM) over 10 years on peri-implant diagnosis and brushing discomfort. Eighty patients were initially evaluated. Demographic data, modified plaque index (mPI)/plaque index (PI), probing depth (PD), clinical attachment level (CAL), mucosal recession (REC), bleeding on probing (BoP), marginal bone level (MBL), brushing discomfort (BD), and peri-implant diagnosis were assessed. Implants were then divided into two groups according to the width of KM (narrow group: NG < 2 mm and wide group: WG ≥ 2 mm). Patients who returned after 4 years (T4) were invited to participate in the 10-year reassessment (T10). The same parameters were reassessed, and statistical analysis was performed. Thirty patients and 116 implants were included in this 10-year follow-up study. Although at T10 the prevalence of peri-implant diseases was not influenced by the KM width, the implants in the WG had 84% lower odds of being diagnosed with peri-implant diseases compared to those in the NG. Furthermore, the NG had higher PI, mPI, BoP, and REC than the WG. In addition, significant MBL was observed in the NG over 10 years. Both groups reduced BD, with no significant difference between them. A narrow KM favors plaque accumulation, mucosal recession, and peri-implant tissue inflammation in the long term, while a wider KM (≥ 2 mm) appears protective against peri-implant disease onset. Brushing discomfort declined over time irrespective of KM width.