Association of Keratinized Mucosa and Periimplant Soft Tissue Stability Around Implants with Platform Switching

Purpose: To investigate the influence of the width of keratinized mucosa (KM) on clinical parameters around dental implants with platform switching. Methods: One hundred eighteen patients with 320 implants participated in the evaluation. The width of KM, modified sulcus bleeding index (mBI), plaque index (PLI), mucosal recession (MR), and the compliance to the implant maintenance therapy (IMT) were evaluated. Results: A wide band of KM (KM width ≥ 2 mm) was associated with a significant lower mBI (0.12 ± 0.37; P < 0.0001), PLI (0.45 ± 0.56; P 0.001), and less MR (0.06 ± 0.23; P < 0.0001) than a narrow band of KM (KM width < 2 mm) (Papilla Bleeding Index [PBI], 0.39 ± 0.60; PLI, 0.69 ± 0.63; MR, 0.27 ± 0.44). By "regular" and "irregular" IMT, a statistically significant difference was found between wide and narrow width of KM, for the mBI (wide vs narrow; 0.11 ± 0.31 vs 0.31 ± 0.52, P 0.004 and 0.14 ± 0.45 vs 0.49 ± 0.69, P 0.002, respectively). Conclusion: Absence of keratinized mucosa was associated with significant higher PLI, mBI, and MR. The IMT does not reject the protective role of KM against inflammation.