Keratinized mucosa changes around one-stage implants: A prospective case series

Abstract

Background: The need of an adequate band of keratinized tissue (KT) to maintain periodontal health around teeth as well as around implants has been a debated topic over many years but still no conclusions have been drawn. Objectives: This prospective case series evaluates the changes undergone by the keratinized mucosa (KM) and the soft tissue volume around non-submerged implants before the prosthetic rehabilitation. Material and Methods: A total of 40 patients were included. The primary outcome was to analyze the width of the KM at both buccal and lingual aspects compared to the pre-existing KT in the edentulous ridge only in mandibular (pre)molar area. The mucogingival line was marked with a surgical pen and an intra-oral scanner was used to take the impression of the implant area the day of the surgery (T0, baseline) and before the crown placement (T1, 3 months). Buccal soft tissue volume was measured at 1, 3, and 5 mm apical to the healing abutment position and a comparison between T0 and T1 was performed. Student t-test was used according to the distribution of the data (Shapiro–Wilk). Results: The mean KT width at baseline was 4.54 ± 1.31 mm at buccal side and 5.04 ± 1.88 mm at lingual side. After 3 months, the mean KM values were 3.15 ± 1.03 mm and 3.72 ± 1.56 mm at the buccal and lingual aspects, respectively. The differences, 30.6% of KM reduction buccally and 26.1% of reduction lingually, were statistically significant for both sides. Conclusions: Within the limitations of this investigation, it was observed that the KM width from the baseline to the 3 months follow up presented a significant dimensional change in both the buccal and lingual aspects, whereas buccal soft tissue volume showed an increase between baseline and follow up.