Peri-implant mucosal enhancement using leukocyte platelet rich fibrin under Sohn's poncho technique: A randomized controlled clinical trial.

Background: A biological seal that protects the implant from any biological or external impingement is created by the supracrestal attached tissues. Sohn's poncho technique is a technique that utilizes a healing abutment at the implant site to stabilize the platelet rich fibrin (PRF) membrane. Thus, the aim of this study is to evaluate the efficacy of Sohn's poncho technique used for placement of leukocyte PRF (L-PRF) membrane in improving the peri-implant mucosal thickness and width of keratinized mucosa as well as in the acceleration of healing process compared to the peri-implant mucosa surrounding healing abutments placed without the L-PRF membrane.

Methods: A split mouth randomized controlled clinical trial was designed in which implants were placed in the mandibular posterior region. Healing abutment is placed along with the L-PRF membrane at the test site using Sohn's poncho technique and at control site conventional healing abutment placement was done at second stage. The thickness of peri-implant mucosa as primary outcome and the Width of keratinized tissue and healing as secondary outcomes were measured and assessed at various time intervals.

Results: Statistically significant difference was seen in inter-group analysis when peri-implant mucosal thickness (3.8 ± 0.4 mm vs. 2.3 ± 0.4 mm) and width of keratinized mucosa (3.6 ± 0.6 mm vs. 2.7 ± 0.3 mm) in test and control groups respectively and intragroup analysis of test and control groups at 4 weeks and 6 weeks' time points. The control group showed faster healing when compared to the test group.

Conclusion: Sohn's poncho technique in combination with L-PRF has the potential to improve the thickness of peri-implant mucosa and the width of keratinized mucosa around implants.