NCT05211115

Autogenous vs. Xenogeneic Peri-implant Soft Tissue Grafts Placed in Full vs. Split Thickness Flaps

Randomised Clinical Trial Comparing Autogenous vs. Xenogeneic Peri-implant Soft Tissue Grafts Placed in Full vs. Split Thickness Flaps: a Clinical, Histological and Vascular Analysis

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 40 (actual)
• Sponsor: Universidad Complutense de Madrid · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

Randomized, outcome assessor and data analyst blinded, single center trial with four parallel arms and a 1:1:1:1 allocation ratio, with the aim of comparing which combination of bilaminar technique (split vs. full thickness flap) and graft type (autogenous or xenogeneic) provides better clinical, aesthetic, morphological, vascular and patients related outcomes, when augmenting the buccal peri-implant mucosa at the reopening of submerged implant fixtures

Detailed description

This randomized four parallel arms controlled clinical trial with blinded outcome assessment and data analysis aims to establish which combination of bilaminar technique (split vs. full thickness flap) and graft type (autogenous subepithelial connective tissue graft vs. volume stable collagen matrix) provides better clinical, aesthetic, morphological, vascular and patients related outcomes, when augmenting the buccal peri-implant mucosa at the reopening of submerged implant fixtures. The primary outcome is the gain in soft tissue thickness (standardised measurement at baseline, after surgery, at 1m and 6m). Secondary outcomes include changes in tissue volume (intraoral scans at baseline, post-op, 14d, 1m, 6m), RAL and KTW (clinical measurements at baseline, 1m, 6m), tissue color integration (∆E at 1m and 6m), and PROMS (7d, 14d, 30d). Exploratory outcomes include tissue morphology (histology at 1m,2m,4m,6m), microcirculation (Doppler flowmetry at pre-op, 7d, 14d, 1m) and revascularization (IHC at 1m,2m,4m,6m). A figure of 10 subjects per group was obtained for a 0,3mm difference in tissue thickness increase (SD 0,23mm), using 80% power, alpha 0.05, and a 10% drop-out rate. Patients will be randomly allocated to four groups: test (STF+VCM), control 1 (FTF+VCM), control 2 (SFT+CTG), control 3 (FTF+CTG). Patients will be the unit of analysis and ANOVA (normality) or Kruskall-Wallis (no normality) tests will be performed setting the significance level at p \< 0.05.

Conditions

• Thin Gingiva

Interventions

Type	Name	Description
PROCEDURE	Split thickness flap	Palatally displaced crestal incision at the edentulous site, combined with the split thickness elevation of a buccal flap, extended to the sulcus of the adjacent mesial and distal tooth. Flap elevation performed with a micro-blade, in a buccal and apical direction, for approximately 15mm apical to the crestal incision.
PROCEDURE	Full thickness flap	Palatally displaced crestal incision at the edentulous site, combined with the full thickness elevation of a buccal flap, extended to the sulcus of the adjacent mesial and distal tooth. Flap elevation performed with a fine periosteal elevator, in a buccal and apical direction, for approximately 15mm apical to the crestal incision.
PROCEDURE	Autogenous sub epithelial connective tissue graft	Harvest of a sub epithelial connective tissue graft using a double incision technique, approximately 2-3 mm apical to the palatal gingival margins of the first and second premolars. Graft dimension standardised as 10mm (mesio-distally) by 6-8mm (apico-coronally) by 1,5mm (thickness). Graft stabilised at the inner aspect of the buccal flap, 1mm apical to the flap margin, using one mesial and one distal horizontal mattress sutures.
PROCEDURE	Volume stable collagen matrix	Geistlich Fibro-Gide® matrix shaped at a standardised dimension of 10mm (mesio-distally) by 6-8mm (apico-coronally) by 6mm (thickness). Matrix stabilised at the inner aspect of the buccal flap, 1mm apical to the flap margin, using one mesial and one distal horizontal mattress sutures.

Timeline

• Start date: 2022-01-24
• Primary completion: 2023-12-15
• Completion: 2024-12-01
• First posted: 2022-01-27
• Last updated: 2024-12-19

Locations

1 site across 1 country: Spain