Randomized controlled clinical trial comparing implant sites augmented with a volume‐stable collagen matrix or an autogenous connective tissue graft: 3‐year data after insertion of reconstructions

Abstract

Aim:To assess mid-term clinical, radiographic and profilometric outcomes at implant sites, previously grafted with a volume-stable collagen matrix (VCMX) or an autogenous subepithelial connective tissue graft (SCTG).Methods: VCMX or SCTG were randomly applied to single implant sites in 20 patients. Following abutment connection and insertion of final reconstructions (baseline), patients were re-examined at 6 months (6M), at 1 year (FU-1) and at 3 years (FU-3). Measurements included the following: clinical data, radiographic measurement of first bone to implant contact (fBIC), soft tissue thickness and volumetric outcomes. Non-parametric tests and estimates were applied for the statistical analysis. Results:The median buccal mucosal thickness increased by 0.5 mm (Q1: -0.5; Q3: 1.25) (VCMX) (p = .281) and by 0.8 mm (Q1: 0.0; Q3: 2.5) (SCTG) (p = .047) between BL and FU-3 (intergroup p = .303). The profilometric changes of the buccal soft tissues demonstrated a median decrease between BL and FU-3 of −0.2 mm (Q1: −0.5; Q3: −0.1) (p = .039) for VCMX and a decrease of −0.1 mm (Q1: −0.8; Q3: 0.1) (p = .020) for SCTG, respectively (intergroup p = .596). Peri-implant soft tissues and bone levels remained healthy throughout the entire study period. PROMs did not show any significant differences between the groups nor significant changes over time.

How Thick Is the Oral Mucosa around Implants after Augmentation with Different Materials: A Systematic Review of the Effectiveness of Substitute Matrices in Comparison to Connective Tissue Grafts

“…Seven studies [ 16 , 17 , 18 , 19 , 20 , 21 , 22 ] fulfilled the inclusion criteria, two of those were classified as Follow-ups [ 17 , 19 ]. We identified 1050 potentially relevant studies through a systematic electronic database search (521 Ovid Medline + 529 WoS All Databases).…”

“…The study characteristics and the authors’ conclusions are presented in Table 1 . Different techniques were used to measure the thickness of oral mucosa: two authors measured with CAD/CAM (Computer Aided Design/Computer Aided Manufacturing) manufactured stents and endodontic needles [ 17 , 19 ], three just with endodontic needles [ 16 , 20 , 22 ], one with an ultrasonic device [ 18 ], and one with CBCT-scans with a small field of view [ 21 ] to ensure a high quality picture. The CAD/CAM-made stents had guide channels for the endodontic needles so that the measurements were particularly reproducible.…”

“…The surgical procedures are presented in Table 3 . The baseline was defined as the time of the first measurement before any augmentation took place, with the exception of the work of Huber et al and Thoma et al [ 20 , 22 ]. 2020, where the baseline was the insertion of the prosthetic crowns.…”

“…Over the course of 15 months, CTGs gained 0.4 mm for an average of 3.1 mm (SD ± 1.3), while the CM-Group lost 0.4 mm, resulting in a mean thickness of 2.8 mm (SD ± 0.7). Thoma et al [ 20 ] took another measurement after an additional 24 months, so three years after the restorations were inserted. Patient treated with CTGs showed a mean thickness of 3.8 mm (SD ± 1.5), while Thoma et al [ 20 ] reported 3.6 mm (SD ± 1.5) for the CM-Group.…”

A 3-Year Prospective Study on a Porcine-Derived Acellular Collagen Matrix to Re-Establish Convexity at the Buccal Aspect of Single Implants in the Molar Area: A Volumetric Analysis

“…Of this initial gain, 0.77 mm remained after 24 months pointing to a relative horizontal stability of 49%. Four RCTs from the same research group investigated soft tissue augmentation using Fibro-Gide ® (Geistlich Pharma AG, Wolhusen, Switzerland) [48][49][50][51]. Transmucosal probing revealed an initial gain of 1.7 mm with 35% shrinkage after three months and a horizontal stability of 41% three years after crown insertion.…”