Autogenous Subepithelial Connective Tissue Graft Research Articles

Comparative analysis of xenogeneic collagen matrix and autogenous subepithelial connective tissue graft to increase soft tissue volume around dental implants: a systematic review and meta-analysis

ObjectiveThe gold standard for a soft tissue augmentation around implants is a subepithelial connective tissue graft (CTG), but the xenogeneic collagen matrices (XCM) started to be used as an alternative. This systematic review aimed to assess the effectiveness XCM in comparison to CTG for the increasing the thickness of the soft tissue around implants.DataAll studies included at least two parallel groups comparing the use of CTG and XCM with a minimum follow-up of 3 months. As the primary outcome, the amount of soft tissue thickness gain after soft tissue augmentation with XCM or CTG was assessed. Secondary outcomes were clinical and patient-related outcomes; evaluation of aesthetic outcomes, patient-reported outcomes measures (PROMs) and complications. Eligible studies were selected based on the inclusion criteria. Meta-analysis was applied whenever possible. The quality of the evidence of studies including in meta-analysis was assessed using the GRADE approach.SourceA systematic literature search up to January 2022 was conducted using the following electronic databases: PubMed (MEDLINE), Scopus, Cochrane Library, LILACS, eLIBRARY.RU. Unpublished researches, the gray literature, nonprofit reports, government studies and other materials were reviewed electronically using an EASY search. An additional manual search was carried out in November 2022.Study selectionOf the 1376 articles from the initial search, 8 randomized controlled trials (RCTs) (306 patients and 325 implants) were included in this systematic review, and 7 studies were part of the meta-analysis. Meta-analysis revealed that XCM is less effective than the CTG in increasing soft tissue thickness around dental implants. However, XCM also provides soft tissue thickness gain and can be recommended for use in various clinical situations.Clinical significancePrevious systematic reviews and meta-analyses have shown that autologous grafts are more effective than collagen matrices in increasing soft tissue thickness, however, the latter can be used as an alternative. Studies included in previous systematic reviews varied in design, which could lead to limitations. The present systematic review and meta-analysis includes for the first time only randomized controlled clinical trials with collagen matrix of xenogeneic origin in the test group. Tight eligibility criteria were established, and the main parameter studied was soft tissue thickness. It was found that xenogeneic collagen matrix is effective for increasing soft tissue thickness around dental implants, however, the results obtained using an autogenous connective tissue graft are superior.

Gingival biotype modification with collagen matrix or autogenous subepithelial connective tissue graft: Histologic and volumetric analyses in a beagle model

ObjectivesTo evaluate the volumetric effect and biocompatibility of porcine tendon-derived type I collagen matrix graft (CG) in gingival biotype modification (GBM) compared with subepithelial connective tissue graft (SCTG) in a beagle model. MethodsSurface analysis using scanning electron microscopy and a collagen degradation assay of CG was performed in vitro. Six adult dogs were used in in vivo experiment, and each received autologous SCTG or CG at the anterior side. Histometric and three-dimensional digital volume analyses were conducted to compare quantitative changes in CG and SCTG in GBM. Immunohistochemical analysis was performed for the qualitative evaluation of CG compared to SCTG. ResultsCG had a double-layered structure, and its degradation was slower than that of other well-reported materials. No critical problems were associated with the healing procedure. Changes in gingival thickness and volume in the CG and SCTG groups were equivalent, with no significant differences between the groups. Type I collagen and vascular endothelial growth factor expression levels were similar in both groups. SignificanceCG and SCTG had equivalent potential for GBM in terms of quantity and quality. Additionally, CG could be used as a reasonable substitute for SCTG, making surgery convenient and predicting successful clinical outcomes.

Treatment of Multiple Gingival Recessions Using Modified Tunnel Technique with V-reverse Sutures: A Report of Three Cases

The clinical case series presents a minimally invasive modified tunnel procedure with autogenous connective tissue graft (CTG) using a V-reverse sutures to treat multiple gingival recessions. In periodontal and peri-implant plastic procedures, proper graft and flap stabilization are crucial in the outcomes. The coronally advanced flap allows for better access with the possibility of suturing the graft to the de-epithelialized papillae of the periosteum; there is little evidence with using the V-reverse sutures technique in stabilizing the graft and the flap when performing tunnel techniques (TUN). The following case series presents a minimally invasive modified tunnel procedure with autogenous CTG using V-reverse sutures to treat gingival recessions. Three patients with Miller Class I maxillary buccal gingival recessions defects were selected for this study. All subjects were treated with the minimally invasive modified tunnel technique with autogenous subepithelial CTG. V-reverse sutures technique was performed to further improve the stability of the graft at the recipient site. Clinical parameters, including mean recession depth and root coverage esthetic score (RES), were recorded at baseline, 1 week, 2 weeks, 1 month, 3 months, 6 months, and 1-year postoperative follow-up visits. At the 1-year follow-up, complete root coverage was achieved in multiple gingival recessions defect sites. In conclusion, this technique represents an alternative treatment for Miller Class I gingival recessions defects with clinical and esthetically satisfactory outcomes. Combining the advantages of V-reverse sutures and CTG in the treatment of gingival recessions is feasible and noninvasive.

Does the subepithelial connective tissue graft in conjunction with a coronally advanced flap remain as the gold standard therapy for the treatment of single gingival recession defects? A systematic review and network meta-analysis.

The aim of this systematic review and network meta-analysis (NMA) was to assess the efficacy of a bilaminar root coverage technique consisting of the combination of an autogenous subepithelial connective tissue graft (SCTG) and a coronally advanced flap (CAF) compared with the five most indicated alternative approaches for the treatment of single gingival recession defects (GRD). The protocol of this PRISMA 2020-compliant systematic review was registered in PROSPERO (CRD42020221362). Three electronic databases were searched up to September 30, 2021 to identify randomized controlled trials that involved the treatment of single GRD without interproximal tissue loss via root coverage procedures. A frequentist NMA was conducted for complete root coverage (CRC), mean root coverage (MRC), and keratinized tissue width (KTW) changes. A total of 38 studies reporting on 830 patients and 1,265 GRD were included. SCTG + CAF was ranked as the most efficient treatment approach for MRC, CRC, and KTW gain at 6 and 12 months after surgery, except for MRC at the 12-month follow-up where enamel matrix derivative plus CAF exhibited superior results. SCTG + CAF can be considered the gold standard for the treatment of single GRD.

A split mouth clinical study to compare Subepithelial connective tissue graft and Guided tissue regeneration in the treatment of Miller’s class I and II gingival recession.

ABSTRACT 
 Background: Gingival recession (GR) can result in hypersensitivity, esthetic concern to the patient, and chances for root caries. The purpose of this randomized clinical study was to evaluate the effect of guided tissue regeneration (GTR) procedure using a bioabsorbable collagen membrane in comparison to autogenous Subepithelial connective tissue graft (SCTG) for root coverage in Miller’s class I and II gingival recession defects.
 Materials and methods: In this split mouth study, 10 patients with 20 contralateral Miller’s class I or II recession defects were randomly treated with coronally advanced flap using either Subepithelial connective tissue graft (control group) or resorbable collagen membrane (experimental group). The clinical evaluations were done using plaque index, gingival index, height of gingival recession, probing sulcus depth and clinical attachment level at baseline, 3 and 6 months post- operatively.
 Results: Data analysis was done using descriptive statistics and student’s t test was used for comparisons. P value <0.01 was considered to be significant. Both the groups showed complete resolution of the defects at 6 months post operatively. Inter group comparison between both the groups at 6 months showed no statistically significant differences in any of the clinical parameters.
 Conclusion: Predictable outcome were observed in both the groups and indicated that collagen based guided tissue regeneration membrane i.e. ProGide can be safely used.

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

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). 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 6months (6M), at 1year (FU-1) and at 3years (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. 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 -0.2mm (Q1: -0.5; Q3: -0.1) (p=.039) for VCMX and a decrease of -0.1mm (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. Minimal changes of the peri-implant tissue contour as well as of the soft tissue thickness were observed at implant sites previously grafted with VCMX or SCTG.

The Healing of Soft Tissue Augmentation by Acellular Dermal Matrix and Autogenous Subepithelial Connective Tissue Graft

The Healing of Soft Tissue Augmentation by Acellular Dermal Matrix and Autogenous Subepithelial Connective Tissue Graft

Non-interventional 1-year follow-up study of peri-implant soft tissues following previous soft tissue augmentation and crown insertion in single-tooth gaps.

To assess peri-implant soft tissue dimensions at implant sites, previously augmented with a collagen matrix (VCMX) or an autogenous subepithelial connective tissue graft (SCTG), between crown insertion and 1year. Twenty patients with single-tooth implants received soft tissue augmentation prior to abutment connection randomly using VCMX or SCTG. Following abutment connection 3 months later, final reconstructions were fabricated and inserted (baseline). Patients were recalled at 6 months (6M) and at 1 year (FU-1). Measurements included clinical data, soft tissue thickness, volumetric outcomes and patient-reported outcome measures (PROMs). The buccal soft tissue thickness showed a median decrease of -0.5mm (-1.0;0.3) (VCMX) and 0.0mm (-0.5;1.0) (SCTG) (p=.243) up to FU-1. The soft tissue volume demonstrated a median decrease between BL and FU-1 of -0.1mm (-0.2;0.0) (p=.301) for VCMX and a significant decrease of -0.2mm (-0.4; -0.1) (p=.002) for SCTG, respectively. Intergroup comparisons did not reveal any significant differences between the groups for peri-implant soft tissue dimensions and changes up to FU-1 (p>.05). PROMs did not show any significant changes over time nor differences between the groups. Between crown insertion and 1 year, the buccal peri-implant soft tissue dimensions remained stable without relevant differences between sites that had previously been grafted with VCMX or SCTG.

Volumetric and linear changes at dental implants following grafting with volume-stable three-dimensional collagen matrices or autogenous connective tissue grafts: 6-month data.

The objective of this study was to test whether or not soft tissue augmentation with a volume-stable collagen matrix (VCMX) leads to similar volume gain around dental implants compared to autogenous subepithelial connective tissue graft (SCTG). In 12 adult beagle dogs, immediate implants were placed with simultaneous guided bone regeneration. After 25-45weeks, soft tissue augmentation was randomly performed using VCMX, SCTG, or a sham-operated control. Impressions were taken pre-op and post-op (tissue augmentation) and again at sacrifice after healing periods of 4, 8, and 24weeks. They were then digitized to allow for superimposition. Values of linear and volumetric changes were calculated. The median increase (pre-op to post-op) in buccal volume measured 0.92mm for VCMX, 1.47mm for SCTG, and 0.24mm for SH. The values (pre-op to sacrifice) were -0.25mm for VCMX, 0.52mm for SCTG, and -0.06mm for group SH. The median ridge width 2mm below the crest measured -0.26mm for VCMX, 0.53mm for SCTG, and -0.15mm for SH (pre-op to sacrifice). Volume augmentation using VCMX and SCTG resulted in an increase in ridge dimension (pre- to post-op). During the follow-up, the volume decreased in all three groups to a level close to the situation prior to surgery. Soft tissue volume augmentation around dental implants is usually performed using the patient's own tissue. This therapy is associated with an increased morbidity due to a second surgical site. Soft tissue volume at implant sites can be augmented using VCMX and SCTG. The gain on top of the ridge appears not to be stable during the follow-up in both groups.

Soft tissue volume augmentation by the use of collagen‐based matrices in the dog mandible – a histological analysis

The aim was to test, whether or not soft tissue volume augmentation with a specifically designed collagen matrix (CM), leads to ridge width gain in chronic ridge defects similar to those obtained by an autogenous subepithelial connective tissue graft (SCTG). In six dogs, soft tissue volume augmentation was performed by randomly allocating three treatment modalities to chronic ridge defects [CM, SCTG and sham-operated control (Control)]. Dogs were sacrificed at 28 (n=3) and 84days (n=3). Descriptive histology and histomorphometric measurements were performed on non-decalcified sections. SCTG and CM demonstrated favourable tissue integration, and subsequent re-modelling over 84days. The overall mean amount of newly formed soft tissue (NMT) plus bone (NB) amounted to 3.8±1.2mm (Control), 6.4±0.9mm (CM) and 7.2±1.2mm (SCTG) at 28days. At 84days, the mean NMT plus NB reached 2.4±0.9mm (Control), 5.6±1.5mm (CM) and 6.0±2.1mm (SCTG). Statistically significant differences were observed between CM/SCTG and Control at both time-points (p<0.05). Within the limits of this animal model, the CM performed similar to the SCTG, based on histomorphometric outcomes combining NB and NMT.

Comparative evaluation of a bioabsorbable collagen membrane and connective tissue graft in the treatment of localized gingival recession: A clinical study.

Background:Gingival recession (GR) can result in root sensitivity, esthetic concern to the patient, and predilection to root caries. The purpose of this randomized clinical study was to evaluate (1) the effect of guided tissue regeneration (GTR) procedure using a bioabsorbable collagen membrane, in comparison to autogenous subepithelial connective tissue graft (SCTG) for root coverage in localized gingival recession defects; and (2) the change in width of keratinized gingiva following these two procedures.Materials and Methods:A total of 10 cases, showing at least two localized Miller's Class I or Class II gingival recession, participated in this study. In a split mouth design, the pairs of defects were randomly assigned for treatment with either SCTG (SCTG Group) or GTR-based collagen membrane (GTRC Group). Both the grafts were covered with coronally advanced flap. Recession depth (RD), recession width (RW), width of keratinized gingiva (KG), probing depth (PD), relative attachment level (RAL), plaque index (PI), and gingival index (GI) were recorded at baseline, 3 and 6 months postoperatively.Results:Six months following root coverage procedures, the mean root coverage was found to be 84.84% ± 16.81% and 84.0% ± 15.19% in SCTG Group and GTRC Group, respectively. The mean keratinized gingival width increase was 1.50 ± 0.70 mm and 2.30 ± 0.67 mm in the SCTG and GTRC group, respectively, which was not statistically significant.Conclusion:It may be concluded that resorbable collagen membrane can be a reliable alternative to autogenous connective tissue graft in the treatment of gingival recession.

Soft tissue volume augmentation by the use of collagen‐based matrices: a volumetric analysis

The aim was to test whether or not soft tissue augmentation with a newly developed collagen matrix (CM) leads to volume gain in chronic ridge defects similar to those obtained by an autogenous subepithelial connective tissue graft (SCTG). In six dogs, soft tissue volume augmentation was performed by randomly allocating three treatment modalities to chronic ridge defects (CM, SCTG, sham-operated control). Impressions were taken before augmentation (baseline), at 28, and 84 days. The obtained casts were optically scanned and the images were digitally analysed. A defined region of interest was measured in all sites and the volume differences between the time points were calculated. The mean volume differences per area between baseline and 28 days amounted to a gain of 1.6 mm (CM; SD+/-0.9), 1.5 mm (SCTG; +/-0.1), and a loss of 0.003 mm (control; +/-0.3). At 84 days, the mean volume differences per area to baseline measured a gain of 1.4 mm (CM; +/-1.1), 1.4 mm (SCTG; +/-0.4), and a loss of 0.3 mm (control; +/-0.3). The differences between CM and SCTG were statistically significant compared with control at 28 and 84 days (p<0.001). Within the limits of this animal study, the CM may serve as a replacement for autogenous connective tissue.

New Surgical Approach for Root Coverage of Localized Gingival Recession with Acellular Dermal Matrix: A 12-Month Comparative Clinical Study

Acellular dermal matrix graft (ADMG) has been used as an advantageous substitute for autogenous subepithelial connective tissue graft (SCTG). However, the surgical techniques used were primarily developed for the SCTG, and they may not be adequate for ADMG since it has a different healing process than SCTG owing to its different vascular and cellular structures. This study compared the 1-year clinical outcome of a new surgical approach with the outcome of a conventional procedure for the treatment of localized gingival recessions, both performed using the ADMG. The clinical parameters-probing depth, relative clinical attachment level, gingival recession (GR), and width of keratinized tissue-of 32 bilateral Miller Class I or II gingival recessions were assessed at baseline and 12 months postoperatively. Significant clinical changes for both surgical techniques were achieved after this period, including GR reduction from 3.4 mm presurgery to 1.2 mm at 1 year for the conventional technique and from 3.9 mm presurgery to 0.7 mm at 1 year for the new technique. The percentage of root coverage was 62.3% and 82.5% for the conventional and new techniques, respectively. Comparisons between the groups after this period by Mann-Whitney rank sum test revealed statistically significant greater reduction of GR favoring the new procedure (p = .000). Based on the results of this study, it can be concluded that a new surgical technique using an ADMG is more suitable for root coverage when compared with the conventional technique. The results revealed a statistically significant improvement in clinical performance with the ADMG approach.