Efficacy of acellular dermal matrix and autogenous connective tissue grafts in the treatment of gingival recession defects among Asians

Comparison of the Characteristics of Three Acellular Dermal Matrices Subjected to Distinct Processing Methods Using Five Types of Histochemical Staining

BACKGROUND

Acellular dermal matrix (ADM) is treated using various devitalization and aseptic processing methods. The processing effects on ADM were evaluated by histochemical tests.

METHODS

From January 2014 to December 2016, 18 patients [average age, 43.0 (range, 30-54) years] who underwent breast reconstruction with an ADM and tissue expander were prospectively enrolled. During the permanent implant replacement, a biopsy of the ADM was performed. We used three different human-derived products, namely, Alloderm®, Allomend®, and Megaderm®. Hematoxylin and eosin, CD68, CD3, CD31, and smooth muscle actin were used to evaluate the collagen structure, inflammation, angiogenesis, and myofibroblast infiltration. Each ADM was semi-quantitatively analyzed.

RESULTS

Significant differences in collagen degradation, acute inflammation, and myofibroblast infiltration were observed among the ADMs. Collagen degeneration (p<0.001) and myofibroblast infiltration (smooth muscle actin-positive, p=0.018; CD31-negative, p=0.765) were the most severe in Megaderm®. Acute inflammation, represented by CD68, was most severe in Alloderm® (p=0.024). Both radiation and freeze-drying treatment physically damaged the collagen structure. Collagen degeneration was most severe in Megaderm®, followed by Allomend® and Alloderm®. Since Alloderm® is treated using chemicals, an assessment of the chemical irritation is warranted.

CONCLUSIONS

The biopsy results were inconclusive. Therefore, to better interpret processing, more large-scale, serial, histochemical studies of each ADM are needed.

LEVEL OF EVIDENCE IV

This journal requires that authors 38 assign a level of evidence to each article. For a full 39 description of these Evidence-Based Medicine ratings, 40 please refer to the Table of Contents or the online 41 Instructions to Authors www.springer.com/00266 .

The Progress of Decellularized Scaffold in Stomatology

The oral and maxillofacial region contains oral organs and facial soft tissues. Due to the complexity of the structures and functions of this region, the repair of related defects is complicated. Different degrees of defects require different repair methods, which involve a great combination of medicine and art, and the material requirements are extremely high. Hence, clinicians are plagued by contemporary oral repair materials due to the limitations of bone harvesting, immune rejection, low osteogenic activity and other problems. Decellularized extracellular matrix has attracted much attention as a bioactive scaffold material because of its nonimmunogenic properties, good osteogenic properties, slow release of growth factors, promotion of seed cell adhesion and maintenance of stem cell characteristics. This article reviews the sources, preparation methods, application and research progress of extracellular matrix materials in the repair of oral and maxillofacial defects to provide an overview for fundamental research and clinical development.

Clinical efficacy of xenogeneic and allogeneic 3D matrix in the management of gingival recession: a systematic review and meta-analysis

OBJECTIVE

A systematic review and meta-analysis was thus conducted to answer the following focused question based on PICO strategy: Is there any 3D matrix biomaterial used for root coverage of human Miller class I and II defects equivalent with the connective tissue graft in localized defects of at least 2 mm and 3 mm?

MATERIAL AND METHODS

The search on electronic database included MEDLINE, Cochrane Central Register of Controlled Trials, Clinical Trials.gov, Web of Science, and New Zealand/Australian Clinical Trials. Only randomized clinical trials (RCTs) that compared connective tissue graft (CTG) with at least one 3D matrix alone for root coverage in Class I and II Miller localized defects of at least 2 mm, with at least 6 months follow-up, were included in this systematic review.

RESULTS

A total of 14 studies were included for meta-analysis (12 compared CTG with acellular dermal matrix allograft and 2 compared CTG with Xenogenic Collagen Matrix). Relative root coverage showed no significant difference among the materials, for either 2 or 3 mm minimal recessions. For keratinized tissue width, on 2 mm recessions, CTG showed superiority above other biomaterials, but on 3 mm recessions, it seemed to have the same results. The percentage of recessions with complete root coverage for both 2 and 3 mm recessions showed similar results for all biomaterials.

CONCLUSIONS

With their limits, the present data concluded that CTG, acellular dermal matrix allograft, and xenogenic collagen matrix provided similar results for root coverage.

CLINICAL RELEVANCE

To know if there is a 3D matrix with equivalent predictable results for root coverage, that we could avoid the morbidity of the connective tissue graft for these cases.

Root coverage using coronally advanced flap with porcine-derived acellular dermal matrix or subepithelial connective tissue graft: a randomized controlled clinical trial

OBJECTIVE

The aim of this study is to investigate the use of a porcine-derived acellular dermal matrix (MD) in root coverage procedures combined with extended coronally positioned flap (eCAF), in comparison to the subepithelial connective tissue graft (SCTG) associated with the eCAF.

MATERIAL AND METHODS

Eighteen adult patients presenting bilateral type 1 gingival recession were randomly assigned to SCTG or MD groups. Clinical and patient-based outcomes were recorded at 3 and 6 months after the surgical procedure.

RESULTS

Both groups showed a significant reduction in the mean recession height of 3.33 ± 0.89 mm to 1.24 ± 1.10 mm (MD) and 3.21 ± 0.8 mm to 0.83 ± 0.86 mm (SCTG) without difference between groups. Six patients in the test group and eight in the control group obtained complete root coverage. The keratinized tissue height and thickness (KTT) showed a significant increase after 3 and 6 months in both groups. The average KTT gains were 0.39 ± 0.4 mm (MD) and 0.51 ± 0.5 mm (SCTG) (p < 0.05). Performing multivariate analysis suggests that MD addition to coronally advanced flaps may be similar to SCTG.

CONCLUSION

The MD had similar results in comparison to SCTG and in the context of reducing patient morbidity it can be used as an alternative for the treatment of gingival recessions.

CLINICAL RELEVANCE

The SCTG is the gold standard therapy for root coverage. The MD has been widely used in mucogingival surgery as a substitute for SCTG and proposed similar results. A substitute is very important for clinicians and patients. It will give a better postoperative and possibilities to treat multiples recession. (Clinicaltrials.gov Identifier: NCT03675334).

[Research progress on substitutes for autogenous soft tissue grafts in mucogingival surgery]

Mucogingival surgery is a general term for periodontal surgeries that correct aberrant periodontal soft tissues. Conventional mucogingival surgeries with pedicle flap or autologous soft tissue graft for treatment of gingival recession and insufficient keratinized tissues are always related to disadvantages such as need for a second surgery site, limited supplies, and complaints for postoperative discomfort. In this regard, research and application of soft tissue substitutes have gained increasing attention. Various kinds of soft tissue substitutes, including acellular dermal matrix and xenogeneic collagen matrix, have been developed and applied to clinical treatment. This review aims to summarize advances in research of the characteristics and clinical effectiveness of several soft tissue substitutes and provide references for clinical application.

Acellular dermal matrix and subepithelial connective tissue grafts for root coverage: A systematic review

BACKGROUND

The aim of this systematic review was to evaluate whether patients with gingival recession would benefit from an acellular dermal matrix graft (ADMG) in ways that are comparable to the gold standard of the subepithelial connective tissue graft (SCTG).

MATERIALS AND METHODS

A systematic review and meta-analysis comparing ADMG to SCTG for the treatment of Miller Class I and II recession defects was conducted according to PRISMA guidelines. PubMed, Excerpta Medica Database, and Cochrane Central Register of Controlled Trials databases were searched up to March 2016 for controlled trials with minimum 6 months duration. The primary outcome was root coverage; secondary outcomes included attachment level change, keratinized tissue (KT) change, and patient-based outcomes. Both authors independently assessed the quality of each included trial and extracted the relevant data.

RESULTS

From 158 potential titles, 17 controlled trials were included in the meta-analysis. There were no differences between ADMG and SCTG for mean root coverage, percent root coverage, and clinical attachment level gain. ADMG was statistically better than SCTG for gain in width of KT (-0.43 mm; 95% confidence interval: -0.72, -0.15). Only one study compared patient-based outcomes.

CONCLUSION

This review found that an ADMG would be a suitable root coverage substitute for an SCTG when avoidance of the second surgical site is preferred.