Comparative long-term study between two dermal regeneration templates for the reconstruction of burn scar contractures in humans: Clinical and histological results

Dermal Regeneration Template in the Management and Reconstruction of Burn Injuries and Complex Wounds: A Review

Background

Dermal scaffolds have created a paradigm shift for burn and wound management by providing improved healing and less scarring, while improving cosmesis and functionality. Dermal regeneration template (DRT) is a bilayer membrane for dermal regeneration developed by Yannas and Burke in the 1980s. The aim of this review is to summarize clinical evidence for dermal scaffolds focusing on DRT for the management and reconstruction of burn injuries and complex wounds.

Methods

A comprehensive search of PubMed was performed from the start of indexing through November 2022. Articles reporting on DRT use in patients with burns, limb salvage, and wound reconstruction were included with focus on high-level clinical evidence.

Results

DRT has become an established alternative option for the treatment of full-thickness and deep partial-thickness burns, with improved outcomes in areas where cosmesis and functionality are important. In the management of diabetic foot ulcers, use of DRT is associated with high rates of complete wound healing with a low risk of adverse outcomes. DRT has been successfully used in traumatic and surgical wounds, showing particular benefit in deep wounds and in the reconstruction of numerous anatomical sites.

Conclusions

Considerable clinical experience has accrued with the use of DRT beyond its original application for thermal injury. A growing body of evidence from clinical studies reports the successful use of DRT to improve clinical outcomes and quality of life across clinical indications at a number of anatomical sites.

Use of a collagen-elastin matrix with split-thickness skin graft for defect coverage in complex wounds

OBJECTIVE

Severe soft tissue damage with destruction of the dermis requires plastic reconstructive treatment. For multimorbid patients or patients unable to undergo major reconstructive surgery, use of dermal substitutes, such as a collagen-elastin matrix (CEM) with a split-thickness skin graft (STSG), instead of local or free flap surgery, may be a valid and easy treatment option. We aimed to investigate and compare the outcomes and rate of successful defect reconstruction using CEM plus STSG, using either a one-step approach (simultaneous CEM and STSG) or a two-step approach (CEM and negative wound pressure therapy (NPWT), with secondary STSG transplantation).

METHOD

A single-centre, retrospective follow-up study of patients who had received CEM was conducted. Wounds had been treated with an STSG transplantation covering a CEM (MatriDerm, MedSkin Solutions Dr. Suwelack AG, Germany). Previous attempts at wound closure with conventional methods had failed in the selected patient population, which would usually have resulted in flap surgery.

RESULTS

Overall, 46 patients were included (mean age 60.9±20.0 years), with a total of 49 wound sites. We analysed 38 patients with wounds that did not require flap coverage; 18 patients received the one-step approach and 20 patients received the two-step approach. The mean follow-up in these patients was 22±11.5 months, and one patient was lost to follow-up. Overall, 29 (78.4%) wounds remained closed. Wounds which did not successfully heal were related to comorbidities, such as diabetes, alcohol misuse and smoking. Using the one-step approach, long-term defect coverage was achieved in 13 (76.5%) wounds and 16 (80.0%) wounds were closed using the two-step approach. However, there was no statistically significant differences between the one- or two-step approaches regarding the rate of development of a wound healing disorder.

CONCLUSION

Wound closure was achieved in 38 complex wounds using CEM plus STSG, while 11 wounds needed secondary flap coverage. In the flap-free wounds, there were no statistically significant differences between the one-step versus two-step approach. Using a simple defect reconstruction algorithm, we successfully used CEM plus STSG to treat complex wounds.

Integra® Dermal Regeneration Template: From Design to Clinical Use

Integra^® Dermal Regeneration Template (IDRT, Integra LifeSciences, Princeton, NJ, USA) is a bilayer membrane developed, by Yannas and Burke in the 1980s, to fulfill the unmet need of surgeons having a readily available off-the-shelf dermal regeneration method. IDRT is composed of a sheet of porous cross-linked type I collagen and glycosaminoglycans, with a semi-permeable silicone sheet cover. IDRT is bio-engineered, from adult bovine Achilles tendons and chondroitin-6-sulfate derived from shark cartilage, in a multi-step process involving cross-linking using glutaraldehyde. By design, the composition, porosity, and biodegradation rate of IDRT guides the mechanism of wound repair towards a regenerative pathway. Its mechanism of action involves four distinct phases: imbibition, fibroblast migration, neovascularization, and remodeling/maturation. Originally developed for the post-excisional treatment of deep-partial to full-thickness burns where autograft is limited, over the years its use has expanded to reconstructive surgery.

A Biomimetic, Bilayered Antimicrobial Collagen-Based Scaffold for Enhanced Healing of Complex Wound Conditions

Chronic, nonhealing wounds in the form of diabetic foot ulcers (DFUs) are a major complication for diabetic patients. The inability of a DFU to heal appropriately leads to an open wound with a high risk of infection. Current standards of care fail to fully address either the underlying defective wound repair mechanism or the risk of microbial infection. Thus, it is clear that novel approaches are needed. One such approach is the use of multifunctional biomaterials as platforms to direct and promote wound healing. In this study, a biomimetic, bilayered antimicrobial collagen-based scaffold was developed to deal with the etiology of DFUs. An epidermal, antimicrobial collagen/chitosan film for the prevention of wound infection was combined with a dermal collagen-glycosaminoglycan scaffold, which serves to support angiogenesis in the wound environment and ultimately accelerate wound healing. Biophysical and biological characterization identified an 1-ethyl-3-(3-(dimethylamino)propyl)carbodiimide cross-linked bilayered scaffold to have the highest structural stability with similar mechanical properties to products on the market, exhibiting a similar structure to native skin, successfully inhibiting the growth and infiltration of Staphylococcus aureus and supporting the proliferation of epidermal cells on its surface. This bilayered scaffold also demonstrated the ability to support the proliferation of key cell types involved in vascularization, namely, induced pluripotent stem cell derived endothelial cells and supporting stromal cells, with early signs of organization of these cells into vascular structures, showing great promise for the promotion of angiogenesis. Taken together, the results indicate that the bilayered scaffold is an excellent candidate for enhancement of diabetic wound healing by preventing wound infection and supporting angiogenesis.

Comparing the application of various engineered xenografts for skin defects: A systematic review

INTRODUCTION

Xenografts are a now a cornerstone in the management of wound dressings. Promising results were achieved since 1960 in the application of skin substitute for skin defects.

OBJECTIVE

The objective of this study was to evaluate the efficacy of various xenografts.

METHODS

A literature research was conducted using the following query: 'Porcine skin dermatology substitute', 'bovine skin dermatology substitute', 'xenograft skin substitute dermatology', 'xenografts skin defect', 'porcine skin defect', 'bovine skin defect'.

RESULTS

The review yielded 35 articles pertaining to the topic. Main indications for porcine and bovine xenograft application were burn wounds and post-traumatic wounds, respectively. Mean discharge date or length of stay was at the 6th day after porcine application, and the time of graft healing was reported for 33.7% (n = 510) of patients. Promising results were seen with Matriderm and split-thickness skin graft. Most wounds achieved an excellent cosmetic result with full range of motion and a smooth contour appearance. A great variety of tissue substitutes exist, and the choice of graft application should depend on a patient's factors, product availability, wound type, size, and physician's factors.

CONCLUSION

In summary, xenografts are more economic and affordable but have higher risk of infections compared to allografts.

Wound Healing after Acellular Dermal Substitute Positioning in Dermato-Oncological Surgery: A Prospective Comparative Study

BACKGROUND

MatriDerm and Integra are both widely used collagenic acellular dermal matrices (ADMs) in the surgical setting, with similar characteristics in terms of healing time and clinical indication. The aim of the present study is to compare the two ADMs in terms of clinical and histological results in the setting of dermato-oncological surgery.

METHODS

Ten consecutive patients with medical indications to undergo surgical excision of skin cancers were treated with a 2-step procedure at our Dermatologic Surgery Unit. Immediately after tumor removal, both ADMs were positioned on the wound bed, one adjacent to the other. Closure through split-thickness skin grafting was performed after approximately 3 weeks. Conventional histology, immunostaining and ELISA assay were performed on cutaneous samples at different timepoints.

RESULTS

No significant differences were detected in terms of either final clinical outcomes or in extracellular matrix content of the neoformed dermis. However, Matriderm was observed to induce scar retraction more frequently. In contrast, Integra was shown to carry higher infectious risk and to be more slowly reabsorbed into the wound bed. Sometimes foreign body-like granulomatous reactions were also observed, especially in Integra samples.

CONCLUSIONS

Even in the presence of subtle differences between the ADMs, comparable global outcomes were demonstrated after dermato-oncological surgery.

A Risk-Benefit Review of Currently Used Dermal Substitutes for Burn Wounds

While split-thickness autologous skin grafts remain the most common method of definitive burn wound closure, dermal substitutes have emerged as an attractive option. There are many advantages of utilizing a dermal substitute, notably reducing the need for donor tissue and subsequent iatrogenic creation of a secondary wound. However, there are disadvantages with each that most be weighed and factored into the decision. And most come at a high initial financial cost. There is little comparative literature of the various available and emerging products. This analysis was performed to objectively present risks and benefits of each option.

Use of Dermal Regenerative Templates for Burns

Autologous skin grafting has permitted survival and restoration of function in burn injuries of ever larger total body surface area (TBSA) sizes. However, the goal of replacing "like with like" skin structures is often impossible because full-thickness donor harvesting requires primary closure at the donor site for it to heal. Split-thickness skin grafting (STSG), on the other hand, only harvests part of the dermis at the donor site, allowing it to re-epithelialize on its own. The development of the first dermal regenerative template (DRT) in the late 1970s represented a major advance in tissue engineering that addresses the issue of insufficient dermal replacement when STSGs are applied to the full-thickness defect. This review aims to provide an overview of currently available DRTs in burn management from a clinician's perspective. It focuses on the main strengths and pitfalls of each product and provides clinical pearls based on clinical experience and evidence.

Negative pressure wound therapy on complex extremity wounds requiring coverage with a meshed bilayer wound matrix: a retrospective analysis

OBJECTIVE

The treatment of complex extremity wounds is technically challenging. In this 5-year retrospective review, we compared the use of Integra Meshed Bilayer Wound Matrix (IMBWM; Integra LifeSciences, US) followed by a split-thickness skin graft (STSG) combined with negative pressure wound therapy (NPWT) versus IMBWM followed by STSG alone for the management of these wounds.

METHOD

Data from patients undergoing management using IMBWM for a complex extremity wound coverage were collected.

RESULTS

Among the 109 patients studied, the wounds of 62 patients were managed using IMBWM and NPWT, and 47 were managed using IMBWM alone. The most common aetiology of these injuries was trauma. Wound size and location were similar for each group, ranging in size from 2-30cm² and being primarily on the forearm, followed by the leg and arm. There was a significantly greater take of the IMBWM+STSG with NPWT (96.8%) compared to without NPWT (85.1%, p=0.03). There were significantly fewer reapplications of the dermal matrix required in the NPWT group (3.2%) versus the non-NPWT group (14.9%, p=0.03). There were significantly fewer postoperative complications, prior to STSG, in the NPWT group (3.2%) versus the non-NPWT group (14.9%, p=0.03).

CONCLUSION

The combination of IMBWM with NPWT leads to a higher success rate, and can reduce the number of dermal matrix reapplications and postoperative complications, in the setting of complex extremity wounds. The use of IMBWM in combination with NPWT has the potential to improve both surgical procedures and patient outcomes in this setting.

Integra Dermal Regeneration Template in reconstructive surgery for cutaneous tumours: a two-year retrospective review

OBJECTIVE

Integra Dermal Regeneration Template (IDRT) (Integra LifeSciences, US) is a bioengineered dermal matrix that has been widely used in burn reconstruction since its first description. However, little is reported on its use in oncologic dermatological defects. Our objective was to evaluate reconstruction using IDRT on cutaneous tumour defects.

METHOD

We conducted a two-year retrospective review of patients with skin tumours who had an excision surgery, followed by reconstruction with IDRT, as a mid-step towards a final autograft procedure: a split-thickness skin graft. The records of all patients at a single academic institution were queried from the electronic medical record using data obtained from the operating surgeon.

RESULTS

We identified 13 patients with different tumour types and locations. The mean defect size was 105.92cm². The matrix take rate was 92.3% and average postoperative day for definite autograft was 20 days. Patients were followed for a period of up to 12 months. Of the patients, one had exposed bone without periosteum; another patient showed recurrence six months after matrix placement, requiring a new second two-stage IDRT-autograft procedure before radiation therapy. Patients reported complete satisfaction with the cosmetic, functional and oncological results. No cases of infection were encountered.

CONCLUSION

IDRT is a valid option for the reconstruction of oncologic surgical defects of the skin and can be used in different anatomical locations. Specifically, it is an alternative to the reconstructive ladder when grafts and local flaps are not possible in those patients, and an option for patients who will eventually need adjuvant radiotherapy.

Burn Wound Healing: Clinical Complications, Medical Care, Treatment, and Dressing Types: The Current State of Knowledge for Clinical Practice

According to the World Health Organization (WHO), it is estimated that each year approximately 11 million people suffer from burn wounds, 180,000 of whom die because of such injuries. Regardless of the factors causing burns, these are complicated wounds that are difficult to heal and are associated with high mortality rates. Medical care of a burn patient requires a lot of commitment, experience, and multidirectional management, including surgical activities and widely understood pharmacological approaches. This paper aims to comprehensively review the current literature concerning burn wounds, including classification of burns, complications, medical care, and pharmacological treatment. We also overviewed the dressings (with an emphasis on the newest innovations in this field) that are currently used in medical practice to heal wounds.

Wound healing properties of a fibrin-based dermal replacement scaffold

When serious cutaneous injury occurs, the innate wound healing process attempts to restore the skin's appearance and function. Wound healing outcome is affected by factors such as contraction, revascularisation, regeneration versus fibrosis and re-epithelialisation and is also strongly influenced by the pattern and extent of damage to the dermal layer. Dermal replacement scaffolds have been designed to substitute for lost tissue, provide a structure to promote dermal regeneration, and aid skin grafting, resulting in a superior healing outcome. In this study the wound healing properties of a novel fibrin-alginate dermal scaffold were assessed in the porcine wound healing model and also compared to two widely used dermal scaffolds and grafting alone. The fibrin-alginate scaffold, unlike the other scaffolds tested, is not used in combination with an overlying skin graft. Fibrin scaffold treated wounds showed increased, sustained superficial blood flow and reduced contraction during early healing while showing comparable wound closure, re-epithelialisation and final wound outcome to other treatments. The increase in early wound vascularisation coupled with a decrease in contraction and no requirement for a skin graft suggest that the fibrin-based scaffold could provide an effective, distinctive treatment option to improve healing outcomes in human patients.

Long-term experience with a collagen-elastin scaffold in combination with split-thickness skin grafts for the treatment of full-thickness soft tissue defects: improvements in outcome-a retrospective cohort study and case report

Purpose

The management of severe soft tissue injuries to the extremities with full-thickness wounds poses a challenge to the patient and surgeon. Dermal substitutes are used increasingly in these defects. The aim of this study was to investigate the impact of the type of injury on the success rate of Matriderm® (MD)-augmented split-thickness skin grafting, as well as the role of negative pressure wound therapy (NPWT) in preconditioning of the wounds, with a special focus on the reduction of the bioburden.

Methods

In this study, 45 wounds (44 affecting lower extremities (97.7%)), resulting from different types of injuries: soft tissue (ST), soft tissue complications from closed fracture (F), and open fracture (OF) in 43 patients (age 55.0 ± 18.2 years, 46.7% female), were treated with the simultaneous application of MD and split-thickness skin grafting. The study was designed as a retrospective cohort study from March 2013 to March 2020. Patients were stratified into three groups: ST, F, and OF. Outcome variables were defined as the recurrence of treated wound defects, which required revision surgery, and the reduction of bioburden in terms of reduction of number of different bacterial strains. For statistical analysis, Student’s t-test, analysis of variance (ANOVA), Mann–Whitney U test, and Pearson’s chi-squared test were used.

Results

There was no significant difference in the rate of recurrence in the different groups (F: 0%; OF: 11.1%; ST: 9.5%). The duration of VAC therapy significantly differed between the groups (F: 10.8 days; OF: 22.7 days; ST: 12.6 days (p < 0.05)). A clinically significant reduction of bioburden was achieved with NPWT (bacterial shift (mean (SD), F: − 2.25 (1.89); OF: − 1.9 (1.37); ST: − 2.6 (2.2)).

Conclusion

MD-augmented split-thickness skin grafting is an appropriate treatment option for full-thickness wounds with take rates of about 90%. The complexity of an injury significantly impacts the duration of the soft tissue treatment but does not have an influence on the take rate. NPWT leads to a relevant reduction of bioburden and is therefore an important part in the preconditioning of full-thickness wounds.

Salvage of a mangled limb with Matriderm® augmented split-skin grafting and maggot biodebridement

Salvage of a mangled limb can be a long and strenuous way, but it is feasible even with rather simple techniques such as augmented split-skin grafting and maggot biodebridement.

Implementation and Validation of Free Flaps in Acute and Reconstructive Burn Care

Microsurgical free flap reconstruction in acute burn care offers the option of reconstructing even challenging defects in a single stage procedure. Due to altered rheological and hemodynamic conditions in severely burned patients, it bears the risk of a higher complication rate compared to microsurgical reconstruction in other patients. To avoid failure, appropriate indications for free flap reconstruction should be reviewed thoroughly. Several aspects concerning timing of the procedure, individual flap choice, selection and preparation of the recipient vessels, and perioperative measures must be considered. Respecting these specific conditions, a low complication rate, comparable to those seen in microsurgical reconstruction of other traumatic limb defects, can be observed. Hence, the free flap procedure in acute burn care is a relatively safe and reliable tool in the armamentarium of acute burn surgery. In reconstructive burn care, microsurgical tissue transfer is routinely used to treat scar contractures. Due to the more robust perioperative condition of patients, even lower rates of complication are seen in microsurgical reconstruction.

[Multicenter study of the effectiveness of antiscar therapy in patients at different age periods]

OBJECTIVE

Was to evaluate the effectiveness of anti-scar treatment with Contractubex gel in children and adults.

MATERIAL AND METHODS

A group of researchers based on clinical hospitals and university medical clinics carry out the multicenter study to evaluate the effectiveness of anti-scar treatment with Contractubex gel containing cepalin, allantoin and heparin, with its early appointment in groups of children from 12 to 18 years old and adults from 21 to 35 years old. The study included data from 216 patients. Patients of both age groups were initially divided into two: the main and control ones with an equal distribution according to the type of surgical intervention (hernia repair and appendectomy), age, gender, and anamnestic data. The dynamic observation was carried out using two rating scales - filled out by a doctor (Vancouver scale) and a patient (author's rating scale in the Scar Diary mobile application).

RESULTS

Based on the results of the analysis of the data obtained, a high efficiency of the use of Contractubex gel at the early stages of scar formation among patients of the main group in comparison with the control was revealed. By 90 days, the treatment result according to the Vancouver scale was 0,16±0,1 points in the main group and 0,39±0,2 points in the control group. At the same time, with a dynamic scale for assessing the cicatricial process, there was a significant (p<0.05) improvement in the main group (0,2±0,06 points) compared with the control group (0,6±0,17 points). In addition, was noticed the strong commitment to anti-scar treatment in pediatric patients.

CONCLUSIONS

The work confirms the undoubted need for anti-scar treatment in the early stages of scar formation after surgical interventions, which accelerates the psychophysical rehabilitation of patients after surgery and improves the quality of life.

A Concise Review on Tissue Engineered Artificial Skin Grafts for Chronic Wound Treatment: Can We Reconstruct Functional Skin Tissue In Vitro?

Chronic wounds occur as a consequence of a prolonged inflammatory phase during the healing process, which precludes skin regeneration. Typical treatment for chronic wounds includes application of autografts, allografts collected from cadaver, and topical delivery of antioxidant, anti-inflammatory, and antibacterial agents. Nevertheless, the mentioned therapies are not sufficient for extensive or deep wounds. Moreover, application of allogeneic skin grafts carries high risk of rejection and treatment failure. Advanced therapies for chronic wounds involve application of bioengineered artificial skin substitutes to overcome graft rejection as well as topical delivery of mesenchymal stem cells to reduce inflammation and accelerate the healing process. This review focuses on the concept of skin tissue engineering, which is a modern approach to chronic wound treatment. The aim of the article is to summarize common therapies for chronic wounds and recent achievements in the development of bioengineered artificial skin constructs, including analysis of biomaterials and cells widely used for skin graft production. This review also presents attempts to reconstruct nerves, pigmentation, and skin appendages (hair follicles, sweat glands) using artificial skin grafts as well as recent trends in the engineering of biomaterials, aiming to produce nanocomposite skin substitutes (nanofilled polymer composites) with controlled antibacterial activity. Finally, the article describes the composition, advantages, and limitations of both newly developed and commercially available bioengineered skin substitutes.