Evaluation of Host Tissue Integration, Revascularization, and Cellular Infiltration Within Various Dermal Substrates

Comparative Analysis of Animal-Derived vs Fully Synthetic Acellular Dermal Matrices in Reconstructive Surgery: An Examination of Clinical, Aesthetic, and Economic Measures

INTRODUCTION

The fully synthetic skin substitute, NovoSorb Biodegradable Temporizing Matrix (BTM), may be a cost-effective alternative to the animal-derived Integra Dermal Regeneration Template (IDRT). However, the current literature insufficiently compares the two. Therefore, our study compared clinical, aesthetic, and economic outcomes in treating soft tissue wounds with IDRT, an animal-derived template, vs BTM, a fully synthetic template.

METHODS

Our single-center retrospective study compared outcomes of 26 patient cases treated with BTM (57.7%) or IDRT (42.3%) during 2011-2022.

RESULTS

The mean surgery time was significantly shorter in BTM cases (1.632 ± 0.571 hours) compared with IDRT cases (5.282 ± 5.102 hours, P = 0.011). Median postoperative hospital stay was notably shorter for BTM placement than IDRT placement (0.95 vs 6.60 days, P = 0.003). The median postoperative follow-up length approached a shorter duration in the BTM group (P = 0.054); however, median follow-up visits were significantly lower in the BTM group compared with the IDRT group (5 vs 14, P = 0.012). The median duration for complete wound closure was shorter for BTM (46.96 vs 118.91 days, P = 0.011). Biodegradable Temporizing Matrix demonstrated a notably lower infection rate (0.0%) compared with IDRT (36.4%, P = 0.022). Integra Dermal Regeneration Template exhibited higher wound hypertrophy rates (81.8%) than BTM (26.7%, P = 0.015). Revisionary surgeries were significantly more frequent in the BTM group (P < 0.001). Failed closure, defined as requiring one or more attempts, exhibited a significant difference, with a higher risk in the IDRT group (26.7%) compared with BTM (6.7%, P = 0.003). Biodegradable Temporizing Matrix showed a lower mean Vancouver Scar Scale adjusted fraction (0.279) compared with IDRT (0.639, P < 0.001). Biodegradable Temporizing Matrix incurred lower costs compared with IDRT but displayed a lower mean profit per square centimeter ($10.63 vs $22.53, P < 0.001).

CONCLUSION

Economically, although the net profit per square centimeter of dermal template may favor IDRT, the ancillary benefits associated with BTM in terms of reduced hospital stay, shorter surgery times, fewer follow-up visits, and lower revisionary surgery rates contribute substantially to overall cost-effectiveness. Biodegradable Temporizing Matrix use reflects more efficient resource use and potential cost savings, aligning with broader trends in healthcare emphasizing value-based and patient-centered care.

The Autonomization Principle in Vascularized Flaps: An Alternative Strategy for Composite Tissue Scaffold In Vivo Revascularization

Autonomization is a physiological process allowing a flap to develop neo-vascularization from the reconstructed wound bed. This phenomenon has been used since the early application of flap surgeries but still remains poorly understood. Reconstructive strategies have greatly evolved since, and fasciocutaneous flaps have progressively replaced muscle-based reconstructions, ensuring better functional outcomes with great reliability. However, plastic surgeons still encounter challenges in complex cases where conventional flap reconstruction reaches its limitations. Furthermore, emerging bioengineering applications, such as decellularized scaffolds allowing a complex extracellular matrix to be repopulated with autologous cells, also face the complexity of revascularization. The objective of this article is to gather evidence of autonomization phenomena. A systematic review of flap autonomization is then performed to document the minimum delay allowing this process. Finally, past and potential applications in bio- and tissue-engineering approaches are discussed, highlighting the potential for in vivo revascularization of acellular scaffolds.

Scaffold- and graft-based biological augmentation of rotator cuff repair: an updated systematic review and meta-analysis of preclinical and clinical studies for 2010-2022

BACKGROUND

Despite advancements in the surgical techniques of rotator cuff repair (RCR), there remains a high retear rate. Biological augmentation of repairs with overlaying grafts and scaffolds may enhance healing and strengthen the repair construct. This study aimed to investigate the efficacy and safety of scaffold-based (nonstructural) and overlay graft-based (structural) biological augmentation in RCR (excluding superior capsule reconstruction and bridging techniques) in both preclinical and clinical studies.

METHODS

This systematic review was performed in adherence to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, as well as guidelines outlined by The Cochrane Collaboration. A search of the PubMed, Embase, and Cochrane Library databases from 2010 until 2022 was conducted to identify studies reporting the clinical, functional, and/or patient-reported outcomes of ≥1 biological augmentation method in either animal models or humans. The methodologic quality of included primary studies was appraised using the Checklist to Evaluate a Report of a Non-pharmacological Trial (CLEAR-NPT) for randomized controlled trials and using the Methodological Index for Non-randomized Studies (MINORS) for nonrandomized studies.

RESULTS

A total of 62 studies (Level I-IV evidence) were included, comprising 47 studies reporting outcomes in animal models and 15 clinical studies. Of the 47 animal-model studies, 41 (87.2%) demonstrated biomechanical and histologic enhancement with improved RCR load to failure, stiffness, and strength. Of the 15 clinical studies, 10 (66.7%) illustrated improvement in postoperative clinical, functional, and patient-reported outcomes (eg, retear rate, radiographic thickness and footprint, and patient functional scores). No study reported a significant detriment to repair with augmentation, and all studies endorsed low complication rates. A meta-analysis of pooled retear rates demonstrated significantly lower odds of retear after treatment with biological augmentation of RCR compared with treatment with non-augmented RCR (odds ratio, 0.28; P < .00001), with low heterogeneity (I2 = 0.11).

CONCLUSIONS

Graft and scaffold augmentations have shown favorable results in both preclinical and clinical studies. Of the investigated clinical grafts and scaffolds, acellular human dermal allograft and bovine collagen demonstrate the most promising preliminary evidence in the graft and scaffold categories, respectively. With a low risk of bias, meta-analysis revealed that biological augmentation significantly lowered the odds of retear. Although further investigation is warranted, these findings suggest graft and scaffold biological augmentation of RCR to be safe.

FDG Localization in Acellular Dermal Matrix, a Potential Cause of Nonpernicious Uptake Following Breast Reconstruction Surgery

ABSTRACT

A 47-year-old woman with invasive lobular carcinoma of the left breast underwent prophylactic double mastectomy which also incidentally revealed follicular lymphoma of the right breast. Reconstruction was achieved with bilateral silicone implants and acellular dermal matrix (ADM), a biological scaffold material providing mechanical support. Twelve days thereafter, staging PET/CT demonstrated symmetric moderate FDG uptake corresponding to location of the ADM slings, suspected to reflect cellular engraftment onto the ADM and confirmed by near-complete resolution at 3-month follow-up study. FDG uptake related to ADM should be recognized as reflecting expected cellular incorporation into the matrix, rather than recurrent tumor or infection.

In vitro and in vivo evaluation of a modified porcine acellular dermal matrix for soft tissue augmentation

OBJECTIVES

To evaluate the effects of a modified porcine acellular dermal matrix (P-ADM), subepithelial connective tissue graft (SCTG) and other commercial bovine acellular dermal matrix membrane materials (B-ADM) on gingival soft tissue augmentation in the oral esthetic zone.

MATERIAL AND METHODS

The characteristics of P-ADM were observed by scanning electron microscope (SEM), Hematoxylin and eosin (H&E) and Masson's trichrome staining (Masson staining). The biocompatibility of P-ADM was verified by CCK8, phalloidin and living/dead cell staining. Beagle dog models were constructed and the thickness of gingiva was analyzed by the intraoral scanner. The morphology was observed by H&E and Masson staining.

RESULTS

Scanning electron microscopy, H&E and Masson staining showed that the P-ADM was mainly composed of collagen fibers, with no component of nuclear. The results of CCK8, phalloidin and living/dead cell staining indicated that the P-ADM had good cytocompatibility and no cytotoxicity. Human gingival fibroblasts were able to adhere and stretch on the surface of the material with pseudopodia. The SCTG group outperformed the B-ADM and P-ADM groups in terms of effectiveness, according to the analysis of digital oral scanning data at various time points following incremental soft tissue surgery. Compared with the B-ADM group, the effect of soft tissue increment was better in the P-ADM group.

CONCLUSIONS

P-ADM, as a biocompatible biomaterial, can be used as an alternative biomaterial for oral soft tissue thickening. However, the results of this study need to be verified by more clinical trials.

Successful Treatment of Wound Dehiscence by Innovative Type 1 Collagen Flowable Gel: A Case Report

The growing demand for postbariatric body-contouring surgery after massive weight loss goes hand-in-hand with an increase in wound complications. Consequently, surgical reoperation or conservative management is necessary and represents a difficult challenge to healthcare professionals. Moreover, it is well known that postbariatric patients present aberrant wound healing due to multifactorial causes, such as preoperative illness, nutritional deficiencies, and vascular disease. To treat such complex wounds, several methods have been recommended, such as the use of negative pressure wound therapy, tissue-engineered skin substitutes, and collagen-based wound dressings. The case presented here is of a patient with deep wound dehiscence of the inner left thigh, 1 week after a medial thigh lift procedure, successfully managed with Vergenix Flowable Gel, a human recombinant type I collagen produced in plants. After 2 weeks of treatment, wound dehiscence was replaced with granulation tissue, and after 4 weeks, the patient was completely healed, with an acceptable aesthetic outcome of the surgical scar.

DermACELL Acellular Dermal Matrix in Oncologic Breast Reconstruction: A Cohort Study and Systematic Review

Acellular dermal matrices (ADMs) are commonly used in tissue expander and direct-to-implant reconstruction following mastectomy. Few studies have reported outcomes of DermACELL use or compared DermACELL with AlloDerm ADM. This study sought to compare outcomes of DermACELL and AlloDerm in oncologic breast reconstruction and to review the literature reporting outcomes of patients undergoing reconstruction using DermACELL.

New Method for Genital Aesthetic Surgery: An Easy-To-Learn Two-Step Approach With Acellular Dermal Matrix (ADM)

BACKGROUND

Vaginal laxity, usually accompanied with prolapse symptoms, affects women's sexual satisfaction and quality of life. Vaginal tightening surgery aims to reinforce the peri-vaginal muscle strength and restore the normal vaginal anatomy.

OBJECTIVES

The objective of this study was to introduce a new surgical approach with vaginal tightening using acellular dermal matrix (ADM).

METHODS

In this retrospective study, we analyzed data from 80 patients with vaginal laxity who underwent surgery from April 2017 to April 2021. Three-dimensional transvaginal ultrasound (3D-TVS) and the Female Sexual Function Index (FSFI) were evaluated among the patients.

RESULTS

The mean age of the patients was 44.6 years. The mean patient follow-up was 13.2 months. No infection, rectovaginal fistula, or implant explantation occurred. 3D-TVS demonstrated a significant reduction of introital diameter on a maximum Valsalva maneuver (2.3 cm vs. 4.1 cm; p<0.05) and the reconstruction of acute vaginal angulation. FSFI orgasm subscore increased significantly.

CONCLUSIONS

Vaginal tightening with ADM is a minimally invasive surgery with safety and efficacy for patients with vaginal laxity.

Comparison of Skin Substitutes for Acute and Chronic Wound Management

Chronic and acute wounds, such as diabetic foot ulcers and burns, respectively, can be difficult to treat, especially when autologous skin transplantations are unavailable. Skin substitutes can be used as a treatment alternative by providing the structural elements and growth factors necessary for reepithelialization and revascularization from a nonautologous source. As of 2020, there are 76 commercially available skin substitute products; this article provides a review of the relevant literature related to the major categories of skin substitutes available.

Histologic case series of human acellular dermal matrix in superior capsule reconstruction

BACKGROUND

Acellular dermal matrix (ADM) allografts are commonly used in the surgical treatment of complex and irreparable rotator cuff tears. Multiple studies report that superior capsule reconstruction (SCR) using ADM has resulted in short-term clinical success as assessed via radiographic and patient-reported outcomes. However, limited information is available regarding the biologic fate of these grafts in human subjects. This case series describes histologic results from 8 patients who had reoperations, during which the previously implanted ADMs were removed. These explanted ADMs were subjected to histologic analysis with the hypothesis that they would have evidence of recellularization, revascularization, and active remodeling.

METHODS

Eight patients, 38-82 years old, underwent reoperation 6-38 months after undergoing SCR. ADM explants were voluntarily shipped to the manufacturer for histologic analysis. Each graft's structure and composition were qualitatively evaluated by 1 or more of the following histologic stains: hematoxylin and eosin, safranin O, and Russell-Movat pentachrome. Pan-muscle actin staining also assessed the level of neovascularization, potential myoblast or myocyte infiltration, and muscle tissue development in the graft, and was analyzed to determine the proportion of graft that had been recellularized in situ.

RESULTS

Grafts showed varying levels of gross and microscopic incorporation with the host. An uneven, but high, overall degree of recellularization, revascularization, and active remodeling was observed. The degree of remodeling correlated with implant duration. These results are consistent with successful biologic reconstruction of the superior shoulder capsule.

CONCLUSIONS

The present histologic analysis suggests that ADMs used in SCR undergo active recellularization, revascularization, and remodeling as early as 6 months after implantation, and that graft recellularization positively correlates with duration of implantation. These results represent a significant advancement in our knowledge regarding biologic incorporation of ADMs used in SCR.

Ready-to-Use Micronized Human Acellular Dermal Matrix to Accelerate Wound Healing in Diabetic Foot Ulcers: A Prospective Randomized Pilot Study

OBJECTIVE

To examine and report clinical outcomes of a ready-to-use micronized dermal matrix for diabetic foot ulcers (DFUs) and compare it to treatment with conventional negative-pressure wound therapy (NPWT) only.

METHODS

The researchers randomly allocated 30 DFUs Wagner grade 2 or higher from 30 adult patients into two groups. The control group (n = 15) was treated with conventional NPWT, and the experimental group (n = 15) was treated with micronized dermal matrix and NPWT. The researchers evaluated the following outcomes: granulation tissue formation, proportion of patients with closed or granulated wounds at 42 and 120 days, achievement of complete wound healing in the 6 months of follow-up, and intervals from enrollment to final surgical procedures.

RESULTS

All 15 wounds treated with the micronized matrix showed healthy granulation tissue without noticeable complications during follow-up. At 42 days, 46.7% of wounds in the experimental group had closed compared with 28.6% in the conventional NPWT group (P = .007). At 120 days, 86.7% of the experimental group had completely closed wounds, compared with 57.1% in the conventional therapy group (P = .040). During the 6-month follow-up period, 93.3% of the experimental group achieved complete wound healing compared with 85.7% of the conventional therapy group (P = .468).

CONCLUSIONS

The healing outcomes for DFUs in the experimental group were superior when micronized matrix treatment was combined with NPWT.

A Case of Large Aplasia Cutis Congenita with Underlying Skull Defect: Effective Surgical Treatment with Integra® Dermal Regeneration Template

INTRODUCTION

Aplasia cutis congenita (ACC) is a rare congenital abnormality characterized by the absence of a portion of skin at birth which most commonly involves the scalp and can affect the galea, the pericranium, the bone, and the dura mater. It can be an isolated condition or associated with other disorders.

CASE REPORT

We present a case of ACC with a large defect of the scalp and the underlying bone treated with the use of Integra® Dermal regeneration template. At 5 months of follow-up, the wound is completely healed and the bony defect greatly reduced. Contraction of the area of alopecia was observed.

DISCUSSION

Several surgical and conservative options have been described to treat this congenital condition: advanced dressing, skin graft, local flaps, free flaps, and other methods. In our case, we used Integra® Dermal templates which provide a barrier for infections, promote cellular activity for a rapid vascularization, and improve healing.

A Randomized Controlled Trial Comparing Alloderm-RTU with DermACELL in Immediate Subpectoral Implant-Based Breast Reconstruction

Background: The effectiveness of different acellular dermal matrices (ADM) used for implant-based reconstruction immediately following mastectomy is an important clinical question. A prospective randomized clinical trial was performed to evaluate the superiority of DermACELL over Alloderm-RTU in reducing drain duration. Methods: Patients undergoing mastectomy with subpectoral immediate and permanent implant-based breast reconstruction were randomized to Alloderm-RTU or DermACELL. The primary outcome was seroma formation, measured by the duration of postoperative drain placement. Secondary outcomes included: post drain removal seroma aspiration, infection, redbreast syndrome, wound dehiscence, loss of the implant, and unplanned return to the operating room. Results: 62 patients were randomized for 81 mastectomies (41 Alloderm-RTU, 40 DermACELL). Baseline characteristics were similar. There was no statistically significant difference in mean drain duration (p = 0.16), with a trend towards longer duration in the Alloderm-RTU group (1.6 days; 95%CI, 0.7 to 3.9). The overall rate of minor and major complications were statistically similar between the two groups; although patients with Alloderm-RTU had 3 times as many infections requiring antibiotics (7.9% vs. 2.5%) with a risk difference of 5.4 (95%CI −4.5 to 15.2), and twice as many unplanned returns to the operating room (15.8% vs. 7.5%) with a risk difference of 8.3 (95% CI −5.9 to 22.5) as DermACELL. Conclusion: This is the first prospective randomized clinical trial comparing the two most commonly used human-derived ADMs. There was no statistically significant difference in drain duration, minor, or major complications between DermACELL over Alloderm-RTU in immediate subpectoral permanent implant-based breast reconstruction post-mastectomy.

In Vitro Analysis of Histology, Mechanics, and Safety of Radiation-free Pre-hydrated Human Acellular Dermal Matrix

Purpose

Acellular dermal matrix (ADM) supports tissue expanders or implants in implant-based breast reconstruction. The characteristics of ADM tissue are defined by the manufacturing procedure, such as decellularization, preservation, and sterilization, and are directly related to clinical outcomes. This study aimed to compare the properties of a new pre-hydrated-ADM (H-ADM-low) obtained using a decellularization reagent reduction process with a low concentration of detergent with those of radiation-sterilized H-ADM and freeze-dried ADM (FD-ADM).

Methods

ADMs were evaluated in terms of structure, mechanical quality, and cytotoxicity using histochemical staining, tensile strength testing, and in vitro cell viability analysis.

Results

The tissue structure of H-ADM-low (CGDERM ONE-STEP) was similar to that of native skin despite complete decellularization. By contrast, in FD-ADM, the tissue structure was damaged by the freeze-drying process, and radiation-sterilized H-ADM showed a compact fibrillar arrangement. Furthermore, matrix components such as collagen and elastin were preserved in H-ADM-low, whereas a loss of elastin fibers with fragmented distribution was observed in radiation-sterilized H-ADMs. H-ADM-low's tensile strength (58.84 MPa) was significantly greater than that of FD-ADM (38.60 MPa) and comparable with that of radiation-sterilized H-ADMs. The residual detergent content in H-ADM-low (47.45 mg/L) was 2.67-fold lower than that of H-ADM decellularized with a conventional detergent concentration (126.99 mg/mL), and this finding was consistent with the cell viability results (90.7% and 70.7%, respectively), indicating that H-ADM-low has very low cytotoxicity.

Conclusions

H-ADM-low produced through aseptic processes retains the original tissue structure, demonstrates excellent mechanical properties, and does not affect cell viability. Therefore, this newer H-ADM is suitable for use in implant-based breast reconstruction.

What happens to an acellular scar matrix after implantation in vivo? A histological and related molecular biology study

It has been established that scar acellular matrices (AMs), which allow cell proliferation, have similar characteristics. The aim of this study was to investigate the repair effect of scar AMs on animals, thus providing a reference for clinical application. Selected mature and immature scar AMs were implanted into animals, and then a negative control group was set for comparison. The effect of scar AMs on wound healing was observed through tissue staining, RT-qPCR, and immunohistochemistry. The materials showed milder inflammation and faster extracellular matrix (ECM) deposition than the negative control group. The ECM deposition and new vessels increased over time. However, the arrangement of ECM in mature scar AM was more regular than in immature scar AM and the negative control group, and more new vessels grew in the mature scar AM group than in the immature scar AM group and negative control group over the same period. The transforming growth factor-β level was elevated at one month, two months, and six months. COLA1 and vimentin levels all peaked at six months. Matrix metalloproteinase and TIMP1 were also elevated at different months. Collectively, scar AMs can effectively promote wound healing and vascularization. Mature scar AMs have a better regeneration effect.

A comparison of patient-reported outcomes between Alloderm and Dermacell in immediate alloplastic breast reconstruction: A randomized control trial

BACKGROUND

Alloderm and Dermacell are the two leading human acellular dermal matrices (ADM) in immediate breast reconstruction (IBR). Despite differences in sterility, consistency, thickness and cost, there are no comparative trials to date to compare patient-reported outcome measures (PROM) between the two products. The purpose of this study was to determine if there was a difference in patient-reported outcomes (as measured by the BREAST-Q) between patients reconstructed with Alloderm and Dermacell.

METHODS

A single center, open-label, randomized control trial of patients undergoing IBR with an implant for breast cancer or breast cancer prophylaxis was performed. Patients were randomized to either Alloderm or Dermacell. Baseline demographic data were compared, and linear mixed models were used to identify associations with BREAST-Q over time.

RESULTS

Between June 2016 and October 2018, 62 patients were randomized into two groups, 31(50%) Alloderm and 31(50%) Dermacell. Of these, 23(74%) patients in the Alloderm group and 27(87%) patients of the Dermacell group filled out BREAST-Q questionnaires. Baseline BREAST-Q scores with respect to satisfaction with breasts, psychosocial well-being, sexual well-being, and physical well-being were similar between groups (p>0.05). At 3 months postoperatively, the Alloderm group had a statistically significant improvement with respect to satisfaction with breasts (67 vs 53, p = 0.03), satisfaction with overall results (85 vs 61, p = 0.003), satisfaction with the surgeon (89 vs 67, p = 0.01), and satisfaction with information provided (74 vs 59, p = 0.02). At 12 months postoperatively, there were no statistically significant differences in PROM between groups (p>0.05).

CONCLUSION

We report the first randomized controlled trial to date comparing patient-reported outcomes of the two most commonly used ADMs in IBR in Canada. Although a short-term analysis favors the use of Alloderm, there does not appear to be any difference in outcomes between the two products in the longer term.

Acellular dermal matrix as an alternative to autologous fascia lata for skull base repair following extended endoscopic endonasal approaches

BACKGROUND

Skull base reconstruction after extended endoscopic endonasal approaches (EEAs) can be challenging. In addition to the nasoseptal flap, which has been adopted by most centers, autologous fascia lata is also often utilized. Harvesting of fascia lata requires a separate thigh incision, may prolong recovery, and results in a visible scar. In principal, the use of non-autologous materials would be preferable to avoid a second incision and maintain the minimally invasive nature of the approach, assuming the CSF leak rate is not compromised.

OBJECTIVE

To assess the efficacy of acellular dermal matrix (ADM) as a non-autologous alternative to autologous fascia lata graft for watertight closure of the cranial base following EEAs.

METHODS

A retrospective chart review of extended EEAs performed before and after the transition from fascia lata to ADM was performed. Cases were frequency matched for approach, pathology, BMI, use of lumbar drainage, and tumor volume. Power analysis was performed to estimate the sample size needed to demonstrate non-inferiority.

RESULTS

ADM was used for watertight closure of the cranial base in 19 consecutive extended endoscopic endonasal approaches (16 gasket-seals and 3 buttons) with 1 postoperative CSF leak at the last follow-up (median 5.3, range 1.0-12.6 months). All patients had high-flow intraoperative leaks. The cohort included 8 meningiomas, 8 craniopharyngiomas, 2 chordomas, and 1 pituicytoma ranging in size from 0.2 to 37.2cm³ (median 5.5, IQR 2.8-13.3 cm³). In 19 historical controls who received fascia lata, there were 2 postoperative CSF leaks.

CONCLUSIONS

Preliminary results suggest that ADM provides a non-inferior non-autologous alternative to fascia lata for watertight gasket-seal and button closures following extended EEAs, potentially reducing or eliminating the need to harvest autologous tissue.

Comparison of inflammatory response and synovial metaplasia in immediate breast reconstruction with a synthetic and a biological mesh: a randomized controlled clinical trial

The aim of this study was to compare inflammatory response and synovial metaplasia in implant-based immediate breast reconstruction with a biological mesh (Veritas^®) with that of a synthetic mesh (TIGR^® Matrix Surgical Mesh). We hypothesize that the inflammatory response and formation of synovial metaplasia might be different and the rate of capsular contracture therefore different. The patients were recruited from the Gothenburg TIGR^®/Veritas^® Study (ClinicalTrials.Gov identifier NCT02985073). All referrals for bilateral immediate breast reconstruction were assessed for inclusions. During the operation, the patients were randomized to which sides the biological and the synthetic mesh were going to be applied. During the implant exchange biopsies were taken. Biopsies were taken from 30 breasts in 15 patients. There seem to be more myofibroblast and neovascularization in the biological meshes than in the synthetic and the collagen fibers seem to be aligned in an irregular pattern with both parallel and vertical fibers. In the synthetic meshes, there were more giant cells and foreign body reaction and the collagen fibers were loosely and well aligned, oriented parallel to the surface of the implant. Synovial metaplasia was seen in the majority of both the biological and the synthetic meshes. The histological patterns in early capsules from biological and synthetic meshes vary considerably. Nonetheless, it is unknown what role different cell types have in capsular formation in the long run and there was no difference in clinical capsular contracture at the clinical follow-up in this study.

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

The advent of dermal regeneration templates has fostered major advances in the treatment of acute burns and their sequelae, in the last three decades. Both data on morphological aspects of the newly-formed tissue, and clinical trials comparing different templates, are few. The goal of this study was to prospectively analyze the outcome of randomized patients treated with two of the existing templates, followed by thin skin autograft. They are both 2 mm-thick bovine collagen templates (Matriderm® and Integra®), the latter includes a superficial silicone layer. Surgery was performed on patients with impaired mobility resulting from burn sequelae (n = 12 per template) in a two-step procedure. Negative pressure therapy was applied after surgery; patients were monitored for 12 months. No intra or postoperative complications were observed. Data on scar skin quality (Vancouver scar scale), rate of mobility recovery, and graft contraction were recorded; as well as morphological analyses at light microscopical level. Improvement in mobility and skin quality were demonstrated along with graft contraction, in all patients. The double layer template showed the best performance in retraction rate, skin quality and mobility recovery. The subepidermal newly-formed connective tissue showed no histoarchitectural differences between the templates. The double layer template was not absorbed up to 12 months after placement.

A retrospective review of breast reconstruction outcomes comparing AlloDerm and DermaCELL

Acellular dermal matrix (ADM) has become an accepted and advantageous adjunct to alloplastic breast reconstruction. The increase in demand has led to an upsurge of dermal-based products, both human and animal derived. There are few direct ADM comparative studies, but it is unclear whether there are any differences in complication rates. Our primary objective was to determine whether there is a difference in outcomes between AlloDerm and DermACELL in immediate alloplastic breast reconstruction.

A retrospective chart review of those who underwent immediate alloplastic breast reconstruction from January to December 2016 was performed. This encompassed 64 consecutive patients (95 breasts) with tissue expander or direct-to-implant reconstruction and either AlloDerm or DermACELL ADM. Demographics, particulars of the surgery, additional treatments and complications were all recorded. Differences in seroma, haematoma and infection rates, as well as more serious complications including implant replacement, capsular contracture and failure, were all reviewed.

The groups were comparable in terms of age, BMI and relevant comorbidities. Mastectomy weight and resulting implant volume were higher in the DermACELL group, with volume reaching statistical significance (p = 0.001). With an average follow-up of 18 months, there was no difference in capsular contraction or implant replacement. However, in those who developed capsular contracture in the DermACELL group, more breasts had no history of radiation, which was significant (p = 0.042). Overall, there were no significant differences in complication rates of seroma, haematoma, mastectomy flap necrosis and infection.

The Use of a Hypoallergenic Dermal Matrix for Wrapping in Peripheral Nerve Lesions Regeneration: Functional and Quantitative Morphological Analysis in an Experimental Animal Model

INTRODUCTION

The aim of this research was to test, in an animal model, the nerve regeneration technique with a hypoallergenic acellular dermal matrix used to wrap the microsurgical neural suture.

MATERIALS AND METHODS

Two groups of rats received the cut of limb right median nerves. The regeneration technique considers for both groups an end-to-end nerve suture. In the experimental group (A) was used also a wrapping protocol by a conduit of collagen matrix currently used in oral surgery. The animals underwent functional grasping tests (at 1, 3, 5, and 7 months) and a histological and quantitative analysis of distal nerve was performed at the end of experimental time.

RESULT

After seven months, the grasping test reveals functional recovery in each tested animal; this improvement is more evident in Group A. The fibers appear well organized with restored myelin sheaths in both groups. Group A showed a great quantity of connective tissue surrounding the nerve. The quantitative morphology analysis in both groups shows a similar fibers density, fiber diameter, and myelin thickness. The differences between the groups in axon mean diameter are significant. In Group A M/d, D/d, and g-ratio is significantly higher compared to control group.

CONCLUSIONS

Histological and functional assessments show a functional recovery of the injured nerve in the test groups, stressed by the results of the grasping tests and the meaningful increasing in fiber diameter and higher g-ratio. Moreover, a connective tissue cuff distinguishes the distal portion of the injured nerve. Considering the easy availability and handling of the material used in this study we can conclude that this experimental technique can be considered as a valid alternative to protect nerves in nerve wrap surgery.

Allograft Tissue Safety and Technology

Allograft tissues are commonly used by orthopedic surgeons and are processed using a variety of technologies to increase safety and clinical use. For safety, although disease transmission is a tangible risk, this possibility has been dramatically minimized through modern tissue-processing methods. These include steps to prevent processing tissues with unacceptable bioburden through rigorous screening using donor medical and social histories along with microbial testing of recovered tissue and viral testing of donor serum. Potential bioburden is also controlled through aseptic recovery and processing methods and then reduced through disinfection steps that can include antibiotics, detergents, mechanical process, chemical solutions, and terminal sterilization. Processing steps may also include decellularization methods to lower immunogenic potential of some tissues. To enhance fusion potential of bone void fillers, demineralization steps may be used, and the resultant demineralized bone matrices may be combined with a carrier to improve handling. Bone void fillers and osteochondral allografts may also be specially processed to retain a living cellular component. To preserve relevant biological, biochemical, and physical properties of allografts for clinical use and ease of handling, a number of methods may be used which include: (1) refrigeration in media, (2) freeze-drying, (3) cryopreservation, (4) freezing, and (5) media storage at room temperature. As academic and industry research continue to drive advances, the future direction of allograft tissue likely includes injectables, coatings, cellular therapies, and combinations with other materials. The technology approaches outlined here will be further described along with future directions.

Revascularization of AlloDerm Used during Endoscopic Skull Base Surgery

Objectives  AlloDerm is an acellular dermal matrix often used for reconstruction throughout the body. AlloDerm has been shown to undergo revascularization when used to reconstruct soft tissue such as in abdominal wall reconstruction. In this study, the authors review the literature on revascularization of AlloDerm and demonstrate the histologic findings of AlloDerm after implantation during skull base reconstruction. Study Design  Literature review and case reports. Setting  Tertiary Care Institution Participants  Patients from a tertiary care institution Main Outcome Measures  Histologic slides are evaluated and compared with nonimplanted AlloDerm. Methods  The authors review a case of explanted AlloDerm that had been used for skull base reconstruction after endoscopic skull base surgery. Results  Upon reviewing the histologic slides of explanted AlloDerm to nonimplanted AlloDerm, we demonstrate revascularization of AlloDerm when used in skull base reconstruction. Representative slides will be included. Conclusions  AlloDerm undergoes revascularization when used for skull base reconstruction.

Delivery systems of current biologicals for the treatment of chronic cutaneous wounds and severe burns

While wound therapy remains a clinical challenge in current medical practice, much effort has focused on developing biological therapeutic approaches. This paper presents a comprehensive review of delivery systems for current biologicals for the treatment of chronic wounds and severe burns. The biologicals discussed here include proteins such as growth factors and gene modifying molecules, which may be delivered to wounds free, encapsulated, or released from living systems (cells, skin grafts or skin equivalents) or biomaterials. Advances in biomaterial science and technologies have enabled the synthesis of delivery systems such as scaffolds, hydrogels and nanoparticles, designed to not only allow spatially and temporally controlled release of biologicals, but to also emulate the natural extracellular matrix microenvironment. These technologies represent an attractive field for regenerative wound therapy, by offering more personalised and effective treatments.

What happens to an acellular dermal matrix after implantation in the human body? A histological and electron microscopic study

Acellular matrices are used for various purposes and they have been studied extensively for their potential roles in regenerating tissues or organs. The acellular matrix generates physiological cues that mimic the native tissue microenvironment. Acellular dermal matrix (ADM) is a soft connective tissue graft generated by a decellularization process that preserves the intact extracellular skin matrix. Upon implantation, this structure serves as a scaffold for donor-side cells to facilitate subsequent incorporation and revascularization. In breast reconstruction, ADM is used mainly for lower pole coverage and the shaping of a new breast. It helps control the positioning of the implant in the inframammary fold, and prevents the formation of contractile pseudocapsule around the breast implant. In this study, we provide a comprehensive histological description of ADM used for human breast reconstruction over the course of several months following implementation. Using immunohistochemical methods (a panel of 12 antibodies) coupled with optical and transmission electron microscopy, we confirmed that the original acellular dermal matrix became recolonized by fibroblasts and myofibroblasts, and also by various other free cells of the connective tissue (lymphocytes, macrophages and multinucleated giant cells, granulocytes, mast cells) after implantation into the patient’s body. Within the implanted ADM, there was a relatively rapid ingrowth of blood vessels. Lymphatic vessels were only detected in one case 9 months after the implantation of the ADM. These results suggest that lymphangiogenesis is a longer process than angiogenesis.

Stem cells, niches and scaffolds: Applications to burns and wound care

The importance of skin to survival, and the devastating physical and psychological consequences of scarring following reparative healing of extensive or difficult to heal human wounds, cannot be disputed. We discuss the significant challenges faced by patients and healthcare providers alike in treating these wounds. New state of the art technologies have provided remarkable insights into the role of skin stem and progenitor cells and their niches in maintaining skin homeostasis and in reparative wound healing. Based on this knowledge, we examine different approaches to repair extensive burn injury and chronic wounds, including full and split thickness skin grafts, temporising matrices and scaffolds, and composite cultured skin products. Notable developments include next generation skin substitutes to replace split thickness skin autografts and next generation gene editing coupled with cell therapies to treat genodermatoses. Further refinements are predicted with the advent of bioprinting technologies, and newly defined biomaterials and autologous cell sources that can be engineered to more accurately replicate human skin architecture, function and cosmesis. These advances will undoubtedly improve quality of life for patients with extensive burns and difficult to heal wounds.

Delayed post mastectomy breast reconstructions with allogeneic acellular dermal matrix prepared by a new decellularizationmethod

Acellular dermal matrix (ADM) is a tissue graft of allogeneic origin from post-mortem tissue donors prepared by an innovative decellularization process. The newly developed non-toxic and low cost decellularization process of cadaver origin dermis included ADM in breast reconstruction procedures proved to help coverage of the lower-pole of breast expanders or implants. As the results have shown, it did help to eliminate autologous dermis donor site morbidity along with shortening the operation time by avoiding elevation of additional muscle or fascia during the operation. Main aims of this article include histology evaluation of allogeneic acellular dermal matrix prepared by a new decellularization method and presentation of clinical results of its use. A total of 22 patients underwent 26 ADM based breast reconstructions. The mean patient's follow up was 12.6 months. Average total size of ADM used for one breast was 273 cm². Post-operative complications occurred in 3 patients including one expander infection, one expander extrusion and one expander pocket disfiguration. Microscopic analysis of tissue samples has confirmed incorporation of the acellular dermal matrices into the surrounding connective tissue without any noticeable immune reaction. In a majority of the ADM samples we found pseudocapsullar formation on implant side of samples without acute or chronic inflammatory cells. The use of ADM prepared by new preparation method in expansive post mastectomy breast reconstruction was associated by a relatively low complication rate resulting in good outcomes.

A randomized clinical trial of a human acellular dermal matrix demonstrated superior healing rates for chronic diabetic foot ulcers over conventional care and an active acellular dermal matrix comparator

This study compared the efficacy and safety of a human acellular dermal matrix (ADM), D-ADM, with a conventional care arm and an active comparator human ADM arm, GJ-ADM, for the treatment of chronic diabetic foot ulcers. The study design was a prospective, randomized controlled trial that enrolled 168 diabetic foot ulcer subjects in 13 centers across 9 states. Subjects in the ADM arms received one application but could receive one additional application of ADM if deemed necessary. Screen failures and early withdrawals left 53 subjects in the D-ADM arm, 56 in the conventional care arm, and 23 in the GJ-ADM arm (2:2:1 ratio). Subjects were followed through 24 weeks with major endpoints at Weeks 12, 16, and 24. Single application D-ADM subjects showed significantly greater wound closure rates than conventional care at all three endpoints while all applications D-ADM displayed a significantly higher healing rate than conventional care at Week 16 and Week 24. GJ-ADM did not show a significantly greater healing rate over conventional care at any of these time points. A blinded, third party adjudicator analyzed healing at Week 12 and expressed "strong" agreement (κ = 0.837). Closed ulcers in the single application D-ADM arm remained healed at a significantly greater rate than the conventional care arm at 4 weeks posttermination (100% vs. 86.7%; p = 0.0435). There was no significant difference between GJ-ADM and conventional care for healed wounds remaining closed. Single application D-ADM demonstrated significantly greater average percent wound area reduction than conventional care for Weeks 2-24 while single application GJ-ADM showed significantly greater wound area reduction over conventional care for Weeks 4-6, 9, and 11-12. D-ADM demonstrated significantly greater wound healing, larger wound area reduction, and a better capability of keeping healed wounds closed than conventional care in the treatment of chronic DFUs.

Biological incorporation of human acellular dermal matrix used in Achilles tendon repair

Human acellular dermal matrices (ADMs) are used successfully in a variety of procedures, including sports medicine related, wound repair, and breast reconstructions, but the mechanism of repair is still not fully understood. An opportunity to explore this mechanism presented itself when a patient experienced a rerupture of the native tendon due to a fall that occurred 2 months after undergoing an Achilles tendon repair using Matracell treated ADM. The ADM was removed and an extensive histology analysis was performed on the tissue. Additionally, a literature review was conducted to determine the mechanism of ADM integration into the tendon structure and explore if differences in this mechanism exist for different types of human ADMS. The histology analysis demonstrated that the healing process during a tendon reconstruction procedure is similar to that of wound healing. Furthermore, the literature review showed that differences exist in the mechanism for integration among various human ADMs and that these differences may be due to variances in the methods and technologies that manufactures use to process human ADMs.

Use of Costal Perichondrium as an Interpositional Graft for Septal Perforation Closure

Importance

Closure of septal perforations remains a technically difficult procedure to perform.

Objective

To assess the use of costal perichondrium as an interpositional graft to enhance closure of septal perforations using bilateral mucosal flaps and the effectiveness of the procedure.

Design, Setting, and Participants

This case series included all 51 consecutive patients presenting with septal perforations from January 1, 2006, to August 31, 2014, at a single institution. Mean (SD) follow-up was 19 (18) months. Patients with subtotal perforations did not have their perforations closed but underwent rhinoplasty with improved form and function. All patients underwent evaluation for changes in postoperative symptoms.

Interventions

Bipedicled mucoperichondrial flaps with placement of costal perichondrium between the repaired flaps.

Main Outcomes and Measures

Success rate of septal perforation closures and the clinical impact of the success of closure as experienced by the patient using the validated Nasal Obstruction Symptom Evaluation (NOSE) questionnaire (range, 0-20; higher scores indicate greater obstruction).

Results

Of the 51 patients (14 male; 37 female; median age, 42.6 [range, 17-69] years), 44 underwent attempted closure of the perforation at the time of the procedure. Closure was successful in 42 of the 44 patients (95%).Two patients had persistent perforations, one of which was subsequently closed in a secondary procedure. Twenty-six of 51 patients with septal perforations completed preoperative and postoperative NOSE questionnaires. The mean (SD) preoperative and postoperative NOSE scores were 12.6 (4.2; range, 6-20) and 3.4 (3.8; range, 0-12), respectively (P < .001). A mean (SD) improvement of 9.0 (3.9) points in the NOSE score was observed from patients after closure of their septal perforation, and 10 patients reported no symptoms (NOSE score, 0).

Conclusions and Relevance

Costal perichondrium is an effective interpositional graft to be used in conjunction with the bilateral mucoperichondrial flaps for closure of septal perforations. Costal perichondrium may be used to aid in closure rates of septal perforations.

Level of Evidence

4.

Retrospective observational analysis of the use of an architecturally unique dermal regeneration template (Derma Pure®) for the treatment of hard-to-heal wounds

The purpose of this analysis was to evaluate the use of DermaPure, a decellularised human skin allograft, in the treatment of a variety of challenging wounds. This retrospective observational analysis reviewed a total of 37 patients from 29 different wound clinics across the USA. Each patient received one application of DermaPure which was followed until complete closure. A statistical analysis was performed with the end point being complete healing. All wounds on average, had a duration of 56 weeks and healed in an average time of 10·58 weeks. Individual wound categories included diabetic foot ulcers, which healed in 8·21 weeks; venous leg ulcers, which healed in 11·29 weeks; and surgical/traumatic wounds, which healed in 11·8 weeks.

Artificial dermal templates: A comparative study of NovoSorb™ Biodegradable Temporising Matrix (BTM) and Integra(®) Dermal Regeneration Template (DRT)

BACKGROUND

Artificial dermal templates play an important role in physiologic wound closure after injury. In addition to contributing to stable, durable and flexible wound closure, they provide a scaffold for tissue repair. Several dermal templates are commercially available, with animal-derived Integra(®) dermal regeneration template perhaps the most widely used. NovoSorb™ Biodegradable Temporising Matrix (BTM) is a fully synthetic alternative that eliminates any risk of cross-species residual antigenicity. In this study, we aimed to compare early response after application of NovoSorb™ BTM with Integra(®) in terms of temporary wound closure, host cell infiltration, neovascularisation and collagen deposition in a mouse model.

METHODS

Twenty athymic nude mice received full-thickness skin excision followed by grafting of the dermal template (n=10 NovoSorb™ BTM, n=10 Integra(®)), with the grafts excised and assessed after two weeks.

RESULTS

All twenty mice achieved temporary wound closure with no evidence of wound contracture. Microscopically, all twenty grafts became infiltrated with host cells along the entire length of the template, with NovoSorb™ BTM demonstrating a particular abundance of host inflammatory cells. Evidence of new collagen deposition and neovascularisation was observed in both templates, with NovoSorb™ BTM demonstrating a more extensive vascular network at this time point. However, a greater inflammatory response was also observed in the NovoSorb™ BTM grafts at this time point.

CONCLUSIONS

In this study, NovoSorb™ BTM demonstrates favourable properties as a dermal template, but further investigation is required to assess the significance of the differing inflammatory and vascular response to its implantation compared with Integra(®).

DermACELL: Human Acellular Dermal Matrix Allograft A Case Report

Diabetes often causes ulcers on the feet of diabetic patients. A 56-year-old, insulin-dependent, diabetic woman presented to the wound care center with a Wagner grade 3 ulcer of the right heel. She reported a 3-week history of ulceration with moderate drainage and odor and had a history of ulceration and osteomyelitis in the contralateral limb. Rigorous wound care, including hospitalization; surgical incision and drainage; intravenous antibiotic drug therapy; vacuum-assisted therapy; and a new room temperature, sterile, human acellular dermal matrix graft were used to heal the wound, save her limb, and restore her activities of daily living. This case presentation involves alternative treatment of a diabetic foot ulcer with this new acellular dermal matrix, DermACELL.

The Burn Wound Microenvironment

Significance: While the survival rate of the severely burned patient has improved significantly, relatively little progress has been made in treatment or prevention of burn-induced long-term sequelae, such as contraction and fibrosis. Recent Advances: Our knowledge of the molecular pathways involved in burn wounds has increased dramatically, and technological advances now allow large-scale genomic studies, providing a global view of wound healing processes. Critical Issues: Translating findings from a large number of in vitro and preclinical animal studies into clinical practice represents a gap in our understanding, and the failures of a number of clinical trials suggest that targeting single pathways or cytokines may not be the best approach. Significant opportunities for improvement exist. Future Directions: Study of the underlying molecular influences of burn wound healing progression will undoubtedly continue as an active research focus. Increasing our knowledge of these processes will identify additional therapeutic targets, supporting informed clinical studies that translate into clinical relevance and practice.

Fistula tract curettage and the use of biological dermal plugs improve high transsphincteric fistula healing in an animal model

PURPOSE

The treatment of high transsphincteric fistula is a complex procedure, which may be associated with the risk of recurrence and fecal incontinence. In this study, we used an animal model to compare different types of sphincter-preserving treatments for transsphincteric fistula.

METHODS

Sixteen female New Zealand rabbits, weighing 2.8-4.8 kg underwent a surgical creation of high transsphincteric fistula. After 6 weeks, magnetic resonance imaging (MRI) was performed in order to confirm fistula formation and measure the fistula diameter. The rabbits were divided into three groups. Group 1 received no plug treatment (control). Autologous dermal graft and acellular dermal matrix were used as a plug in groups 2 and 3, respectively. Five weeks after treatment, fistula tract healing was determined by measuring the largest fistula diameter with MRI. All rabbits were euthanized and the anorectum excised en bloc for histopathological examination.

RESULTS

According to the MRI findings, all groups showed significant healing after the treatment (p < 0.05). The healing rate of fistula diameters after treatment was 40, 66, and 29% in the control, dermal graft, and acellular dermal matrix groups, respectively. In terms of negative healing parameters such as neutrophil, eosinophil, lymphocyte, and plasmocyte accumulation, dermal graft and acellular dermal matrix groups showed significantly lower results than those in the control group (p < 0.05).

CONCLUSION

According to MRI and histopathological results, fistula tract curettage and fistula orifice closure improved transsphincteric anal fistula healing. Additionally, in this study, plug treatment favoring autologous dermal graft resulted in better healing.

Challenges in the Treatment of Chronic Wounds

Significance: Chronic wounds include, but are not limited, to diabetic foot ulcers, venous leg ulcers, and pressure ulcers. They are a challenge to wound care professionals and consume a great deal of healthcare resources around the globe. This review discusses the pathophysiology of complex chronic wounds and the means and modalities currently available to achieve healing in such patients. Recent Advances: Although often difficult to treat, an understanding of the underlying pathophysiology and specific attention toward managing these perturbations can often lead to successful healing. Critical Issues: Overcoming the factors that contribute to delayed healing are key components of a comprehensive approach to wound care and present the primary challenges to the treatment of chronic wounds. When wounds fail to achieve sufficient healing after 4 weeks of standard care, reassessment of underlying pathology and consideration of the need for advanced therapeutic agents should be undertaken. However, selection of an appropriate therapy is often not evidence based. Future Directions: Basic tenets of care need to be routinely followed, and a systematic evaluation of patients and their wounds will also facilitate appropriate care. Underlying pathologies, which result in the failure of these wounds to heal, differ among various types of chronic wounds. A better understanding of the differences between various types of chronic wounds at the molecular and cellular levels should improve our treatment approaches, leading to better healing rates, and facilitate the development of new more effective therapies. More evidence for the efficacy of current and future advanced wound therapies is required for their appropriate use.

Development and preparation of a low-immunogenicity porcine dermal scaffold and its biocompatibility assessment

Acellular dermal matrix (ADM) has been widely used in repair and reconstruction of tissue defect. Therapeutic effect of porcine ADM (PADM) is inferior to that of human ADM (HADM). Relatively high immunogenicity and the resulting strong inflammatory response are major issue in application of PADM. We therefore treated reticular layer PADM (Rl-PADM) with matrix metalloproteinase-7 (MMP-7) and obtained a low-immunogenicity porcine dermal scaffold (LIPDS). Highly immunogenic components, tissue structure, cytocompatibility, and postgrafting histological changes of LIPDS were further investigated. Compared with Rl-PADM, LIPDS showed that the epithelial root sheath, cell debris, laminin, and type IV collagen were almost entirely removed, the structure remained normal, and the interfibrous space was relatively enlarged. Cytocompatibility of LIPDS was similar to that of HADM but superior to Rl-PADM. With regard to the extent of tissue ingrowth in terms of host fibroblasts infiltration and vascularization, LIPDS exhibited clear advantages over Rl-PADM after they had been subcutaneously transplanted in a rat model. In addition, no excessive inflammatory response was observed in LIPDS group up to 28 days postgraft, and the morphosis of collagenous fibers kept essentially normal. However, there were stronger inflammatory response and obvious collagen spallation in Rl-PADM group. The processes of integration and remodeling after the LIPDS grafting were similar to those of a normal wound healing response. The LIPDS graft was vascularized at a relatively high speed. Thus, as an implantable scaffold material, LIPDS is a superior template for guiding tissue regeneration and remodeling.

Comparative experimental study of wound healing in mice: Pelnac versus Integra

Strategies for skin regeneration have been developed to provide effective treatment for cutaneous wounds and disease. Dermal substitutes have been used to cover the lesion to facilitate cell colonization, thereby promoting dermal regeneration. However, very little is known about Pelnac matrix especially at histological level. Therefore, the present work carried out an experimental in vivo comparative analysis between Pelnac and Integra, the most used dermal templates, in a mouse model of full-thickness skin wounds. Histological sections performed at the 3^rd, 6^th and 9^th days after surgery were analyzed with regard to inflammatory response and vascularization. Both templates were completely incorporated in all animals at the end of the analyzed period. Pelnac-treated animals displayed reduced granulation tissue during the first 6 days of treatment compared to the animals treated with Integra at the same time period. The number of inflammatory cells (neutrophils) was similar in both groups during the period, significantly reducing at the end of inflammatory phase (9^th day of treatment) consistent with the progression of healing process. In addition, the density of blood vessels was also statistically similar in both matrices. Therefore, the two dermal templates displayed comparable biological behavior in tissue repair. It is noteworthy that this is the first experimental study comparing Pelnac and Integra dermal templates with focus on full-thickness skin wounds.

Wound healing: an update

Wounds, both chronic and acute, continue to be a tremendous socioeconomic burden. As such, technologies drawn from many disciplines within science and engineering are constantly being incorporated into innovative wound healing therapies. While many of these therapies are experimental, they have resulted in new insights into the pathophysiology of wound healing, and in turn the development of more specialized treatments for both normal and abnormal wound healing states. Herein, we review some of the emerging technologies that are currently being developed to aid and improve wound healing after cutaneous injury.

Decellularization of human dermis using non-denaturing anionic detergent and endonuclease: a review

Decellularized human dermis has been used for a number of clinical applications including wound healing, soft tissue reconstruction, and sports medicine procedures. A variety of methods exist to prepare this useful class of biomaterial. Here, we describe a decellularization technology (MatrACELL^®) utilizing a non-denaturing anionic detergent, N-Lauroyl sarcosinate, and endonuclease, which was developed to remove potentially immunogenic material while retaining biomechanical properties. Effective decellularization was demonstrated by a residual DNA content of ≤4 ng/mg of wet weight which represented >97 % DNA removal compared to unprocessed dermis. Two millimeter thick MatrACELL processed human acellular dermal matrix (MH-ADM) exhibited average ultimate tensile load to failure of 635.4 ± 199.9 N and average suture retention strength of 134.9 ± 55.1 N. Using an in vivo mouse skin excisional model, MH-ADM was shown to be biocompatible and capable of supporting cellular and vascular in-growth. Finally, clinical studies of MH-ADM in variety of applications suggest it can be an appropriate scaffold for wound healing, soft tissue reconstruction, and soft tissue augmentation.

DermACELL: a novel and biocompatible acellular dermal matrix in tissue expander and implant-based breast reconstruction

BACKGROUND

Acellular dermal matrices present a new alternative to supporting expanders and implants for breast reconstruction in breast cancer patients following mastectomy. However, some studies have suggested that acellular dermal matrix may increase the complication rates in certain clinical settings. DermACELL acellular dermal matrix offers advanced processing in order to attempt to decrease bio-intolerance and complications.

METHODS

Ten consecutive patients that presented for breast reconstruction and were candidates for tissue expanders underwent the procedure with the use of an acellular dermal matrix. The patients underwent postoperative expansion/adjuvant cancer therapy, then tissue expander exchange for permanent silicone breast prostheses. Patients were followed through the postoperative course to assess complication outcomes. Histologic evaluation of host integration into the dermal matrix was also assessed.

RESULTS

Of the ten patients, eight completed reconstruction while two patients failed reconstruction. The failures were related to chronic seromas and infection. Histology analysis confirms rapid integration of mesenchymal cells into the matrix compared to other acellular dermal matrices.

CONCLUSIONS

Based on our observations, DermACELL is an appropriate adjunct to reconstruction with expanders. Histological analysis of vascularization and recellularization support the ready incorporation of DermACELL into host tissue. Level of Evidence: Level IV, therapeutic study.

Clinical Outcomes for Breast Cancer Patients Undergoing Mastectomy and Reconstruction with Use of DermACELL, a Sterile, Room Temperature Acellular Dermal Matrix

Background. Decellularized human skin has been used in a variety of medical applications, primarily involving soft tissue reconstruction, wound healing, and tendon augmentation. Theoretically, decellularization removes potentially immunogenic material and provides a clean scaffold for cellular and vascular in growth. The use of acellular dermal matrix in two-stage postmastectomy breast reconstruction is described. Methods. Ten consecutive breast cancer patients were treated with mastectomies and immediate reconstruction from August to November 2011. There were 8 bilateral and 1 unilateral mastectomies for a total of 17 breasts, with one exclusion for chronic tobacco use. Reconstruction included the use of a new 6 × 16 cm sterile, room temperature acellular dermal matrix patch (DermACELL) soaked in a cefazolin bath. Results. Of the 17 breasts, 15 reconstructions were completed; 14 of them with expander to implant sequence and acellular dermal matrix. Histological analysis of biopsies obtained during trimming of the matrix at the second stage appeared nonremarkable with evidence of normal healing, cellularity, and vascular infiltration. Conclusion. Postoperative observations showed that this cellular dermal matrix appears to be an appropriate adjunct to reconstruction with expanders. This acellular dermal matrix appeared to work well with all patients, even those receiving postoperative chemotherapy, postoperative radiation, prednisone, or warfarin sodium.

Early kinetics of integration of collagen-glycosaminoglycan regenerative scaffolds in a diabetic mouse model

BACKGROUND

Collagen-glycosaminoglycan scaffolds, originally designed to treat severe burns, are now commonly used in patients with complex wounds associated with diabetes mellitus. In this study, the authors investigated how the thickness of the scaffold would affect cellular integration with the diabetic host and whether this can be accelerated using subatmospheric pressure wound therapy devices.

METHODS

Collagen-glycosaminoglycan scaffolds, 500 to 2000-μm thick, were applied to dorsal wounds in genetically diabetic mice. In addition, 1000-μm collagen-glycosaminoglycan scaffolds with and without silicone were treated with a subatmospheric pressure device (-125 mmHg). On days 5 and 10, cellular and vascular integration of tissues was studied by histology, immunohistochemistry, corrosion casting, and qRT-polymerase chain reaction.

RESULTS

Cells and vessels from the wound surface populated the scaffold to form layers with varying cellular density. Areas of high cell density and proliferation were noted at the bottom of the scaffold. Increasing the thickness of the scaffold did not affect the extent of cellular ingrowth, so that thicker scaffolds had a thicker residual acellular layer on the surface. The thickness of cellular ingrowth was stable between days 5 and 10, whereas vessels seen in the scaffolds on day 10 were not yet present on day 5. Subatmospheric pressure devices applied to silicone-covered collagen-glycosaminoglycan scaffolds minimized the granulation tissue formation beneath the scaffold, which enhanced vessel ingrowth.

CONCLUSIONS

The early kinetics of cellular integration into collagen-glycosaminoglycan scaffolds is independent of scaffold thickness in a diabetic wound model. Scaffold adherence to the wound and integration can be improved using a subatmospheric pressure device.