Matrix Graft Research Articles

A Comparative Analysis of Outcomes of Pterygium Surgery with or without Collagen Matrix Implantation

Background: Pterygium is a common disorder in many parts of the world, with reported prevalence rates ranging from 0.3 to 29%. Epidemiological studies have proposed an association with chronic exposure to sunlight and an increased geographical prevalence within a peri-equatorial ‘pterygium belt’ region (1). Pterygium excision is often combined with various adjunctive measures to prevent its recurrence, however recurrenece is still the most common post-surgical complication. Numerous techniques have been attempted to reduce localized fibrovascular activity and the overall rate of recurrence; these include, β-irradiation, conjunctival and limbal auto-grafting, antimitotic drugs and amniotic membrane transplantation (2). In recent years, a novel bioengineered product has been advocated for preventing recurrence and has shown promising outcomes in animal models This study was conducted to compare the effect of collagen matrix implant with conjunctival autograft following pterygium surgery (treatment group) with only conjunctival autograft following pterygium surgery (control group). Methods: Following informed consent, sixty eyes of 60 patients (females = 23, males =37, aged 23–67 years) were randomly allocated into two equal groups. Pterygia of all patients were excised and conjunctival autograft was done. However, for patients in the treatment group a 1×3 mm collagen matrix graft (Ologen) was implanted subconjunctivally under the graft. Patients were followed up for six months. The parameters studied were patient comfort, foreign body sensation, dellen formation, pterygium recurrence and time for absorption of the collagen matrix. Results: Results revealed that no eyes in the control group and one eye in the intervention group developed recurrence; dellen formation not was observed in any patient in both groups. Patient comfort and foreign body sensation did not differ significantly in both groups. Three eyes in treatment group developed a tenon’s cyst. In 12 out of 30 eyes, the collagen matrix was not absorbed at six months post surgery. Conclusion: In conclusion, the use of biodegradable collagen matrix implants (Ologen) following pterygium excision did not seem to be associated with a lower risk of recurrence. Moreover, tenon’s cyst formation and persistence of the matrix subconjunctivally was observed. Further studies with adequate sample size are recommended for more comprehensive conclusion.

The Use of Vascular Endothelial Growth Factor with Silk Fibroin Scaffolds and Bladder Acellular Matrix Grafts to Support Bladder Reconstruction in Rabbit Model

The Use of Vascular Endothelial Growth Factor with Silk Fibroin Scaffolds and Bladder Acellular Matrix Grafts to Support Bladder Reconstruction in Rabbit Model

A prospective, multicenter study to evaluate clinical and radiographic outcomes in primary rotator cuff repair reinforced with a xenograft dermal matrix

Minimal information is currently available on the outcome of rotator cuff repair reinforced with an extracellular matrix (ECM) graft. Therefore, the purpose of this study was to determine the clinical and radiographic outcome of repair of large rotator cuff tears with ECM graft reinforcement. This was a prospective study of 61 shoulders with large repairable rotator cuff tears (3 to 5 cm). The rotator cuff tears were surgically repaired and reinforced with a xenograft ECM graft. The average patient age was 56 years (range, 40-69 years). The average tear size was 3.8 cm. Follow-up was obtained at 6, 12, and 24 months in 58, 54, and 50 of the 61 patients, respectively. Functional outcome scores, isometric muscle strength, and active range of motion were significantly improved compared with baseline. Magnetic resonance imaging at 12 months showed retorn rotator cuff repairs in 33.9% of shoulders, using the criteria of a tear of at least 1 cm, and tears in 14.5% of the shoulders using the criteria of retear >80% of the original tear size. Three patients underwent surgical revision. Complications included 1 deep infection. Repair of large rotator cuff tears structurally reinforced with xenograft ECM resulted in improved functional outcomes scores and strength. Adverse events were uncommon, and the rate of revision surgery was low.

Mineralized Plasmatic Matrix versus Bone Graft Alone in Augmentation of Bone Cavities

Mineralized Plasmatic Matrix versus Bone Graft Alone in Augmentation of Bone Cavities

15: Transvaginal excision of eroded sacrocolpopexy mesh into bladder with extracellular matrix graft augmentation

15: Transvaginal excision of eroded sacrocolpopexy mesh into bladder with extracellular matrix graft augmentation

Biocellulose as Dural Substitute in Skull Base Endoscopic Surgery and Reconstruction

Introduction: Skull base (SB) reconstruction with a multilayer vascularized technique has proven to promote the best surgical outcomes, after endoscopic endonasal approaches (EEAs). The technique includes the use of a dural substitute as one of the layers, providing appropriate separation of the neurovascular tissue from the sinonasal cavity. Collagen matrix grafts are largely used in SB reconstructions, however the high costs of the material turn it inaccessible to many Neurosurgical centers in developing countries. Fascia lata is frequently used as an option, but its harvesting raises concerns regarding increasing of the total surgical time, morbidity of a second surgical site and local pain. Lyophilized biocellulose have been studied in several fields of Odontology and Medicine as human tissue substitute, including Neurosurgery. Studies showed its safety as dural substitute for convexity dural lesions, as a watertight, suture resistant and not brain adherent membrane.

279 Bladder acellular matrix grafts seeded with adipose-derived stem cells and incubated intraperitoneally promote the regeneration of bladder smooth muscle in a rat model of bladder augmentation

279 Bladder acellular matrix grafts seeded with adipose-derived stem cells and incubated intraperitoneally promote the regeneration of bladder smooth muscle in a rat model of bladder augmentation

Coronally advanced flap with or without porcine collagen matrix for root coverage: a randomized clinical trial.

The objective of this study is to clinically evaluate the outcomes following treatment of single gingival recessions with either coronally advanced flap technique (CAF) alone or combined with a porcine collagen matrix graft (CM). This is a randomized parallel design clinical trial, including forty patients with single Miller Class I or II gingival recession, with a depth≥2mm and located at upper canines or premolars. The patients were randomly assigned to receive either CAF or CAF+CM. The primary outcome variable was gingival recession reduction (Rec Red). Baseline recession depth was 3.14±0.51mm for CAF group and 3.16±0.65mm for CAF+CM group (p>0.05). Both groups showed significant Rec Red (p<0.05), up to 6months. Rec Red for CAF+CM was 2.41±0.73mm and was 2.25±0.50mm for CAF alone (p>0.05). Root coverage was 77.2% in the CAF+CM group and 72.1% in the CAF group (p>0.05). Complete root coverage (CRC) was found in 40% of the cases in the CAF+CM group and in 35% of the sites treated with CAF. Keratinized tissue thickness (KTT) was 0.26mm higher in CAF+CM group (p<0.05). It can be concluded that CAF+CM does not provide a superior recession reduction when compared to CAF; however, it may offer a small gain in KTT after 6months. CAF+CM can be suggested as a valid therapeutic option to achieve root coverage and some increase in soft tissue thickness after 6months.

Bladder Acellular Matrix Grafts Seeded with Adipose-Derived Stem Cells and Incubated Intraperitoneally Promote the Regeneration of Bladder Smooth Muscle and Nerve in a Rat Model of Bladder Augmentation.

The objective of this study was to investigate the feasibility of bladder acellular matrix grafts (BAMGs) seeded with adipose-derived stem cells (ASCs) followed by intraperitoneal incubation for bladder reconstruction in a rat model of bladder augmentation, and to explore the underlying mechanism. Autologous CM-DiI-labeled ASC-seeded (experimental group) and unseeded (control group) BAMGs were incubated in the peritoneum of male rats for 2 weeks and then harvested for bladder augmentation. Histological analysis of the incubated BAMGs revealed numerous cells growing in homogeneous collagen bundles in both groups. In the control BAMGs, these cells were mesenchyme derived, while in the ASC-seeded BAMGs, myofibroblasts and mesothelial cells were found inside and on the surface of the scaffold, respectively. Immunofluorescence analysis demonstrated that some of the myofibroblasts were transdifferentiated from the ASCs after 2 weeks of intraperitoneal incubation. The greater bladder capacity was found in the experimental group than the control group both 4 and 14 weeks postoperatively. Histological analysis revealed that the entire urothelium regenerated well both in the experimental group and the control group without significant difference 4 weeks and 14 weeks postoperatively. From the quantitative data of immunohistochemical and immunofluorescence staining, the smooth muscle cells (SMCs) regenerated significantly better in the experimental group than the control group both 4 weeks and 14 weeks postoperatively. Also significantly more nerve cells were found in the experimental group 14 weeks postoperatively. At 4 weeks postoperatively, the immunofluorescence double staining revealed that some SMCs in the BAMG were transdifferentiated from the implanted ASCs, but no CM-DiI labeling of ASCs was detected 14 weeks postoperatively. Taken together, our results demonstrate that ASC-seeded and peritoneally incubated BAMGs promote not only the morphological regeneration of the bladder smooth muscle and nerve, but also the bladder capacity, which indicates their potential for bladder regeneration.

Efficacy of platelet rich fibrin in the treatment of human intrabony defects with or without bone graft: A randomized controlled trial.

Aim:To evaluate the efficacy of platelet rich fibrin (PRF) with or without bone graft [demineralized bone matrix (DBM) graft] in the treatment of intrabony defects based on clinical and radiographic parameters.Materials and Methods:Thirty six intrabony defects in 36 patients were randomly divided into three different groups and were treated with group A (PRF with DBM) or group B (PRF alone) or group C [open flap debridement (OFD)]. Clinical parameters such as plaque index (PI), gingival index (GI), probing depth (PD), relative attachment level (RAL), and gingival recession (GR) were assessed at baseline and 9 months postoperatively; radiographic parameters such as linear bone growth (LBG) and percentage in bone fill (%BF) were calculated by using the image analysis software. Comparisons of groups were analyzed using Kruskal–Wallis analysis of variance test. Pair-wise comparison of groups was done by Mann-Whitney U test.Results:Mean PD reduction and RAL gain were greater in group A (4.25 ± 1.48, 3.92 ± 0.90) and group B (3.82 ± 0.75, 3.27 ± 0.65) than control (3.00 ± 1.21, 2.25 ± 0.62). Furthermore, statistically significant improvement in LBG and %BF was found in group A (3.47 ± 0.53, 61.53 ± 4.54) compared to group B (2.55 ± 0.61, 49.60 ± 14.08) and group C (1.21 ± 0.80, 24.69 ± 15.59).Conclusions:The study demonstrated that PRF improves clinical and radiological parameters compared to OFD alone in intrabony defects. Addition of DBM enhances the effects of PRF in RAL gain and radiographic defect fill.

Management of gingival recession with acellular dermal matrix graft: A clinical study.

Aims and Objectives:Obtaining root coverage has become an important part of periodontal therapy. The aims of this studyare to evaluate the clinical efficacy of acellular dermal matrix graft in the coverage of denuded roots and also to examine the change in the width of keratinized gingiva.Materials and Methods:A total of 20 sites with more than or equal to 2 mm of recession depth were taken into the study, for treatment with acellular dermal matrix graft. The clinical parameters such as recession depth, recession width, width of keratinized gingiva, probing pocket depth (PD), and clinical attachment level (CAL) were measured at the baseline, 8th week, and at the end of the study (16th week). The defects were treated with a coronally positioned pedicle graft combined with acellular dermal matrix graft.Results:Out of 20 sites treated with acellular dermal matrix graft, seven sites showed complete root coverage (100%), and the mean root coverage obtained was 73.39%. There was a statistically significant reduction in recession depth, recession width, and probing PD. There was also a statistically significant increase in width of keratinized gingiva and also gain in CAL. The postoperative results were both clinically and statistically significant (P < 0.0001).Conclusion:The results of this study were esthetically acceptable to the patients and clinically acceptable in all cases. From this study, it may be concluded that acellular dermal matrix graft is an excellent substitute for autogenous graft in coverage of denuded roots.

Parastomal hernia repair with urinary bladder matrix grafts: A case series

Introduction: Parastomal hernias are a common complication of ileostomy and colostomy creation. Most are managed non-operatively, but some require surgery because of progressive symptoms and obstruction. Porcine urinary bladder matrix (UBM), utilized in many hernia applications, serves as an effective biologically-derived extracellular matrix scaffold and facilitates a favorable remodeling response with restoration of site-appropriate tissue. Case Series: Herein, eight cases are presented which describe four different techniques of parastomal hernia repair utilizing porcine UBM. In four cases, repair was performed through open laparotomy; the remaining four were performed laparoscopically. All repairs were reinforced with porcine UBM. Median duration of follow-up is 23 months. Conclusion: Surgeons may safely employ open and laparoscopic techniques for successful repair of parastomal hernias. In this series of eight cases, repairs with porcine UBM devices have proven durable at two years of follow-up and may serve as an alternative to synthetic mesh. (This page in not part of the published article.) International Journal of Case Reports and Images, Vol. 7 No. 2, February 2016. ISSN – [0976-3198] Int J Case Rep Images 2016;7(2):85–91. www.ijcasereportsandimages.com Sasse et al. 85 CASE REPORT OPEN ACCESS Parastomal hernia repair with urinary bladder matrix grafts: A case series Kent C. Sasse, David L. Warner, Ellen Ackerman, Jared Brandt

Decellularized bone matrix grafts for calvaria regeneration

Decellularization is a promising new method to prepare natural matrices for tissue regeneration. Successful decellularization has been reported using various tissues including skin, tendon, and cartilage, though studies using hard tissue such as bone are lacking. In this study, we aimed to define the optimal experimental parameters to decellularize natural bone matrix using 0.5% sodium dodecyl sulfate and 0.1% NH4OH. Then, the effects of decellularized bone matrix on rat mesenchymal stem cell proliferation, osteogenic gene expression, and osteogenic differentiations in a two-dimensional culture system were investigated. Decellularized bone was also evaluated with regard to cytotoxicity, biochemical, and mechanical characteristics in vitro. Evidence of complete decellularization was shown through hematoxylin and eosin staining and DNA measurements. Decellularized bone matrix displayed a cytocompatible property, conserved structure, mechanical strength, and mineral content comparable to natural bone. To study new bone formation, implantation of decellularized bone matrix particles seeded with rat mesenchymal stem cells was conducted using an orthotopic in vivo model. After 3 months post-implantation into a critical-sized defect in rat calvaria, new bone was formed around decellularized bone matrix particles and also merged with new bone between decellularized bone matrix particles. New bone formation was analyzed with micro computed tomography, mineral apposition rate, and histomorphometry. Decellularized bone matrix stimulated mesenchymal stem cell proliferation and osteogenic differentiation in vitro and in vivo, achieving effective bone regeneration and thereby serving as a promising biological bone graft.

Tunnel technique versus coronally advanced flap with acellular dermal matrix graft in the treatment of multiple gingival recessions.

The aim of this randomized controlled clinical study was to evaluate the outcomes of acellular dermal matrix (ADM) graft in combination with tunnel technique (TUN) on root coverage, aesthetics, and patient satisfaction and to compare with coronally advanced flap (CAF)+ADM in the treatment of multiple gingival recessions. A total of 20 patients with 58 Miller Class I multiple recessions ≥3mm were included and divided into TUN+ADM and CAF+ADM groups. At baseline and 12months, probing depth (PD), clinical attachment level (CAL), recession height (RH) and width (RW), keratinized tissue height (KT), gingival thickness, and complete and mean root coverage (CRC, MRC) were evaluated. Patient satisfaction and root coverage aesthetic scores (RES) were also assessed. Mean root coverage was 75.72% in TUN+ADM and 93.81% in CAF+ADM. Intragroup comparisons revealed significant differences at 12months for all parameters in both groups (p<0.05). Intergroup differences were found to be statistically significant for RH and RW reduction, KT increase, CAL gain, MRC, CRC, and RES in favour of CAF+ADM group (p<0.05). Both techniques were effective in root coverage of multiple recessions; however, better clinical results were achieved with CAF and ADM combination.

Peroneus Brevis Muscle Flap with the use of INTEGRA® Wound Matrix and Split Thickness Skin Graft in the Treatment of Full Thickness Ulcerations: Case Reports and Technique Guide

One major factor contributing to chronic non-healing ulcerations is the lack of an adequate wound base in which proliferation of the wound can occur. Furthermore, disruption of the soft tissue envelope, either by surgical or non-surgical means, can leave little to no foundation to cover vital underlying structures. For example, post surgical wound dehiscence following open reduction and internal fixation can result in exposed hardware and without viable soft-tissue to cover the exposed hardware, an adequate wound base is incapable of forming. Therefore wound proliferation will not continue.

3D Cone Beam Computed Tomography Volumetric Outcomes of rhBMP-2/Demineralized Bone Matrix vs. Iliac Crest Bone Graft for Alveolar Cleft Reconstruction

3D Cone Beam Computed Tomography Volumetric Outcomes of rhBMP-2/Demineralized Bone Matrix vs. Iliac Crest Bone Graft for Alveolar Cleft Reconstruction

Use of small intestinal submucosal and acellular dermal matrix grafts in giant omphaloceles in neonates and a rabbit abdominal wall defect model

BackgroundThe described surgical strategies for the management of omphalocele include primary closure, staged closure, and delayed closure. A primary repair is not suitable for all giant omphaloceles. We implanted two grafts, small intestinal submucosal (SIS) and acellular dermal matrix (ADM) onto abdominal wall defects in neonates to study the safety and efficacy of SIS and ADM graft techniques for initial closure of giant omphaloceles in infants, and we also implanted these grafts onto abdominal wall defects in an animal model. MethodsTwenty-four patients with giant omphaloceles were divided into two groups (ADM group, 12 patients; SIS group, 12 patients). The operative time, skin healing time postoperatively, and the incidence of skin infections, and abdominal wall hernias were observed. In the rabbit animal model, bilateral full-thickness incisions were made through the rabbit rectus abdominus muscles and a 2×4cm longitudinal whole layer defect was created on either the left or right lateral anterior abdominal wall. A four-layered variant of the SIS graft was used to repair the right abdominal defect; ADM was used to repair the left. Tensile strength was measured using an Instron tensiometer. Electron scanning and light microscopy were used to evaluate neovascularization, collagen deposition, and muscle fibers at 2, 4, 8, and 16weeks postimplantation. ResultsIn the neonatal patients, there was no statistically significant difference between the two groups with respect to operative time, skin healing time postoperatively, the incidence of skin infections, or abdominal wall hernias. In the SIS group, only one patient developed a skin infection, which led to skin necrosis and sloughing. In the ADM group, four patients developed skin infection postoperatively, and the patch was gradually removed. In the animal study, there was no significant difference between the mean breaking strength of ADM versus SIS repairs. Scanning electron and light microscopy showed collagen deposition, increased vascularization, fibroblasts, and muscular regeneration in both SIS and ADM repairs. SEM showed that the SIS graft was absorbed, while ADM was not. Light microscopy showed foreign body macrophages in ADM, but not in the SIS repairs. ConclusionSIS and ADM grafts adequately enhance healing with a low complication rate. Compared with ADM grafts, SIS is absorbable, induces less inflammation, and is more biocompatible, and therefore might be more useful and suitable for closure of abdominal wall defects.

Time-dependent bladder tissue regeneration using bilayer bladder acellular matrix graft-silk fibroin scaffolds in a rat bladder augmentation model

With advances in tissue engineering, various synthetic and natural biomaterials have been widely used in tissue regeneration of the urinary bladder in rat models. However, reconstructive procedures remain insufficient due to the lack of appropriate scaffolding, which should provide a waterproof barrier function and support the needs of various cell types. To address these problems, we have developed a bilayer scaffold comprising a porous network (silk fibroin [SF]) and an underlying natural acellular matrix (bladder acellular matrix graft [BAMG]) and evaluated its feasibility and potential for bladder regeneration in a rat bladder augmentation model. Histological (hematoxylin and eosin and Masson’s trichrome staining) and immunohistochemical analyses demonstrated that the bilayer BAMG-SF scaffold promoted smooth muscle, blood vessel, and nerve regeneration in a time-dependent manner. At 12weeks after implantation, bladders reconstructed with the BAMG-SF matrix displayed superior structural and functional properties without significant local tissue responses or systemic toxicity. These results demonstrated that the bilayer BAMG-SF scaffold may be a promising scaffold with good biocompatibility for bladder regeneration in the rat bladder augmentation model.

Intraperitoneal incubation of bladder acellular matrix grafts improves bladder smooth muscle regeneration via neovascularization

The objective of this study was to investigate whether intraperitoneal incubation improves the regenerative capacity of bladder acellular matrix grafts (BAMGs) in a rat model of bladder augmentation. After 2 weeks of incubation in the peritoneum of male rats, BAMG flaps with vascular pedicles were harvested for autologous bladder augmentation. As the control, BAMGs were directly used for bladder augmentation without intraperitoneal incubation. Histological analyses of the incubated BAMGs demonstrated extensive cell growth and vasculature in homogeneous collagen bundles. The cells were positive for vimentin and negative for α-smooth muscle actin and pan-cytokeratin AE1/AE3. Cystography revealed smoother contours of the augmented bladders in the incubated group at 4 and 12 weeks postoperatively. However, the bladder capacity was not significantly different between the two groups. In both groups, the entire urothelium regenerated well without obvious differences. At both time points, compared with the control group, increased numbers of smooth muscle cells (SMCs) and blood vessels were found in the incubated group. At 12 weeks, the SMCs in the incubated group were more similar to those in the native smooth muscle fiber bundles of the bladder. Taken together, our results demonstrated that BAMGs preincubated in the peritoneum promote the regeneration of bladder smooth muscle via neovascularization in a rat bladder augmentation model.

Transcutaneous Drainage of Gel-Like Substance after Application of Hydrogel Dural Sealant: Report of Two Cases

Study Design Case report. Objective Incidental durotomy (IDT) is a common complication of spinal surgery. The use of collagen matrix graft along with hydrogel dural sealant is a common method of IDT repair. With this method, there have been several reported cases of detrimental dural sealant expansion in the literature. One case study reported an expansion rate greater than 300%; many report neurologic damage. This article reports the clinical course of two patients who developed postoperative transcutaneous drainage of a gel-like substance after the use of a dural sealant, which is a previously unreported complication. Methods The clinical course and treatment outcome of two patients is presented. Results Both patients experienced postoperative transcutaneous drainage of a gel-like substance at the surgical site. Case one began draining this substance on postoperative day 14. This patient required no further intervention, and the drainage ended after 3 mL of a gel-like substance was expressed from his incision while in the clinic. Case two began draining the gel on postoperative day 16. This patient underwent two washout procedures and resolution of the drainage. No infection was ever detected. Conclusions To our knowledge, our patients are the first reported cases of transcutaneous drainage of expanded dural sealant. It is important to take into consideration the unexpected expansion of a dural sealant when using it for the repair of IDT.