ePTFE Implants Research Articles

Label-free multimodal imaging of infected Galleria mellonella larvae

Non-linear imaging modalities have enabled us to obtain unique morpho-chemical insights into the tissue architecture of various biological model organisms in a label-free manner. However, these imaging techniques have so far not been applied to analyze the Galleria mellonella infection model. This study utilizes for the first time the strength of multimodal imaging techniques to explore infection-related changes in the Galleria mellonella larvae due to massive E. faecalis bacterial infection. Multimodal imaging techniques such as fluorescent lifetime imaging (FLIM), coherent anti-Stokes Raman scattering (CARS), two-photon excited fluorescence (TPEF), and second harmonic generation (SHG) were implemented in conjunction with histological HE images to analyze infection-associated tissue damage. The changes in the larvae in response to the infection, such as melanization, vacuolization, nodule formation, and hemocyte infiltration as a defense mechanism of insects against microbial pathogens, were visualized after Enterococcus faecalis was administered. Furthermore, multimodal imaging served for the analysis of implant-associated biofilm infections by visualizing biofilm adherence on medical stainless steel and ePTFE implants within the larvae. Our results suggest that infection-related changes as well as the integrity of the tissue of G. mellonella larvae can be studied with high morphological and chemical contrast in a label-free manner.

A novel bilayered expanded polytetrafluoroethylene glaucoma implant creates a permeable thin capsule independent of aqueous humor exposure.

The purpose of these studies was to evaluate clinical, functional, and histopathological features of glaucoma drainage implants (GDIs) fabricated from novel, custom‐tailored expanded polytetrafluoroethylene (ePTFE). Implants of matching footprints were fabricated from silicone (Control) and novel, bilayered ePTFE. ePTFE implants included: (a) one that inflated with aqueous humor (AH) (High), (b) one that inflated with a lower profile (Low), (c) an uninflated implant not connected to the anterior chamber (Flat), and (d) one filled with material that did not allow AH flow (Filled). All implants were placed in adult New Zealand White rabbits and followed over 1–3 months with clinical exams and intraocular pressure. The permeability of tissue capsules surrounding GDIs was assessed using constant‐flow perfusion with fluoresceinated saline at physiologic flow rates. After sacrifice, quantitative histopathological measures of capsule thickness were compared among devices, along with qualitative assessment of cellular infiltration and inflammation. Capsular thickness was significantly reduced in blebs over ePTFE (61.4 ± 53 μm) versus silicone implants (193.6 ± 53 μm, p = .0086). AH exposure did not significantly alter capsular thickness, as there was no significant difference between High and Filled (50.9 ± 29, p = .34) implants. Capsules around ePTFE implants demonstrated permeability with steady‐state pressure: flow relationships at physiologic flow rates and rapid pressure decay with flow cessation, while pressure in control blebs increased even at low flow rates and showed little decay. Perfused fluorescein dye appeared beyond the plate border only in ePTFE implants. ePTFE implants are associated with thinner, more permeable capsules compared to silicone implants simulating presently used devices.

Polydopamine Functionalization: A Smart and Efficient Way to Improve Host Responses to e-PTFE Implants

Among the different materials used as protheses for the treatment of Congenital Diaphragmatic Hernia, expanded polytetrafluoroethylene (e-PTFE) plays a leading role owing to its mechanical properties as explained in the first part of this review. However, this material is poorly cell adhesive, which is expected for its contact on the abdominal face, but should display specific tissue adhesion on its thoracic exposed faced. A side specific functionalization method is hence required. The deposition of a nanosized polydopamine film on PTFE is known to be possible but immersion of the e-PTFE membrane in an aerated dopamine solution leads to a functionalization not only on both faces of the membrane but also in its porous volume. The fact that polydopamine also forms at the water/air interface has allowed to transfer a polydopamine film on only one face of the e-PTFE membrane. The deposition method and applications of such Janus like membranes are reviewed in the second part of the review.

Paranasal Augmentation Using Multi-Folded Expanded Polytetrafluorethylene (ePTFE) in the East Asian Nose.

Paranasal augmentation has commonly been performed utilizing alloplastic materials such as silicone or porous polyethylene. However, there are problems such as bone absorption, implant migration, and infection risk attributable to intraoral approaches. The authors attempted anterior positioning of the alar crease junction as an adjunct method of rhinoplasty. The authors aimed to determine the long-term results of the intranasal approach for placement of multi-folded expanded polytetrafluorethylene (ePTFE). A retrospective review was conducted of patients who underwent intranasal surgical approach for paranasal augmentation employing multi-folded ePTFE implants in 19 septorhinoplasties who were followed-up for 3 to 10 years. Patient charts were reviewed for demographic information, concomitant operations, and complications. Preoperative and postoperative photographs were utilized to evaluate operative outcomes. The photographs were reformatted to 2-dimensional images employing standard photographic methods. Of the 19 patients treated, 17 were female and 2 were male; ages ranged from 18 to 58 years. All patients reported improvement in their lateral profiles and were pleased at follow-up. There were no major complications, no nerve or vascular supply compromise, and no cases of implant malposition. The average increase in soft tissue outline near the alar crease junction was more than 3.2 mm (P < 0.001), but the alar base did not became wider. Paranasal augmentation with multi-folded ePTFE is a simple, safe, and effective method that can readily improve the lateral profile. In particular, the intranasal approach combined with rhinoplasty can synergistically improve outcomes and lead to greater patient satisfaction.

The Use of Expanded Polytetrafluoroethylene in Short Nose Elongation: Fourteen Years of Clinical Experience.

Short nose elongation is a relatively common rhinoplasty procedure, especially in Asia. The selection of the adequate graft material is challenging. Previous reports have described the application of expanded polytetrafluoroethylene (ePTFE) for dorsal augmentation rhinoplasty, but studies using ePTFE for nose elongation are lacking. We propose ePTFE as an alternative treatment for short noses, describe the technique, and discuss outcomes, patient selection, and complications based on our 14-year experience. From February 2003 to December 2016, 206 patients with varying degrees of short noses were included in this retrospective study. All patients underwent nose elongation surgery using an ePTFE implant. Nasal lengths before and after surgery were measured using a 3-dimensional simulation technology. Outcomes and complications including possible underlying reasons were analyzed. Patient satisfaction was evaluated using a self-assessment survey. Nasal elongation was successfully achieved using ePTFE. Mean increase in nasal length was 4.36 ± 0.85 mm. The mean follow-up period was 13.3 months, ranging from 6 months to 8 years. Follow-up examinations demonstrated stable results. The overall complication rate was 6.8%. Complications included infection, implant extrusion, migration, deviation, visibility, and/or prominence, tissue reaction, and reddening of the nasal skin. Most patients (93.6%) rated their outcome as improved and much improved. Nasal elongation using ePTFE implantation is a feasible therapeutic approach for patients with short noses. Reliable outcomes and the absence of donor site morbidity contribute to the high patient acceptance. Meticulous surgical technique and careful patient selection are prerequisites for successful results.

Susceptibility of ePTFE vascular grafts and bioengineered human acellular vessels to infection

BackgroundSynthetic expanded polytetrafluorethylene (ePTFE) grafts are routinely used for vascular repair and reconstruction but prone to sustained bacterial infections. Investigational bioengineered human acellular vessels (HAVs) have shown clinical success and may confer lower susceptibility to infection. Here we directly compared the susceptibility of ePTFE grafts and HAV to bacterial contamination in a preclinical model of infection. Materials and methodsSections (1 cm2) of ePTFE (n = 42) or HAV (n = 42) were inserted within bilateral subcutaneous pockets on the dorsum of rats and inoculated with Staphylococcus aureus (107 CFU/0.25 mL) or Escherichia coli (108 CFU/0.25 mL) before wound closure. Two weeks later, the implant sites were scored for abscess formation and explanted materials were halved for quantification of microbial recovery and histological analyses. ResultsThe ePTFE implants had significantly higher abscess formation scores for both S. aureus and E. coli inoculations compared to that of HAV. In addition, significantly more bacteria were recovered from explanted ePTFE compared to HAV. Gram staining of explanted tissue sections revealed interstitial bacterial contamination within ePTFE, whereas no bacteria were identified in HAV tissue sections. Numerous CD45+ leukocytes, predominantly neutrophils, were found surrounding the ePTFE implants but minimal intact neutrophils were observed within the ePTFE matrix. The host cells surrounding and infiltrating the HAV explants were primarily nonleukocytes (CD45−). ConclusionsIn an established animal model of infection, HAV was significantly less susceptible to bacterial colonization and abscess formation than ePTFE. The preclinical findings presented in this manuscript, combined with previously published clinical observations, suggest that bioengineered HAV may exhibit low rates of infection.

In vitro and in vivo evaluation of a small-caliber coaxial electrospun vascular graft loaded with heparin and VEGF

IntroductionTo date, clinically available expanded polytetrafluoro-ethylene (ePTFE) vascular grafts are suboptimal for reconstructing small caliber (D < 6 mm) arteries, owing to thrombosis in early and restenosis in late stage. Our aim in this preliminary study was to fabricate a nano-fibrous vascular graft which was biofunctionalized with VEGF165 and heparin. The short term performance was evaluated both in vitro and in vivo. MethodFour-mm caliber grafts were prepared by the coaxial-elctrospun technique, which consisted of poly(l-lactide-co-caprolactone) [P(LLA-CL)] collagen and elastin. Heparin and endothelial cell growth factor-165 (VEGF165) were encapsulated in the core of the fibrous. Controlled release of the heparin and VEGF165 were evaluated for 28 days. Endothelial cells were cultured on the electrospun grafts or ePTFE grafts as controls. The cellular adhesion, proliferation and morphology were examined. Electrospun or ePTFE grafts were randomly implanted into a rabbit infrarenal aortic replacement model (n = 30) for 28 days without any antiplatelet therapy. At the termination, all grafts were examined by Doppler ultrasound and then evaluated with histology and scanning electron microscopy. ResultsThe cumulative release amount of heparin (6.93 ± 1.03 mg) and VEGF165 (22.17 ± 5.56 μg) during 28 days were measured. Endothelial cells cultured on electrospun grafts showed significantly higher attachment efficiency and proliferation compared to the ePTFE ones (P < 0.001). At 2 h more ECs had attached to the P(LLA-CL)/Collagen/Elatin grafts (83.26 ± 8.02%) compared to P(LLA-CL) (67.07 ± 4.16%) and ePTFE (46.87 ± 8.85%). ECs proliferated faster on VEGF loaded grafts (O.D = 2.9 ± 1.2, n = 12) compared to ePTFE (O.D = 1.7 ± 1.0, n = 12). The patency was significantly higher in electrospun grafts (86.6%) than ePTFE grafts (40.0%) (P = 0.021). Correspondingly, the microscope images of electrospun implants showed little thrombus when compared with the ePTFE implants. ConclusionBiofunctionalized electrospun graft showed surgical properties, hemocompatibility and higher short-term patency compared with the ePTFE grafts. Despite good early performances, profound study should be designed for long-term evaluation.

Anti-inflammatory and Antibacterial Effects of Covalently Attached Biomembrane-Mimic Polymer Grafts on Gore-Tex Implants.

Expanded polytetrafluoroethylene (ePTFE), also known as Gore-Tex, is widely used as an implantable biomaterial in biomedical applications because of its favorable mechanical properties and biochemical inertness. However, infection and inflammation are two major complications with ePTFE implantations, because pathogenic bacteria can inhabit the microsized pores, without clearance by host immune cells, and the limited biocompatibility can induce foreign body reactions. To minimize these complications, we covalently grafted a biomembrane-mimic polymer, poly(2-methacryloyloxylethyl phosphorylcholine) (PMPC), by partial defluorination followed by UV-induced polymerization with cross-linkers on the ePTFE surface. PMPC grafting greatly reduced serum protein adsorption as well as fibroblast adhesion on the ePTFE surface. Moreover, the PMPC-grafted ePTFE surface exhibited a dramatic inhibition of the adhesion and growth of Staphylococcus aureus, a typical pathogenic bacterium in ePTFE implants, in the porous network. On the basis of an analysis of immune cells and inflammation-related factors, i.e., transforming growth factor-β (TGF-β) and myeloperoxidase (MPO), we confirmed that inflammation was efficiently alleviated in tissues around PMPC-grafted ePTFE plates implanted in the backs of rats. Covalent PMPC may be an effective strategy for promoting anti-inflammatory and antibacterial functions in ePTFE implants and to reduce side effects in biomedical applications of ePTFE.

Improving the Biocompatibility of Implants in Irradiated Tissue Using an Adipose-Derived Stromal-Vascular Fraction

Improving the Biocompatibility of Implants in Irradiated Tissue Using an Adipose-Derived Stromal-Vascular Fraction

Safety and Efficacy of Expanded Polytetrafluoroethylene Implants in the Surgical Management of Traumatic Nasal Deformity.

The ideal alloplastic implant for correction of traumatic nasal deformity has not been adequately examined. To evaluate the safety profile and postoperative results of expanded polytetrafluoroethylene (ePTFE) implants used in functional nasal surgery (FNS) in the setting of traumatic nasal deformity. We conducted a 13-year retrospective medical chart review for patients treated at a tertiary academic facial plastic and reconstructive surgery practice between July 1999 and July 2012. A total of 404 FNS procedures were performed by a single surgeon during this period, 255 to repair traumatic deformities, 35 of these involving ePTFE implants. Patient demographics, medical comorbidities, operative and technical considerations, functional and aesthetic results, complications, and postoperative course findings were collected from patient records. In addition, preoperative and postoperative photographic documents were examined. Functional nasal surgery. Postoperative complications or presentations necessitating revision. A total of 404 patients (197 male, 207 female) underwent FNS. Of those, 255 procedures were to treat traumatic deformities. Forty patients altogether required the use of an ePTFE implant, 35 of those 40 deformities being associated with a traumatic injury. One of the 35 patients in the ePTFE-repaired traumatic deformities group experienced postoperative infection. This patient ultimately developed exposure after the infection failed to resolve with oral antibiotics, and the implant was removed. An additional patient in the ePTFE group required revision of the implant owing to contour irregularity and aesthetic concerns. No infections or other complications occurred among the 220 patients with traumatic deformity treated with autologous grafts. Analysis of other variables including sex, tobacco use, diabetes, immunosuppression, implant thickness, suture material, and prior septorhinoplasty were not associated with increased rate of infection (P > .05 for all). In the setting of traumatic nasal deformities requiring FNS, ePTFE implants can be used at the level of the nasal dorsum, where soft tissue coverage is often adequate, with a low risk of complications.

Investigation of Nasal Mobility in Asians and its Change After Alloplastic Augmentation

Augmentation rhinoplasty is one of the most popular cosmetic surgeries in Asia, and both dorsal augmentation and mobile nose modifications are emphasized for the characters of the Asian nose and for Asians who are fond of the Western nasal shape. The goal in rhinoplasty is to create a balanced and natural appearance. Therefore, the cosmetic aspects, postoperative complications, and functional aspects should be regarded as a whole. In fact, the first 2 aspects had been widely reported in a large number of literatures. However, the functional aspects about mobility have been ignored by most surgeons. A sample method was used in this article to investigate the range of mobility of normal nasal tip in Asians and analyze the correlations of the nasal mobility and alloplastic materials. A total of 170 healthy adult subjects aged from 18 to 35 were included and were classified into 3 groups standing for normal nose and rhinoplasty with L-shaped silicon implants with e-PTFE implants. A 3D raster surface scanner was used to capture the images of the subjects accurately and rapidly in this detailed anatomical study. The range of nasal mobility (to right or left) in Asian normal women was 35.53 ± 4.84 degrees, and the length of mobile part was 16.62 ± 1.94 mm, which accounts for 40% ± 5% of nasal length. The L-shaped alloplastic implants would reduce the nasal mobility, and there had been differences among the changes caused by different implants, which might cause unsatisfactory outcomes in patients. Results of the study indicated that augmentation rhinoplasty should be performed as well as augmented mammaplasty which attaches importance not only to the static and dynamic appearance of the nasal tip but also to the feeling when it is touched.

Wound Healing - A Proteomic Analysis of the Effect of Erythropoietin on Granulation Tissue Isolated from ePTFE Implants

Background: Erythropoietin is a multifunctional cytokine, with recent studies indicating a positive effect on wound healing in models of incisional and burn wounds. Objective: The objective of this study was to investigate the changes in protein expression after daily injections of recombinant human erythropoietin in granulation tissue isolated from subcutaneous implants of expanded polytetrafluoroethylene (ePTFE tube). Methods: ePTFE tubes were implanted subcutaneously in twelve C57bl6 mice. Six of the mice were treated with daily subcutaneous injection of recombinant human erythropoietin of 1000 IU/kg. The remaining six mice, the control group, were treated with injections of 0.9% saline. The implants were removed on day 9 after implantation. The granulation tissue was isolated and analyzed for protein expression using a proteomic approach including two-dimensional polyacrylamide gel electrophoresis and mass spectrometry. Some of the results were confirmed with Western Blotting. Results: We identified 33 differentially expressed proteins in the rhEPO-treated group. Three proteins involved in the glycolytic pathway — Glyceraldehyde-3-phosphate dehydrogenase, Alpha-enolase, and Triosephosphate isomerase — were altered in the granulation tissue from the rhEPO-treated group. Conclusion: Daily injection of recombinant human erythropoietin of 1000 IU/kg alters the protein expression of GAPDH, ENOA and TPIS in granulation tissue from wounds on postoperative day 9. The successful combination of proteomic analysis of wound tissue and the ePTFE wound model could advance our knowledge of the complex healing process.

Do collagen meshes offer any benefits over preclude® ePTFE implants in contaminated surgical fields? A comparative in vitro and in vivo study

The surgical repair of an abdominal wall defect may be complicated by infection. We examined the in vitro and in vivo behavior of Staphylococcus aureus (Sa) and Staphylococcus epidermidis (Se) when placed in contact with three collagen bioprostheses. For the in vitro study, 1 cm(2) fragments of the collagen meshes (Collamend®, Surgisis®, and Permacol®) and a control polytetrafluoroethylene mesh, Preclude®(ePTFE) were incubated on blood agar plates inoculated with Sa or Se. In the in vivo study, 2 partial 3 × 3 cm defects were created in the abdominal wall of 72 rabbits and infected with a suspension-containing 10(6) Colony-forming unit (CFU) of Sa or Se. The defects were then repaired using the above materials. At 14 and 30 days postimplant, mesh specimens were obtained for histological, morphometric, and biomechanical analysis. The incubated collagen meshes showed significantly greater bacterial loads than the ePTFE. In vivo, large abscesses comprised of bacteria (Sa/Se), detritus and white cells could be seen 14 days post-implant. At 30 days, the bacterial infiltrate was reduced in the Se group. In conclusion, in presence of bacterial contamination, no benefits were observed of the use of the collagen bioprostheses tested over the use of a non porous ePTFE mesh (Preclude®).

Porcine carotid artery replacement with biodegradable electrospun poly-e-caprolactone vascular prosthesis

There is a continuous search for shelf-ready small-caliber vascular prostheses with satisfactory early and late results. Biodegradable scaffolds, repopulated by recipient's cells regenerating a neovessel, can be a suitable option for adult and pediatric, urgent and elective cardiovascular procedures. This was a short-term experimental assessment of a new biodegradable vascular prosthesis for arterial replacement in the pig. Eleven pigs underwent bilateral carotid artery replacement with biodegradable electrospun poly-ε-caprolactone (PCL) nanofiber prostheses (internal diameter, 4 mm; length, 5 cm); or expanded polytetrafluoroethylene (ePTFE) prostheses as control. Perioperative anticoagulation was achieved with intravenous heparin (double baseline activated clotting time). Postoperatively, until conclusion of the study at 1 month, animals received aspirin and clopidogrel daily. Transit time flow was measured intraoperatively and at sacrifice. Doppler ultrasound (1 and 4 weeks) and a selective carotid angiography (4 weeks) were performed to assess patency. All explanted grafts were analyzed by histology, morphometry, and scanning electron microscopy in order to study graft-host interaction. Surgical handling and hemostasis of the new prostheses were excellent. Patency rate was 78% (7/9) for PCL grafts, compared with 67% (4/6) for ePTFE grafts. Transit time flow and Doppler ultrasound showed no significant changes in flow and velocity or diameter over time in both groups. Both prostheses showed no detectable in vivo compliance as compared with native carotid artery. Percent neoendothelialization was 86% for PCL and 58% for ePTFE grafts (P = .008). Neointima formation was equal in both grafts. More adventitial infiltration of macrophages, myofibroblasts, and capillaries was seen in PCL grafts with a milder foreign-body reaction when compared with ePTFE implants. Both grafts showed similar endoluminal thrombus formation. Biodegradable, electrospun PCL grafts showed good surgical and mechanical properties, no aneurysm formation, and similar short-term patency compared with ePTFE grafts. Rapid endothelialization and cell ingrowth confirms favorable PCL graft-recipient biological interaction. Despite good early results, long-term follow-up is required before clinical application.

Comparative Study of Morphological and Histological Changes between Differently Structured Expanded Polytetrafluoroethylene Implants in an Animal Model

Expanded polytetrafluoroethylene (e-PTFE) is a popular graft material used in augmentation rhinoplasty. New e-PTFE has thicker fibrils and is more compact than first developed e-PTFE. This study aimed to compare morphological and histological changes between differently structured e-PTFE implants in a rat model. Two types of e-PTFE were implanted in the cranial region of 30 adult male rats. En bloc specimens containing the implants and surrounding soft tissues were sampled 1, 3, and 6 months after implantation. We measured the three-dimensional size of the implants over time and evaluated histological changes using light and electron microscopy. Grossly, no implants were extruded, and there was no evidence of wound infection. All first developed e-PTFE samples were fixed to surrounding tissues after 1 month, whereas new e-PTFE samples tended to migrate and were easily separated from surrounding tissues until 3 months after implantation. The first developed e-PTFE height diminution rate was 14.7% of the initial value after 6 months; however, new e-PTFE size was not changed. Diameter and height diminution rates for first developed e-PTFE were significantly greater than those for new e-PTFE after 6 months. Histologically, connective tissue in growth was observed in first developed e-PTFE after 1 month, and the internodal space decreased over time; however, connective tissue did not infiltrate into new e-PTFE until 6 months and the internodal space was not significantly changed. First developed e-PTFE should be carefully trimmed in augmentation because of its potential to decrease in size over time, whereas new e-PTFE is more likely to show migration and instability.

Expanded Polytetrafluoroethylene as Dorsal Augmentation Material in Rhinoplasty on Southeast Asian Noses

Objective To describe the outcomes of dorsal augmentation rhinoplasty with expanded polytetrafluoroethylene (ePTFE) implants in Southeast Asian patients from the Philippines. Methods Retrospective ...

Gore-Tex Nasal Augmentation

Gore-Tex Nasal Augmentation

Enhancement of capillary and cellular ingrowth in ePTFE implants with a proangiogenic recombinant construct derived from fibronectin

Based on our discoveries of a unique, synergistic interplay between vascular endothelial growth factor (VEGF) and specific domains of the matrix protein fibronectin (FN), we used recombinant technology to create a new protein construct derived from the cell-binding and VEGF-binding domains of FN. We wished to test the hypothesis that this prototype recombinant FN (rFN) protein would enhance cellular and capillary ingrowth in vivo into expanded polytetrafluoroethylene (ePTFE) implants. ePTFE disks of high porosity (60 micron internodal distance) were embedded with fibrin gel and heparin, with/without mixtures of VEGF and rFN and were implanted subcutaneously in rats. Control implants embedded with fibrin glue and heparin alone showed an average of 8.5% (±0.51% standard error mean (SEM)) cellular ingrowth. The addition of either VEGF or rFN caused a modest but significant increase in cellular ingrowth (12.7 ± 1% and 11.8 ± 0.98%, respectively, p < 0.004). However, the combination of rFN/VEGF/heparin dramatically increased cellular ingrowth (27.6 ± 1.62%, p < 0.001), compared with all other treatments. Quantification of capillary ingrowth yielded the same pattern. These results suggest that the incorporation of such biological modulators into cardiovascular implants could offer new strategies for the design of a ready-made small diameter prosthetic graft with enhanced capacity for neovascularization and endothelialization.

Incorporation by host tissue of two biomaterials used as repair of defects produced in abdominal wall of rats

Biomaterials may be used as treatment of great abdominal wall defects to avoid tension during repair. In the present research we intended to investigate incorporation type by host tissue of membranes of microbial cellulose (MC), produced by the bacteria Zoogloea sp., and of polytetrafluoroethylene (ePTFE) in abdominal wall defects of rats. Sixty male rats Wistar, anesthetized by ketamine (5mg/100g) and xylazine (2mg/100g), were submitted to a rectangular excision (2 x 3cm) of the abdominal wall, including fascia, muscles and peritoneum and further treated with implants of microbial cellulose (MC Group - 30 animals) or expanded polytetrafluoroethylene ( ePTFE Group- 30 animals). Each group was subdivided in 14th DPO, 28th DPO and 60th DPO Subgroups. Incorporation of biomaterials was observed by wrapping and infiltration by host tissue. It has been found that wrapping associated to infiltration of host connective tissue in implants of ePTFE were present in 100% of the observed samples, and this may be responsible for increase resistance to traction. Inversely, wrapping without host tissue infiltration was seen in 100% of examined specimens of MC implants. Wrapping and host tissue infiltration is seen only in ePTFE implants.

EPTFE implants for hypoplastic lips in cleft lip and palate patients

Objective: This study was conducted to assess the functional and cosmetic outcome of expanded polytetrafluoroethylene (ePTFE) implants for hypoplastic lips in operated cleft lips and palate patients. Methods: ePTFE implants were placed in 15 patients with hypoplastic upper lips following repair of cleft lip and palate. These patients were assessed post-operatively for functional and cosmetic acceptance and complication. Results: Cosmetic and functional results were extremely satisfactory for all the patients. Postoperative infections occurred in two patients warranting removal of implants. Conclusion: ePTFE lip implants are an excellent option for hypoplastic lips but further long-term evaluation is required.