Polylactide Membranes Research Articles

Development of bacterial-resistant electrospun polylactide membrane for air filtration application: Effects of reduction methods and their loadings

The antimicrobial activity of fibrous membranes with electrospun polylactide (PLA)/silver nanoparticles (AgNPs) depends on the accessibility of the AgNPs, among other factors. The challenge is therefore to develop a suitable method for loading the AgNPs onto the fibers. In this study, different techniques for determining the efficacy of the membranes in rendering AgNPs available for antimicrobial activity against Gram-negative Pseudomonas aeruginosa and Gram-positive Staphylococcus aureus bacteria are evaluated. Immersion coating, electrospray-coating, and in-situ loading techniques were used to load AgNPs onto hierarchical electrospun PLA fibers, and their antibacterial effect was evaluated based on a qualitative disc diffusion method. The reduction of AgNO3 (Ag+) to AgNPs was carried out through the use of UV irradiation and neem (Azadirachta indica) leaf extracts. The membranes were coated using an electrospray technique resulted in the best antibacterial activity owing to the uniform dispersion of the AgNPs. The AgNPs were also exposed on the surface of the membranes, as confirmed using scanning electron and transmission electron microscopes. An electrospray is, therefore, a promising technique for the preparation of antimicrobial nanofibrous membranes.

In-vitro antibiofilm activity of chlorhexidine digluconate on polylactide-based and collagen-based membranes

BackgroundIn Guided Tissue Regeneration (GTR), barrier membranes are used to allow selective cell populations to multiply and to promote periodontal regeneration. A frequent complication is membrane exposure to the oral cavity followed by bacterial colonization. The purpose of this in-vitro-study was to elucidate, if rinsing with a chlorhexidine digluconate solution (CHX) prevents bacterial adhesion, and whether it interferes with attachment of periodontal ligament (PDL) fibroblasts and epithelial cells to membrane surfaces.MethodsFirstly, two bioresorbable membranes (polylactide-based and collagen-based) were dipped into 0.06% CHX and 0.12% CHX, before biofilms (2-species representing periodontal health, 6-species representing a periodontitis) were formed for 2 h and 8 h. Subsequently, colony forming units (cfu) were counted. Secondly, the membranes were treated with CHX and inoculated in bacteria suspension two-time per day for 3 d before cfu were determined. In additional series, the influence of CHX and bacterial lysates on attachment of epithelial cells and PDL fibroblasts was determined. Parameter-free tests were applied for statistical analysis.ResultsCfu in “healthy” biofilms did not differ between the two membranes, more cfu were counted in “periodontitis” biofilm on collagen than on polylactide membranes. One-time dipping of membranes into CHX solutions did not markedly influence the cfu counts of both biofilms on polylactide membrane; those on collagen-based membrane were significantly reduced with being 0.12% CHX more active than 0.06% CHX. More-fold CHX dipping of membranes reduced concentration-dependent the cfu counts of both biofilms on both membranes. In general, the number of attached gingival epithelial cells and PDL fibroblasts was higher on collagen than on polylactide membrane. Lysates of the periodontopathogenic bacteria inhibited attachment of PDL fibroblasts to membranes. CHX decreased in a concentration-dependend manner the number of attached gingival epithelial cells and PDL fibroblasts.ConclusionsThe present in-vitro results appear to indicate that membranes in GTR should only be used when bacteria being associated with periodontal disease have been eliminated. An exposure of the membrane should be avoided. Rinsing with CHX may prevent or at least retard bacterial colonization on membrane exposed to the oral activity. However, a certain negative effect on wound healing cannot be excluded.

Sulfonated chitosan and phosphorylated chitosan coated polylactide membrane by polydopamine-assisting for the growth and osteogenic differentiation of MC3T3-E1s

In this study, a poly(d,l-lactide) (PDLLA) membrane was prepared by the solution casting method, then the surface of the membrane was modified by polydopamine (PDOPA) as a substrate, followed by adsorption of different chitosan derivative sulfonated chitosan (SCS) or/and phosphorylated chitosan (PCS) to obtain different functionalized membranes, and two kinds of chitosan derivatives characterized by FTIR, elemental analysis and zeta potential. And different membranes were evaluated through surface potential, hydrophilicity, surface morphology and chemical compositions. In vitro, the cell culture results showed that the membrane functionalized by chitosan derivative could promote the proliferation of MC3T3-E1s and enhance the osteogenic differentiation by up-regulating the expression level of osteogenic genes compared to the PDLLA and P1/PDOPA membranes. Especially, when the outermost layer was SCS, the effect of promoting cell proliferation was better than that of PCS. However, for osteogenic differentiation, PCS had better quantitative experimental results than SCS. Therefore, SCS has superiority in promoting proliferation than PCS, but PCS is opposite in promoting osteogenic differentiation for MC3T3-E1s. The results suggested that PCS and SCS have the potential value to be used as a functional modified materials applied in bone tissue engineering.

Heparin reduced dialysis through a facile anti-coagulant coating on flat and hollow fiber membranes

Heparin free prescription is highly desired for haemodialysis. Versatile strategies have been developed to address the anti-coagulation modification of dialysis membranes. We here develop a facile and effective method to construct an anticoagulant coating on polymeric membranes or a dialyzer through hydrophobic-hydrophobic interaction. An amphiphilic heparin-like copolymer was first synthesized via a free radical polymerization based on alkyl chain lauryl methacrylate (LMA), acrylic acid (AA), and sodium 4-vinylbenze-sulfonate (SSNa) segments. The specific structure of terpolymer was characterized via Fourier transform infrared spectra (FTIR), Proton nuclear magnetic resonance (1H NMR) spectra and size exclusion chromatography (SEC). The amphiphilic copolymer was anchored onto Polylactide (PLA) membrane surface from an aqueous-based solution via hydrophobic-hydrophobic interaction. An Attenuated total reflectance Fourier transform infrared spectra (ATR-FTIR), energy dispersive spectrometer (EDS) and X-ray photoelectron spectroscopy (XPS) confirmed the successful immobilization of heparin-mimicking terpolymers. The modified membranes showed excellent antifouling property and hydrophilicity. Moreover, the membranes exhibited outstanding haemocompatibility with suppressed platelet adhesion, low complement activation (C3a and C5a), expanded coagulation time and limited haemolysis ratio. The prolonged activated partial thromboplastin time and thrombin time (APTT>600 s, TT > 140 s) certified the excellent self-anticoagulant performances. To further examine the applicability and effectiveness, a polysulfone dialyzer was modified by this strategy. The ultrafiltration coefficient and clearance performances were examined. Overall, the hydrophobic-hydrophobic interaction strategy simplified the modification procedure of dialysis membrane, implying its great potential in heparin free dialysis application.

Green and robust superhydrophilic electrospun stereocomplex polylactide membranes: Multifunctional oil/water separation and self-cleaning

Superhydrophilic materials have attracted extensive attention as promising candidates for effective oil/water separation and water purification, however, realizing environmentally friendly and multifunctional materials with superhydrophilicity and underwater superoleophobicity is still a great challenge and urgently desired. In this work, we develop a controllable approach to achieve the superhydrophilicity of biodegradable electrospun stereocomplex polylactide (sc-PLA) membranes via the titanium carboxylate coordination bonding of gallic acid (GA) and tetrabutyl titanate (Ti(OBu)4) in aqueous solution, i.e. GA-modified TiO2 (GA-TiO2) coating. The GA-TiO2 coated sc-PLA (GT-sc) membranes show superhydrophilicity and underwater superoleophobicity in various harsh working conditions including corrosive organic solvents, saturated NaCl solution and acid solution at pH = 1, exhibiting effective and efficient separation property for a wide range of oil/water mixtures and oil-in-water emulsions. The GT-sc membranes can remove water-soluble contaminants such as methylene blue driven by gravity, leading to multifunctional water purification. Moreover, the GT-sc membranes possess splendid antifouling and self-cleaning performance resulting from the photocatalytic property of TiO2 under UV irradiation. Thus, this work provides an easily controlled route for fabricating green and durable membranes for multifunctional oil/water separation.

Comparing Properties of Variable Pore-Sized 3D-Printed PLA Membrane with Conventional PLA Membrane for Guided Bone/Tissue Regeneration.

The aim of this study was to fabricate bioresorbable polylactide (PLA) membranes by 3D printing and compare their properties to those of the membranes fabricated by the conventional method and compare the effect of different pore sizes on the properties of the 3D-printed membranes. PLA membranes with three different pore sizes (large pore-479 μm, small pore-273 μm, and no pore) were 3D printed, and membranes fabricated using the conventional solvent casting method were used as the control group. Scanning electron microscopy (SEM) and micro-computed tomography (µ-CT) were taken to observe the morphology and obtain the porosity of the four groups. A tensile test was performed to compare the tensile strength, elastic modulus, and elongation at break of the membranes. Preosteoblast cells were cultured on the membranes for 1, 3 and 7 days, followed by a WST assay and SEM, to examine the cell proliferation on different groups. As a result, the 3D-printed membranes showed superior mechanical properties to those of the solvent cast membranes, and the 3D-printed membranes exhibited different advantageous mechanical properties depending on the different pore sizes. The various fabrication methods and pore sizes did not have significantly different effects on cell growth. It is proven that 3D printing is a promising method for the fabrication of customized barrier membranes used in GBR/GTR.

Tissue-Engineered Trachea Consisting of Electrospun Patterned sc-PLA/GO- g-IL Fibrous Membranes with Antibacterial Property and 3D-Printed Skeletons with Elasticity.

In this study, a tissue-engineered trachea, consisting of multilevel structural electrospun polylactide (PLA) membranes enveloping 3D-printed thermoplastic polyurethane (TPU) skeletons, was developed to create a mechanically robust, antibacterial and bioresorbable graft for the tracheal reconstruction. The study design incorporated two distinct uses of stereocomplex PLA: patterned electrospun fibers to enhance tissue integration compared to the random layered fibers, meanwhile possessing good antibacterial property; and 3D-printed TPU scaffold with elasticity to provide external support and protection. Herein, ionic liquid (IL)-functioned graphene oxide (GO) was synthesized and presented enhanced mechanical and hydrophilicity properties. More interesting, antibacterial activity of the GO- g-IL modified PLA membranes were proved by Escherichia coli and Staphylococcus aureus, showing superior antibacterial effect compared to single GO or IL. The synergistic antibacterial effect could be related to that GO break cytomembrane of bacteria by its extremely sharp edges, while IL works by electrostatic interaction between its cationic structures and electronegative phosphate groups of bacteria membranes, leading to the loss of cell electrolyte and cell death. Hence, after L929 fibroblast cells were seeded on patterned fibrous membranes with phenotypic shape, further effective cell infiltration, cell proliferation and attachment were observed. In addition, the tissue-engineered trachea scaffolds were implanted into rabbit models. The in vivo result confirmed that the scaffolds with patterned membranes manifested favorable biocompatibility and promoted tissue regeneration.

Schiff base-assisted surface patterning of polylactide–zinc oxide films: generation, characterization and biocompatibility evaluation

A novel route for obtaining ordered microporous polylactide films has been explored using zinc oxide and a Schiff base. The SEM images reveal that the water vapor condensation near the surface of a polylactide solution containing a synthesized Schiff base and zinc oxide results in well-dispersed water droplets, which upon subsequent evaporation can assist breath figure patterning. The generation of ordered micropores at the film surface is attributed to the interaction between the surface +ve charge of well-dispersed zinc oxide particles and the δ-bearing water droplets from moisture. The potential for biocompatible applications has been revealed for the membranes by the cell viability assay against mice fibroblast (L929) cells and the hemocompatibility assay. The findings suggest an efficient route for the development of porous biodegradable polylactide membranes for various applications, typically for wound dressing.

Effects of Polylactide Copolymer Implants and Platelet-Rich Plasma on Bone Regeneration within a Large Calvarial Defect in Sheep.

The aim of this study was to verify whether L-lactide/DL-lactide copolymer 80/20 (PLDLLA) and platelet-rich plasma (PRP) trigger bone formation within critical-sized calvarial defects in adult sheep (n = 6). Two craniectomies, each ca. 3 cm in diameter, were created in each animal. The first craniectomy was protected with an inner polylactide membrane, filled with PRP-polylactide granules, and covered with outer polylactide membrane. The second control craniectomy was left untreated. The animals were euthanized at 6, 7, 17, 19, 33, and 34 weeks after surgery, and the quality and the rate of reossification were assessed histomorphometrically and microtomographically. The study demonstrated that application of implants made of PLDLLA 80/20 combined with an osteopromotive substance (e.g., PRP) may promote bone healing in large calvarial defect in sheep. These promising proof-of-concept studies need to be verified in the future on a larger cohort of animals and over a longer period of time in order to draw definitive conclusions.

Development of bioabsorbable polylactide membrane with controllable hydrophilicity for adjustment of cell behaviours.

Cell functions can be mediated through their interactions with the microenvironments, which highly depend on the surface state of the substrate. However, how to finely adjust the surface of biomaterials is still very challenging. In this study, poly(d,l-lactide) (PDLLA) with high molecular weight was synthesized via ring opening polymerization, which was hot-pressed into PDLLA membrane. In order to modify the hydrophobicity of the membrane (a limiting factor for its biomedical application), an amphiphilic monomethoxyl poly(ethylene glycol)-b-poly(d,l-lactide) (PEG-PDLLA) was selected to improve its surface hydrophilicity through a simple self-assembly approach. It was found that the contact angles of the modified membrane can be well controlled by variation of PEG-PDLLA concentrations. In vitro cell biological study indicates that optimized cell adhesion can be achieved on the modified membrane with a contact angle of around 50° via its self-assembly with an ethanol/water solution of PEG-PDLA (35 mg ml−1). The surface modification of the membrane also changed its biodegradation property in the process of its incubation period up to 240 days. The surface modification method may afford an effective way for adjustment of the surface (interface) of membrane (scaffolds) of different biomaterials, beyond polylactide.

The membrane with polylactide and hyaluronic fibers for skin substitute.

Skin substitutes are heterogeneous group of scaffolds (natural or synthetic) and cells. We hypothesize that nanofibers with layer composition made of polylactide (PLA) and sodium hyaluronate (HA) obtained using electrospinning method are a good matrix for cell adhesion and proliferation. Optimal conditions of electrospinning of PLA and HA nanofibers to create layered compositions (PLA membrane covered with HA nonwovens) were determined by modifying parameters such as the appropriate amount of solvents, polymer concentration, mixing temperature and electrospinning process conditions. By changing the parameters, it was possible to control the diameter and properties of both polymer fibers. The spinning solution were characterized by surface tension and rheology. A scanning electron microscope (SEM) was used to determine the morphology and fiber diameters: PLA and HA. Structure of the PLA/HA nonwoven was analyzed using spectroscopy (FTIR/ATR). Biocompatibility of the nonwoven with fibroblasts (ECM producers) was assessed in the in vitro conditions. The results showed that stable conditions for the formation of submicron PLA fibers were obtained using a 13% wt. solution of the polymer, dissolved in a 3:1 mixture of DCM:DMF at 45 °C. The hyaluronic fibers were prepared from a 12% wt. solution of the polymer dissolved in a 2:1 mixture of ammonia water and ethyl alcohol. All materials were biocompatible but to a different degree. The proposed laminate scaffold was characterized by a hydrophobic-hydrophilic domain surface with a maintained fiber size of both layers. The material positively underwent biocompatibility testing in contact with fibroblasts.

A novel natural hirudin facilitated anti-clotting polylactide membrane via hydrogen bonding interaction

Different from intensively used anticoagulant heparin, hirudin as a representative of natural bio-molecular inhibitors can form specific hirudin-thrombin complex and function as a serine proteinase to efficiently prevent blood coagulation with less bleeding adverse effect, no allergic reaction and immune of non-toxic reaction. We aim to develop a novel anticoagulant polylactide (PLA) membrane via immobilizing natural hirudin through the hydrogen bonding interaction. High amount of PVP (17.4wt%) was first immobilized on the membrane surface through the interfacial crosslinking of P(VP-VTES). The abundant carbonyl groups with high inter-association constant (K=6000) on the membrane surface dominated the hydrogen bonding interaction with the carboxyl groups of hirudin [44]. The anti-clotting activity of PLA membrane increased with the active hirudin concentration. XPS, ATR-FTIR was conducted to confirm the chemistry evolution of PLA membranes immobilized by PVP and hirudin respectively. The intermediate PVP spacer promoted the hydrophilicity and effectively inhibited the platelet adhesion. While the enhanced hemocompatibility was distinctly revealed by the blood concretion four items (APTT, PT, TT and FIB) mainly thanks to the surface immobilization of hirudin. The anti-clotting stability of PLA membrane was evaluated with varied incubation time. The complement activation was also measured in terms of C3a and C5a. The anti-clotting PLA membrane showed excellent dialysis performances in terms of cleaning urea, creatinine, lysozyme while preserving BSA respectively.

A new strategy to simultaneously improve the permeability, heat-deformation resistance and antifouling properties of polylactide membrane via bio-based β-cyclodextrin and surface crosslinking

The permeability and thermal stability are crucial to the application of environmentally benign, sustainable and bio-based polylactide (PLA) membrane. In the present work, we introduce a bio-based pore forming agent β-cyclodextrin to enhance the permeability of PLA membrane. Furthermore, we improve the protein resistance and heat-deformation resistance via a surface crosslinking strategy. P(VP-VTES) copolymer was first synthesized and seeded on the surface of PLA membranes steadily through the swelling, hydrolysis and condensation. The physicochemical property of PLA membrane was characterized by XPS, FTIR and SEM. The hydrophilicity, pure water flux and BSA fouling resistance were evaluated respectively. The crystallization evolution of PLA membrane was investigated by DSC and XRD. It was found that the surface crosslinked P(VP-VTES) significantly improved the hydrophilicity, dry membrane flux recovery (~98%) and BSA resistance. Meanwhile, the surface crosslinking induced the crystallization of PLA membrane up to ~38% degree of crystallinity and withstood ~100°C hydrothermal treatment without dimension deformation or filtration performance deterioration. This study suggests a simple but effective strategy to simultaneously enhance the fouling resistance and thermal stability, as well as the permeability of PLA membranes through the surface crosslinking and the pore forming agent β-cyclodextrin.

The potential applications of fibrin-coated electrospun polylactide nanofibers in skin tissue engineering.

Fibrin plays an important role during wound healing and skin regeneration. It is often applied in clinical practice for treatment of skin injuries or as a component of skin substitutes. We prepared electrospun nanofibrous membranes made from poly(l-lactide) modified with a thin fibrin nanocoating. Fibrin surrounded the individual fibers in the membrane and also formed a thin fibrous mesh on several places on the membrane surface. The cell-free fibrin nanocoating remained stable in the cell culture medium for 14 days and did not change its morphology. On membranes populated with human dermal fibroblasts, the rate of fibrin degradation correlated with the degree of cell proliferation. The cell spreading, mitochondrial activity, and cell population density were significantly higher on membranes coated with fibrin than on nonmodified membranes, and this cell performance was further improved by the addition of ascorbic acid in the cell culture medium. Similarly, fibrin stimulated the expression and synthesis of collagen I in human dermal fibroblasts, and this effect was further enhanced by ascorbic acid. The expression of beta1-integrins was also improved by fibrin, and on pure polylactide membranes, it was slightly enhanced by ascorbic acid. In addition, ascorbic acid promoted deposition of collagen I in the form of a fibrous extracellular matrix. Thus, the combination of nanofibrous membranes with a fibrin nanocoating and ascorbic acid seems to be particularly advantageous for skin tissue engineering.

Investigation of the heat resistance, wettability and hemocompatibility of a polylactide membrane via surface crosslinking induced crystallization

Polylactide (PLA) has attracted much attention as a sustainable and environmentally friendly material.

Enhancement of growth and osteogenic differentiation of MC3T3-E1 cells via facile surface functionalization of polylactide membrane with chitooligosaccharide based on polydopamine adhesive coating

To develop a chitooligosaccharide(COS)-functionalized poly(d,l-lactide) (PDLLA) membrane to enhance growth and osteogenic differentiation of MC3T3-E1 cells, firstly a thin polydopamine (PDOPA) layer was adhered to the PDLLA membrane via the self-polymerization and strong adhesion behavior of dopamine. Subsequently, COS was immobilized covalently on the resultant PDLLA/PDOPA composite membrane by coupling with PDOPA active coating. The successful immobilization of the PDOPA and COS was confirmed by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). Scanning electronic microscopy (SEM) and atomic force microscopy (AFM) results indicated that the surface topography and roughness of the membranes were changed, and the root mean square increased from 0.613nm to 6.96 and 7.12nm, respectively after coating PDOPA and COS. Water contact angle and surface energy measurements revealed that the membrane hydrophilicity was remarkably improved by surface modification. In vitro cells culture results revealed that the PDOPA- and COS-functionalized surfaces showed a significant increase in MC3T3-E1 cells adhesion, proliferation, osteogenic differentiation and alkaline phosphate activity compared to the pristine PDLLA substrate. Furthermore the COS-functionalized PDLLA membrane was more effectively at enhancing osteoblast activity than the PDOPA-functionalized PDLLA membrane.

Water-permeable polylactide blend membranes for hydrophilicity-based separation

Polymer membranes produced by electrospinning have great potentials in the separation of oil/water emulsion under gravity. Removal of oils from the emulsion has been realized by superhydrophobic membranes due to selective penetration of oils. In this study, we demonstrate that blend electrospinning of polylactide (PLA) with a biodegradable and biocompatible polyester (P34HB) produces membranes with complete water permeability. In contrast, PLA membranes are highly hydrophobic and cannot be penetrated by water. The water permeability is correlated with more hydrophilicity of P34HB than PLA and especially with structural porosity of the membranes. The water-permeable membranes exhibit superior removal of water from the emulsion under gravity, exactly opposite to the situation encountered by superhydrophobic membranes.

Silica Nanoparticle-Mediated Solution-Phase Separation to Highly Porous Polylactide Membranes

Immersion precipitation of polylactide (PLA)/chloroform solutions in methanol yields membranes with lack of pore interconnectivity. In contrast, incorporation of silica nanoparticles (NPs) in the solutions promotes pore interconnectivity throughout the membranes. The selective association of silica NPs with chloroform upon phase separation significantly prevents the contraction caused by the formation of the PLA matrix, thus responsible for pore interconnectivity. Besides, pore size can be tailored by the PLA concentration in the solutions and the polarity of silica NPs. This study demonstrates that silica NPs can mediate solution-phase separation during immersion precipitation, which provides a facile route to achieve highly porous membranes.

Fusion and Self-Assembly of Biodegradable Polymer Particles into Scaffoldlike and Membranelike Structures at Room Temperature for Regenerative Medicine

We report here a novel surfactant mediated fusion of polylactide particles into scaffoldlike structures at room temperature. In the presence of ethanol, evenly spread surfactant coated polylactide particles fused immediately into membranelike structures. Polymer scaffolds of the desired shape and size could be fabricated from polylactide particles using this fusion process. Desorption of surfactant molecules from the surface of the particles during ethanol treatment and the degree of solubility of the polymer in alcohol were found to be the main reasons for the fusion of particles into a scaffold at room temperature. TGA and DSC studies of the polylactide particles showed that the particles were stable at room temperature, and FTIR studies showed that there was no change in characteristics of the polymer after the fusion of particles into a scaffold-type structure. These scaffolds supported three-dimensional growth of animal cells in vitro and release model protein in a sustained manner for a long period of time. In an experimental animal wound model, the polylactide membranes showed faster wound closure, indicating its use as a passive dressing material. This polymer particle fusion process thus provides a novel method of scaffold fabrication for various biomedical applications.

Platelet‐Rich Plasma–Assisted Guided Bone Regeneration for Ridge Augmentation: A Randomized, Controlled Clinical Trial

Platelet-rich plasma (PRP) contains a number of biologically active growth factors, and previous studies have reported conflicting ridge augmentation results. The primary aim of this randomized, controlled, masked, clinical trial was to determine if PRP combined with a rapidly resorbing cancellous allograft would enhance the regenerative result compared with an allograft without PRP. Thirty-two patients with an edentulous ridge defect were sequentially entered into the study; four were excluded from data analysis. Fourteen patients received a cancellous allograft (CAN group) and the other 14 received a cancellous allograft mixed with PRP (PRP group). All 28 grafted sites were covered with a resorbable polylactide membrane. After elevation of a full-thickness flap, horizontal ridge dimensions were measured with a digital caliper at the crest and 5 mm apical to the crest. Vertical ridge dimensions were measured from a tooth-supported stent. All sites were reentered at 4 months, and a trephine core was obtained for histologic analysis before implant placement. The crestal ridge width for the CAN group had a mean gain of 2.0 ± 1.2 mm, whereas the PRP group gained 2.9 ± 1.0, and the difference was statistically significant between groups (P <0.05). The percent vital bone was 36% ± 14% for the CAN group compared with 51% ± 15% for the PRP group and was statistically significant between groups (P <0.05). Loss of augmented ridge width was 34% ± 17% for the CAN group and 28% ± 17% for the PRP group (P >0.05). These clinical and histologic findings suggest that PRP enhanced bone regeneration and resulted in increased horizontal bone gain and percentage vital bone.