RESUMEN
A novel bioresorbable drug-eluting polycaprolactone (PCL) mesh scaffold was developed, utilizing a solvent-cast additive manufacturing technique, to promote therapy of muscle injury. The degradation rate and mechanical properties strength of the PCL mesh were characterized after immersion in a buffer solution for different times. The in vitro release characteristics of vancomycin, ceftazidime, and lidocaine from the prepared mesh were evaluated using a high-performance liquid chromatography (HPLC) assay. In addition, the in vivo efficacy of PCL meshes for the repair of muscle injury was investigated on a rat model with histological examinations. It was found that the additively manufactured PCL meshes degraded by 13% after submission in buffered solution for four months. All PCL meshes with different pore sizes exhibited greater strength than rat muscle and survived through 10,000 cyclic loadings. Furthermore, the meshes could offer a sustained release of antibiotics and analgesics for more than 3 days in vitro. The results of this study suggest that drug-loaded PCL mesh exhibits superior ability to pure PCL mesh in terms of effectively promoting muscle repair in rat models. The histological assay also showed adequate biocompatibility of the resorbable meshes. The additively manufactured biodegradable drug-eluting meshes may be adopted in the future in humans for the therapy of muscle injuries.
Asunto(s)
Implantes Absorbibles , Mallas Quirúrgicas , Ratas , Humanos , Animales , Antibacterianos/farmacología , Antibacterianos/química , MúsculosRESUMEN
Over the past decade, melt electrospinning writing has attracted renewed attention. When combined with three-dimensional (3D) printing capabilities, complex 3D structures can be produced, from ultrafine fibers in the absence of toxic solvents, making it particularly attractive to fabricate customized scaffolds and implants for medical applications. This research aimed to develop novel less stiff vaginal mesh implants for pelvic organ prolapse (POP) repair, matching the physiological biomechanics of vaginal tissues. The main objectives, to attain that goal, were: development of a melt electrospinning writing prototype, with additive manufacturing capability, to produce complex structures from micrometer scale fibers, in a direct 3D printing mode; and design and validate new concepts of biodegradable meshes/scaffolds with new geometries, for POP repair. The melt electrospinning writing prototype was built based on different modules. Biodegradable polycaprolactone was used to produce novel implants: three geometries and two fiber configurations were employed. The commercially available Restorelle® (Coloplast) mesh was used as a benchmark. Printed implants were analyzed via scanning electron microscopy (SEM) and uniaxial tensile testing. The SEM images showed that the geometry is generally well produced; however, some minor deviations are visible due to charge interactions. The tensile test results indicated that, regardless of the geometry, the samples showed an elastic behavior for smaller displacements; aplastic behavior dominates later stages. In the physiological range of deformation, the novel meshes (80 µm fiber diameter) matched the tissue properties (p > 0.05). The Restorelle mesh was significantly stiffer than vaginal tissue (p < 0.05) and novel meshes. The precision of the various geometrical patterns and fiber diameters produced highlights the success of the designed and built prototype equipment. Results showed that the biodegradable meshes produced are biomechanically more compatible with native tissue than commercial implants.