RESUMO
Infection in orthopedic implant surgery is a serious complication and a major cause of implant failure. Upon implant insertion, a contest between microbial colonization and tissue integration of the implant surface ensues. This race for the surface determines the probability of tissue integration or infection, and the surface properties of the substrate have an important role to play in determining the outcome. A number of strategies have been developed for the modification of implant surfaces to promote bone cell (osteoblast) functions and inhibit bacterial adhesion and growth. In this article, a review is given of these surface modification strategies, in particular those which can achieve the dual aim of bacterial inhibition and simultaneous enhancement of osteoblast functions.Surfaces of these types can be expected to have excellent potential for orthopedic applications.
Assuntos
Antibacterianos/farmacologia , Substitutos Ósseos , Materiais Revestidos Biocompatíveis , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Osteoblastos/efeitos dos fármacos , Próteses e Implantes/efeitos adversos , Infecções Relacionadas à Prótese/prevenção & controle , Titânio/química , Animais , Aderência Bacteriana/efeitos dos fármacos , Humanos , Osseointegração/efeitos dos fármacos , Osteoblastos/fisiologia , Desenho de Prótese , Infecções Relacionadas à Prótese/etiologia , Infecções Relacionadas à Prótese/microbiologia , Propriedades de SuperfícieRESUMO
Since bacterial infections associated with implants remain a major cause of their failure, this study investigated the use of polyelectrolyte multilayers (PEMs) comprising hyaluronic acid (HA) and chitosan (CH) to confer antibacterial properties on titanium (Ti). HA and CH were deposited on Ti using the layer-by-layer deposition method. The antibacterial efficacy of the functionalized Ti substrates was assessed using Escherichia coli and Staphylococcus aureus. The number of adherent bacteria on Ti functionalized with HA and CH PEMs was up to an order of magnitude lower than that on the pristine Ti. The effects of chemical crosslinking of the PEMs on the structural stability and antibacterial efficacy were investigated. The chemical crosslinking of the PEMs imparts greater structural stability and preserves the antibacterial properties even after the prolonged immersion in phosphate-buffered saline. The cytotoxicity of the PEMs to osteoblasts was evaluated using the MTT assay. The results showed that the biocompatible and long-lasting antibacterial nature of the functionalized Ti substrates offers great potential for reducing implant-associated infections.