Application of TiO2 Nanotubes as a Drug Delivery System for Biomedical Implants: A Critical Overview

TiO2 nanotubes (TNTs) surfaces have been applied as a coating to metallic biomedical implants, presenting promising results in preliminary analyses in terms of integration to living tissues when considering cell adhesion and proliferation, physicochemical properties and biocompatibility. They also present the potential to incorporate drugs and regulate their release to the surrounding tissues. Considering this particular potential, a critical review of the latest studies that considered the possible incorporation of specific drugs like antibiotics, anti-inflamma-tories and/or proteins and cytokines capable of positively influence the healing process at the implant-tissue interface has been considered relevant. Also, a summary about TNTs physicochemical characteristics and biocompatibility studies is presented. Advanced methods for regulating this drug-release mechanism and its specific chemical immobilization in an in vivo environment are discussed, along with TNTs future clinical perspectives.