Drug Delivery from Nanoporous Titania Coatings for Dental ApplicationPart of:
Although tooth implants are a common treatment in dentistry nowadays, peri-implantitis remains a major health issue. Bacteria may form biofilms on the implants’ surface, caused by late infections, leading to high implant failure rates (>10%).[1,2] To prevent and cure these infections the bacteria have to be effectively eliminated shortly after implantation and biofilm formation has to be inhibited during the life-time of the implant. Thus, a controlled drug delivery system directly located on the implants’ surface offers a promising opportunity to accomplish the required antibacterial effect. A stimuli-response system is desired in order to ensure the release of an antibacterial drug if an infection occurs. Therefore, a nanoporous titania coating that can be attached to the implant surface seems to be suitable for both, the modification of the surface to introduce the stimuli-response effect as well as hosting of drug molecules. A similar system was already accomplished successfully for silica nanoparticles. The first step to transfer the system to a titania surface was the establishment of nanoporous titania films by utilizing an adjusted cathodic electrodeposition method of Hu et al. In a further step, the surface was modified with phosphonic acids, which form strong chemical bonds to titania. The next step will be the attachment of a responding polymer employing a reaction route described by Menzel and co-workers..
We were able to successfully attach different phosphonic acids to our electrodeposited titania surfaces. The modified and unmodified nanoporous titania films were examined by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), zeta-potential measurements and contact angle measurements (CA). Furthermore, first release experiments of a fluorescent dye from the coatings were performed.
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