A Study of Doxycycline Release from pH-Responsive Chitosan-PLGA Coated Titanium Nanotubes

Nearly 35 million Americans are missing teeth in one or both jaw, 15 million of those people undergo replacement surgery, and 3 million get dental implants which is increasing by 500,000 yearly. The dental implants however are not always successful. Peri-implantitis is an inflammatory lesion of the tissues surrounding the implants that occurs in 12-43% of the patients. Implant failure can be caused due to bacterial infections, and/or biomechanical overload. Even poor oral hygiene, smoking, and diabetes increase the risk of implant failure, ultimately leading to peri-implantitis. In patients with peri-implantitis, P. gingivalis is found in large numbers as the causative bacteria of the inflammation. Peri-implantitis causes a drop in the pH around the implant leading to acidic conditions which results in the inflammation of the tissue ultimately causing implant failure. Current treatment methods for peri-implantitis include removal of bacterial plaque around the implant, surface decontamination of implants, and delivery of antibiotics by oral route. In more extreme cases, surgical procedures like the removal of the affected implant is performed. However, these solutions have limitations and may be invasive for the patient. Some procedures have to be repeated regularly, some are painful, and the antibiotics may not reach the site of infection leading to recurrence. In this research a novel method is developed to cure peri-implantitis. Titanium nanotubes are synthesized on the surface of pre-fabricated titanium dental implants by electrochemical anodization. The hollow nanotubes serve as a drug reservoir in which the antibiotic drug doxycycline is loaded. The drug loaded nanotubes are coated with layers of pH responsive polymers which degrade at low pH releasing the drug. Ultimately, the drug release study is performed at pH 6.0 and pH 7.4 with the help of UV-Visible spectrophotometer.