Nano spray dried antibacterial coatings for dental implants

Nanostructured coatings of dental implants have shown great potential in overcoming many challenges responsible for implant failure. In this study, nano spray drying technology was utilized to produce novel biocompatible nanocoatings with antibacterial activity. The experiments were applied on titanium discs, which were used as a model material for dental implants. The produced nanocoatings consisted of poly(lactic-co-glycolic acid) as a biodegradable polymer and norfloxacin as a model antibiotic. Scanning electron microscopy results revealed an average particle size ranging between 400 and 600 nm. In vitro release studies showed a biphasic drug release profile with a burst release within the first 48 h, followed by a sustained release phase until the end of the experiment. The antibacterial activity of the nanocoatings was evaluated against Escherichia coli where the norfloxacin loaded nanocoatings achieved up to 99.83% reduction in the number of viable bacterial colonies. Finally, in vitro biocompatibility of the nanocoatings was investigated using mouse fibroblasts (L929) as a standard sensitive cell line for cytotoxicity assessment. Cell proliferation on the surface of the titanium discs was studied using fluorescence microscopy followed by cell counting assay. Both methods confirmed the biocompatibility of the examined nanocoatings. In conclusion, nano spray drying is a promising technique for preparing tailor-made nanocoatings, thereby representing an innovative approach for the surface modification of dental implants.