In vivo bioactivity of DNA-based coatings : an experimental study in rats

DNA-based coatings possess beneficial properties useful for medical and dental implants. The present study evaluated the potential in vivo bioactivity of DNA-based coatings, either or not pretreated in simulated body fluid (SBF). DNA-based coatings were generated on titanium cylinders using layer-by-layer deposition, with bis-ureido-surfactant as the cationic component and DNA as the anionic component. Noncoated titanium implants and CaP-coated implants served as controls. A total of 80 implants, divided in four experimental groups (n = 10) were implanted unilaterally into the lateral femoral condyles of 80 rats. After implantation periods of 1 and 4 weeks, the bone-to-implant contact and bone volume around the implants were determined histomorphometrically. The results of this study showed that DNA-based coatings and CaP coatings increased bone-to-implant contact after 1 week compared to noncoated controls. After 4 weeks of implantation, bone-to-implant contact increased significantly for SBF pretreated DNA coatings and CaP coatings, whereas DNA-coated implants showed no additional effect. The bone-to-implant contact of noncoated controls increased to the level of the DNA-coated implants. Consequently, this study demonstrates that DNA-based coatings are histocompatible and favor early bone responses. SBF-pretreated DNA-based coatings were found to increase both early and late peri-implant bone responses.