This project proposes to enhance technology aimed at improving osseointegration following dental implant. Specifically, we focus on the delivery of plasmid DNA (pDNA) using nanostructured hydroxyapatite particles coated on titanium surfaces. Our hypothesis is that localized expression of osteoinductive proteins will improve healing time and facilitate osseointegration, as well as enhance the efficacy of placing implants in porous type 4 bone. To evaluate the feasibility of intercellular gene delivery off titanium surfaces, we employed a reporter system of green fluorescent protein (GFP) pDNA-NanoCaP particles coated on a titanium surface. MG63 osteoblast cells were seeded on this surface, and later assayed for GFP expression. Twenty-four substrates were assessed: experimental group 2 (Exp2, 400 µl NanoCaP/ 8 µl pDNA) substrates group, demonstrated significantly higher GFP expression values compared to the control (Ctl, 200 µl of ddH2O and 4 µl of pDNA) and Exp (200 µl of NanoCaP and 4 µl of pDNA) groups. Our data show that the coated NanoCaP/pDNA complex can transfect plated cells and that the applied amount of NanoCaPs is critical. In conclusion, we have successfully shown the feasibility of a non-viral approach to deliver plasmid DNA from titanium surfaces and suggest that further optimization is needed
