Modeling Bonding Energy in Novel Bio-active Nano Coatings on Dental Implants

摘要

The focus of this research is to propose a method of calculating adhesive strength of nano-crystalline hydroxyapatite (HAp) coatings of dental implants by methods of Density Functional Theory (DFT) and Molecular Dynamics (MD) simulation. Hydroxyapatite is a material similar to bone - that is why it is used in dentistry to cover the implant to improve the process of osseointegration of the implant with the bone. In addition, the nano structure of these new generation coatings also has shown the potential for an improved rate of osseointegration. While fast osseointegration is very attractive, it is also important to have a strong adhesive bond between the coating and the implant, to avoid unpleasant situations with pilling of the coating. A measure of the coating-to-substrate bond strength is the energy of this bond. Using ab-initio calculations, we calculated the binding energies of different combinations of the constituents of the hydroxyapatite coating with titanium, which is the typical material for this implant, and ranked them in order of intermolecular interactions. We used Gaussian06 and a basis set of 6-31G to structurally analyze the bond lengths, bond angles, dihedral angles, and point charges to understand the interactions of these substances and how they contribute to the strength.