Evaluation Of The Biocompatibility Of A Novel HA-CaTiO₃Coating In Vivo

Objective:This study was designed to evaluate the biocompatibility of a novel HA-CaTiO3coating material via an animal experiment, comparing osteointegrative activity of titanium substrate, traditional HA coating CaTiO3coating and our HA-CaTiO3coating. This study has investigated the potential of the HA-CaTiO3coating to be a novel substitution of implant coating material.Method:Four types of screws (type1:coated with HA; type2: coated with CaTiO3; type3:coated with HA-CaTiO3; type4:untreated titanium screws) were implanted respectively into the left and right femoral condyles of48New Zealand rabbits. Histological and mechanical investigations were employed in the end of2,4,8and12weeks, to evaluate the material osteointegration.Results:(1) All of the experimental rabbits were healthy along the experiment process.(2)Histological investigation revealed by microscopy: bone tissue surrounding the screws coated with HA、HA-CaTiO3and CaTiO3were fully regenerated and well integrated with absence of the interfacial fibrous layer.(3) Mechanical investigation:the bonding strength of HA-CaTiO3coating with bone tissue was significantly higher than CaTiO3coating and titanium materials without coating, but lower than those coated with HA.Conclusion:HA-CaTiO3coating possesses the similar admirable biocompatibility and osteointegration activity to HA coating. Chemical bonds contribute to the tight integration of the CaTiO3in HA-CaTiO3coating with titanium substrate and possible with bond tissue, which make it to be a promising coating material to implants in orthopedics.