Over the past few
years, surface modification of implant surfaces
has gained substantial attention as a promising solution to avoid
the failure of biomaterials after implantation. Although researchers
suggest several strategies for surface functionalization of titanium-based
implants, only a few studies have compared the osteoimmunomodulatory
effects of ionic nanostructures and biofunctionalization in the same
biological model. Enamel matrix derivate (EMD) and strontium are both
known for their positive influences on bone cell responses. In this
study, we functionalized the titanium–zirconium implant surface
with EMD and strontium using an electrochemical cathodic polarization
method. Afterward, we evaluated the osteoimmunomodulatory effects
of EMD or strontium coated titanium–zirconium implants in the
tibia of eight Gray Bastard Chinchilla rabbits. We performed 2 and
3D micro-CT, wound fluid, histologic, and histomorphometric analyses
on bone tissues after 4- and 8-weeks of implantation. Although the
results could indicate some differences between groups regarding the
bone quality, there was no difference in bone amount or volume. EMD
stimulated higher ALP activity and lower cytotoxicity in wound fluid,
as well as a lower expression of inflammatory markers after 8 weeks
indicating its osteoimmunomodulatory effects after implantation. Overall,
the results suggested that ionic nanostructure modification and biofunctionalization
might be useful in regulating the immune responses to implants.