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In recent years, biologic ceramics is a popular material of implants and bioactive surface modification of dental implant
became a research emphasis, which aims to improve bioactivity of implants materials and acquire firmer implants-bone
interface. The zirconia ceramic has excellent mechanical properties and nanometer HA ceramics is a bioceramic well
known for its bioactivity, therefore, nanometer HA ceramics coating on zirconia, allows combining the excellent
mechanical properties of zirconia substrates with its bioactivity. This paper shows a new method for implant shape
design and bioactive modification of dental implants surface. Zirconia's implant substrate was prepared by sintered
method, central and lateral tunnels were drilled in the zirconia hollow porous cylindrical implants by laser processing.
The HA powders and needle-like HA crystals were made by a wet precipitation and calcining method. Its surface was
coated with nanometer HA ceramics which was used brush HA slurry and vacuum sintering. Mechanical testing results
revealed that the attachment strength of nanometer HA ceramics coated zirconia samples is high. SEM and interface
observation after inserted experiment indicated that calcium and phosphor content increased and symmetrically around
coated implant-bone tissue interface. A significantly higher affinity index was demonstrated in vivo by
histomorphometric evaluation in coated versus uncoated implants. SEM analysis demonstrated better bone adhesion to
the material in coated implant at any situation. In addition, the hollow porous cylindrical implant coated with nanometer
HA ceramics increase the interaction of bone and implant, the new bone induced into the surface of hollow porous
cylindrical implant and through the most tunnels filled into central hole. The branch-like structure makes the implant and
bone a body, which increased the contact area and decreased elastic ratio. Therefore, the macroscopical and microcosmic
nested structure of implant coated nanometer HA ceramics had increased biocompatibility and improved the
osteointegration. It endows the implants with new vital activity.
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