Hydroxyapatite‐based composite for dental implants: An in vivo removal torque experiment

Abstract

Screw‐shaped dental implants were fabricated from commercially pure Ti (c.p. Ti) and HA‐based composites. The HA‐based composites were fabricated by mixing HA with Al₂O₃‐coated ZrO₂ powders. The mechanical properties of these composites were enhanced by a factor of 3. These were implanted into the rabbit tibiae and the removal torque to loosen the implants in vivo was measured in order to investigate the osteointegration. After a healing period of 6 weeks, the implants were retrieved with a torque gauge instrument. The HA‐based composite implants showed an almost 2‐times‐higher removal torque when compared to the Ti implants (ANOVA, p < 0.05), indicating excellent biocompatibility to bone. Thus, HA‐based composites had not only better mechanical properties but also similar bioactivity as HA itself. It is believed that a HA‐based composite is suitable for artificial dental implants. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res (Appl Biomater) 63: 714–721, 2002