HA Coatings on Dental Implants

Abstract

Hydroxyapatite (HA) is one of the most biocompatible materials known and is a bioactive ceramic that has been used as a coating for metal implants, because it enhances bone healing adjacent to implants, and establishes a high interfacial bone—implant strength (1,2). The rationale for the use of HA coatings on metallic implants include stimulation of bone healing, thereby expediting bone—implant stability (Fig. 1), improving the rate of osseointegration, and enhancing the bone—implant interfacial strength (3–10). Thus, the use of HA coatings would speed rehabilitation of patients by decreasing the time from implant insertion to final reconstruction. However, for the past 10 yr, the use of HA-coated dental implants has initiated substantial controversy in dental implantology. The strongest argument against the routine use of HA-coated implants is the general lack of long-term documentation on HA-coated implant survival, as well as the lack of well-characterized coating prior to use. In addition, large degrees of variability between studies, involving the definition and length of implant survival/success, implant case and the site selection, surgeon experience, surgical protocols, postoperative regimens, and prosthetic restoration, makes direct interstudy comparisons problematic (11,12).