A closer look at Hydroxyapatite-Coated Dental Implants

A closer look at Hydroxyapatite-Coated Dental Implants
March 7, 2003
John W. Nelson DDS 2004
Comptons Implants
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Rejection is the body's normal response to a foreign object. An ideal material for dental implants is one that will integrate with ordered, living bone and is biocompatible with the surrounding tissues. The search for improved biocompatibility has resulted in implants fabricated from a variety of materials, using different designs, surface textures, and coatings. At present most dental implants are based on two materials. Those materials are medical-grade titanium (and titanium oxide) and hydroxyapatite-coated implants.
The advantages of coating dental implants with hydroxyapatite has been shown to improve the rate of osseointegration of the implant with ordered, living bone. However, this finding is not the central discussion of this paper. I will be evaluating the advantage hydroxyapatite-coated implants offer to the dental team. Various aspects will be discussed along with any shortcomings of the coated implants.
A rough implant surface has been shown in many studies to improve osseointegration particularly when compared to smooth surfaces. Rough surfaces can be created by a variety of means, which may include ǃ?additionǃ? techniques such as hydroxyapatite coating, or by ǃ?subtractionǃ? techniques such as grit-blasting. Most commonly grit-blasting has involved Al2O3 particles, however, due to the aluminum content there is a danger of contamination. An alternative to an Al2O3 abrasive is to use TiO2, the rationale for which is that it is of the same chemical composition as the surface of commercially pure titanium.
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