Zirconia Implant Abutments

Zirconia Implants and Abutments



Dental implants are usually made from titanium owing to its well-documented biocompatibility and suitability for tooling. One drawback from an aesthetic point of view is the gray colour of titanium, which may pose a problem in cases with visible titanium and thin soft tissues. One solution to this problem would be to make implants from tooth-coloured materials, such as ceramics.
Zirconia ceramics have been shown to have several advantages over other ceramics owing to their mechanical properties, that is, high fracture toughness and bending strength. They have extensively been used as ball heads in total hip replacements, with good clinical outcomes. Animal studies have demonstrated bone integration of threaded zirconia implants under both unloaded and loaded conditions. Akagawa and colleagues studied the clinical performance of loaded zirconia implants during 24 months in a monkey model. No mechanical problems, such as fractures of the implant material, were reported. In addition, histology showed high degrees of bone-implant contacts. Their findings are in line with those of Kohal and colleagues, who compared custom-made titanium and zirconia implants supporting single crowns in the maxilla of six monkeys.
One case report from the same group demonstrated the clinical use of a custom-made zirconia dental implant in the anterior maxilla. However, no follow-up data were presented. Thus, the available documentation indicates that zirconia ceramics are suitable materials to be used as dental implants. Turning of zirconia rods results in a relatively smooth surface, and modern implant research shows that a rough surface topography is desirable to enhance the bone integration process.
Sennerby and others in an animal study showed a strong bone tissue response to surface-modified zirconia implants after 6 weeks of healing in rabbit bone. The modified zirconia implants showed a resistance to torque forces similar to that of...