A Randomized Controlled Clinical Trial of Dental Implants in Titanium-zirconium Alloy

Background

Implants have been used for the purpose of replacing lost teeth since the 1960s. Since then, the treatment of edentulism with dental implants has been implemented in a large scale. The main reason for this is that research has shown that treatment with implants are very predictable in terms of implant survival. The accumulated knowledge, as seen from 15 and 20 year follow-ups, has been based on prerequisites that are not always followed today. One of them is that the implants used in the aforementioned studies are manufactured in titanium that has good rigidity and is used as the main implant material today. In addition, the studies have examined implants with a turned surface. This standard revised in the mid 1990s when a series of studies showed increased and accelerated osseous ingrowth of implants with a moderate raw surface that had been achieved by blasting. The related biological events describing this process have been described in detail in the literature.

Today, other materials are being explored as an alternative to the well documented implant material titanium with a focus on finding a material with higher stiffness combined with equivalent biological characteristics. A stiffer material theoretically gives possibilities for implants installations without bone augmentation in cases with reduced bone volumes.

An alternative implant material which has reached the clinic is titanium-zirconium alloy. It has been shown to have an increased rigidity in comparison with titanium and comparable biological characteristics but the documentation consists mainly of animal studies and short term clinical follow-up in the form of case-series. Since it has been demonstrated that the choice of implant material may influence osseointegration, it is necessary to evaluate the implants made of titanium-zirconium in a clinical controlled study with long-term follow-up in which the emphasis is put on the clinical outcome.

Aims