Types of Dental Implant Materials — Titanium vs Zirconia

History of Dental Implant Materials

Prior to this and even since then, other materials have been tested and tried. Vitreous carbon was one material which worked very well in fusing to bone, but being brittle and having other issues made it impractical for use as a dental implant. Titanium seemed like an ideal material—its properties made it useful, practical and predictable. The initial implants were pure titanium, but they were a bit too soft so an alloy was developed to overcome the negative properties.

Today, well over 95% of the dental implants placed are titanium alloys. There are literally hundreds of implant companies and systems worldwide and when scientific and surgical protocols are followed, the success of these implants are all well over 98% even after 10 years.

Since titanium dental implants have been in use, there has not been one report of an allergy or reaction to the metal itself. Nevertheless,there are some people who have either an allergy or sensitivity to other metals (e.g. prevalence of nickel allergy is about 5%) and/or simply have concerns about any metals within the body.

Zirconium—The Metal-Free Option?

In order to allay these concerns and have an implant option for these people, several companies have conducted further research and development into “metal-free” implants. This has led to the use of another metal called zirconium, which is just one row below titanium in the chemical periodic table.. Zirconium first became popular in its crystalline cubic zirconia form due to its resemblance to a flawless diamond. For dental use, it is used in the form of zirconium oxide ZrO2. It is not pure ZrO2—there are trace amounts of another metal called hafnium (Hf) and the oxide is combined with yttrium (another metal) to improve its properties. The result is a white opaque-looking product and in this form, labeled as a ceramic, although there are metal atoms within the material.

The material is very strong and hard and has also been used for making crowns and bridges. With the search for alternative implant materials, it was discovered that zirconia also fused to bone (osseointegrated) much like titanium.

Advantages of Zirconia Dental Implants

Advocates of zirconia state several advantages of the material:

1. No dark colour of the metal showing through the gums

2. No corrosion of the zirconia as with titanium

3. No piezo-electric currents between dissimilar metal in the mouth

4. It is thermally non-conductive

According a manufacturer of zirconia implants: “The gradual degradation of materials by electrochemical attack is a concern particularly when a metallic implant is placed in the hostile electrolytic environment provided by the human body.”

On the other hand, while zirconia has its perks, much less is known about the role played by surface modifications on the osseointegration of zirconia dental implants