In the spirit of getting (half) of my braces off earlier this week- I thought I’d talk about the use of ceramics in dental procedures (because beautiful teeth = cosmetics, right?)

Since the 1960’s, the go-to choice for all dental implants was titanium oxide. However, there were a few drawbacks to titanium. First, there were concerns that people would be allergic to the titanium screws, but what was found is that less than 1% of people have an allergy to pure titanium. Another concern was their dark color, rising concerns about esthetics. For that reason, there came the zirconia implants in 1987.

Zirconium oxide (zirconia) is a ceramic material that is white in color. Color is the key reason zirconia implants are preferred in many situations now. However, we still must consider the material properties and the ways the ceramic interacts with the body to determine if the ceramics square up to the titanium implants, which have a 97% long-term success rate.

In terms of interaction with bone, both zirconia and titanium share a very similar bone-implant contact (Manzano et al. 2014). This contact is the amount of bone in contact with the implant, which determines the stability of the implant. This value is similar in both materials, meaning ceramics are just as effective as titanium.

In terms of placement and the actual implant process, usually, a screw is placed first, and then allowed to heal under the gums before the fake tooth is actually placed. However, zirconia implants are generally not left to heal under the gums. This is because they are designed in a “one-piece” way, such that the abutment cannot be removed, but is fixed to the implanted screw. A consequence of this, is that the dental implant is not given sufficient time to stabilize via osseointegration, a process in which the implant fixates to the bone. This process is critical when the implant is not very stable to begin with, and is a process that generally takes 3-6 months. This could be a limiting factor on the success rates of the implant.

Another concern is that zirconia implants require cementing of the crown onto the implant. Dental cement, however, is not very biocompatible. In the event that dental cement gets lodged into the gums and tissues surrounding the implant, the cement can cause inflammation and bone loss, as well as cause the harboring of bacteria and ultimately cause failure of the implant.

Finally, zirconia, although a strong material, is susceptible to fractures, compared to titanium. This is because ceramics don’t have good flexture, as the material exists only in an elastic state, not plastic. Zirconia can sustain high amounts of compressive force, but not flexural forces. Thus, when the zirconia implants are adjusted, they can easily fracture. In the event that a fracture occurs, particularly in the top of the implant, the dentist would have to create an entire new implant, as they are a one-piece design. Further, any fracture could lead to the propagation of fractures all the way down the screw, making it required for the implant to be removed.

While ceramic implants seem like a wonderful option, they are not necessarily right for everyone. In fact, the nature of the one-piece ceramic implants make it impossible for ceramic implants to be used in full-mouth treatments. Even though both materials are very bioinert, titanium implants can avoid many long-term complications. Ceramics are not the most necessary for esthetic purposes, but can be used in situations where the patient strongly prefers ceramics, without causing any significant drawbacks.

https://www.beverlyhillsladentist.com/blog/are-zirconia-implants-better-than-titanium/