Patients are gaining interest in the safety and types of materials which are being used. This includes the field of dentistry as well. In regards to dental implants, non-toxic and not reactive materials should be used whenever possible. In addition, materials used implants must be strong, durable, have reputable manufacturing sources, and meet other standards.
A dental implant is a popular medical device used to replace one or more missing teeth. Since the early 1960s, titanium implants have been a standard solution. Because of their success in a clinical setting and continuous innovation, titanium implants are one of the most successful medical devices ever used in medicine. The titanium implants have an incredible success rate of about 97%.
Recent trends are moving away from the use of any metal in the body. A popular non-metal alternative to titanium implants is zirconia. Patients are often curious how zirconia implants compare to the titanium version. Unfortunately, there is no simple answer to this question. Patients must have a good understanding of the benefits, limitations, risks, and data in order to proper compare zirconia and titanium dental implants.
Since their introduction in 1987, zirconia implants have continued to gain attention. This is largely based on a growing awareness and interest in holistic and biomimetic dentistry. While zirconia implants are relatively new, dental professionals in the industry are actively conducting clinical research and making improvements from a manufacturing and design perspective. After receiving approval from the FDA in 2011, zirconia implants gained significant momentum and popularity throughout the dental industry. These types of implants have been used for more than a decade in Europe where they have proven to be a stable and biocompatible solution. Not everyone is a good candidate for zirconia implants. However, they may be an excellent solution for some patients.
Zirconia implants are presented to patients as a non-metal alternative to titanium. Zirconia is a ceramic material which is white, but it contains metal and non-metal components.
Zirconia, or Zirconium dioxide, is a ceramic material which contains both Oxygen and Zirconium. More specifically, it contains 1 atom of Zirconium and 2 atoms of Oxygen. Zirconium has an atomic number of 40, meaning it is a transitional metal. As a result of this, zirconia implants contain metallic atoms from the Zirconium, however, this is not technically considered to be metal because of the metal oxide structure (ZrO2). The inclusion of oxide modifies the name, structure, and behavior.
Zirconia Advantages
Zirconia is actually the only solution for patients who want to pursue dental implants, but want to avoid the use of metal. Because the material is completely inert, it is an excellent solution for patients who have a known metal allergy or sensitivity. Zirconia implants can also be more attractive as they do not contain the visible dark lines near the gumline.
When they were originally introduced, zirconia implants were only available as a single unit. More recently, two-piece units were introduced. This introduction allowed for dentists to start using customized abutments which aids in a successful outcome. The gum tissue may also benefit from zirconia implants as the material was found to have lower levels of plaque and calculus compared to patients with titanium implants. When one-piece zirconia implants were used, the levels of plaque and calculus were especially low. Zirconia also has good flexural strength. When compared to other types of ceramics, it is far better at resisting fractures. Other benefits include that the material is naturally white, has low modulus of elasticity, and low thermal conductivity. All of which makes zirconia a great implant solution. In early studies, zirconia had similar success to titanium in its ability to osseointegrated or fuse to the bone. Zirconia allows for a high level of contact between the jaw bone and the implant which allows the bone to successfully fuse with the implant. This allows the implant to form an extremely strong and secure base for the crown. Zirconia has also shown a great ability to resist corrosion.
Disadvantages of Zirconia Implants
One of the greatest disadvantage of zirconia implants is that it has a low-temperature degradation over time. This has the potential to reduce the material’s strength, density, and toughness. Unfortunately, there are not many studies regarding the success of zirconium long term.
Most of the failures found with two-piece zirconia implants were associated with aseptic loosening. Because of the limited research performed on two-piece zirconia implants, some dental professionals prefer to use one-piece implants.
When using single piece zirconia implants, some limitations should be considered. As an example, these implants have fewer abutment angulation options which can compromise the surgical placement of the implant and ultimately the overall success of the procedure. When placing a zirconia implant in a less desirable location, there can be a negative impact on the material’s physical properties. In addition, single piece zirconia implants require a healing period which is load-free which can be difficult to achieve.
Because zirconia implants are relatively new, there are not many clinical studies available regarding the long-term success, life expectancy, and viability of the solution. In comparison, titanium implants have been studied for decades which has produced reliable data validating the durability, longevity, and success of titanium implants. Studies which focus on zirconia implants are unfortunately limited and only include a few years of data.
Although the zirconia studies are limited, they have produced positive results and reported similar success rates to titanium implants. A common complication associated with titanium implants is the use of excess cement which may result in inflammatory reactions. Zirconia implants have not reported this complication, however, this may simply be a result of limited data.
It is difficult to answer which type of implants are superior when comparing zirconia and titanium. This article focused on reviewing the advantages, disadvantages and studies regarding both types of implants. The optimal implant solution will vary based on the patient’s unique priorities and goals in a tooth-replacement solution. While titanium implants have been in use for decades and have more data validating their safety and reliability, zirconia is proving to be a promising alternative solution.