Dental implants are considered the gold standard for people who wish to replace missing teeth. Dental implants are made of a few different parts, including a tiny post that is surgically placed in the jaw and a dental restoration, like a crown, that is affixed to the top of the post once it has healed. Usually, the implant post that is embedded in the jaw is made of medical-grade titanium, a material that is highly biocompatible, strong, durable, and nonreactive. Some patients, however, have greater concerns about what kinds of materials used in their medical procedure, and some patients wish to specifically avoid metal materials, either due to allergy or simply preference. For these patients, zirconia dental implants could be a suitable and appealing option. While there are some limits to the clinical conditions that will allow zirconia implants, in many cases, zirconia implants can be an optimal solution for patients who wish to avoid metal implants and want to replace missing natural teeth.
Titanium has been successfully used for medical and dental implants since the late 1950s and are considered the industry standard. Titanium dental implants have long-term success rates as high as 97%. Because the titanium used in medical applications is medically purse, and due to titanium’s low reactivity, allergies to titanium implants are rare. If you have a known allergy or sensitivity to certain metals, ask your dentist for a specialized blood-allergy test, called a MELISA test, to determine if you’re also allergic to titanium. If you are, or if you simply don’t want metal implanted in your body, you may prefer zirconia dental implants. Zirconia dental implants were released in 1987 and approved by the FDA in 2011 after demonstrated success in their application in Europe. They continue to increase in popularity since their introduction in the US as an alternative to titanium and are particularly popular among patients who are interested in biomimetic and holistic dentistry options. Because zirconia implants are relatively new on the implant scene, there are limited options for implant parts and designs that use zirconia. This can make it impossible to use zirconia implants in clinically challenging cases, especially when replacing multiple teeth. As research continues, however, the design and production of zirconia implants continues to improve, and the future of expanded zirconia restoration options is promising.
Zirconia is the only option for patients who want dental implants that are metal-free. While there actually is a small amount of metal in zirconia, because the material is entirely inert, it does not react in people with known allergies or sensitivities to metal. Zirconia is a ceramic white material, so zirconia implants that could show through the thin edges of the gum tissue will appear just like natural teeth; with titanium implants, sometimes the metal can show through and create visibly dark areas. While the majority of zirconia implants have been made as one-piece implants, limiting their applications, two-piece zirconia implants were introduced a couple of years ago and have broadened the restoration options for patients whose clinical needs require more versatile restoration components. While one-piece zirconia implants are impressively good at resisting the buildup of bacterial plaque and tartar, all zirconia implants show excellent resistance to bacteria, and zirconia is also strong, resilient, inelastic, and non-conductive.
One of the many benefits of dental implants is the fact that they imitate the roots of the natural teeth, anchoring in the bone to support an artificial tooth while stimulating the bone that supports them. As dental implants heal following placement of the implant posts in the jawbone, the bone that surrounds them fuses to the implants and creates a permanent bond. This process is called osseointegration and is integral to the stability and success of the implant. Zirconia has demonstrated, in clinical studies, that it experiences osseointegration as well as or better than titanium. Because of their relatively short existence, however, long-term research has not been conducted on zirconia implants, and this means that there is insufficient evidence to gauge the longevity of the zirconia implants themselves.
Zirconia demonstrates degradation at low temperatures as it ages, which may result in a reduction in strength, density, and durability as zirconia implants age; again, their lifespan has not been sufficiently tested in the years since their FDA approval. While strong, especially under compression, zirconia is not as strong as titanium, having lower resistance to fracture, which could increase the likelihood of fracture-related complications over time, especially in zirconia implants that are smaller in diameter. They are also more susceptible to cracking than titanium implants. Zirconia implants aren’t recommended for complicated restorations or implant-supported overdentures, and they’re not practical for patients who need to have multiple teeth replaced with implants. Multiple-tooth implant restorations require careful planning and design that uses components in a variety of shapes, sizes, and styles, and these components aren’t available in zirconia – and, due to its mechanical properties, may be challenging, if not impossible, to effectively design in zirconia. To effectively support complicated dental restorations, dental implants may need to be placed at angles in the bone, with the option of abutments that are also angled where they emerge from the gums. These implant components may need to be particularly small or specifically shaped. Because of its lower fracture-resistance, zirconia is not an option for some of these functions, while titanium dental implant components are available, and have proven to be mechanically sound, in a number of versatile options that enhance the personalization of design solutions for complex implant treatments.
Despite the lack of long-term data to support the efficacy of zirconia dental implants in the US, many studies indicate success rates that are comparable to titanium. While titanium implants have stood the test of time, zirconia implants are aesthetically appealing and biocompatible alternatives that have also demonstrated success in many applications. Zirconia implants are the only realistic option for people seeking dental implants that don’t contain metal, and they can be an appealing option for people who want a natural-looking nonmetallic dental implant to address less complicated dental restoration needs.