Dental Implants Metal Allergy
Rapidly becoming the most popular solution for replacing one or more missing teeth, dental implants provide results that are the closest to a natural tooth currently available in dentistry. This is because dental implants replace both the visible crown and tooth roots via metal rods imbedded directly into the jawbone. Since the devices are often made out of titanium, people with metal allergies often wonder if they are candidates for the procedure. Luckily, a metal allergy generally does not prohibit someone from getting dental implants.
Metal Allergy: An Overview
Metal allergies occur as an overreaction produced by the body’s immune system in response to a foreign material. The responses range in severity from something as mild as a skin rash to something life-threatening like organ failure.
Most allergies are caused by specific types of metals. Nickel, for example, produces allergic reactions in approximately 17% of women and 3% of men. Cobalt and chromium also produce reactions though in lower percentages. Often, a reaction to metal occurs from external contact between jewelry or metal and the skin causing a rash. More serious reactions can happen when replacement body parts are made of metal as the body may reject the device
Metals, particularly the dental amalgam used in fillings, have long played an important role in dental treatments. Dental amalgam combines precious metals like gold or silver with other metals including copper, tin, and traces of mercury. Although safely used for decades, dental amalgam has been associated with rare instances of inflammation or rashes.
The most common metal used to manufacture dental implants from is titanium. Commercial titanium has superior biocompatibility with bone and as such, is highly regarded for dental and medical treatments. Bone cells can grow on and adhere to titanium easily which aids in strengthening the bond between the implant and jawbone. Even for patients with metal allergies, titanium rarely causes issues with dental implants. It is so rare, that less than 1% of implant patients who participated in one clinical study reported any adverse reaction to the metal.
Titanium Allergy: Symptoms and Testing
In some cases, people may not be aware they have a titanium allergy. Symptoms commonly associated with an allergy to titanium include:
- Erythema – redness of the tissue around an implant
- Urticaria – bumps or hives which develop on the gum or skin surfaces
- Eczema – inflammation and itchiness of the skin or gums
- Swelling, discomfort, or formation of sores in the mouth
- Necrosis – cells or tissue around the implant dies
- Bone loss
- Areas of dry gum tissue
Fortunately, diagnostic tests, like patch tests, can be conducted by dental professionals ahead of time for any patient that suspects they could be allergic to the titanium found in their implants. Some doctors could also recommend in vitro blood tests such as the lymphocyte transformation test, lymphocyte migration inhibition test, and the MELISA test to diagnose an allergy to titanium. Blood tests such as these isolate white blood cells, expose them to titanium, and measure how the immune system reacts to the exposure. Compared with traditional allergy tests that rely on skin patches, MELISA tests offer a higher degree of accuracy and are therefore the recommended type of test to undergo prior to implant surgery.
Non-Metal Alternatives to Titanium Dental Implants
Having read so far, patients who know they have a titanium allergy may think they are not suitable candidates for implants. Fortunately, modern advancements in dental technology and materials have led to alternatives that can be used in dental implants instead of titanium.
Developed in 1987, zirconia is one such material that is now frequently used in dental implants. Classified as a ceramic, the non-metallic alternative is suitable for patients that are allergic to metals like titanium. Corrosion resistant, zirconia is strong, very durable, and bonds well with bone. As such, anyone seeking dental implants but are concerned with an allergy to metal may find zirconia a great alternative.
Zirconia implants offer several benefits including:
- Contain no metal thereby reducing risk of allergic reaction
- Very strong
- Corrosion resistant
- Hygienic – less plaque accumulation
- Better appearance – zirconia is white and therefore no dark material will show through the gums
Drawbacks of Zirconia As Opposed to Titanium
Despite its many benefits, zirconia does have some limitations or drawbacks when compared to titanium. Amongst the drawbacks associated with zirconia are:
- Less Component and Design Options Available: Whereas titanium has been in use for several decades, the development of zirconia implants is still somewhat new. Vital design changes, such as two-piece screw-retained abutments, have only been options in the United States since 2019. As of now, there is a greater variety of component and design options for titanium systems vs zirconia. This is particularly true if multiple teeth, or an entire set of upper or lowers, need replacement. Should a single tooth need replacement, zirconia is generally not a big worry.
- Long-Term Effectiveness Questionable: Backed by several decades of clinical research and development, titanium has a proven track record of effectiveness for use in dental implants. In fact, titanium has shown to have a long-term success rate of up to 98%. On the other hand, zirconia has not been in use as long which makes its long-term effectiveness and risk for potential complications less well known.
- Fracture and Strength Resistance: Compared to zirconia, titanium is less brittle and has higher fracture and flexural strength. Although strong under compression, zirconia is more likely than titanium to fracture under flexing or bending forces. Because of this, zirconia is more susceptible to fracture and complication in the long run.
- Not Suitable for Complex Cases or Implant-Supported Dentures: Typically, zirconia systems are not suitable for patients that are missing all their teeth or those replacing them with implant dentures. These types of treatments require significant amounts of planning and need to have a wide range of component choices. Given the greater number of component purpose, size, and angulation options offered by titanium implant systems, they are suitable for even the most challenging cases. Zirconia, on the other hand, has fewer options with limited versatility.