Dental implants have become a popular and effective solution for replacing missing teeth. While they offer numerous benefits and improve oral health, it’s essential to be aware of potential long-term side effects. One such side effect is metal hypersensitivity, an allergic reaction to certain metals used in dental implants. In this article, we will delve into the details of metal hypersensitivity, its symptoms, and how it can impact the long-term success of dental implants.
Metal Hypersensitivity: A Closer Look
Allergies are hypersensitivity reactions that occur when the immune system overreacts to substances that are typically harmless. Metal hypersensitivity, in the context of dental implants, occurs when the body reacts negatively to metals like titanium, commonly used for implants. Interestingly, titanium is also found in everyday objects we come across, such as watches, jewelry, coins, and even cosmetic products like sunscreens [24, 25].
The symptoms of metal hypersensitivity can range from chronic inflammation and pain to chronic fatigue, depression, and even fibromyalgia. Oral lichenoid lesions, characterized by lichenoid reactions, are a common presentation in patients with metal hypersensitivity . These symptoms usually occur in individuals who are chronically exposed to metal allergens due to their implants. However, it’s worth noting that metal implants can be rejected in the absence of previous hypersensitivity reactions .
Understanding Metal Hypersensitivity
Metal hypersensitivity falls under type IV hypersensitivity, known as delayed hypersensitivity. This means that the allergic reaction takes around 48 to 72 hours to develop [24, 25, 28]. The initial exposure to a metallic antigen triggers a response involving Langerhans dendritic cells and TH-lymphocytes. When the patient encounters the metallic antigen again, TH-lymphocytes activate macrophages, leading to inflammation as a defense mechanism . This immune response can potentially cause tissue damage and even result in implant failure .
Exposure to metals from dental implants, amalgam fillings, or joint prostheses can lead to serious health problems [24, 25, 27]. To determine if metal hypersensitivity is a concern, sensitive patients can undergo the Memory Lymphocyte Immunostimulation Assay (MELISA®) test. This blood test isolates TH-lymphocytes from a patient’s blood sample and tests their reactivity to different metals. The MELISA® test is especially useful for patients experiencing symptoms of metal allergy but have had negative patch tests .
Managing Metal Hypersensitivity
In the case of dental implants, trace amounts of other metals, such as aluminum or nickel, may be present alongside titanium. These additional substances enhance processability and prevent corrosion [25, 30]. Dental fillings, bridges, and even sunscreens can contain metals like nickel, aluminum, and titanium, making them potential sensitizers [24, 31]. It is crucial to identify which metals a patient is exposed to and establish a list of potential allergens based on their dental and medical history, as well as environmental factors . Removing other potential allergens, such as amalgam fillings and metal bridges, can be beneficial in reducing metal-specific reactions .
Individuals with a history of allergies to metals have a higher risk of developing hypersensitivity reactions to metal implants . For sensitive patients, there is no safe limit or acceptable level of exposure to certain metals . Therefore, before placing permanent implants, it may be advisable for individuals with a history of allergies to undergo metal allergy assessment and testing to prevent implant failure due to an allergic reaction to titanium [9, 30]. The MELISA® test can help identify which metals are tolerated by the patient and which may trigger an unwanted immune response [29, 33].
By understanding the potential risks associated with metal hypersensitivity, patients can make informed decisions about dental implant procedures. Seeking professional guidance from a qualified dentist and undergoing necessary tests, such as the MELISA® test, can help ensure the long-term success and overall satisfaction of dental implant treatments.
Remember, your smile is precious, and prioritizing your oral health is essential. To learn more about dental health and explore various treatments that can make you smile, visit Make You Smile.