A dental implant is a screw-like or cylindrical artificial tooth root that is placed within the jawbone to hold a replacement tooth or bridge. The roots are typically made from titanium due to its “excellent biocompatibility,” according to Implant Dentistry: A Rapidly Evolving Practice.
But titanium roots can also include nickel, cobalt, gold and mercury. Although these metals are considered safe for human use, the electrolytes in human saliva may corrode the metals over time, triggering oral allergic reactions.
Studies + Science
A 2018 study found that dental implants can cause symptoms, such as headaches, muscle pain and indigestion, among people allergic to certain metals.
However, sensitivity to titanium, the metal typically used in implants, appears rare, according to a 2006 German paper. The authors found reactions to titanium dioxide in only 4.2% of 700 patients in the study group. (The most common metal allergy was nickel at 68.2%.) A layer of titanium oxide forms naturally around dental implants as the bone heals after surgery, according to a 2017 review of titanium alloys in dental implants.
Whether dental implants cause oral cancer is inconclusive. A 2016 review in the British Dental Journal concluded it was impossible to draw a causal link between oral cancer and dental implants after examining 23 studies. However, study authors cautioned that oral cancer may often be disguised as peri-implantitis, a form of gum inflammation around the implant that destroys gum and bone tissue.
Separately, research in the British Dental Journal suggested improperly done dental implant surgery could cause nerve damage and could lead to problems with pain, speech, eating and kissing, as BBC News reported. More than half of the 30 study participants reported constant pain or discomfort after surgery.
The Food and Drug Administration classifies the dental implant device as an “endosseous dental implant abutment,” meaning it mimics the support of the tooth, used to “aid in prosthetic rehabilitation.” Typically, once medical devices, like dental implants, are approved for use, their manufacturer must continue to report any malfunctions to the FDA through the Manufacturer and Use Facility Device Experience.
MAUDE houses reports submitted voluntarily by manufacturers, health care providers and patients and makes the data publicly available to keep track of device performance and safety issues to help inform providers and consumers.
However, from 1999 to 2019, the FDA ran a program called the Alternative Summary Report. During these years, manufacturers could send spreadsheets listing thousands of cases where devices malfunctioned, rather than submitting individual case details to MAUDE. These summary reports were not made publicly available until June 2019, when the FDA shut down the program and released most of the hidden data, according to a Kaiser Health News report. Kaiser Health News first reported on the secret trove, which included 5.8 million summary reports.
Madris Tomes, a former FDA employee and founder of Device Events, evaluated the 5.8 million summary reports on faulty medical devices using software that analyzes coded FDA report data. Her analysis found 2.1 million of those cases were related to bad dental implants. Of those, 1.5 million or 71% were classified as serious injuries, meaning these injuries should’ve been reported publicly via MAUDE, according to Tomes.
“So these weren’t basic small problems,” she said. The manufacturers “should not have been using the summary program for serious injuries.”
According to FDA guidance, for an event to be reportable as a serious injury, the injury has to be life threatening, result in permanent impairment/damage or require medical or surgical intervention to avoid permanent damage or impairment.
Dental implants were the single most reported implants to the FDA, second only to blood glucose meters, according to a Kaiser Health News report. Since the exposure of the secret database of summary reports, over 300,000 additional adverse reports on dental implants have been submitted to the FDA. Most are from manufacturers, but some come from patients. These reports include individual narrative data that are excluded from the summary reports.
Tomes provided MedTruth with data on adverse reports about dental implants. In the vast majority of cases where the dental implant was rejected, it was labeled as “failed to osseointegrate” or “loss of osseointegration,” meaning the implant could not settle into the bone permanently.
Some reports noted the failure occurred a few weeks to a few months after placement of the dental implant. In some cases, the implant caused the remaining teeth to fail. In addition, cases described reports of pain, burning in the gums, swelling, numbness, as well as mobile implants, with some cases describing penetration of the sinuses. One case report from 2007 stated: “Implants had caused bone loss. Patient was discouraged from suing her dentist as it may be a product issue.”
Searches conducted by MedTruth for reports on "endosseous dental implant" in the MAUDE database for all available years yielded over 500 records, the maximum that the database could yield per search. The records came from multiple manufacturers, many of which are based in Europe.
Specific brands of dental implants have been subject to recall by manufacturers. In 2012, the FDA issued a Class 2 recall for dental implants by the manufacturer Biomet 3i, LLC, for a shallow internal hex. A hex is the internal connection point of the implants, which prevented the driver from fully engaging in the implant. In 2017, the FDA issued a Class 2 device recall for dental implants made by manufacturer Zimmer Dental Inc. for implant vial caps inadvertently cracking. In 2020 alone, the FDA issued 20 recalls for dental implants, or components, i.e., screws and drills, made by the manufacturer Nobel Biocare USA, LLC, in Yorba Linda, California. Reasons for the recalls included incorrect screws that had the potential to loosen and no guarantee of sterilized medical devices.
The FDA released a statement on September 24, 2020, with recommendations for “certain high-risk groups regarding mercury-containing dental amalgam.” In the statement, the FDA warned that certain groups may be at greater risk of potential harmful health effects from “mercury vapor” released from dental amalgams, or the mixture of metals, including mercury, that is used in fillings. The groups at potentially greater risk included pregnant women and women planning on becoming pregnant, children, people with impaired kidney function and those with known heightened sensitivity, or allergy, to mercury or other components of dental amalgam.
The FDA statement mentioned that the release of dental amalgam-related mercury vapor may be highest during placement or removal of the filling. While the statement noted that some people with an allergy to mercury or other amalgam components (e.g. silver, copper, tin, or zinc) may experience health effects, including allergic reactions and ulcers, after placement of an amalgam filling, the agency issued no recommendation for metal testing for patients who may have unknown metal allergies.
The FDA statement also mentioned that the recommendation came on the heels of a “hearing from health care professionals evaluating published literature and considering the public’s comments about dental amalgam and other metal-containing implants.”
The statement made no mention of the 2.1 million summary reports or the 300,000 adverse events reports detailing malfunctioning dental implants.
At least 2.1 million adverse reactions to dental implants have occurred in the last 20 years — although these reports were hidden from public view until recently.
Of those, 1.2 million were classified as serious injuries and another 300,000 detailed narratives have been added in just the last two years.
Reports of side effects from dental implants include the failure for the dental implants to osseointegrate, as well as pain, burning, swelling and numbness. The FDA released a statement warning of adverse side effects from dental amalgam in Sept. 2020. Patients can voluntarily report adverse events from dental implants and other medical devices on their page for reporting serious problems with FDA-regulated products here.
Currently, major professional dental organizations, like the American Dental Association and the American Association of Oral and Maxillofacial Surgeons, maintain that dental implants are a safe and long-term solution for missing teeth. The ADA, however, suggests that patients with chronic illnesses, like diabetes, may not be suitable candidates for the implants. The AAOMS does not mention metal allergies or the potential for side effects from dental implants on its website.