Antidepressants are the third most common prescription drug taken by Americans. These drugs offer significant help with anxiety, depression, pain, and other disorders. However, new research from the University of Buffalo shows that antidepressants also appear to quadruple the risk of tooth implant failure in patients who are taking them.

Members of the Buffalo team, headed by Sebastiano Andreana, associate professor and director of the implant program at the University of Buffalo School of Dental Medicine, undertook a pilot study after he and other practitioners noticed an increasing number of their patients reporting using antidepressant medication. The Buffalo study builds upon the work of a 2014 study in the Journal of Dental Research that showed a link between selective serotonin reuptake inhibitor, or SSRI, antidepressants and increased risk of bone fracture, which influences dental implant failure.

For this pilot study, out of a target population of 1200 patients, the Buffalo team, which includes Andreana, Sulochana Gurung, a doctor of dental science (DDS) student, and Latifa Bairam, a professor of restorative dentistry, reviewed 75 charts for their study. The average age at implant placement of the patients was 62, and there are more women with implant failures than men. They took into account patients’ history of smoking, alcohol use, medications including antidepressants, thyroid conditions, diabetes, osteoporosis, and HIV, among others, and counted an individual implant as a single failure.

“The frequency of antidepressant use was higher in patients who had failure—33 percent, versus 11 percent in patients who did not take antidepressants,” Gurung tells mental_floss. What's more, he says, “Each year of antidepressant use was associated with twice the increased odds of implant failure.” 

While they did not screen for specific antidepressants, they found the correlation between implant failure and antidepressant did not differentiate between kinds of antidepressants. Future research will include trying to determine whether different classes of antidepressants have different degrees of risk.

Andreana does not want to discourage anyone from taking necessary antidepressant medications, but he feels it is important that patients know the risks if they are having dental work. “SSRIs are a good thing, but they have an inhibitory effect on osteoblasts, bone cells, which we’ve only known about since 2010,” he tells mental_floss. This effect is more significant, he says, when bone cells are under a load. “This is why we think the implants under a crown or bridge are more predisposed to bone loss, because of the inhibiting effect,” he says. 

Besides inhibiting osteoblasts, other SSRI side effects that are of concern to dentists include: osteoporosis, which weakens bones and makes them brittle; akathisia, a syndrome of restlessness, which can include shaking of the head and jaw; teeth grinding, also known as bruxism; and dryness of the mouth, all of which can have detrimental effects on the dental implant healing process.

“Antidepressants were never a focus of our attention for the majority of dentists, but with the past five years of research, we’re now looking at it from a different perspective,” says Andreana.

Gurung presented these findings at the 45th Annual American Association for Dental Research in March. The researchers will now retest their results with a larger sample size to strengthen their results, and are working on an article for peer review.