Third molar extraction may have positive effect on sense of taste
PHILADELPHIA, U.S.: Taste disorders and other neurosensory defects have been reported postoperatively in a number of patients who have undergone extraction of the mandibular third molars. Although taste deficits are generally expected to resolve within one year, the long-term effects of the surgical procedure remain unknown. A recent study conducted by researchers at the University of Pennsylvania in Philadelphia has challenged the notion that third molar extraction only has negative effects on taste, as it found that patients who underwent the dental procedure had improved taste abilities decades after the surgery.
“Prior studies have only pointed to adverse effects on taste after extraction and it has been generally believed that those effects dissipate over time,” said lead author Dr. Richard L. Doty, director of the Smell and Taste Center at the university, in a university press release. “This new study shows us that taste function can actually slightly improve between the time patients have surgery and up to 20 years later. It’s a surprising but fascinating finding that deserves further investigation to better understand why it’s enhanced and what it may mean clinically.”
The researchers compared data from 891 patients who had undergone third molar extractions (on average two decades earlier) with data from 364 individuals who had not undergone the surgical procedure.
All participants had been tested for chemosensory function at the university’s Smell and Taste Center over the course of the last 20 years. The whole-mouth identification test incorporated presentations of five different concentrations of sucrose, sodium chloride, citric acid and caffeine. Participates had to indicate whether the test solutions tasted sweet, salty, sour or bitter.
It was found that participants who had undergone third molar extraction showed a better overall test score in all four tastes than the control group. In addition, women outperformed men in both groups, and taste function generally declined with age.
“The study strongly suggests that extraction of the third molar has a positive long-term, albeit subtle, effect on the function of the lingual taste pathways of some people,” said co-author Dane Kim, a third-year student in the university’s School of Dental Medicine.
Mechanism remains unknown
According to the researchers, there are two possible explanations for the enhancement of the sense of taste. Firstly, the fact that hypersensitivity can occur after peripheral nerve injury caused by a surgical procedure such as an extraction has already been documented in other contexts. Secondly, damage—caused by the extraction of the tooth—to the nerves that supply the taste buds in the anterior region of the mouth may cause inhibition of the nerves that supply the taste buds in the posterior region, resulting in an increased sensitivity of the entire mouth.
“Further studies are needed to determine the mechanism or mechanisms behind the extraction-related improvement in taste function,” said Doty. “The effects are subtle but may provide insight into how long-term improvement in neural function can result from altering the environment in which nerves propagate.”
The study, titled “Positive long-term effects of third molar extraction on taste function,” was published on June 23, 2021, in Chemical Senses.