Many things get stuck in our teeth - caramel, popcorn, spinach - but did you know that for some workers, evidence of their job can get stuck in their teeth, too?
A team of scientists at Gujarat, India’s Gujarat Forensic Sciences University, under the helm of forensic odontology student Dr. Riddhi Thanki, Rajesh Babu and Dr. MS Dahiya, found a connection between the hardened plaque deposits found on teeth and certain environmental factors.
Known as dental calculus, that hardened plaque dental hygienists remove every six months may have some stories to tell about the lifestyle of the mouths it originates from. That’s because that calculus can harbor some very interesting elements besides just the usual suspects.
"The researchers found that in addition to the regular materials we typically find in dental calculus, such as calcium phosphate from saliva and bacterial remnants, elements we may be exposed to in nature can also become part of our dental calculus," says Dr. Martin Abelar, a dentist from San Diego, California.
To test this theory, Thanki and his team examined the dental calculus from workers at a thermal power plant, a coal yard and a shipping yard. They cross-checked local soil samples with the calculus removed from the teeth of a total of 135 workers and found many of the same elements present in both the workers' mouths and the soil.
"In the samples from the soil and the workers' teeth at the shipping yard, the scientists found silicone, neodymium and ytterbium," Abelar says. "At the coal yard, they found chromium in both types of samples. Basically, if it was in the soil, it was also present to some degree in the dental calculus, too."
So, why study the components of someone’s dental calculus, anyway?
"Information like this can have a wide array of uses," Abelar says. "It can help determine if an individual is being exposed to an unsafe level of an element. In forensic cases where the person is deceased, it can help determine cause of death, or even possibly the geographic region the person was from, which can help identify a body or narrow down the search for the origins of a John Doe."
Abelar says while this type of very specific research is not being utilized in America quite yet, it could be very helpful in some situations.
"I think there’s a narrow scope for which this can be used, but it will be very useful in those situations," says Abelar. "You’d be hard-pressed to find a situation where more information was a bad thing."