Losing Your Teeth, and Your Mind? - A brainy reason to visit your dentist.

I've taken out my wisdoms teeth. May be it wasn't that wise to pull them out?

A post from psychologytoday.com by Joshua Gowin has the whole story. Here is a part:

A team of Japanese neuroscientists may have bitten off more than they could chew.  Or at least more than their research participants could chew.  There may be some truth to the stereotype of the slow-witted toothless guy.   According to their study, having fewer teeth may mean having a worsememory.  Time also plays a role; the longer a person has been toothless, the more likely they are to experience cognitive decline.  Now might be a good time to start following your dentist's advice about regular flossing.

Nozomi Okamoto and his collaborators were interested in parsing out which factors might predict memory decline as we age.  The gums might not seem like the first place to look for brain power, but past research has shown that periodontal disease is associated with the development of dementia.   In a rat model, removing the rodent's teeth resulted in decreased chewing, but peculiarly it also led to fewer brain cells in the hippocampus and a reduction in the brain chemical acetylcholine, two markers of Alzheimer's.  Some evidence suggests that inflammatory agents originating from gum disease may lead to inflammation in the brain.   Might dental health be an indicator of mental ability? Okamoto recruited over 4,000 participants over age 65 from the Nara region of Japan, just south of Kyoto.  Okamoto assessed participants for MMI, or Mild Memory Impairment, a preclinical stage of dementia.  He also had two dentists screen them to count the number of remaining teeth and, for toothless subjects, the length of time without teeth.  To account for other possible explanations of memory function, Okamoto also tested for level of depression, typical alcohol intake, smoking habits, lifestyle, education and medical history.
Even when controlling for other factors such as education and lifestyle, having fewer teeth was a significant risk factor for performing worse on memory tasks and demonstrating MMI.  Participants who had been toothless for over 15 years were three times as likely to have MMI compared to their toothy peers.   Now we know why they're calledwisdom teeth.