Life

Ask the Dentist: Sometimes it can be difficult to pinpoint the root of a toothache

Lucy Stock, dentist at Gentle Dental Care in Belfast, says experiencing pain can sometimes be a case of crossed wires

It can be hard to say exactly which tooth is the source of your pain
It can be hard to say exactly which tooth is the source of your pain

I’M SURE you don’t consider yourself lucky if you can pinpoint exactly which tooth hurts. However, you are because quite often a patient is simply unable to say which tooth is the offending tooth, something that, understandably, makes treatment more complicated.

Tooth pain can be a tricky character. It can wander from the top teeth to the bottom teeth or even if the pain is actually originating from one tooth the adjacent teeth can feel like they are all involved in the crime.

On the whole, we are pretty good at identifying the exact body part that is giving pain, like if we cut a finger or scratch part of a leg, but when it comes to teeth it’s just not so straightforward.

And it’s all to do with how the brain is wired. An experiment was done at the University of Erlangen-Nuremberg in Germany in which brain activity in healthy volunteers was analysed. Electrical currents were zapped through an upper and a lower tooth on the same side and then the brain activity was mapped. It turned out that pain from both teeth lit up the same parts in the brain.

So basically, whether it was the upper or the lower tooth sending pain signals, the brain didn’t really register much difference. And if our brains can’t tell the difference, then neither can we.

“The activation was more or less the same and there are physiological and anatomical reasons for that,” lead scientist Clemens Forster said, although he added that the experiments might have missed subtle differences that could account for why some tooth pain can be localised.

Other conditions can also complicate diagnosing where pain is coming from. For instance, if your upper teeth are painful and your nasal passages are congested or tender, your toothache may be due to sinusitis. The upper teeth roots lie close to the sinuses, and if your sinuses are inflamed due to an infection, you may feel the pain in your upper teeth.

A serious but less common source of referred tooth pain is the vagus nerve, which passes near the heart and lungs. Before it reaches the brain, the vagus nerve also passes through the lower jaw. Consequently, a toothache is occasionally a sign of a problem with the heart or lungs.

Dentists can tell a lot from listening to the history or pain, examination and x-rays but sometimes due to the underlying causes, pain can be difficult to determine the exact culprit.