Cavities, or areas of decay in a tooth, are the most common dental condition — so much so that most people will have at least one, if not a few, in their lifetime! It’s common knowledge (we hope!) that brushing and flossing are the best defense against cavities and tooth decay, but the reality is that even the most careful brushers can develop cavities simply because teeth have so many nooks and crannies that are difficult to clean completely. Plus, cavities are also virtually undetectable until that toothache occurs, which means it’s gone deep enough to reach the nerve. So, how do dentists find them?
There’s actually no one, foolproof method of finding cavities. Just like it’s hard to brush every single nook of a tooth, it’s also hard for a dentist to see into each and every crevice. So, he or she will rely on three different modes of detection: the visual inspection, the dental explorer, and the x-ray.
During every examination, both the dentist and hygienist do a thorough visual examination of the mouth to look for obvious signs of decay. Some cavities can be big enough to see with the naked eye — you can also often feel these with your tongue or cheek because they’re so large. Otherwise, areas that are discolored to either yellow, brown or black are often indicators that a cavity is in the area.
Next, the dentist will use a tool called a dental explorer to look for cavities that are harder to see. The explorer is a hand tool with a long, thin probe on either end that are usually angled in different ways. The explorer’s thin ends can help the dentist examine narrow areas that are otherwise hard to see and reach. The explorer’s tip will “catch” into cavities that have very small openings and can often help gauge how deep the cavity is.
Finally, the dentist will examine your x-rays to see if there are any additional cavities missed in the visual examination or by the explorer. X-rays are also helpful in showing how deep into the tooth the cavity goes, as well as highlighting any cavities that are on the difficult-to-see sides of the tooth. However, x-rays do have their limitations. Because teeth are so dense, cavities in the middle of the tooth may not show up on the film. Finally, cavities also commonly develop under pre-existing fillings, which usually show up as solid white spots on x-rays. These spots can also block the dentist from being able to see the new cavities during the oral and explorer exam and it can be covered up in the x-ray as well. If left undetected, the cavity can deepen and if left long enough, it can penetrate into the pulp chamber and require a root canal to fix.
Many people are surprised to find out that they have cavities even if they’ve been brushing and flossing carefully. This is in part because most cavities aren’t painful, at least in the beginning, because in the early stages it only affects the enamel and the dentin. As the cavity deepens and gets closer to the pulp chamber and nerves, the cavity will become more painful. Unfortunately, this also means that the cavity will likely need a root canal or other extensive treatment because much of the structure of the tooth has been compromised. So, it’s important to go for your regular dental exams to help stop any developing cavities in their tracks, so they don’t become a bigger and more expensive fix for you later on.
Cavities are practically a fact of life, so don’t feel too guilty if you have one on your next visit. As long as you brush and floss regularly and as thoroughly as possible, you’re doing all the work you need to keep your smile healthy. In fact, regular brushing and flossing can help small areas of decay from developing into full-fledged cavities, so don’t loose heart! If you find that you keep having lots of cavities even with a careful oral hygiene routine, talk to your dentist about whether fluoride treatments or sealants can help you have a healthier mouth. Have you had a cavity recently? Tell us about your experience in the comments!