Sometimes it’s all too obvious that you have tooth decay: You’re in pain or you can see a dark spot on your tooth. But in other cases, you may not even know there’s a problem until you see your dentist.
That’s because your dentist often can find early changes in your teeth that happen before a cavity develops. At first, the tooth loses minerals. Sometimes a chalky-looking white spot appears.
How can your dentist find these early changes that could lead to cavities? The traditional ways are to use X-rays or to examine your teeth by looking at them or probing gently with a dental explorer (pick). If the explorer “sticks” in a tooth, there may be early damage.
Now some dentists are using newer technologies. Do these devices really do a better job than a pair of experienced eyes, an explorer and an X-ray? And if your dentist finds a sign of early decay, does it need to be treated right away?
Digital Imaging Fiber-Optic Trans-Illumination (DIFOTI)®
DIFOTI uses a bright light with a sensor that collects images when it is placed in your mouth. The sensor is connected to a computer that creates an image of your tooth. Areas of the tooth that have lost minerals will appear darker. This is a sign of early decay. DIFOTI images allow dentists to locate early problems. The technique is similar to X-ray but does not use radiation.
Collecting images with DIFOTI takes more time than with X-rays. That’s because the camera has to be placed accurately on each tooth to collect the image. The technology is relatively simple to use. However, a dentist still must interpret the images. This leaves room for differences of opinion.
Your dentist should view these images with caution. A darkened area does not always indicate decay. Your dentist should always look at your teeth along with using DIFOTI.
Digital Imaging: DIAGNOdent®
DIAGNOdent uses a laser. A handheld laser probe is shined on each tooth. The tooth absorbs the laser beam, which leaves the tooth again as fluorescent light. If the tooth is solid, it gives off very little fluorescent light. However, damaged parts of a tooth and bacteria give off more. Information from each tooth is sent to a control unit. This looks something like a digital clock radio.
Studies have found that this technique helps diagnose early decay, particularly in the underlayer of the tooth (the dentin). This layer is just below the hard outer enamel of the tooth. Early decay is often missed because the outer enamel has not broken down and the tooth appears normal. When the dentin is severely decayed, the enamel will break to form a cavity.
DIAGNOdent can also be used to keep track of a suspicious tooth or teeth over time. Its manufacturer says the device is 90% accurate.
Quantitative Light-Induced Fluorescence (QLF)™
Of these three technologies, QLF is the newest. It uses a light source, camera, fluorescent dye and computer software. The camera makes images of each tooth. The fluorescent dye that is used with this camera enables the light source to see areas that have mineral loss. The software analyzes the images. Then it provides information about possible mineral loss. Mineral loss is related to tooth decay.
The technology can detect early decay in primary (baby) and permanent teeth. It also can find early decay that is close to fillings, crowns or braces.
QLF is useful for finding caries in people at high risk of decay. It also can confirm that teeth are healthy in people at low risk. However, QLF is not always correct. It can miss early decay in high-risk people. It also can identify low-risk people as having decay when they really don’t.