We all know what cavities are. Cavities can be simply defined as a hole on the surface of the tooth. The cavities are tooth decay and they occurs when the bacteria in the dental plaque (or sticky food debris) on the tooth surface produces acids that melts away the tooth surface structure. We know that if we eat candy or food high in sugar content, the bacteria on the tooth will grow and they will produce acid to damage the tooth surface and overtime, the cavities are formed.
But how do dentist find out if we have dental cavities? At the dentist’s disposal, several tools will help detect the presence of cavities. These tools are xray images, intraoral mirror, a dental instrument called the dental explorer, tooth decay detection dyes, etc.
Dentist uses explorer instrument to check for cavity.
The most obvious tool is the intraoral mirror and dental explorer. By visual examination, the healthy tooth surface is white and smooth. If there is a darken spot is noticed, dentist will then use the tip of dental explorer to test the darken spot. If the darken spot is sunken and the texture feels soft and as dentist tries to pull out the tip of the dental explorer, the dentist will feel there is a “catch”. If the clinical examination shows the darken area on the surface of the tooth fulfills these criteria, then the dentist can say the area are dental cavities.
Dental Xray image shows tooth cavity. The darkened area pointed by the arrow is the location of the tooth cavity.
In some area of the tooth, dental instrument cannot be reached into those area, for example, the side in-between the two teeth. Then the dentist can use the xray image to detect any changes in densities in the tooth structure. Around each tooth there is a outermost layer of enamel and is usually more dense in structure. A dense area will show up as white area in xray image. However, when there is a cavities within the surface of the tooth, the outermost layer will be compromised. On the xray image, it will show up as what’s called the radiolucency area on the tooth. This is how dentist detect the cavities with the xray.
Sometimes, dentist can use a tooth decay detection dye. This is a special dye that will changes color when it touches an area with specific kind of bacteria or reacts to the acid released by the tooth-decay-causing bacteria.
In my office, I routinely use all these tools to help detect tooth cavities for my patients. I will also use an intraoral camera to show pictures to my patients so that they can see exactly where the problem is.
Written by Daniel Tee, DDS, MS
Practicing Dentist Serving Tempe, Chandler, Phoenix, Mesa, and Gilbert Arizona