What is that dark color on my kid’s tooth?
As parents, it is common to be concerned about changes in your child’s mouth. Sometimes you may look and see a dark color gathering and (understandably) panic. Never fear! Just because there is a dark color on your child’s tooth does not mean there is a cavity there, so let’s talk about stains. There are two kinds- intrinsic (from inside the tooth) and extrinsic (caused by something outside the tooth).
Intrinsic stains are most often developmental but can also be due to trauma to the tooth. There are many causes for intrinsic stains. Among these are: 1. Tetracycline-type antibiotic use while the tooth was forming (this is why tetracycline-derived antibiotics have fallen out of favor in patient’s under 12 (or pregnant patients)), 2. Alterations in the formation of the teeth around birth (premature babies or babies that had severe jaundice can have discolored primary teeth) or 3. Color can form after the baby tooth has undergone trauma. In any of these cases, visit your dentist and have them take a look but in *many* cases, you can leave the tooth right where it is to allow it to exfoliate as normal.
Intrinsic stains are the ones you notice immediately, so it can be more jarring to notice a stain which has developed over time because this is often how a cavity would present itself as well. Chromogenic bacteria (that’s right, colorful bacteria!) can be one cause for stains developing on your child’s teeth. The deep grooves in the back molars are most susceptible to this color change because food or bacteria can get trapped there and color can start to develop. Color change alone does not, de facto, tell you there is a cavity on a tooth. A cavity is just that, a hole and an early carious lesion (often associated with color change) can be reversed with good hygiene (though some color change may remain). Stain in the groove of a molar tells you that bacteria (or food, or iron supplements or elderberry syrup) is getting into that groove and causing the color to change, it doesn’t mean there’s a cavity.
If there is only stain but no signs of radiographic decay below it, demineralization around it or softness of the area, I like to be conservative because many of these areas are simply changed color, not a cavity. Why remove color from inside a groove? If there were a stain on a front tooth, you could buff it off with prophy paste, you wouldn’t cut into the tooth to get it off. In my practice, I point out these extrinsic stains to parents and encourage excellent hygiene. I *may* recommend sealing the groove if the patient is high risk but (as with other areas of medicine) it is best to treat the patient as an individual. I like to determine the cause of the stain, investigate risk factors and treat them preventatively if possible. Not every stain on a tooth is a cavity and it is a disservice to our patients to treat them as such.