Why do baby teeth turn dark?

Decay is the most common explanation

Most dark spots start out as something far less dramatic, a dull white patch where the enamel has begun losing minerals. Left alone, that patch can progress to brown and eventually to a dark brown or near black as decay works deeper, especially in the grooves of back teeth or the tight spaces between them, where it is easy to miss until the color changes. By the time a spot looks obviously dark, decay has usually been active for a while.

This is the version prevention is built around. Fluoride treatments and BPA-free sealants both work on exactly this kind of vulnerable spot, and routine checkups exist so a dark patch gets caught while it is still small rather than after it has spread.

Two other causes worth knowing about

An old bump or fall is the second most common story. A hard knock can affect the blood supply inside a tooth, and in the days or weeks afterward the tooth can darken toward gray, brown or even a deeper shade, sometimes with no chip or crack to point to. If that sounds like what you are seeing and you remember an injury, even a minor one from a while back, mention it when you call.

The third cause is plain surface staining, which is not decay at all. Certain liquid vitamins or iron supplements can leave a stain on the outside of a tooth, and so can a layer of plaque that has hardened into tartar along the gumline. Staining tends to sit on the surface and can often be lifted at a professional cleaning, while decay sits underneath the enamel and needs treatment, not a toothbrush.

When to stop watching and call

Call rather than wait for the next routine visit if you notice any of the following: a dark spot that seems to be spreading or growing, one that has an actual dip or soft feel to it, darkening that shows up after any bump to the mouth, or discoloration alongside swelling, pain, or a tooth that seems to be sitting differently than before. When in doubt, call and describe exactly what you are seeing.

Our front desk fields this question often, and one call sorts out whether it is worth a look this week or can wait for the next checkup: (239) 482-2722. A true emergency, trouble breathing, heavy bleeding, a head injury, goes to 911 or the emergency room first, ahead of any call to us.

What actually helps while you wait for the visit

Keep brushing the area gently with your normal routine. Scrubbing harder to try to remove the color will not work and can irritate the gum around it. A photo taken in natural light is genuinely useful at the appointment, since color can be hard to describe over the phone, and it helps to jot down roughly when you first noticed it and whether any fall or bump came before it.

What you will not find here is any home remedy for whitening a discolored baby tooth. That is not something to try on your own, and it is exactly the kind of question our front desk is glad to answer directly rather than leave you guessing. More on the repair options a dark tooth might need is on our restorative dentistry page.