A black spot or stain on a tooth: decay or staining? Causes and treatment
A black spot on a tooth makes most people think of decay first. Decay can indeed look black or brown, but staining in the grooves of molars, tartar, old metal fillings, a darkened tooth after a knock and bacterial stains in children can look similar. Only an examination and, where needed, an X-ray show which it is. Below we cover the most common causes and how each is handled.
Possible causes of a black spot
| Cause | Where it appears | Clue |
|---|---|---|
| Decay | Molar grooves, between teeth, at filling edges | Soft surface that catches; may be sensitive to sweets and cold |
| Arrested (inactive) decay | Usually molar grooves | Hard, shiny dark spot that hasn't changed for years |
| Tea, coffee, tobacco staining | Grooves, gum line, between teeth | Superficial; usually polishes off |
| Tartar | Inner surfaces of lower front teeth, gum line | Rough, hard deposit |
| Old amalgam filling | The filling and surrounding tooth | Grey-black shadow |
| A tooth whose nerve has died | Usually a front tooth after a knock | The whole tooth turns grey-brown |
| Black stain in children | A thin black line along the gum | Bacterial staining, not decay |
Decay or not?
Decay starts as a chalky white spot and over time turns brown and black. If the surface has softened and an instrument catches in it, the decay is active. Some decay hardens and stops over the years; it's dark but hard and shiny, and often only needs monitoring. Decay between teeth may not be visible from outside and needs an X-ray. Details: signs and stages of tooth decay, decay between teeth.
Staining and tartar
Tea, coffee, red wine and smoking leave dark stains, especially in the deep grooves of molars and at the gum line. This staining isn't decay and largely polishes off at the clinic. Tartar forming below the gum line can look black when mixed with blood and causes gum inflammation; it's removed with a scale and clean. For overall discolouration, see why teeth turn yellow.
Old fillings and darkened teeth
Old amalgam fillings darken over time and can give the surrounding tooth a grey shadow. If the filling is sound, that alone isn't a reason to remove it; if there's decay or a crack at its edge, it's replaced. See should amalgam fillings be removed.
A front tooth turning grey months or years after a knock can mean its nerve has died. Such teeth first need root canal treatment; the colour can then be corrected with internal whitening or a crown. See dental trauma.
Black stain in children
Some children have a thin, dotted black line along the gum line. It's usually staining from certain mouth bacteria, not decay, and is often seen in children with low decay risk. It polishes off at the clinic but can come back. Iron supplements can also darken teeth; giving the syrup through a straw and rinsing afterwards helps. For decay in baby teeth, see baby bottle tooth decay.
Treatment options
- Polishing and professional cleaning: For staining and tartar.
- Fissure sealants: To protect deep grooves that aren't decayed. See fluoride and fissure sealants.
- Filling: For active decay. See white fillings.
- Root canal plus internal whitening or a crown: For darkened teeth whose nerve has died.
- Monitoring: For hard, unchanging arrested decay.
Examination in Beylikdüzü
At Dent32 we determine with an examination and, if needed, an X-ray whether a spot is decay, and suggest only the treatment that's needed; we don't fill stains.
Dent32 Ağız ve Diş Sağlığı Polikliniği (Dent32 Dental Polyclinic) is at Barış Mah., Ginza Lavinya, E-5 Yanyolu No:30 D:179, 34520 Beylikdüzü, Istanbul and is open seven days a week. To book, call or WhatsApp +90 555 011 33 68, or use our contact page. At the examination we share the findings, the options and the approximate cost in writing; you are under no obligation to start treatment afterwards.
For clinic details, our dentists and the full list of treatments, visit Dent32, dental polyclinic in Beylikdüzü.
Frequently asked questions
Will a black spot come off with brushing?
Surface staining may fade a little, but staining in deep grooves and decay won't brush off. An examination is needed to tell what it is.
Does a black spot need treatment if it doesn't hurt?
Decay doesn't hurt at first. A soft or growing spot needs treatment; hard, unchanging spots can be monitored.
My child has a black line on their teeth. Is it decay?
A thin black line at the gum line is usually bacterial staining, not decay. It's still worth having it checked at an examination.
