Black Teeth: What the Dark Spots Mean and What Removes Them

You've spotted something dark on a tooth, and now it's the only thing you can see when you look in the mirror. Here's the calm version before anything else: black on a tooth is nearly always one of four perfectly ordinary things, and every single one of them has a straightforward fix.

The Four Reasons a Tooth Goes Black

Nearly every dark tooth we get shown comes down to one of four things, and they're easier to tell apart than you'd think.

The first is stain sitting on the surface, which is the most ordinary of the four and the least serious by a long way. The second is tartar along the gum line, which is hardened plaque that has taken on a dark colour from where it sits. The third is decay, which is the one everybody fears, and it's the only one of the four that's actually a hole in the tooth. And the fourth is a tooth that has died on the inside, which darkens from the middle outwards while all its neighbours stay exactly the shade they always were.

Three of those four sit on the outside of the tooth, and only one is a hole. So the real answer is usually gentler than the version people picture on the walk to the mirror.

Surface Stain: the Kind That Sits On Top

Let's start with the happiest one, because it's also the likeliest.

Think of the inside of a mug you've been drinking tea from for years. There's a brown ring in there that washing-up liquid never quite shifts, and it isn't damage to the china. It's tea that has settled on the surface and built up layer on layer. Teeth do the same thing, because enamel is far less smooth than it looks, so the pigment in tea, coffee, red wine, dark sauces and tobacco finds plenty to hold onto.

A couple of everyday things build that stain faster. Liquid iron supplements leave a dark stain of their own, which is why the advice is usually to drink them through a straw, and the strong antiseptic mouthwashes sold for gum problems can turn teeth brown over a few weeks of steady use.

The tell for surface stain is that it's spread out rather than a single spot. It's usually on several teeth at once, worst where a brush struggles to reach, and brownish-black rather than truly black. The good news is that it lifts off. A professional clean at £100 takes the whole lot away, because the polishing stage does to your enamel what a proper scrub does to that mug.

Black Tartar Along the Gum Line

This one confuses people more than the others. It looks alarming, it feels like it ought to be decay, and it almost never is.

Plaque is the soft film that forms on teeth all day long. Leave it sitting and the minerals in your saliva set it hard, the way water leaves limescale inside a kettle, and that hardened version is tartar. No brushing shifts it once it's set, which is why it takes a hygienist to get it off. Our guide to tartar removal and the first hygienist appointment walks through that visit, and it's a gentler hour than its reputation suggests.

The colour is the interesting bit. Tartar above the gum line comes off creamy or yellowish. Tartar that has crept below the gum line comes off much darker, brown through to black, because down there it sits against a gum that's a little inflamed and bleeds very slightly when disturbed, so it takes up the colour of that blood the way a tea towel takes up a spill. The black you're staring at is a stained deposit sitting on the tooth, not a mark in it.

The tell is the shape. Tartar follows the line of the gum like a tidemark on a beach, usually across several teeth at once, and it's often worst behind the lower front teeth, because there are saliva glands right underneath there, and more minerals landing means it sets faster.

The fix is a clean at £100, and where it has gone further under the gum, deep cleaning at £150 to £180, done with the area numbed first so you feel pressure rather than pain. If your gums have been bleeding when you brush as well, our gum disease treatment page lays out the stages and what each one costs.

Decay: the Black That's a Hole

This is the one everybody assumes it is, and it's worth understanding properly.

The bacteria living on your teeth feed on sugar and leave acid behind. That acid dissolves minerals out of the hard outer shell, and once it reaches the softer layer underneath, that layer breaks down much faster and stains dark as it goes, the way the bruised part of an apple turns brown while the rest stays white. So the black of decay is a black you could put the tip of an instrument into.

The tell is that it's one spot, on one tooth, rather than a spread. It usually sits in a groove on a biting surface, or between two teeth where a brush has never properly reached. The tooth might have started twinging at something cold or sweet, and floss can catch on it, because there's a lip of surface that has given way.

Here's the honest twist, though, and it's why nobody should settle this in the bathroom mirror: a dark line down a deep groove is very often just stain that has collected in a crevice, with completely sound tooth underneath. From a foot away the two look almost identical. What separates them is a probe and an X-ray.

When it is decay, the repair depends on how far in it has got, and our guide to the stages of tooth decay and the fix at each one follows that the whole way. A small one is a filling at £149 to £349. A bigger one, where there's not enough tooth left for a filling to hold onto, is a crown at £650 to £895, which caps what remains and takes the bite force so the tooth carries on working. And if the decay has reached the nerve, root canal treatment from £399 clears the infection and keeps your own tooth in place. If what you're really asking is whether a tooth this dark can be saved at all, rotten teeth and what has to come out answers that tooth by tooth.

A Tooth That Has Died: the Black That Comes From Inside

The fourth one has a very particular look, and once you've read the description you'll know whether it's yours. A single tooth has gone grey, brown or nearly black, while every tooth around it has stayed exactly the colour it always was.

That's a tooth whose inside has stopped living. There's a soft core in the middle of every tooth holding the nerve and a tiny blood supply, and it can give up after a knock, sometimes years later, or after decay or an old filling has sat too close to it. The hard outer tooth carries on standing perfectly well, so people go years without noticing a thing. What changes is the colour, because pigment from that old blood supply seeps outwards from the middle, soaking in the way red wine soaks into a tablecloth from underneath instead of sitting on top.

That "from the inside" part is why the fix looks different from the other three, and we've written the full picture of how long a dead tooth can stay in your mouth if that's the one you think you're looking at. The short version is that root canal treatment from £399 deals with the inside, cleaning out that empty space and sealing it so bacteria can't gather there, and a crown at £650 to £895 is usually the sensible finish afterwards. It protects a tooth that has been hollowed out, and on a front tooth it hands back a colour matching the ones either side.

How a Dentist Tells Them Apart

Here's how somebody sorts your particular one into the right box, and there's far less to it than you'd imagine.

First, the look. Is it one tooth or several? Does it follow the line of the gum, or sit in the middle of a tooth face? Are its neighbours a normal colour? That alone usually takes four possibilities down to two. Then the feel: stain and tartar sit on a hard surface, so an instrument runs across them without catching, while decay is soft, and that softness is the giveaway nothing else shares.

Then the X-ray, which settles it, because it shows what no amount of looking can. Decay appears as a shadow eating into the tooth beneath the enamel, so we can see straight away whether it's shallow or most of the way to the nerve. A tooth that has died often shows a darker patch at the very tip of its root, where the body has quietly been walling the area off. And a tooth that's dark purely because it's stained shows nothing at all, which is its own kind of answer, and a nice one to give.

At UrgentCare Dental that first look is £20. A dentist goes over the whole mouth, takes the digital X-rays your tooth calls for, and tells you plainly what's there and what would put it right. Anything that needs doing is priced in writing first, and you choose whether it happens that visit or another day. Every figure sits openly on our price list so you can read it before you ring. And if the gum beside that dark tooth has swollen up, come in the same day rather than waiting, because swelling settles fastest when it's caught early.

Why Whitening Doesn't Fix Most of This

Now for the question a fair few of you came here carrying, and we'd far rather answer it straight than sell you something that wouldn't work.

Whitening gel does one job: it breaks apart pigment caught in natural enamel, working from the outside in. That's brilliant against surface stain, and it's why years of tea and coffee lift away so satisfyingly. Hold that up against the other three causes, though, and the problem shows itself.

Whitening can't touch decay, because decay is missing tooth rather than colour, so there's nothing there for the gel to lighten, and putting bleaching gel over an open cavity is a good way to have an uncomfortable evening. It can't take tartar off either, because tartar is a hardened deposit that has to be physically removed, and bleaching it would only leave you with a paler lump in the same place. And it can't reach a tooth that has died, because that colour travels from the inside outwards while the gel works from the outside inwards. The two never meet in the middle.

Worth knowing before anybody buys a kit: whitening only works on natural enamel, so crowns, veneers and white fillings stay exactly the shade they are, and brightening the teeth around them leaves the colours mismatched.

So the order matters, and it's the same every time. Get the mouth healthy first, then talk about colour. Once the decay is filled and the tartar is off, a great many people find their teeth already look brighter than they expected, because a proper clean carries the stain away with it. If you still fancy going brighter, a take-home kit from a dentist is £349, and our honest guide to what teeth whitening costs walks through the whole market.

What a Black Tooth Costs to Put Right

Here's the whole thing in one place, since money is what keeps people out of the chair longest.

Those are guideline figures for a straightforward case. You get your own figure in writing once a dentist has seen the tooth, settled before a single thing is started, so nothing can creep onto the bill afterwards.

And if there's more than one thing going on in there, which is perfectly normal when it's been years, it gets done in an order rather than all at once: whatever hurts or is infected first, then the cleaning and any gum treatment, then the fillings and the bigger repairs, then a check that it has all settled. For most people that's four or five appointments to get the mouth stable, and what a dental stabilisation plan is lays the whole road out. After that it's six-monthly check-ups and a clean, or a care plan from £19.99 a month, and the point of that rhythm is that nothing gets the chance to go dark in the first place.

Common Questions About Black Teeth

Can black teeth be whitened?

Only where the black is stain sitting on the surface, and in that case yes, very effectively. Whitening gel breaks apart pigment caught in natural enamel, so tea, coffee, wine and tobacco staining lifts beautifully. It does nothing for decay, which is missing tooth rather than colour, nothing for tartar, which has to be physically taken off, and nothing for a tooth darkened from the inside, since the gel only works from the outside in. Get it looked at first, because a clean alone often does more than people expect.

Does a black spot on a tooth always mean decay?

No, and that's one of the more cheering things we get to say. Plenty of dark spots turn out to be stain collected in a deep groove, with sound tooth underneath, and from the outside the two look almost identical. The difference is that decay is soft and casts a shadow on an X-ray, while stain is hard and shows nothing at all, so X-rays come with the first appointment for exactly this reason.

Why has just one of my teeth gone black?

A single dark tooth with normal-coloured neighbours nearly always means that tooth's nerve has died, and the pigment is seeping outwards from the inside. The usual cause is an old knock, sometimes from years earlier, or a deep filling that sat too close to the nerve. It isn't an emergency on its own, and it doesn't mean losing the tooth, because root canal treatment cleans and seals the inside while a crown can restore the colour.

Can you get black tartar off at home?

Not really, and that isn't a failure of effort on your part. Tartar is plaque that has set hard with the minerals in your saliva, the way limescale sets inside a kettle, and once hardened a brush polishes it rather than removing it. The black kind is trickier still, because it has usually formed below the gum line where nothing you own can reach. A hygienist lifts it away in a single visit at £100.

How much does it cost to fix a black tooth?

It depends on which of the four it turns out to be, and that's why the look comes first. A clean is £100, deep cleaning runs £150 to £180, a filling is £149 to £349, a crown is £650 to £895, and root canal treatment starts from £399. The assessment itself is £20 with digital X-rays included, and the exact price of anything else comes to you in writing before it starts.

What to Take Away About a Black Tooth

If you've been putting this off because you're braced for the worst, here's the bit to walk away with: most black on a tooth turns out to be stain or tartar, so the fix is a clean and an afternoon of feeling rather pleased with yourself.

And where it is decay or a tooth that has died, it's still ordinary work with a known ending. One appointment with somebody who can see what it is beats weeks of wondering, every time. If it's been years since you last sat in a dental chair, going to the dentist after years is a kinder read than you'd expect.