Why did a black piece chip off the back of my tooth?

In most cases, a black piece that chipped off the back of your tooth is hardened tartar — not the tooth itself. Losing tartar does not damage the tooth, so while the moment can feel alarming, the situation is usually less serious than it looks. What came off is almost certainly one of three things: hardened tartar, a fragment of an old filling or a small chip from a tooth weakened by decay. Knowing the difference between these three tells you how urgently you need to act.

What you'll learn in this article:

• Hardened tartar is the most common culprit — and its loss does not harm the tooth itself

• Old silver fillings darken to near-black over time and can fracture away, leaving a rough crater

• Unlike tartar, a chip from a decayed tooth has a sharp or rough edge and may be sensitive to cold or sweets

• The texture and color of the piece — plus how the spot feels to your tongue — can help identify what broke off

• A lack of discomfort does not mean there isn’t a more serious problem; many filling fractures and chips cause zero discomfort

The piece that broke off is only part of the story. Even if it turns out to be harmless tartar, it's still worth having the area checked. Schedule a visit with an Aspen Dental provider to find out whether you simply need a cleaning or if the tooth or an old filling needs treatment.

What the black piece most likely is

The back of the tooth matters here. The inside surfaces of your lower front teeth and the backs of your molars are where tartar builds up fastest. That makes tartar the most likely culprit — but there are two other possibilities worth knowing.

Hardened tartar — the most common reason

Tartar, also called calculus, is plaque that has hardened on the tooth over time. Without consistent brushing and flossing, plaque can harden into tartar in as little as 24 to 72 hours — and once it forms, only a professional cleaning can remove it.¹

This buildup can turn dark brown or black from coffee, tea, tobacco or other stains. Because it forms like a hard crust on the tooth, it can easily crack and break off while you are chewing or brushing. The broken piece is usually hard with one smooth side that was pressed against the tooth. It may also feel chalky or gritty when handled.

Losing a piece of tartar does not damage the tooth itself. However, any tartar left behind can irritate your gums and increase your risk of gum disease, so it should be professionally removed at your next dental cleaning.

A fragment of an old filling

Silver amalgam fillings — the metallic ones common in older dental work — oxidize and darken to near-black as they age. If you have an older filling on a back tooth, a piece of it can break away under biting pressure. The fragment will feel hard and metallic. You may also notice a crater or rough spot where the filling used to sit.

Unlike tartar, a missing filling fragment does need attention. The exposed area collects bacteria easily and can develop new decay if left unrepaired.

A chip from a tooth weakened by decay

Sometimes a tooth that has been softened by decay loses a piece of its outer layer. According to the CDC, about 1 in 4 adults in the United States has untreated tooth decay — so this is not uncommon.² When the enamel breaks, the darkened, softened area underneath becomes visible. You may notice a sharp or jagged edge on the tooth, or sensitivity to cold, heat or sweets. This is the scenario that warrants the most prompt attention.

What to do right after it happens

These steps are the same regardless of what broke off:

• Rinse your mouth gently with warm water to clear any loose debris

• Save the piece if you can — looking at it later helps determine what it is

• Run your tongue carefully over the spot to feel for a sharp edge, a crater or any change in the tooth surface

• Avoid pressing on the area or chewing on that side until it has been looked at

If a sharp edge is catching your tongue or cheek, a small piece of dental wax — available at most pharmacies — can cover the spot temporarily until your appointment.

How to tell what came off

Now that you know the three most likely possibilities, here is how to figure out which one you are dealing with. Examine the piece if you still have it:

• Smooth on one side, rough or gritty on the other — yellowish to black: Almost certainly tartar.

• Crumble test: Press the piece firmly between your fingers. If it crumbles or breaks apart like chalk, it is tartar. Actual tooth enamel and filling material will not crumble — they hold their shape under pressure.

• Hard, metallic and dark gray or black: Likely a piece of an old amalgam filling.

• White, off-white or translucent — looks like tooth material: Possibly actual enamel or dentin.

Now run your tongue over the spot where the piece came from. If the tooth feels smooth and intact, it points toward tartar or a filling fragment. If you feel a jagged edge, a crater or noticeable sensitivity, it is more likely the tooth structure itself.

Symptoms that need prompt attention

Most of the time, a dark chip from the back of a tooth is not a dental emergency. These symptoms, however, signal something that should not wait:

• A sharp or jagged edge that catches your tongue or cheek

• Sensitivity to cold or heat that lingers after the temperature is gone

• Throbbing or aching in the tooth or surrounding jaw

• Swelling or tenderness in the gum around the tooth

• A visible dark crater or hole on the tooth surface

Any one of these points to a problem with the tooth itself. Getting seen promptly by a dental professional prevents the issue from progressing to something that requires more involved treatment.

When to see your dental provider

Regardless of what broke off, your dental provider can examine the area, confirm the cause and recommend next steps.

• If it was tartar: A professional cleaning removes remaining buildup and protects your gum tissue

• If it was a filling fragment: The filling can be repaired or replaced to seal and protect the tooth

• If it was tooth structure: Options range from bonding or a filling to a crown, depending on the size of the chip and whether decay is involved

Visit an Aspen Dental office near you — even if the area feels completely normal. A small problem caught early is almost always easier and less costly to treat than one that is left alone.

Why did a black piece chip off the back of my tooth FAQs

Can very dark or black tartar be a sign of gum disease?

Yes. Tartar below the gumline is often darker than tartar on the surface of the tooth and is commonly linked to gum disease.

If the piece that broke off was very dark and your gums are swollen, tender or bleed when you brush or floss, let your dental provider know. A professional cleaning and gum health exam can determine whether gum disease is present.

Is it safe to keep brushing over the spot where the piece came off?

Yes, but brush gently. Use a soft-bristled toothbrush and avoid pressing firmly on the area. If brushing causes sensitivity or you feel a sharp edge, that is worth mentioning to your dental provider at your next visit.

My tooth feels completely normal — do I still need to be seen?

Many filling breaks and enamel chips cause no sensitivity at all, especially early on. The nerve inside the tooth may not be affected yet. A lack of discomfort does not mean there isn’t a more serious problem. If you noticed a rough spot or a visible dark area, an evaluation is still a good idea.

Could grinding my teeth cause this?

Yes. Grinding — also called bruxism — puts repeated stress on teeth that can gradually fracture enamel and weaken older fillings. If you tend to grind at night or clench during the day, your Aspen Dental provider can assess the wear on your teeth and discuss options to protect them going forward.

What if I swallowed the piece?

Don't worry. Swallowing a small piece of tartar, tooth or filling material is usually not harmful. It will typically pass through your digestive system without causing problems.

The more important question is what the tooth looks and feels like now. If you notice a rough edge, sensitivity or a hole where the piece came from, have the area checked by your dental provider.

Sources

¹Cleveland Clinic. Tartar on Teeth (Dental Calculus): Causes & Removal. https://my.clevelandclinic.org/health/diseases/25102-tartar

²Centers for Disease Control and Prevention. Oral Health: Fast Facts and Data. https://www.cdc.gov/oral-health/data-research/facts-stats/index.html