A black tooth is not always an emergency, but it can be one depending on what’s causing it and what other symptoms you have. A tooth that turns black gradually from coffee, tobacco, or tartar buildup is a cosmetic issue worth addressing at a routine appointment. But a tooth that darkens suddenly, or one accompanied by pain, swelling, fever, or pus, signals something more serious that needs prompt attention.
When a Black Tooth Is an Emergency
The color alone isn’t what makes it urgent. What matters is what’s happening underneath and around the tooth. Several warning signs turn a black tooth from a “call your dentist this week” situation into a “call your dentist today” situation:
- Sudden darkening: A tooth that turns black or dark grey over hours or days, especially after an injury, suggests internal bleeding or rapid decay.
- Throbbing or persistent pain: Pain that won’t let up, particularly when biting or chewing, points to nerve damage or active infection inside the tooth.
- Swelling in the gums or face: Puffy gums around the tooth or swelling that spreads into the cheek or jaw indicates an advancing infection that may need antibiotics quickly.
- Pus, foul taste, or fever: These are classic signs of a dental abscess. An abscess is a pocket of infection that can spread to surrounding tissues and, in rare but serious cases, into the bloodstream.
If you have a black tooth with none of these symptoms, you still need a dental evaluation, but you likely have days or weeks rather than hours to schedule it.
What Makes a Tooth Turn Black
There are two broad categories: staining from the outside and damage from the inside. Telling them apart at home isn’t always easy, but a few clues help.
External Staining
Dark deposits on the surface of a tooth come from things like coffee, tea, red wine, tobacco, or tartar buildup. These stains tend to affect multiple teeth rather than a single one, and they may lighten after brushing or a professional cleaning. Surface staining doesn’t cause pain or sensitivity.
Internal Damage
When a single tooth turns noticeably darker than its neighbors, the problem is usually inside the tooth. The most common internal cause is pulp necrosis, which means the living tissue inside the tooth has died. When the pulp dies, blood cells break down and release pigments that seep into the tiny tubes running through the tooth’s inner layer. The longer those pigments sit, the darker the tooth gets.
Pulp death happens for two main reasons: deep decay that reaches the nerve, or trauma (a hit to the face, a sports injury, even aggressive dental work). After trauma, the timeline varies widely. A mild injury can kill the pulp within three months, while more severe injuries like a tooth that gets pushed sideways or driven into the jawbone may not show discoloration for up to two years. In a large study of traumatic dental injuries, pulp necrosis was the most common complication, occurring in about 34% of injured teeth.
A single dark spot on a tooth, especially one that’s sticky to the touch or sits in a visible pit or groove, is more likely a cavity. Cavities tend to grow steadily over time rather than appearing and disappearing. They also cause sensitivity to hot and cold that stains don’t.
Why You Shouldn’t Ignore It
A black tooth caused by internal damage doesn’t heal on its own. If the pulp has died, the hollow chamber inside the tooth becomes a breeding ground for bacteria. Without treatment, that infection can form an abscess at the root tip, and from there it can spread into the jaw, the neck, or even the chest cavity.
The consequences of letting a dental infection run unchecked can be severe. Deep neck infections originating from teeth carry risks of airway obstruction, blood clots in the jugular vein, and sepsis. A case report published in The American Journal of Case Reports documented a patient whose untreated dental abscesses led to sepsis, heart failure, and death. These outcomes are rare, but they underscore why an infected black tooth isn’t something to put off indefinitely.
How a Black Tooth Is Treated
Treatment depends entirely on whether the tooth is still alive and how much structure remains.
If the pulp is dead or infected, a root canal is the standard treatment. The dentist removes the dead tissue from inside the tooth, cleans and disinfects the internal chamber, and seals it. This eliminates the source of infection and saves the tooth’s outer structure. If enough of the tooth has been destroyed by decay, a crown may be placed over it afterward for strength.
If the tooth is too far gone to save, extraction is the remaining option. Your dentist can then discuss replacement with an implant, bridge, or other restoration.
For teeth that are structurally sound after a root canal but still discolored, internal bleaching can restore a more natural color. This procedure places a whitening agent directly inside the tooth chamber through the same access point used during the root canal. The agent stays sealed inside the tooth for several days, and the process typically takes two to three appointments over a few weeks to match the surrounding teeth. It’s a conservative approach that avoids the need for a crown or veneer purely for cosmetic reasons, and the results tend to last longer than external whitening for this type of discoloration.
What to Do Right Now
Start by looking at the tooth in good light. Ask yourself a few questions: Is the discoloration on one tooth or several? Is it on the surface, or does the whole tooth look dark from within? Do you have any pain, sensitivity to temperature, swelling, or a bad taste? Can you remember any injury to that area, even months ago?
If the tooth is painless, not swollen, and the discoloration seems like surface staining across multiple teeth, schedule a routine cleaning and exam. Your dentist can confirm whether it’s just staining or something deeper.
If a single tooth has turned dark, especially with any pain or swelling, call for an appointment as soon as possible. Most dental offices can fit in urgent cases within a day or two. An initial exam with X-rays at an urgent dental visit typically costs around $120, though this varies by location and provider. The X-ray will reveal whether the pulp is dead, whether there’s an abscess forming at the root, and how much of the tooth can be saved.
If you have facial swelling that’s spreading, difficulty swallowing or breathing, or a fever along with a black tooth, that’s a true emergency. Head to an emergency room if you can’t reach a dentist immediately.