A tooth appearing black inside is alarming. It signals an underlying issue within the tooth structure, requiring professional dental attention.
Common Causes of Internal Tooth Darkening
One frequent reason for a tooth to darken internally is advanced dental caries (cavities). As bacteria erode the enamel and dentin, the tooth structure can change color and appear black. If left untreated, this decay can spread deeper into the tooth, reaching the pulp, causing further discoloration.
Another significant cause is trauma or injury to the tooth. A blow can damage the delicate pulp, containing nerves and blood vessels. This can lead to internal bleeding, similar to a bruise on the skin, causing it to darken over time, turning gray or black. This discoloration can occur immediately or develop gradually over weeks or months as blood breaks down.
Existing dental work, particularly old amalgam (silver) fillings, can also darken teeth internally. Over time, these metallic fillings can corrode, releasing ions that leach into the tooth structure. This process stains the tooth from the inside, giving it a gray or bluish-gray appearance which can appear black. This staining is usually cosmetic and doesn’t indicate a new health issue.
Certain medications, when taken during tooth development, can cause intrinsic staining. Tetracycline, an antibiotic, is a notable example; it binds to calcium ions during tooth mineralization, incorporating into the tooth structure. This results in permanent discoloration that can range from yellow to gray or brown.
Recognizing Accompanying Signs and Symptoms
Other symptoms can accompany internal tooth darkening. Pain or sensitivity is a common sign, manifesting as a sharp, throbbing ache or heightened sensitivity to hot and cold. This discomfort often suggests inflammation of the pulp or an infection.
Swelling around the gum line or face, or a pimple-like bump on the gums (a fistula), can indicate a spreading infection or an abscess. These signs suggest bacteria have spread beyond the tooth, potentially affecting surrounding tissues. A persistent bad taste in the mouth or chronic bad breath may also be present due to infection.
A tooth can appear black inside without pain or immediate symptoms. This can occur in cases of long-standing decay not yet reaching the nerve, or a dead tooth where the nerve has died, eliminating pain. Regular dental check-ups are important for identifying these asymptomatic issues.
When to Seek Professional Dental Care
Any internal tooth discoloration warrants a prompt visit to a dental professional, as the discoloration itself signals an internal issue requiring evaluation. Delaying a dental examination can allow underlying problems to worsen.
Seeking early diagnosis prevents further tooth damage, limits infection spread, and often leads to less complex, invasive treatments. A dentist can accurately determine the discoloration’s cause and recommend the most appropriate action.
During the dental examination, the dentist will conduct a visual inspection, probe the tooth, and take X-rays. These diagnostic tools assess the tooth’s internal structure, identify decay or damage, and evaluate the pulp and surrounding bone.
Addressing the Discoloration: Treatment Options
Treatment for an internally darkened tooth depends on the underlying cause. If the discoloration is due to dental decay, the affected portion of the tooth will be carefully removed. The tooth is then restored with a filling, such as composite resin.
For cases involving damage to the tooth’s pulp from deep decay or trauma, root canal therapy may be necessary. This procedure involves removing the infected or damaged pulp, cleaning, shaping, and sealing the root canals to prevent further infection. After a root canal, a crown might be recommended to protect the weakened tooth and restore its function and appearance.
In severe cases where the tooth is extensively damaged or infected beyond repair, extraction may be the only viable option. This prevents the infection from spreading.
For aesthetic concerns following a root canal, especially if the tooth remains discolored, internal bleaching can be an option. Unlike external whitening, internal bleaching involves placing a bleaching agent inside the tooth to lighten it from within. This procedure is typically performed after successful root canal therapy and can significantly improve the tooth’s color.
Preventing Future Tooth Discoloration
Maintaining excellent oral hygiene helps prevent internal tooth darkening caused by decay. This includes brushing teeth twice daily with fluoride toothpaste for two minutes, and flossing daily to remove plaque and food particles from between teeth and gumline. Consistent cleaning helps prevent the buildup of bacteria that leads to decay.
Dietary choices also play a role in preventing tooth decay. Limiting sugary and acidic foods and drinks reduces the risk of enamel erosion and cavity formation. Rinsing with water after consuming staining substances can also minimize discoloration.
Regular dental check-ups and professional cleanings are important for early detection and prevention. These routine visits allow dentists to identify and address problems like early decay or minor trauma before they lead to significant internal discoloration. Additionally, wearing a mouthguard during sports or other activities with dental injury risk can help protect teeth from trauma that causes internal darkening.