A tooth turning grey often signals an underlying issue within its structure. This discoloration is more than a cosmetic problem; it frequently indicates something has affected the tooth’s internal health. Understanding these reasons helps in recognizing when professional dental care is needed.
Internal Bleeding and Pulp Damage
Internal bleeding within the pulp chamber is a primary reason a tooth can turn grey, often caused by dental trauma. An impact to the mouth, such as from a fall or a sports injury, can rupture tiny blood vessels inside the tooth’s pulp. The release of blood products, particularly hemoglobin, then seeps into the microscopic tubules of the dentin, the layer beneath the enamel.
As these blood products break down, they release iron compounds that react with hydrogen sulfide, forming iron sulfides. These compounds are dark in color, causing the tooth to gradually develop a grey or even blackish hue. This discoloration may not appear immediately after the injury but can manifest weeks or even months later, as the breakdown process unfolds.
Pulp necrosis, the death of the tooth’s nerve and other pulp tissue, is another cause. This condition can result from severe trauma, deep decay, or infection. When pulp tissue dies, it decomposes, releasing by-products that penetrate the dentinal tubules and stain the tooth a greyish-brown. The longer the pulp remains necrotic, the more intense the discoloration becomes.
Dental Materials and Procedures
Certain dental materials and past procedures can also contribute to a tooth turning grey. Older amalgam fillings, often called “silver fillings,” are a common culprit. Over time, these fillings, which contain a mixture of metals including silver, tin, copper, and mercury, can corrode.
This corrosion can lead to the leaching of metallic ions, such as silver sulfide, into the surrounding dentin. These ions then stain the tooth structure, resulting in a grey or bluish-grey tint that can be visible through the tooth’s enamel. This internal staining is distinct from surface stains and is not easily removed by regular cleaning.
A tooth that has undergone root canal treatment might also develop greyish discoloration. This can occur if residual pulp tissue fragments are left within the pulp chamber or pulp horns. These remnants can decompose and cause staining. Additionally, certain root canal filling materials or medications used during the procedure can contribute to tooth discoloration over time.
When to Consult a Dentist
If a tooth begins to turn grey, consult a dentist promptly. This discoloration often indicates an underlying problem, such as nerve damage or infection, which will not resolve on its own. Delaying professional evaluation can allow the condition to worsen, potentially leading to more extensive issues.
Seeking dental attention is important if the grey discoloration is accompanied by other symptoms, such as pain, swelling, or increased sensitivity to temperature. If the color change follows a recent injury or trauma, a timely dental visit can help diagnose the damage and prevent complications, such as infection spread to surrounding tissues.
Restoring Tooth Color
Once the underlying cause of the grey tooth has been addressed and its health evaluated, several treatment options can restore its natural color. For non-vital teeth (where the pulp has died), internal bleaching is a common method. This involves placing an oxidizing agent, such as hydrogen peroxide or sodium perborate, directly into the pulp chamber to lighten the tooth from the inside.
Porcelain veneers are another option for restoring tooth color, especially for persistent discoloration. These thin, custom-made porcelain shells bond to the tooth’s front surface, concealing discoloration and providing a natural, brighter appearance. Veneers are effective for intrinsic stains that do not respond to bleaching.
Dental crowns offer another solution, especially for teeth with severe discoloration or significant structural damage. A crown is a tooth-shaped cap that completely covers the visible portion of the tooth, restoring its original shape, size, and strength, while providing a uniform, natural shade. The choice of treatment depends on the cause and extent of discoloration, plus the tooth’s overall health and structural integrity.