Black lines on crowns occur from older dental techniques that have used a metal or cheaper foundation material for the creation of the crown. Black lines around crowns and veneers should never occur in modern dentist practices as porcelain is mainly used for dental crowns and veneers.
In most cases, a black line forms because the metal from the crown is showing through. Since older dental crowns are typically made of porcelain fused to metal, the metal will eventually become exposed as the gumline moves and recedes over time.
A gingival retraction cord is typically the most effective method for moving and retracting gum tissue in order to provide a clear working view of the tooth. A clear working view of the tooth is crucial so that the dentist can ensure that no mistakes are made.
The Meaning of the Black Line
In most cases, a black line around a dental crown is a direct result of the crown's composition. Many crowns are made of porcelain fused to metal (PFM). Such crowns have a tough metal shell on the inside, which is surrounded by porcelain.
Black lines caused by tartar build up
Plaque forms naturally on teeth, particularly near the gum lines. If not removed through brushing and flossing, this plaque will calcify and harden into tartar, also known as calculus. Tartar can only be removed by a dentist.
As the porcelain thins near the gum line and the gum line recedes over time, exposing portions of the metal base, causing the dark lines where the metal appears.
Periodontal disease, aggressive brushing, teeth grinding or shifting teeth can all lead to gum recession. In this case, a black line may actually be part of the natural tooth structure if you had a root canal or traumatic injury before receiving the crown.
Black lines on teeth may appear to be cavities, but they aren't. These black lines on teeth are simply a natural kind of tartar, commonly known as dental calculus. Tartar is formed when mouth plaque absorbs minerals from saliva and gets petrified.
A dental crown is a tooth-shaped cap that restores a decayed, broken, weak or worn-down tooth. Dentists also use crowns to cover dental implants and root canal-treated teeth. Made from a variety of materials, including metal, resin and porcelain, crowns last between five and 15 years with proper care.
Brown and grey spot formations are a distinct visual indicator of a potential infection or tooth decay under a dental crown. Spots can be visible on the white portion of a veneer, almost appearing like mould.
Inflammation or swelling of the gums around the crown area. Pain when chewing or biting down. Tooth sensitivity to temperatures (hot or cold) or sugary foods and drinks. Pain or tenderness in the areas surrounding the crown.
It is not uncommon for tooth decay to develop beneath older crowns due to a breakdown in the bond or sealant after years of biting or chewing food. Dr. Knight will remove the existing crown to clean out the current tooth decay, replacing it with a new one once the tooth is fully healed and healthy again.
While tooth crowns are designed to protect a damaged tooth, they can still cause pain and become infected, just like normal teeth. However, while tooth crown pain is uncomfortable, it is usually simple to alleviate, either through medication or follow-up treatment from your dentist.
The gray line around the edge of your old crowns is most probably caused by the metal edge of the crown showing through the gum.
But, what many do not realize is that sometimes it is possible to get decay under a dental crown. This can happen if all of the infected tissue was not taken out of the root, or if the crown was not placed correctly, allowing bacteria to cause decay. If decay gets under a crown, it might need to be replaced.
If you notice that a crown looks misshapen or has visible dings, dents, or chips, you should certainly visit your dentist before the damage causes the crown to fail altogether.
It's possible that a crown or an implant might need to be replaced at some point, but both offer a good value for the money. Back teeth typically see more wear and tear from chewing, so they will usually be the first to wear out. Crowns typically last from 5 to 15 years. Implants can last upwards of 25 years.
Some crowns are able to last a lifetime whereas others may crack and need to be replaced. On average, a crown can last between 10 and 30 years when well cared for.
Dental crowns are typically the best option if your tooth is very damaged, has a large filling, or has undergone a root canal, since the tooth enamel is more compromised and will need better protection. Porcelain veneers, on the other hand, are best for purely cosmetic purposes.
Many patients wonder if the tooth can still decay after treatment. Yes, the treated tooth can still decay. Even a root canal followed by a crown will not prevent the tooth from decaying.
Over time the cement wears down, leaving space for material like bacteria and food to enter. This bacteria can lead to a bad smell. Space for bacteria to flourish can also occur if a crown becomes loose for any reason.
The biggest sign of veneer discoloration is a black line that appears near the gum line. This happens when veneers do not fit well and there is a gap between the gum line and the veneer. The dirt and bacteria tend to accumulate in the space and form a black line.
Darkening natural teeth – Porcelain veneers are translucent, so if your teeth are getting darker behind the veneers, the color will show through. If your veneers are leaking and bacteria are seeping between them and your teeth, your teeth will look darker.
Gum recession
This is because as your gums recede, it creates a tiny gap in between the veneer and your gum. This space can be hard to reach when brushing your teeth, leading to a build-up of bacteria which causes tooth decay and, ultimately, discolouration.