Arianna Ritchey, RDH
BLACK LINE STAIN
During the regular prophylaxis cleaning for a recent patient, she inquired as to the black stain on her teeth. She had excellent brushing and flossing habits, saw us every six months for her professional cleanings, and has only one filling on her permanent teeth. This patient does not participate in any behaviours that normally result in staining; she does not drink coffee, tea, wine, and she does not use any tobacco products. She was also concerned, because this same type of stain is also present on her infant’s teeth, who is strictly breastfed. So, where was this stain coming from?!
It was explained to this patient that the stain she was experiencing was most likely a type of stain called “Black Line Stain,” or sometimes simply “Black Stain”. Black Line Stain is more common in women than men, and can occur in patients with excellent oral hygiene. It appears as a thin black line, which is firmly attached to the tooth surface, and most commonly near the gumline of the facial and lingual surfaces of a tooth. This type of stain is associated with a low incidence of cavities in children and adults, and is caused by a type of Gram-positive bacteria that produces a certain colour, or chroma, which makes it identifiable. It is possible that this patient’s child has the same type of Gram-positive chromogenic bacteria on his teeth, creating the same type of Black Line Stain. This is especially likely if the child has good oral hygiene and a low incidence of cavities.
This non-metallic type of stain is absorbed onto the tooth surface deposits, such as tartar, plaque, or even the acquired pellicle. The acquired pellicle is a thin film made up of proteins in our saliva, that forms almost instantly after a tooth is cleaned. Because this type of bacteria is able to attach to the acquired pellicle, this condition is not related to oral cleanliness or the presence of periodontal disease.
To prevent this stain from building up as quickly, patients can use a toothbrush to effectively clean the teeth twice a day, while using a toothpaste that helps to prevent staining. Powered toothbrushes can often clean the teeth most effectively without causing trauma to the gums. Once the stain has settled onto the teeth, the most effective way to remove this Black Line Stain is by a professional cleaning with a dental hygienist. The hygienist may professionally remove the stain with an ultrasonic scaler, coronal polishing using an abrasive prophy paste, or by using an air-jet polisher with an abrasive powder.
The only real downside to removing the Black Line Stain from the teeth, is that repeated stain removal using an abrasive paste or powder removes micro-millimeters of enamel from the tooth surface. The top layer of the teeth which is partially removed during polishing, is the most fluoride-rich part of the tooth, so if frequent polishing is utilized to remove Black Line Stain, it is advisable to have a professional fluoride treatment administered after the polishing to replenish the depleted fluoride from the teeth. Fluoride is available in a few different forms, the most effective of which are a fluoride varnish or a fluoride foam.
There are some other types of dark stain that are caused by other sources, including dietary components, beverages, tobacco, mouthrinses and other medicaments. These types of stain have a different source than Black Line Stain, but are removed in a very similar fashion. If you have any questions or further concerns about staining on your teeth, feel free to ask your dental hygienist!
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