Mais qu'est-ce que ça peut être? Voici une cause possible.
Black line stain on teeth is partially caused by dental plaque in the same manner as other topical stains on teeth are caused. However, the way the plaque was formed is the key to unlocking the mystery of black stains. All dental plaque is caused by bacteria. However, the type of bacteria that causes black stains is different than that which causes other stains. Black line stain is found near the gum line on both the front and back of the teeth and is more prevalent on the back teeth.
Chromogenic bacteria is the cause of the plaque on teeth that results in black line stain. This type of bacteria is known for causing calcification. In plaque caused by chromogenic bacteria the deposit of calcium along the gum line is the cause of children with black line stain to have a remarkably lower incidence of dental decay.
Further testing has shown an insoluable iron compound in the black line stain. It has now been proven the chromogenic bacteria and insoluable iron compound to be the cause of black line stain. It is thought the iron compound is formed due to the interaction of hydrogen sulfide produced by the chromogenic bacteria and iron in the saliva or gingival fluids.
A child with a high iron content in their body is at great risk for black line stain if they are not taught proper brushing and flossing techniques or the child does not follow through with proper brushing and flossing.
Extraits du texte suivant: http://www.helium.com/items/1297410-what-is-black-line-stain-on-teeth