In dentistry, a black triangle is a triangle-shaped space that appears between the teeth close to the gumline. These are spaces in-between the teeth and are the result of a gap between teeth- which is called a diastema when it is in the front teeth or receded or shriveled interdental gum tissue between any of the teeth. These spaces are created as a result of a retreat of the gum defined as gingival recession. If you look at healthy teeth closely, you will notice that there is a small amount of pink gum tissue that peaks up between your teeth. This is called the papilla and is what prevents these black triangles in the space between the teeth. If your gums are not kept healthy, the papillae will recede and can leave the black triangles behind.
Depending on the shape of your teeth, these triangles can be non-existent or can be large, unsightly, and bad for your overall oral health. This type of gingival recession is commonly a symptom of periodontitis, or advanced gum disease and is the main cause of the appearance of the black triangles.
Ironically, another reason for the appearance of black triangles is the treatment of periodontitis. Since periodontitis is an inflammatory disease, the gum swelling due to inflammation often covers spaces that would otherwise be uncovered. This means that following treatment of periodontal disease when the gingiva, as it heals, loses inflammation, deflates, and black triangles can appear. Beyond the aesthetic aspect which can be unpleasant, the flattening of the interdental papilla favors the retention of food residues and bacterial plaque and increases the risk of developing caries. For this reason, it is essential to follow the home hygiene instructions given by the hygienist and undergo re-mineralization therapies.
Additionally, the papillae will recede physiologically with age or in some some cases, the dark triangles are the result of an orthodontic treatment in which the front teeth were misaligned before the treatment.
The bottom line is that these black triangles are generally permanently there once they appear and will not just go away on their own.
What happens if you don’t fix the black triangles?
Unfortunately, the black triangles are not just a cosmetic problem, though this might be what makes you seek care in the first place! The problem with the black triangles is that, once they are there, not only do they not go away, but they also contribute to the quickening of the deterioration of your gums and the health of your teeth. Because the spaces are larger close to the gumline and in-between your teeth, they allow food that you eat to sit longer in those spaces if you do not brush your teeth right away after meals. When the food particles stay in-between your teeth, it gives the bacteria in your mouth opportunity and fuel; it allows for them to quickly harm your gums and teeth, accelerating degeneration. This will manifest in more cavities, tooth decay, further gum recession and could result in the loss of your teeth. See a dentist right away if you notice these black triangles- they won’t fix themselves and require professional intervention.