What to Know About Black Triangles

Medically Reviewed by Robert Brennan on April 25, 2023
3 min read

‌Black triangles between your teeth are also known as “open gingival embrasures.” These gaps are the result of your gum tissue not completely filling the space between your teeth. Some gaps can be normal. New or widening gaps may be a sign of dental problems. 

Here’s what you need to know.

There are several reasons you might develop “black triangles,” or gaps between your teeth along your gumline.

Tooth shape. Teeth come in different shapes and sizes. Rectangular teeth are equally wide at the top and bottom. Your incisors are the teeth at the front of your mouth. You may develop black gaps between your teeth if your incisors are narrower at the gum line than they are at the biting surface.

Receding gums. Conditions like gum disease can cause your gums to recede, or become thinner. Your gums stop filling up the natural spaces between your teeth and leave empty areas that look like black triangles.

Aggressive dental hygiene. Yes, you can brush your teeth too hard. You can hurt the tissue between your teeth if you regularly scrub your gums or floss too hard. This leads to gaps between your teeth just like gum disease.

Orthodontic treatment. Braces and other orthodontic treatments are meant to move your teeth to a safer or better-looking location. But these shifts can leave gaps between your teeth that may need further treatment.

Bone loss. Your gums will also start to recede if the bone underneath them starts to disappear. Bone loss can be caused by problems like osteoporosis and severe gum disease. Talk to your dentist if you think your black triangles might be caused by bone loss.

Black triangles are more likely to be a symptom of a health problem than the cause of one. You may notice gaps forming between your teeth that weren’t there before if you have gum disease or bone loss. Talk to your dentist if you notice new gaps developing. They can help you figure out the cause of your new gaps and treat their underlying health conditions.

The options for treating black triangles between your teeth depend on what’s causing them. The most common treatments include:

Brushing and flossing more carefully. You might be able to fix your black gaps just by being a little more careful if you’ve been overdoing it with your dental hygiene. Follow the American Dental Association’s guidelines for brushing and flossing without hurting your gums.

Treating gum disease. Your dentist can help you treat your gingivitis or gum disease. Your healing gums may refill the gaps they left when they receded and fix your black triangles.

Using an orthodontic treatment. You may be able to use braces to bring your teeth closer together and fill any gaps caused by the position of your teeth.

Applying dental resin or veneers. You can have dental resin or veneers applied to fill in the gaps if your teeth aren’t rectangular. Dental resin fills the gap between your teeth. Veneers cover the entire front of each tooth. Both change the shape and appearance of your smile.

Grafting tissue. Your dentist or orthodontist may recommend surgery if you have significant dental and gum problems. This method involves grafting additional tissue to the gums around your teeth. It may also involve bone grafts if you have substantial bone loss.

Want to avoid developing black triangles in the first place? Have you treated a past case and want to prevent them from returning? You have options. Most of the causes of black triangles are avoidable through simple changes to your dental routine.

Floss gently.Flossing too hard can hurt your gums instead of helping them. Floss carefully and avoid putting pressure on your gums so they don’t get irritated and start to recede.

Avoid using firm-bristle toothbrushes. You may end up brushing small parts of your gums just because of the shape of your teeth. Using a soft-bristle toothbrush puts less stress on your gums than a hard bristle alternative. Keeping your gums healthy can prevent a receding gumline and black triangles.

Avoid risk factors for gum disease. Common risk factors for gum disease include smoking and poor dental hygiene. You can avoid potentially unsightly black gaps between your teeth by keeping your gums healthy.