What are black triangles?

A black triangle, more formally called an open gingival embrasure, is the small triangular space that can appear between two teeth just above the gum line. When healthy gum tissue fills this space, the teeth look connected and complete. When that tissue doesn't fully fill the gap, a dark, triangular space becomes visible.

They're most noticeable between the upper front teeth, which is exactly why they tend to bother people cosmetically. Because that area is the focal point of your smile, even a small gap can feel very obvious to the person looking in the mirror.

Why do they appear after braces or Clear Aligners?

It can feel unfair to complete orthodontic treatment only to be left with a new concern. The important thing to understand is that orthodontics doesn't usually create the underlying conditions for black triangles; it reveals or reshapes them as your teeth move into their new positions.

There are several common reasons they appear after treatment:

Tooth shape

Some teeth are naturally more triangular than rectangular, narrower at the gum line and wider towards the biting edge. When teeth like this are aligned, the contact point where they touch sits higher up, leaving a wider space beneath it that gum tissue may not fully fill.

Gum recession and tissue changes

The gum tissue that sits between teeth, called the papilla, can recede or thin over time. This is more common with age, and can also follow the movement of teeth during orthodontic treatment. If the papilla doesn't sit high enough to fill the space, a triangle appears.

Previous gum disease or bone loss

If there has been gum disease or a loss of bone height between the teeth in the past, the supporting tissue may no longer be able to fill the embrasure fully. As teeth are straightened, this can become more visible.

Crowding that masked the gaps

Before treatment, crowded or overlapping teeth can hide these spaces entirely. Once the teeth are aligned and properly spaced, the embrasures become visible for the first time, even though the underlying tissue situation hasn't fundamentally changed.

Are black triangles a health problem?

In most cases, black triangles are a cosmetic concern rather than a threat to your dental health. However, they can trap food and plaque more easily, which makes thorough cleaning important. Using interdental brushes or floss to keep these spaces clean helps protect the surrounding gums and teeth.

If a black triangle has appeared because of ongoing gum disease, then the underlying condition does need attention, and that's something worth having assessed rather than ignored.

What can be done about black triangles?

The right treatment depends on the size of the triangle, the health of your gums and what you're hoping to achieve. Options range from simple, non-invasive approaches to more involved treatments, and not every option suits every case. A proper assessment is the only way to know which is appropriate for you.

Composite bonding

One of the most common and least invasive common first step solutions, composite bonding involves adding tooth-coloured resin to the sides of the teeth to gently reshape them and close the gap. It usually requires little to no removal of a natural tooth, can often be completed in a single visit, and delivers an immediate cosmetic improvement.

Interproximal reduction and reshaping

In some cases, carefully reshaping the contact points between teeth, sometimes combined with a short period of orthodontic movement, can bring the teeth closer together and reduce the space. This is more suitable for certain tooth shapes and smaller triangles.

Veneers

For those looking to change the overall appearance of their teeth as well as close black triangles, porcelain veneers can reshape the teeth and eliminate the gaps. This is a more significant cosmetic treatment and is usually considered when there are broader aesthetic goals. Have a look here at our Veneers treatment, best results long term and recommended if we've tried the bonding and IPR already.

Gum treatments

Where the gum tissue or its health is the main factor, treatments aimed at supporting or regenerating the papilla may be discussed. These are more specialised and their suitability depends heavily on the individual case.

The most important first step

Because black triangles have several possible causes, there's no single fix that works for everyone. The best starting point is an assessment where we can look at your tooth shape, gum health and the size of the spaces, and talk through what's realistic and appropriate for your smile.

If black triangles have appeared after your braces or Clear Aligners and they're affecting how you feel about your smile, we'd be glad to help. Book a consultation with our team at Siha Dental and we'll explain your options clearly, with no pressure, so you can decide what's right for you.

Frequently asked questions

Are black triangles after braces permanent?

Not necessarily. While they won't usually close on their own, several treatments can reduce or eliminate them, from composite bonding to reshaping and, in some cases, gum treatments. The right option depends on your individual situation.

Did my braces or Clear Aligners cause the black triangles?

Orthodontic treatment usually reveals or reshapes existing conditions rather than creating them. Factors such as tooth shape, gum position and previous bone loss are typically the underlying cause, and become more visible once the teeth are aligned.

Can black triangles be closed without veneers?

Yes. Composite bonding is a common, minimally invasive way to close black triangles without veneers, and in some cases reshaping the teeth with a short period of orthodontic movement can help. The best approach depends on the size of the gap and the shape of your teeth.

Are black triangles bad for my teeth?

They're usually a cosmetic concern rather than a health problem, but they can trap food and plaque, so keeping them clean with interdental brushes or floss is important. If they've appeared because of gum disease, the underlying condition should be assessed.

How much does it cost to fix black triangles?

Black triangle closure with composite bonding at Siha Dental starts from £250 per surface. As a guide one large gap requires composite bonding on two teeth, one surface each. We'll always talk through the options and costs at your consultation so you can make an informed decision and we aim for the most natural results, which is why we get a lot of patients seeking this result.