A diastema is a gap or space between two teeth. While these gaps can appear anywhere in the mouth, the most common type is a midline diastema, which is the visible space between the two upper front teeth. About 6% of adults have a midline diastema, and it’s slightly more common in women (7.4%) than men (4.4%). Some people consider their gap a distinctive feature and leave it alone. Others want it closed for cosmetic or health reasons. Either way, understanding what causes it helps you decide what, if anything, to do about it.
What Causes a Diastema
Gaps between teeth develop for a range of reasons, from genetics to everyday habits. The most straightforward cause is a mismatch between tooth size and jaw size. If your teeth are small relative to your jawbone, there’s simply more room than the teeth can fill, and spaces appear. This type of spacing tends to run in families and often shows up as multiple small gaps rather than one large one.
Another common culprit is the frenum, the small fold of tissue that connects your upper lip to your gums. When this tissue is unusually thick or attaches too low on the gum line, it can physically wedge between the two front teeth and prevent them from coming together. In these cases, the gap won’t close on its own without addressing the tissue itself.
Habits play a role too. Tongue thrusting, where the tongue pushes forward against the front teeth during swallowing, exerts repeated force that gradually pushes teeth apart. Thumb sucking in childhood works the same way. Both are recognized as major factors in developing misaligned teeth, and the longer the habit continues, the more pronounced the gap becomes.
Gum disease is a significant acquired cause, especially in adults who didn’t have a gap earlier in life. When periodontal bacteria trigger chronic inflammation, the bone that anchors your teeth gradually breaks down. As that bone is destroyed, connective tissue fills the empty space, making it difficult for new bone to form. Teeth lose their structural support, shift out of position, and gaps open up. If a diastema appears in adulthood where none existed before, gum disease is one of the first things to investigate.
Gaps in Children Are Often Normal
If your child has a gap between their front teeth, it’s probably not a problem. During the “ugly duckling stage” of dental development, the upper front adult teeth erupt in a flared position with noticeable spacing between them. This looks alarming but is completely transitional. Once the upper canine teeth (the pointed ones next to the front teeth) come in, they typically push the front teeth together, and the gap closes on its own. Orthodontic treatment at this stage is rarely necessary unless other alignment issues are present.
Does a Diastema Affect Oral Health?
A small gap between teeth isn’t inherently dangerous, but it does create a space where food gets trapped more easily. When food is repeatedly wedged into the same spot during chewing, it irritates the surrounding gum tissue and leads to plaque buildup. Over time, that plaque accumulation increases the risk of cavities on the sides of the teeth facing the gap and can trigger gum inflammation, pocket formation, and even bone loss around those teeth.
The practical concern is access. Gaps that are too wide or oddly shaped can be harder to keep clean with regular brushing alone. Interdental brushes or floss threaders help, but the key point is that a diastema requires a bit more attention to hygiene in that specific area. Left unchecked, the food impaction cycle can accelerate the very bone loss that makes gaps worse.
Treatment Options and What They Cost
Treatment depends on what’s causing the gap and how large it is. There are three main approaches, each with different tradeoffs in cost, durability, and time.
Dental Bonding
Bonding is the quickest and least expensive option. Your dentist applies tooth-colored resin to the sides of the teeth bordering the gap, effectively widening them to close the space. It’s done in a single visit and costs roughly $100 to $400 per tooth. The downside is durability: bonding material can chip or stain over the years and may need to be redone.
Porcelain Veneers
Veneers are thin shells bonded to the front surface of your teeth. They close the gap by changing the visible shape and width of the teeth. Porcelain veneers cost between $1,000 and $2,500 per tooth, while composite veneers fall in the $250 to $1,500 range. Porcelain is more durable and stain-resistant than bonding, making it a longer-lasting cosmetic solution. Veneers and bonding work best when the gap is caused by a tooth size discrepancy rather than teeth being in the wrong position.
Orthodontic Treatment
Braces or clear aligners physically move the teeth together over time. This is the better choice for larger gaps or when teeth are also misaligned in other ways. The results tend to be the most long-lasting because the teeth themselves are repositioned rather than covered. Treatment timelines vary from several months to a couple of years depending on the complexity. A retainer afterward is essential to keep teeth from drifting back.
When a Frenectomy Is Needed
If a thick or low-attaching frenum is the reason for a midline gap, closing the space with braces or bonding alone may not hold. The tissue will continue pushing the teeth apart. In these cases, a frenectomy removes or repositions the frenum. It’s a minor surgical procedure, and recovery is straightforward: dressings and sutures typically come out about one week after the procedure. A frenectomy is usually done in combination with orthodontic treatment rather than as a standalone fix.
Treating Habit-Related Gaps
When tongue thrusting or thumb sucking is driving the gap, closing it without addressing the habit is a losing battle. The teeth will simply shift back. Treatment follows a three-step approach: identifying and removing the trigger, retraining the muscles involved, and sometimes using a mechanical appliance. A tongue crib, for example, is a small device placed behind the upper teeth that physically blocks the tongue from pushing forward during swallowing. It works as both a restraint and a reminder, gradually retraining the swallowing pattern. Once the habit is broken, orthodontic treatment can close the gap with a much lower chance of relapse.