What Is a Diastema and Why Do Gaps Form?
A diastema is a gap or space between two teeth that measures 0.5 mm or wider. While gaps can occur anywhere in the mouth, the most visible and commonly treated gap is the midline diastema, the space between the two upper front teeth (central incisors).
Gaps between teeth are extremely common. Studies estimate that midline diastemas occur in roughly 20% of adults. In children, gaps between baby teeth are normal and often close naturally as the permanent teeth come in. However, if spaces remain after the permanent canine teeth have fully erupted (usually by age 13), they are unlikely to close on their own.
For some people, a small gap is a cosmetic feature they embrace. For others, gaps cause self-consciousness, affect speech, or allow food to pack between teeth and irritate the gums. Whether to close a gap is a personal decision, but effective treatments are available when you choose to address it.
What Causes Gaps Between Teeth
Understanding the cause of your gap helps the orthodontist plan the most effective and stable treatment approach.
Tooth Size Discrepancy
When the teeth are smaller relative to the size of the jawbone, there is more space than the teeth need. This tooth-size-to-jaw-size mismatch is largely genetic. It often results in generalized spacing throughout the arch, not just a single gap. The upper lateral incisors (the teeth next to the front teeth) are especially prone to being undersized, creating gaps on either side.
Missing Teeth
If a tooth never developed (congenitally missing) or was lost to decay or injury, the remaining teeth may drift apart over time, creating gaps. The most commonly missing teeth are the upper lateral incisors and the second premolars.
Labial Frenum
The labial frenum is the small band of tissue that connects the inside of the upper lip to the gum above the front teeth. If this tissue is unusually thick or attaches too low between the front teeth, it can physically prevent the teeth from coming together. In these cases, a minor procedure called a frenectomy may be recommended before or during orthodontic treatment.
Habits and Tongue Thrust
A tongue thrust swallowing pattern, where the tongue pushes forward against the front teeth during swallowing, can gradually push the teeth apart over time. Thumb sucking in childhood can also create or widen a gap between the front teeth. If the habit is not addressed, it can cause a gap to reopen even after orthodontic closure.
Gum Disease
Advanced periodontal disease (gum disease) destroys the bone that supports the teeth. As bone is lost, teeth can loosen and drift, creating new gaps. If gum disease is a contributing factor, it must be treated and stabilized before orthodontic gap closure can begin.
How Braces Close Gaps: What to Expect
Braces close gaps by applying controlled force that moves teeth toward each other through the archwire system.
Consultation and Treatment Planning
Your orthodontist will take X-rays, photos, and impressions or digital scans. They will measure the size of the gap, assess your bite, check for missing teeth or other contributing factors, and determine whether braces, aligners, or a combination approach is best.
If a frenum is contributing to the gap, the orthodontist may coordinate with a periodontist or oral surgeon for a frenectomy. If gum disease is present, periodontal treatment must be completed first.
Active Gap Closure Phase
Once braces are placed, the orthodontist uses the archwire along with elastic chains (power chains), coil springs, or individual ligatures to pull teeth together and close the space. Power chains, which are connected elastic links stretched across multiple brackets, are one of the most common tools for closing gaps.
You may begin to see the gap narrowing within 4 to 8 weeks of starting active closure. However, the rate of movement depends on the gap size, root length, bone density, and the overall treatment plan. A small front tooth gap in an otherwise well-aligned mouth may close in a few months. Larger or multiple gaps as part of a full-arch correction take longer.
Alternatives to Traditional Braces
Clear aligners (such as Invisalign) can close many gaps effectively, especially small to moderate diastemas of 6 mm or less. For larger gaps, complex cases, or situations requiring significant tooth movement, traditional braces generally offer more precise control.
For patients who only want to address a single small gap and have no other bite issues, cosmetic bonding or porcelain veneers may be discussed as non-orthodontic alternatives. These options add material to the teeth to fill the space rather than moving teeth together. Your dentist or orthodontist can help you weigh the pros and cons of each approach.
Recovery and Retention After Gap Closure
Gap closure has a higher relapse rate than many other orthodontic corrections. Thorough retention planning is critical.
During Active Treatment
After the gap is visually closed, the orthodontist typically keeps braces on for an additional period to settle the teeth, close any residual micro-spaces, and ensure the bite is stable. Removing braces too early increases the risk of relapse.
Retainer Phase
Retainer wear is especially important after gap closure. Many orthodontists recommend a permanent bonded retainer behind the upper front teeth to prevent the midline diastema from reopening. A removable retainer (clear or Hawley) is often prescribed for nighttime wear on top of the bonded retainer for added security.
If a tongue thrust contributed to the gap, myofunctional therapy (exercises to retrain the tongue posture and swallowing pattern) may be recommended alongside retainer wear to reduce relapse risk.
Long-Term Stability
Research shows that midline diastemas have a relapse rate of up to 50% without proper retention. With consistent retainer wear and, when needed, frenectomy and myofunctional therapy, the long-term success rate improves significantly.
Plan on wearing some form of retainer indefinitely. If your bonded retainer breaks or detaches, contact your orthodontist promptly to prevent the gap from reopening.
Cost of Braces for Gap Teeth
The cost of closing gaps with braces depends on whether you need full orthodontic treatment or a more limited approach. Costs vary by location and provider.
Typical Cost Ranges
Cost depends on the scope of treatment needed.
- Full braces (metal): $3,000 to $7,000 when gap closure is part of a complete orthodontic treatment plan
- Full braces (ceramic): $4,000 to $8,000
- Clear aligners: $3,000 to $7,000 depending on the aligner brand and case complexity
- Limited treatment (minor gap only): $2,000 to $4,000 in select cases where only a few teeth need movement
- Frenectomy (if needed): $200 to $1,200 as an additional procedure
Insurance and Financing
Dental insurance with orthodontic benefits typically covers a portion of braces or aligner treatment, with lifetime maximums usually ranging from $1,000 to $2,500. Some plans have age restrictions for orthodontic coverage.
Most orthodontic offices offer monthly payment plans. HSA and FSA accounts can be used toward orthodontic treatment costs. Ask about available financing options during your consultation.
When to See an Orthodontist About Gap Teeth
Consider an orthodontic consultation if you have a gap between your teeth that bothers you cosmetically or functionally. Specific signs to watch for include: a gap between the front teeth that has not closed on its own by age 13, spaces that are widening over time, food trapping between teeth that causes gum irritation, a lisp or speech difficulty related to tooth spacing, or gaps that have appeared after previous orthodontic treatment.
In children, the American Association of Orthodontists recommends a first orthodontic evaluation by age 7. Early assessment can identify whether a diastema is likely to close naturally or will need treatment.
Find an Orthodontist Near You
An orthodontist can evaluate the cause of your gap and recommend the most effective closure method for your situation. Use the MySpecialtyDentist.com directory to search for board-certified orthodontists near you, view credentials, and schedule a consultation.
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