Midline diastema is a dental term describing a space or gap between the two upper front teeth, known as central incisors. It is a common dental feature in both children and adults. The size of these gaps can vary from barely noticeable to prominent.
Causes of a Midline Diastema
A midline diastema can arise from several factors, from natural developmental stages to underlying dental issues. In children, a temporary gap often occurs during the “ugly duckling stage” (ages 7-12) as permanent teeth erupt. During this phase, developing permanent canines can push central incisors apart, creating a temporary space that usually closes as the canines fully emerge.
Another cause involves a discrepancy between tooth and jawbone size. If teeth are small relative to the jaw, or the jaw is larger than average, extra space can exist, leading to gaps. This size mismatch can be influenced by genetic factors, as a predisposition to diastema can be inherited.
The labial frenum, a fold of tissue connecting the upper lip to the gum above the front teeth, can also contribute to a midline diastema. If this frenum is oversized, thick, or attaches too low, it can prevent the central incisors from coming together. A blanch test, where the upper lip is pulled outward, can help indicate if a high frenal attachment is a factor.
Certain oral habits can exert pressure on teeth, leading to or worsening a diastema. Persistent thumb sucking, especially beyond early childhood, can push the front teeth forward and apart. Tongue thrusting, an atypical swallowing pattern where the tongue presses against the front teeth, can also contribute to gap formation over time.
Underlying dental issues can also cause tooth shifting and gaps, particularly in adults. Missing teeth, such as lateral incisors, can create space into which adjacent teeth may drift, resulting in a diastema. Advanced gum disease (periodontitis) can lead to bone loss around teeth, causing them to loosen and move apart, forming new gaps.
When a Diastema Is a Concern
While a midline diastema is a common and often harmless dental feature, certain indicators may suggest a need for professional evaluation. For many children, the gap is a normal part of development and typically closes naturally as permanent canines erupt (ages 9-11). This self-correction means early intervention is often unnecessary unless specific issues are present.
A dentist may become concerned if the diastema is excessively large or persists after all permanent adult teeth have emerged (generally by age 12-15). If the gap is wider than 2 millimeters after permanent canine eruption, spontaneous closure is less likely, suggesting intervention. Beyond cosmetic considerations, a diastema can sometimes impact speech, leading to phonetic problems like lisping, particularly with wider spaces.
A diastema warrants a dental visit if caused by or accompanied by signs of gum disease, such as pain, redness, swelling, or loose teeth. Gum disease can damage supporting bone structure, leading to tooth movement and gap formation, requiring immediate periodontal treatment to prevent further complications. If the gap results from missing teeth or other dental anomalies, a professional assessment helps determine the underlying cause and appropriate action.
Treatment Options for Closing a Gap
When a midline diastema causes functional or aesthetic concerns, various professional treatments are available. Orthodontic treatment, using traditional braces or clear aligners, is a common and effective method to move teeth together. Braces involve brackets and wires that apply continuous pressure to gradually shift teeth into alignment, while clear aligners use a series of custom-made, removable trays for similar results. Orthodontic treatment can address discrepancies in tooth and jaw size and correct overall bite alignment.
Cosmetic dentistry offers solutions for closing gaps without extensive tooth movement. Dental bonding involves applying a tooth-colored composite resin directly to the teeth adjacent to the gap, shaped and hardened with a special light to fill the space. This procedure is quicker and less expensive, often completed in a single visit, though the material may be susceptible to staining. Porcelain veneers are thin, custom-made shells bonded to the front surface of teeth to cover the gap and improve appearance. Veneers are more durable and stain-resistant than bonding, but they often require enamel reduction and are a more significant investment.
A frenectomy is a minor surgical procedure recommended if an oversized or low-attaching labial frenum contributes to the diastema. This procedure involves removing or repositioning the tissue to reduce its pull on the teeth. In younger children, a frenectomy alone might allow the diastema to close naturally as permanent teeth erupt. For older children and adults, it is often performed with orthodontic treatment for successful and stable gap closure.
If a diastema is not causing health issues like speech problems or gum disease, and the individual is not bothered by its appearance, choosing no treatment is an acceptable option. Many people embrace their natural tooth spacing as a unique characteristic. A gap that is solely a cosmetic feature does not necessitate intervention. Ultimately, the decision to treat a diastema depends on its underlying cause, its impact on oral health and function, and personal aesthetic preferences.