Diastema is the dental term for a space or gap that develops between two or more teeth, most often noticed between the two upper front teeth. While gaps may be normal during childhood development, their appearance or widening in adulthood indicates several underlying causes. These causes range from structural issues and oral habits to serious underlying health conditions. Understanding the specific reason your teeth are separating is the first step toward effective management.
Developmental and Structural Causes
Gapping can often be traced back to inherent structural differences between the size of the teeth and the size of the jawbone. If the teeth are naturally small, a condition known as microdontia, there may be too much space available for them in a normally sized or large jaw, leading to generalized spacing throughout the arch. This discrepancy is largely genetic, meaning the trait may be seen in other family members.
The absence of certain teeth, a condition called hypodontia, can also create spaces that adjacent teeth shift into, causing gaps elsewhere in the mouth. A common example involves the upper lateral incisors, the teeth next to the two front teeth, which may be undersized or entirely missing, allowing the central incisors to drift apart.
Another structural factor is the labial frenum, the band of tissue that connects the inside of the upper lip to the gum tissue just above the front teeth. If this frenum is oversized or attaches too low between the teeth, it can physically prevent the two front teeth from closing together. This tissue essentially forms a barrier, maintaining or widening the gap between the central incisors.
Functional Forces and Oral Habits
Teeth are held in a delicate balance by forces from the lips, cheeks, and tongue; therefore, repeated, low-level forces from certain habits can cause gradual tooth movement over time. The most common of these is tongue thrusting, which is an improper swallowing pattern where the tongue pushes forward against the back of the front teeth instead of pressing against the roof of the mouth. This constant forward pressure is strong enough to push the teeth apart, resulting in new or widening gaps.
Other prolonged oral habits, while more often seen in childhood, can have residual effects or be present in adults and contribute to gapping. These include thumb sucking, finger sucking, or even improper chewing or lip-biting habits that continuously apply pressure to the teeth. These dynamic forces disrupt the natural equilibrium that maintains tooth position, causing the teeth to migrate slowly. Even an object like a tongue piercing, if habitually placed between the front teeth, can exert enough force to push them apart.
This mechanical movement occurs because the bone surrounding the tooth is constantly remodeling in response to pressure, a process known as orthodontic force. When a foreign pressure consistently pushes the teeth in one direction, the bone on the pressure side resorbs while new bone forms on the tension side. This biological mechanism allows the teeth to shift and create a visible space.
Gapping Caused by Gum and Bone Disease
For an adult noticing their teeth are starting to gap, the most serious possible cause is advanced periodontal disease, commonly known as gum disease. This condition involves chronic inflammation and infection that progressively destroys the supporting structures of the teeth, namely the gums and the underlying alveolar bone. The loss of this foundational bone support is what leads to tooth movement.
When the bone that anchors the teeth is lost, the teeth lose their stability and are no longer firmly held in place, a situation that is often referred to as pathologic tooth migration. The normal forces of chewing, swallowing, and speaking are then sufficient to push the weakened teeth outward or to the side, causing them to fan out or drift apart. This movement results in newly formed or rapidly widening gaps.
Pathologic migration is a common complication in moderate to severe periodontitis, often presenting with signs such as bleeding gums, redness, swelling, and increased tooth mobility. The appearance of new gaps in the front teeth is a strong indicator of active disease that requires immediate professional dental care. Addressing the infection and bone loss is the primary concern, as ignoring these symptoms can lead to further bone destruction and eventual tooth loss.
Treatment Options for Diastema
The approach to closing a gap depends entirely on the underlying cause, which must be accurately diagnosed by a dental professional. If the gapping is a result of structural issues or long-standing habits, orthodontic solutions are often the most comprehensive treatment. Both traditional braces and clear aligner systems apply controlled force to gradually move the teeth together, closing the space over several months to years.
For smaller gaps or for aesthetic concerns related to tooth size, restorative dentistry offers non-orthodontic options. Dental bonding involves applying a tooth-colored composite resin directly to the tooth surface and shaping it to widen the teeth and fill the space. Porcelain veneers, which are custom-made shells bonded to the front of the teeth, can also be used to effectively close the gap by increasing the apparent width of the teeth.
If a large, low-attaching labial frenum is the cause, a minor surgical procedure called a frenectomy may be performed to reduce the size of the tissue band. This procedure eliminates the physical barrier, often followed by orthodontic treatment to fully close the resulting space. If the diagnosis points to periodontal disease, treatment for the infection, such as deep cleaning or surgery, must occur before or alongside any cosmetic or orthodontic procedures to ensure the stability of the final result.