A widening gap between teeth, medically known as a diastema, often prompts a visit to the dentist. While a gap is simply a space, its enlargement in an adult signals a disruption in the balance of forces holding the teeth in alignment. Teeth are not rigidly fixed; they are held in place by bone and soft tissues, allowing for continuous, slight movement. Understanding this change requires investigating the factors that exert pressure or reduce support around the teeth.
Anatomical Factors and Oral Habits That Widen Gaps
One common anatomical contributor is the labial frenum, a band of tissue connecting the inside of the upper lip to the gum tissue above the two front teeth. If this frenum is unusually thick or attaches too low, it can physically prevent the front teeth from moving closer or exert a pulling force that separates them. This is particularly true if the attachment extends into the interdental papilla.
Muscle function and persistent habits also generate constant, low-level forces that can push teeth apart. Tongue thrusting, or reverse swallowing, involves the tongue pressing against the back of the front teeth during the swallowing reflex instead of resting on the roof of the mouth. Since a person swallows hundreds of times a day, this repetitive pressure slowly pushes the front teeth outward, creating or enlarging a gap.
Other persistent oral habits contribute to unwanted tooth movement by applying sustained force. These include chronic lip biting, nail biting, or habitually chewing on objects like pens or pencils. Although the force exerted by a single instance is small, the cumulative effect over time can cause the slow migration of teeth and widen an existing diastema.
Periodontal Health
The most serious cause of a progressively widening gap is the deterioration of supporting structures due to advanced periodontal disease (periodontitis). Teeth are firmly anchored in the jawbone by periodontal ligaments and alveolar bone. Periodontitis is an infection that causes inflammation, which, if untreated, leads to the gradual destruction and resorption of the supporting bone.
When bone and ligament support is compromised, teeth become less stable and more susceptible to the normal forces of chewing and swallowing. This loss of structural integrity results in pathological tooth migration, where teeth shift out of their normal position, often flaring outward or creating new spaces. Studies indicate that pathological migration is a common finding in patients with moderate to severe periodontitis.
A widening gap, along with symptoms like bleeding gums, increased tooth mobility, and gum recession, signals that the underlying disease needs immediate attention. The loss of bone support makes the teeth loose, and the pressure from inflamed gum tissues contributes to drifting. Addressing the infection and stabilizing the bone is necessary to halt this destructive process.
Mechanical Shifts Caused by Missing Teeth or Dental Work
The dental arch is an interdependent system, meaning a change in one area affects the alignment of teeth elsewhere. Losing a tooth, especially a back molar that maintains arch integrity, can trigger a mechanical cascade of movement. The remaining teeth drift and tilt into the newly created space, which can ultimately push the front teeth apart.
This shifting disrupts the established bite and creates unstable pressure points. Failing to replace a missing tooth allows this domino effect to continue, leading to misalignment and the enlargement of existing gaps. Replacing the missing tooth with an implant or bridge is important to restore stability and prevent further collapse.
Improperly fitted dental work can also introduce mechanical forces that cause subtle, persistent tooth movement. A crown, filling, or bridge that is slightly too “high” creates premature contact when biting down, exerting excessive pressure on the tooth and its neighbors. This constant, unbalanced force leads to the slow movement of teeth, manifesting as a widening gap or general bite misalignment.
Next Steps for Diagnosis and Treatment
If a gap is widening, the first step is a comprehensive examination with a dental professional to accurately diagnose the underlying cause. This consultation typically includes a visual inspection, periodontal probing to check gum health, and X-rays to evaluate supporting bone levels. Determining the exact cause is necessary to establish an effective treatment plan.
Treatment depends entirely on the specific diagnosis. If periodontal disease is identified, the initial focus must be on deep cleaning procedures, such as scaling and root planing, to control the infection and stabilize the bone. Once the foundation is healthy, the gap can be addressed with orthodontic treatment like braces or clear aligners.
For gaps caused by an anatomical issue like an oversized frenum, a minor surgical procedure called a frenectomy may be performed to release the restrictive tissue. If the widening is solely a cosmetic concern, a dentist may use dental bonding or veneers to close the space. Ignoring a widening gap is not advisable, given the potential link to serious gum health issues.