A space or gap between two teeth, most often the upper front teeth, is known medically as a diastema. While some individuals embrace this feature, many seek treatment for cosmetic reasons or to improve oral health. Braces are a highly effective method for closing these dental gaps, using controlled biological mechanisms to physically move teeth together, offering a durable and comprehensive solution for spacing issues.
How Braces Move Teeth Together
The process by which braces close a diastema relies on the biological principle of bone remodeling, which is a continuous cycle of bone breakdown and formation. Brackets are bonded to the teeth and connected by a flexible archwire that applies a light, continuous force. This force is directed to draw the two separated teeth toward a central point, gently compressing the periodontal ligament that surrounds the tooth root.
The compression side of the ligament triggers specialized cells called osteoclasts, which dissolve the alveolar bone, creating a pathway for the tooth to move. Simultaneously, tension on the opposite side stimulates osteoblasts, which deposit new bone material. This coordinated action allows the teeth to gradually shift into their corrected positions while the surrounding bone structure is rebuilt. The constant, precise pressure applied by the archwire ensures the gap is completely closed.
Understanding Why Gaps Form
Diastemas can develop for several distinct reasons, and understanding the cause is important for long-term stability after treatment. One common factor is a mismatch between the size of the jawbone and the size of the teeth, often due to genetic inheritance. If the teeth are too small for the jaw arch, natural spacing can occur between them. Gaps can also be a result of hypodontia, where teeth are congenitally missing or undersized, such as the small, peg-shaped lateral incisors.
A frequent cause of a midline gap is an oversized or low-hanging labial frenum. This small band of tissue connects the inside of the upper lip to the gum tissue between the central teeth. If this frenum is thick or extends too far down, it can physically prevent the teeth from coming together. Persistent oral habits, such as thumb-sucking or a tongue thrust reflex during swallowing, can also exert outward pressure on the front teeth over time, gradually pushing them apart.
Other Ways to Address Space Between Teeth
While braces are highly effective for comprehensive tooth movement, other options exist for addressing spaces, particularly if the gap is small or if the patient desires a faster result.
- Clear aligners: Systems like Invisalign use a series of custom-made, removable trays to apply pressure and gradually move teeth. These are effective for closing mild to moderate gaps and offer a less noticeable alternative to traditional braces.
- Dental bonding: For very small gaps, dental bonding provides a quick, non-invasive solution by using a tooth-colored composite resin. The dentist applies the resin to the sides of the teeth, sculpting it to fill the space and hardening it with a special light, often completing the process in a single visit.
- Veneers: These thin, custom-made shells of porcelain or composite cover the entire front surface of the tooth. They can be made slightly wider to close moderate gaps, also correcting cosmetic issues like shape or color simultaneously.
- Frenectomy: If the labial frenum is the cause of the gap, a simple surgical procedure called a frenectomy may be performed to reduce the size of the tissue, often before or during orthodontic movement to prevent the gap from reappearing.
Maintaining Closed Spaces
The tendency for a closed diastema to reopen, known as relapse, is a major consideration after any form of orthodontic treatment. The periodontal ligament and surrounding bone have a memory and will try to return the teeth to their original, spaced positions. Therefore, a retention phase is mandatory to ensure the long-term success of the closure.
The most effective method of preventing relapse in diastema cases is the use of a fixed, or bonded, retainer. This consists of a thin wire custom-fitted and permanently bonded to the back surface of the front teeth, holding them securely in their new position. Removable retainers, such as a clear plastic Essix style or a traditional Hawley appliance, are also prescribed, often for nighttime wear. However, the continuous presence of the fixed retainer is often the preferred choice for maintaining the stability of a closed gap, especially when the original cause was a persistent soft tissue issue.