Many people who have undergone orthodontic treatment find their teeth have shifted. This can be disheartening and raise questions about needing treatment again. Understanding why teeth move after treatment is the first step toward addressing it. This article explores common reasons for shifting and what steps can restore alignment.
Reasons Teeth Shift
Teeth are not rigidly fixed in the jawbone; they are suspended by the periodontal ligament, a network of fibers that allows for slight physiological movement. This inherent flexibility contributes to subtle shifts over time. A natural phenomenon known as mesial drift also causes teeth to slowly move forward and towards the midline throughout life, contributing to potential crowding. The human jaw and facial bones continue to grow and change, albeit subtly, into adulthood. These ongoing developmental processes can influence tooth alignment, even after orthodontic correction, with the lower jaw sometimes experiencing late growth rotations that impact the lower front teeth.
The most significant factor in post-orthodontic tooth movement is inconsistent or insufficient retainer wear. After braces, teeth have a strong tendency to return to their original positions, a phenomenon called relapse. Retainers stabilize teeth in their new positions while surrounding bone and gum tissues reorganize, a process taking many months to years. Certain oral habits also exert forces on teeth, leading to shifting. Examples include tongue thrust, where the tongue pushes against front teeth during swallowing, or bruxism (clenching and grinding), which applies excessive forces that encourage movement.
Recognizing Teeth Shifting
One of the most direct indicators of shifting is a visible alteration in tooth alignment. This might manifest as new gaps appearing between teeth that were once perfectly aligned. Conversely, teeth that were straightened might begin to overlap or crowd together, particularly in the lower front area.
Changes in how the upper and lower teeth meet when biting down can signal shifting. The bite might feel different than it did immediately after braces were removed. Subtle shifts can make routine oral hygiene more challenging, as flossing might become noticeably more difficult between certain teeth where crowding has increased.
Patients might also experience pressure or mild discomfort. A clear sign of tooth movement is a retainer that no longer fits comfortably or correctly. If a removable retainer feels tight or difficult to put on, it indicates teeth have already shifted from their ideal positions.
What to Do About Shifted Teeth
The first step upon noticing shifted teeth is to schedule an appointment with an orthodontist. A thorough examination will allow the professional to assess the movement and determine its underlying causes. They can then recommend the most appropriate course of action.
For many cases of minor to moderate relapse, clear aligners are a common and effective solution. These custom-made, removable plastic trays gradually move teeth back into their desired positions. Patients wear a series of aligners, changing them every one to two weeks, offering a discreet treatment option.
Sometimes, only a few teeth have shifted significantly, making a full set of braces unnecessary. Limited orthodontic treatment, often involving traditional braces or clear brackets on a segment of teeth, can address specific areas. This approach is quicker and less extensive than comprehensive treatment.
For very minor shifting, a new custom-made removable retainer, worn consistently, might guide teeth back into a slightly better position. This is effective for subtle movements and is often used for maintenance after re-correction.
For minor cosmetic issues where shifting is minimal and affects the appearance of a single tooth, dental bonding or porcelain veneers might be considered. These restorative options reshape or cover a tooth to improve its aesthetic alignment without moving the natural tooth structure, though they do not address the underlying tooth position.
In cases of significant relapse or complex bite issues, comprehensive orthodontic treatment, including traditional braces or clear aligner therapy, may be recommended. This ensures complete correction of alignment and bite.
Preventing Future Shifting
Consistent, lifelong retainer wear is crucial for maintaining orthodontic results. Orthodontists recommend wearing removable retainers full-time for a period, usually six to twelve months, followed by nightly wear indefinitely.
There are two main types of retainers: removable and fixed. Removable retainers, such as Hawley or clear Essix retainers, are worn for prescribed hours each day. Fixed retainers, also known as bonded or permanent retainers, are thin wires cemented to the back surfaces of the front teeth, providing continuous stabilization.
Periodic visits to the orthodontist, even after treatment, can help monitor tooth stability and retainer fit. These appointments allow for early detection of shifts and retainer adjustments, preventing significant relapse. Managing habits like teeth grinding, clenching, or tongue thrust also contributes to long-term stability.