After orthodontic treatment, many hope their straightened teeth remain perfectly aligned. However, teeth can shift back. This phenomenon, known as dental relapse, is a natural biological process that occurs if proper post-treatment care is not maintained.
The Reality of Dental Relapse
Teeth often move back toward their original positions if retainers are not worn as prescribed. This tendency, termed orthodontic relapse, is a natural physiological response. Significant movement can begin within weeks or months of discontinuing retainer wear, though it can also occur years later. Teeth are always in motion and respond to forces placed on them throughout life.
Why Teeth Shift After Orthodontics
Several biological factors contribute to teeth shifting after orthodontic treatment. The periodontal ligament, which connects the tooth to the jawbone, has an elastic “memory.” When braces move teeth, these fibers are stretched, and once pressure is removed, they tend to pull teeth back to their pre-treatment positions.
Bone remodeling is another process. During orthodontic treatment, bone around the teeth breaks down and rebuilds to allow movement. After braces are removed, this bone needs time to stabilize. If retainers are not worn, the bone and surrounding tissues may not fully adapt, making teeth susceptible to movement.
Ongoing growth and maturation of the jawbones also influence tooth position throughout life. The jawbone continues to undergo subtle changes that can lead to shifts in tooth alignment. Additionally, everyday oral pressures from chewing, swallowing, tongue position, and habits like teeth grinding (bruxism) or clenching exert forces that contribute to tooth movement.
The Essential Role of Retainers
Retainers are designed to prevent teeth from shifting by holding them in their newly corrected positions. This allows the surrounding bone, gums, and ligaments to stabilize and adapt to the new alignment. Consistent wear helps solidify the changes made during orthodontic treatment, ensuring long-term stability.
There are two main types of retainers: removable and fixed (also known as bonded or permanent). Removable retainers, like Hawley retainers or clear plastic aligner-style trays, offer flexibility and can be taken out for eating and cleaning. Fixed retainers consist of a thin wire bonded to the back of the teeth, typically the lower front teeth, providing continuous support. Initial full-time wear, followed by long-term nightly wear, is often recommended to maintain results.
Addressing Post-Orthodontic Movement
If teeth shift after orthodontic treatment due to inconsistent retainer wear, re-treatment options are available. The appropriate course of action depends on the extent of the movement. For minor shifts, a new retainer might be sufficient to guide the teeth back into place. In some cases, a limited orthodontic treatment, such as clear aligners, can correct minor relapse.
For more significant movement, full re-treatment with braces or aligners may be necessary. Consulting an orthodontist is the recommended first step to assess the situation.