The day you got your braces off (or finished your final aligner) was a dream come true. After months—or maybe even years—of treatment, those pearly whites were perfectly straight. You had your perfect smile, and that was that.
Until months (or years) later when your newly straightened smile is no more. That front tooth is shifted. A small gap has formed that hadn’t been there before. The bottom teeth—which used to be perfectly aligned—now overlap ever so slightly. It’s disappointing, frustrating and confusing. The treatment worked, so why don’t the results last?
Teeth shifting post-orthodontic treatment is distressingly common. According to some findings, upwards of 70% of individuals experience orthodontic relapse post-braces/aligners. Understanding why this occurs—and what helps prevent it—makes all the difference in securing that straight smile for life versus watching it slowly fade away.
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Your Teeth Remember
The truth about teeth? They want to move back to where they came from. While that sounds a bit disconcerting, teeth really do have memories. The periodontal ligament (the tissue responsible for holding the teeth in position in the jaw) has elastic properties. When treatment establishes new alignment, these ligaments attempt to pull the teeth back into their original positions.
This force is most powerful during the first year following orthodontic treatment, which is why retention during this time is critical. The ligaments need time to readjust and stabilize now around the new positional configuration of the teeth. If retention isn’t implemented in this time frame, teeth will shift back into their original places—and quickly. Some individuals notice their teeth shifting back within weeks of forgoing their retainers.
There’s good news, however. The ligaments aren’t able to maintain such a strong hold on the original position over time—they weaken and dissipate as time goes on. Therefore, though people report shifting well into adulthood, it’s clear that after that first year, it’s not as bad—albeit, still annoying. Essentially, per the research above, retention is for life.
The Retainer Obsession
The most common reason for orthodontic relapse is simple: failure to wear retainers. Ironically, this is a major factor in the initial transition period coming out of braces/aligners—people do not want to feel like they’re wearing something for life after they’ve just been through a substantial process.
Consider this typical pattern: someone gets their braces off and is given retainers. They wear them diligently for a few months. Then they skip a night here or there. Soon they’re only wearing them two or three times a week. Eventually, the retainers sit in a drawer but consolation lies in believing that they’ll eventually get back to it. Except when they finally do, the retainer doesn’t fit—because the teeth have moved since they last wore it.
The truth about teeth is that they shift gradually; so gradually that they can majorly shift before someone even realizes it’s happening. A gap that took months to close can reopen in less than a week without proper retainers for teeth worn nightly for years.
Get Your Wisdom Teeth
While wisdom teeth are one of many reasons for orthodontic relapse, they’re not the primary concern; however, they can definitely be an aggravating factor. When wisdom teeth erupt—typically during teenage years through young adulthood—they can crowd the front teeth by pushing them forward as there’s not enough room for everything.
This is notably obvious with the bottom front teeth. Many adults who had perfectly straight bottom teeth find slight crowding or overlapping in their 20s—which just happens to be around the time when wisdom teeth erupt (if they haven’t been removed by then). The force from the wisdom teeth trying to erupt—with insufficient room—pushes the adjacent teeth together to make space for themselves.
That said, even adults without wisdom teeth can observe adult crowding; it’s not necessarily an attribute associated with tooth shifting attributable only to wisdom teeth. It’s simply how the jawline narrows as we age—even if we had wide mouths and healthy spacing before transitioning throughout adulthood.
Aging and Movement
Whether people have had braces or not, tooth movement is normal over time. The jaw continues to shift into its final positioning through ages 20-29 and beyond while bone density decreases as we age as well as changes with further maturation.
Therefore if someone expects their perfectly straight smile after their orthodontic treatment at age 15 to stay that way at age 25 (or beyond), without some form of retention they’re sorely mistaken. This isn’t realistic.
Movement rates vary significantly, too; while some individuals may have minimal shifting and teeth remain relatively stable, others note extreme movement within weeks of foregoing their retainers. There’s no predictability about it until people experience it themselves; therefore, this fact can either be comforting or disconcerting for any individual.
Habits
Think about your tongue; it’s constantly exerting pressure against your front teeth in one form or another—including during swallowing (should you tongue thrust). It exerts pressure against other teeth as well—nail biting often highlights significant downward or lateral movement when biting becomes habitual; clenching or grinding further adds pressure as does any outside forces resulting from lifestyle changes—stressful periods may induce grinding when previously it had been negligible.
Oral habits develop primarily in stressful situations—when someone finds themselves biting their nails or grinding their teeth in adulthood by accident but hadn’t done so as a child when retaining children should’ve already stabilized themselves.
The Type of Case
Certain orthodontic needs are more easily retained than others. For example, simple cases where all that required attention was some slight shifting tend to stay more easily than rotated or expanded cases.
Rotated teeth are highly susceptible to movement after they’ve been rotated into place due to the twisting of periodontal fibers around the tooth’s root. These fibers attempt to untwist and consequently, shift rotated teeth back into place at their initial positions for years after treatment.
In addition, very crowded cases tend to relapse more easily due to jaw size not changing with age; instead, the teeth were repositioned within the available space but without retainers allowed—even with aging—they often crowd back together again.
How To Avoid Relapse
The best way to prevent relapse from occurring is by wearing a retainer consistently until stabilization occurs. For most people, this means nighttime wear for life—and for those who wish for limited wear during adulthood, they may benefit from bonded retainers (thin wires that are glued to the backs of important teeth) used temporarily in tandem with removable retainers for the remainder of the mouth.
However, if relapse does occur, it depends on how far and when. Minor relapses often occur due to a few weeks without a retainer but that’s fine—the retainer can be more consistently worn to establish prevention—but if major relapse occurs either due to severe periods without a retainer or extended time without one, some form of retreatment occurs—months with aligners or limited braces/whatever it takes to move them back into position.
What’s important is addressing the issue as soon as possible—the longer compounded shifted teeth are left untreated, the more severe it becomes to correct and the pricier it gets. A minor gap that reopened could’ve been corrected in a few months’ time but once too much time accumulates it’s no longer tenable without full retreatment.
Retention Is For Life
This is ultimately what no one tells you: retention isn’t temporary—for most people who want to maintain straighter smiles at permanent achievement following orthodontic retention requires somewhat of retention for life after treatment.
For some people they can reduce retention period down once they start stabilizing but that’s only after several months/years down the road once the body adjusts with periodontal ligaments stabilizing around the new positions; others choose permanent options like bonded retainers in key spots of discretion.
Ultimately it’s important to find a system that works over time; it’s often easier said than done unless someone can practice a little while longer with more than previously thought possible until it’s too late; thus ensuring you have your perfect smile means achieving it first—and then continue ensuring your perfect smile is just that because it’s no longer perfect unless it’s maintained without a little consistent effort (but none too bad).
