Clear aligners straighten teeth through a series of removable trays, each slightly different from the last. Understanding how that works makes the treatment, and its requirements, easier to judge.
The mechanism
Teeth sit in bone, held by a ligament. Sustained gentle pressure causes the bone on one side of the root to remodel away and new bone to form on the other, so the tooth migrates. This is the same biological process used by braces; aligners simply apply the force differently.
Each tray is made to a position marginally ahead of where the teeth currently are. Worn consistently, it applies light continuous pressure until the teeth catch up, at which point you move to the next tray.
Why wear time decides the outcome
Bone remodelling needs sustained force. Intermittent pressure allows teeth to drift back between wears, so progress stalls. Aligners are generally worn 20 to 22 hours a day, out only for eating, drinking anything other than water, and cleaning.
This is the single biggest factor in whether treatment finishes on schedule. Aligners cannot work while they are in a pocket.
Attachments and why trays alone are not always enough
Some movements, particularly rotating round teeth or moving a tooth bodily rather than tipping it, are difficult for a smooth tray to grip. Small tooth-coloured attachments are bonded to certain teeth to give the aligner something to push against. They are removed at the end of treatment.
What aligners handle well, and less well
- Well: crowding, spacing, tipped teeth, mild to moderate alignment problems, and relapse after previous orthodontic work.
- Less well: large bite discrepancies, teeth needing significant vertical movement, and complex cases that may be better served by fixed braces or a specialist referral.
Planning
Treatment starts with records: photographs, a digital scan and usually X-rays. From these a plan is produced showing the intended sequence of movements and roughly how many trays will be needed. You can see the projected end position before committing.
Retainers are not optional
Teeth have a tendency to drift back towards where they started, most strongly in the months immediately after treatment while the bone is still settling. Retainers hold the result. Stopping retainer wear is the most common reason people find their teeth moving again years later.
Through treatment
Trays are typically changed every one to two weeks, with periodic reviews to confirm the teeth are tracking as planned. If they are not, the plan is adjusted, which is routine rather than a setback.
Related treatment
Read more about clear aligner treatment in Bendigo.
This article is general information only and is not a substitute for an individual dental assessment.