Braces or Clear Aligners — What Each One Can Actually Move

A tooth sits in bone, attached by a ligament a fraction of a millimetre thick. Sustained light force compresses that ligament on one side, and the bone there resorbs; on the other side it stretches, and new bone forms. The tooth moves into the space its own body has made.

This is why the force has to be light and continuous. Heavy force does not move teeth faster — it damages the ligament and can shorten roots. Both appliances are designed around this biology, and neither can outrun it.

Fixed braces deliver force through a wire engaged in brackets bonded to each tooth. Because the bracket grips the tooth in three dimensions, the wire can push, pull, rotate and tip individual teeth with a great deal of control.

Aligners deliver force through a shell that fits over the whole arch, slightly differently shaped from the current position. The shell squeezes teeth towards the new shape. That works well for some movements and poorly for others, and the difference explains most of what follows.

One consequence of that biology is worth stating early: a tooth that is loose because of bone lost to gum disease cannot simply be moved into line. The support has to be stabilised first, and in adults that assessment comes before any discussion of which appliance to use.

Rotations, particularly of round teeth. A canine or premolar rotated in its socket is difficult for a shell to grip — the aligner tends to slide around it rather than turn it. A bracket bonded to that tooth grips it directly.

Bodily movement, where the whole tooth including the root has to translate through bone rather than tip. Aligners tend to tip crowns while leaving roots behind, which looks corrected from the front and is not corrected at all.

Large space closure, such as after an extraction. Moving a tooth a substantial distance and keeping its root upright as it goes is one of the things fixed appliances do most reliably.

And significant bite correction — where the upper and lower arches meet wrongly rather than the teeth simply being crooked. Fixed braces combined with elastics, and in severe cases with surgery, remain the treatment for that.

Extrusion — pulling a tooth further out of the bone — is the other movement where brackets have a clear advantage. It matters where a tooth sits higher than its neighbours and the gum line follows it, since no amount of restorative work corrects a gum margin that is in the wrong place.

Mild to moderate crowding, which is by a wide margin the most common reason adults seek treatment. Where teeth need to be lined up rather than substantially relocated, aligners produce excellent results.

Spacing and small gaps. Closing diastemas and evening out spacing is well within what a shell can do, and the result is frequently faster than with fixed braces because the movements are small.

Relapse after previous orthodontics, which is extremely common in adults who stopped wearing retainers. The teeth have been in the correct position before, the movements needed are small, and aligners handle it neatly.

And anything where hygiene is a concern. Aligners come out to eat and to brush, so cleaning is unchanged throughout treatment. Fixed braces make cleaning harder at exactly the time it matters most, and decalcification around brackets is a real risk in a patient who does not manage it.

Closing a single central space is among the neatest aligner cases there is. The options for a midline gap include bonding and veneers, and where the teeth themselves are healthy, moving them together removes nothing at all.

The table sets out the practical differences. The compliance row is the one that decides most outcomes and the one least often discussed at the consultation.

Read the last two rows with travel in mind. For a patient who is not local, the visit frequency and the absence of bracket emergencies are practical advantages that outweigh some clinical ones.

This is the most common surprise, and it is worth knowing before committing. Aligner treatment for anything beyond the simplest cases uses attachments — small tooth-coloured composite shapes bonded to the teeth.

They exist because a smooth shell cannot grip a smooth tooth well enough to produce certain movements. The attachment gives the aligner something to push against, which is what makes rotations and extrusions possible at all.

They are tooth-coloured and small, but they are visible at conversational distance, particularly on front teeth. A patient expecting a genuinely invisible treatment and finding a row of small bumps has been under-informed rather than misled.

They are removed at the end of treatment with no damage to the tooth. Nothing is drilled and no enamel is lost — which is worth stating clearly, because it is the main reason orthodontics remains the conservative answer to crooked teeth.

Their number falls as treatment progresses in some plans and rises in others, depending on which movements are scheduled when. Ask to see where they will be placed on the simulation before approving it — front teeth carrying several attachments change how discreet the treatment actually is.

Fixed braces work whether or not the patient cooperates, because they cannot be removed. Aligners work only while they are in, and the required wear is around twenty-two hours a day, every day.

That means removing them only to eat and to clean the teeth. Two hours a day is the whole allowance, and it disappears quickly across three meals, coffee and an evening drink. Aligners come out for anything other than water.

Under-wear does not slow treatment proportionally — it derails it. The next aligner in the series is shaped for teeth that have completed the previous movement, and if they have not, it no longer fits and the sequence stops tracking.

Being honest with yourself about this is the most useful thing you can do at the consultation. A patient who knows they will not manage it is better served by fixed braces, and there is nothing disappointing about that conclusion.

For comparable cases the two are broadly similar, and claims that either is dramatically faster should be treated carefully. Biology sets the pace, and it is the same biology in both.

Simple crowding or relapse commonly resolves in months rather than years with either appliance. Comprehensive treatment involving extractions or bite correction takes considerably longer, often eighteen months to two years, again with either.

What genuinely varies is how much movement is needed, the patient's age — bone remodels more slowly in adults than in teenagers — and, with aligners, wear time. That last factor is the one that produces the wide range in reported durations.

Accelerated protocols exist and their evidence is mixed. The honest position is that a well-planned case moves at a predictable rate, and shortcuts that promise dramatic acceleration are usually selling something other than tooth movement.

Orthodontics is also the treatment least compatible with a fixed travel plan, since it runs across months rather than days. The timetables for other treatments are measured in working days; this one is measured in review points, and it needs planning differently.

Teeth move for life. The ligament and the fibres around each tooth have memory, and without something holding the corrected position they drift back — slowly, over years, and in a way most patients do not notice until it is obvious.

Retention is permanent, not a phase. A fixed retainer is a thin wire bonded behind the front teeth, invisible and requiring only that it is checked periodically. A removable retainer is a clear shell worn at night indefinitely.

Most orthodontic relapse in adults comes from stopping retention, not from failed treatment. Someone whose teeth were straightened at sixteen and are crowded again at thirty-five almost always stopped wearing a retainer at eighteen.

Ask what retention is included before agreeing to treatment. A plan that ends at the last aligner and treats retainers as an extra has left out the part that determines whether the result lasts.

A bonded retainer needs its own maintenance. It collects deposits behind the front teeth where a brush reaches poorly, so cleaning under it with floss threaders or an interdental brush becomes part of the daily routine — otherwise it protects the alignment while quietly costing you gum health.

This is where the practical comparison diverges from the clinical one. Orthodontics takes months, and neither appliance can be compressed into a single trip. What differs is how the months are managed from a distance.

Fixed braces need adjustment every four to eight weeks, and a loose bracket or a poking wire needs attention within days. For a patient living in another country, that is a genuine logistical problem rather than an inconvenience.

Aligners are issued in sets. Several months of aligners can be provided at once, with progress reviewed remotely through photographs, and in-person visits concentrated at the start and at review points.

That is why aligners are usually the more workable answer for international patients, even in cases where fixed braces would be marginally better clinically — how aligner treatment is arranged from abroad sets out the actual schedule.

Plan the review points around trips you were making anyway where possible. Combining an orthodontic review with another treatment visit is common, and it is one of the reasons alignment often runs alongside a longer restorative plan rather than delaying it.

Between the two main options sit two variations on fixed braces, and both are worth knowing about because they solve the appearance objection without giving up the mechanical control.

Ceramic brackets are tooth-coloured and bonded to the front of the teeth like conventional ones. They are far less visible than metal, somewhat more fragile, and the elastic ties can discolour between appointments in patients who drink a lot of coffee.

Lingual braces are bonded to the back of the teeth and are genuinely invisible from the front. They are the most technically demanding option, take longer to adapt to in speech, and are more expensive — but they deliver full fixed-brace control with no visible appliance at all.

For an adult whose case genuinely needs fixed appliances but who cannot accept visible ones, lingual treatment is often a better answer than compromising the plan to fit aligners.

Both carry the same hygiene caution as metal brackets. Anything bonded to the teeth makes cleaning harder, and decalcification — chalky white marks around where the bracket sat, which often fade only partly and sometimes need treating — is the avoidable damage that follows. It is prevented by technique rather than by luck.

The comparison that matters more than braces against aligners is orthodontics against veneers, because that is the decision with irreversible consequences.

Moving teeth removes no tooth structure at all. Attachments and brackets are bonded and removed with almost nothing lost, though interproximal reduction where it is planned does remove a fraction of a millimetre of enamel. At the end of treatment the teeth are in a better position and are otherwise exactly as they started.

Restoring teeth into a simulated alignment removes enamel from every tooth involved, permanently, and commits each of them to being restored for life. On sound unrestored teeth in a young patient, that is a poor trade for a faster result.

Sometimes the answer is both, in sequence: align first, then a small amount of bonding or two veneers to finish shape and shade. That combination usually needs far fewer restorations than the restorative-only plan — as the coverage comparison and the design process both set out.

There is one case where restoration genuinely wins: where the teeth in question are already crowned or heavily filled. Moving a restored tooth into position and then restoring it again achieves little, and rebuilding it directly is both faster and no more destructive than it already is.

Both are priced by complexity rather than by appliance, and a straightforward case costs less than a comprehensive one whichever route is chosen. The number of aligners, or the months in fixed appliances, is what moves the figure.

Aligner treatment carries a laboratory and planning cost that fixed braces do not, because every aligner in the series is manufactured individually from a digital plan. Fixed braces carry more chair time instead, spread across the adjustment appointments.

Additional aligners — refinement sets, issued when the teeth have not tracked exactly as planned — are a normal part of treatment rather than a failure. Ask whether they are included, because it is a common gap in a quoted figure.

Retention should be in the quote too. How orthodontic treatment is quoted sets out the lines a complete proposal contains and what an incomplete one leaves for later.

Ask what happens if treatment runs longer than planned. With fixed braces that means additional adjustment appointments; with aligners it means additional sets. Neither is unusual, and whether either is chargeable should be established at the consultation rather than discovered at month fourteen.

From the records rather than from a preference. A panoramic radiograph, a lateral cephalogram where the bite relationship matters, photographs and a scan of both arches — those establish what actually needs to move and whether it can be moved by a shell.

Where a case is within aligner range, we say so and set out the wear requirement honestly, including what happens if it is not met. Where it is not — significant rotations, bodily movement, large space closure, real bite correction — we say that too rather than accepting a plan that will not deliver.

For patients travelling, the schedule is designed around the trips rather than around a local patient's calendar. That usually means aligners issued in batches with remote review between visits, and it is planned before you commit rather than improvised afterwards.

Retention is part of every orthodontic plan here, not an addition at the end. What is included is written down, alongside the guarantee terms covering materials and workmanship for life, on materials and workmanship, in writing.