One-Arch Treatment: Can You Get Aligners for Just Top or Bottom Teeth?

It is a reasonable question and a very common one. The lower front teeth are crowded but nobody sees them; the upper front teeth show when you smile and those are the ones you would like corrected. Why treat both?

Single-arch treatment is a legitimate approach and it is used. But whether it suits your case is decided by something that is not visible when you look in the mirror: how your upper and lower teeth meet.

Teeth do not sit in two independent rows. Every upper tooth has a relationship with the lower teeth it contacts, and that relationship governs how the jaw closes, how it moves side to side, and how force is distributed.

Move the upper front teeth backwards to close a space, and they now sit further back relative to the lower teeth — which may be fine, or may mean they now collide with the lowers when you close. Move the lower front teeth forwards to relieve crowding, and they may now hit the backs of the upper teeth.

The alignment you can see is one variable. The bite is the constraint. An orthodontic plan that ignores it can produce teeth that look straight and meet badly, and a bad bite produces wear, fracture, tooth mobility and sometimes muscle and joint symptoms.

Our article comparing aligners with fixed braces covers how treatment is planned more generally.

Single-arch treatment is more likely to be appropriate where:

The bite is already good, and only one arch has a problem. If the teeth meet well and the issue is confined to mild crowding or a small rotation in one arch that can be corrected without changing the bite relationship, one arch may be all that is needed.

The movement required is small and confined within the arch. Derotating a single tooth, closing a small space, or relieving slight crowding using interproximal reduction — creating space by reducing the width between teeth very slightly — can often be achieved without altering how the arches meet. Our article on how long aligners take for minor crowding covers the simpler end of the spectrum.

It is relapse after previous treatment. Where teeth were previously in a good bite and one arch has since drifted, returning that arch to where it was may restore the original relationship. This is one of the more common genuine indications.

The other arch is restored or not movable. Where the opposing arch has extensive crowns, bridgework or implants, moving it may not be practical, and treatment is planned around it.

The opposing arch has already been treated at an earlier stage.

There is an existing bite discrepancy. A deep bite, an open bite, a crossbite, a significant overjet or a mismatch in how the back teeth meet all involve the relationship between the arches. These cannot be corrected by moving one arch alone.

Space needs to be created by expansion or by moving teeth backwards. Both change the arch relationship.

The midlines do not match. Correcting a midline discrepancy generally requires coordinating both arches.

The upper teeth need to come back and there is nowhere for them to go. If a deep bite means the lower teeth already contact the upper front teeth, retracting the uppers will worsen the contact. The lower arch usually has to be addressed as well.

Crowding is significant. Relieving crowding requires space, and where that space is created by proclining teeth forwards, the relationship with the opposing arch changes.

There is wear from the way the teeth meet, which is a functional problem rather than an aesthetic one.

The lower arch is crowded and will continue to crowd. Lower incisor crowding tends to progress over time. Treating only the upper arch leaves the underlying issue untouched, and the lower teeth continue to move. Our article on hidden crowding and why lower teeth shift first covers this.

The teeth look straight but do not meet properly. The most common poor outcome, and one that can be uncomfortable and produce uneven wear.

A single tooth ends up carrying the bite, which causes tenderness, mobility and sometimes fracture. Our article on occlusal adjustment in crowns covers how sensitive the bite is to small discrepancies.

Interferences during jaw movement, producing muscle ache and joint symptoms. See TMJ treatment.

Relapse, because the corrected arch is not stabilised by a compatible bite.

The result looks unbalanced, because the untreated arch's irregularities become more noticeable next to the corrected one.

Treatment stalls partway through when it becomes clear that the planned movement cannot be achieved without addressing the other arch — at which point the treatment plan and the cost both change.

Before single-arch treatment is agreed, the assessment should include:

• How your teeth meet, front and back, in closing and during side-to-side and forward movement

• Overbite and overjet measurements

• Whether there are any crossbites

• Midline position relative to the face

• Periodontal health — teeth cannot be safely moved through inflamed or unsupported bone, and this is a genuine risk with treatment planned without an examination. Our article on why quality matters in adult orthodontics covers this

• Radiographs to check root position, bone levels and any undiagnosed pathology

• Existing wear patterns, which reveal how the bite has been functioning

• A digital treatment plan showing the projected final position of both arches, not just the one being treated

A plan that shows you a simulated result for one arch without demonstrating how it will meet the other is not a complete plan.

Two motivations usually sit behind the question, and both deserve a straight answer.

Cost. Single-arch treatment is generally less expensive, and that is a legitimate consideration. But treatment that produces a bite problem is not a saving. If the assessment shows one arch is appropriate, the reduced fee follows naturally; if it does not, treating one arch to save money is a poor trade. Our article on what affects the cost of braces covers the fee structure, and our pricing page sets out current fees.

Time and convenience. Fewer aligners and a shorter course. Again, real — but only if the plan works.

Whatever is treated, retention applies to the result. Teeth move throughout life, and a corrected arch will drift back without retention.

Where only one arch has been treated, retention of that arch is essential — and it is worth discussing whether the untreated arch should also be retained, since ongoing movement there can affect the corrected arch over time. See fixed retainers and our article on retainer costs and replacements.

Can I have aligners for just my top teeth?

Sometimes. It depends on how your teeth meet and on how much movement is needed. It is a clinical decision made after examining the bite, not a matter of preference alone.

Will treating one arch cost less?

Generally yes, since fewer aligners and less clinical time are involved. Whether it is appropriate is a separate question.

My lower teeth are crowded but I do not care how they look — can I ignore them?

Possibly, if the bite allows and the crowding is not affecting function or cleaning. Crowded lower teeth are harder to clean and tend to crowd further over time, so it is worth discussing the longer view.

What if I start with one arch and then need the other?

This happens, and it is usually manageable, but it extends treatment and changes the cost. A thorough plan at the outset reduces the chance of it.

Is single-arch treatment less stable?

It can be, where the corrected arch is not supported by a compatible bite. Retention is important in all cases and particularly here.

Can remote aligner services do single-arch treatment safely?

Treatment planned without an in-person examination, radiographs and a periodontal assessment carries real risks, and bite assessment in particular cannot be done properly at a distance.

Whether one arch is enough is answered by examining how your teeth meet — which takes a consultation, photographs, scans and usually radiographs. That assessment is what turns the question into a plan.

You can contact our team at our Wimpole Street practice, or read about proaligner treatment.

This article provides general information about single-arch orthodontic treatment and does not constitute individual dental advice. Suitability depends on your bite, periodontal health and the movement required, all of which need clinical assessment. Wimpole Dental is regulated by the Care Quality Commission, and our clinicians are registered with the General Dental Council.

Next review due: 14 September 2027