Clear Aligners For Gaps In Teeth

Why clear aligners are particularly effective for gaps

Space closure is one of the movements that clear aligners perform most reliably. Aligners apply retraction forces (pulling teeth together) through the tray material — and because the tray fully covers all teeth, force distribution for gap closure is well-controlled. Unlike crowding cases where space must be created, spacing cases already have the space — the aligners simply close it. Mild to moderate gaps (1–5mm per arch) are typically achievable within a short to medium aligner course, depending on bite and whether any bite correction is also needed.

Types of gaps and how they affect the plan

Midline diastema (gap between upper front teeth): common and highly predictable with aligners. Generalised spacing (multiple small gaps throughout the arch): aligners close each space progressively — reliable for mild-moderate cases. Gap from a missing tooth: more complex — may require orthodontic space redistribution before implant or bridge, or closing the space entirely by moving adjacent teeth together. Gap from a previously extracted tooth: similar to missing tooth planning. Tooth-size discrepancy (teeth naturally too narrow for the jaw): aligners alone may not fully close the gap — restorative bonding may be needed to widen small teeth after closure.

The frenum and midline diastema: an important consideration

The upper labial frenum — the small tissue band connecting the upper lip to the gum between the front teeth — can maintain or re-create a midline gap after closure if it is prominent and attaches between the central incisors. For these cases, a frenectomy (minor procedure to reposition the frenum) is often recommended after orthodontic closure. It is done post-closure (not before) so scar tissue forms in the correct position. If you have a visible frenum that meets the teeth in the gap, ask your clinician whether this applies to your case.

Retention is critical for spacing cases

Spacing cases have among the highest relapse rates after orthodontic treatment. Gaps are especially prone to reopening because the teeth are not in natural contact and the forces holding them closed are weaker than the forces pulling them apart. The most secure retention for closed gaps is a fixed bonded retainer directly bonded across the closed space (typically both adjacent teeth). This, combined with nightly removable retainers, provides the best chance of permanent closure. Removable retainers alone, if compliance is inconsistent, will allow spacing to reopen.

When clear aligners are not the best option for gaps

Fixed braces may be preferable for: large gaps (over 6mm) requiring significant tooth movement; gaps from missing teeth where precise space dimensions are needed for implants; cases where gaps are combined with significant bite discrepancy (overbite, underbite, crossbite) that exceeds aligner correction capability; and gum disease cases where spacing is caused by bone loss (periodontal treatment must come first). A restorative dentist working alongside the orthodontist is often needed for missing tooth planning.

Costs for clear aligner treatment for gaps UK 2026

Short-course aligners for a simple midline gap: £1,500–£2,500. Comprehensive aligners for generalised mild spacing: £2,500–£4,500. Comprehensive aligners for complex spacing or bite correction: £3,500–£6,000. Frenectomy (if needed, charged separately): £300–£800. Composite bonding to widen narrow teeth post-closure: £150–£400 per tooth. Retainers (if not included): £80–£150 per arch for Essix. Missing tooth implant after space creation: separate restorative fee — typically £2,500–£5,000 per implant.

Useful related pages

This guide is for general information only. It is not a diagnosis, treatment plan, or substitute for advice from a registered dentist or orthodontist.