Diastema (Gap Teeth) Treatment UK

What is a diastema?

A diastema is a space or gap between two adjacent teeth. While it can occur anywhere in the mouth, the most clinically significant and most commonly noticed diastema is the midline diastema — a gap between the upper two central incisor teeth. Small diastemas of 1 to 2 mm are common and, in the absence of any functional problem, may not require treatment. Larger gaps — particularly those over 2 mm — are more noticeable aesthetically and are more frequently the reason patients seek orthodontic or cosmetic dental advice.

What causes a gap between front teeth?

The most common cause of a midline upper diastema is a prominent or low-attaching labial frenum — the band of tissue between the upper lip and the gum between the front teeth. A second major cause is tooth-size discrepancy, sometimes called Bolton discrepancy, where the upper teeth are proportionally smaller than the lower teeth, creating space that cannot be fully closed by tooth movement alone. Hypodontia — congenitally missing teeth — can cause spacing throughout a dental arch. Tongue thrust habits, periodontal disease causing bone loss, and genetics also play roles.

What are the treatment options for a diastema in the UK?

For a frenum-related diastema, orthodontic closure with fixed braces or clear aligners is the primary treatment, followed by a bonded fixed retainer and possibly a frenectomy. For small diastemas of 1 to 2 mm with a good bite, composite bonding — where tooth-coloured resin is applied to the edges of both teeth — can be an effective, quick, and relatively low-cost solution. For moderate diastemas of 2 to 4 mm, composite bonding alone may widen the teeth beyond natural proportions, so orthodontic closure first followed by small composite additions is often the best combined approach.

When is a frenectomy needed and what is the correct timing?

Not all prominent frenula need to be removed. Assessment involves examining how low the frenum attaches and whether a blanch test confirms a problematic attachment. If a frenectomy is required, timing relative to orthodontic treatment matters. The standard approach is to close the diastema orthodontically first and then perform the frenectomy after closure while the teeth are still in a retainer. The scar tissue formed by the frenectomy becomes the retention tissue, helping to hold the teeth in their closed position.

How high is the relapse risk after diastema closure?

Diastemas carry one of the highest relapse risks of any orthodontic tooth movement. The fibres of the periodontal ligament and the supracrestal fibres retain elastic memory and actively pull teeth back towards their original position. Without long-term retention, a closed diastema will commonly reopen within months to years. A bonded fixed retainer — a thin wire cemented to the backs of the upper front teeth — is considered mandatory by most orthodontists following diastema closure. Removable retainers alone provide insufficient protection for midline diastemas.

What does composite bonding versus orthodontic closure mean for aesthetics?

Orthodontic closure physically moves the teeth together, preserving their natural size and shape, and is the more conservative treatment for larger gaps. Composite bonding adds material to the teeth to fill the gap without tooth movement and can produce excellent results for small diastemas. When bonding is used to close a gap, the width-to-length ratio of the affected teeth changes, and if too much resin is added the teeth can look overly wide. Bonding also requires maintenance — composite stains, chips, and may need polishing or replacement every five to ten years.

What does diastema treatment cost in the UK?

Composite bonding to close a small diastema costs approximately £200 to £600 per tooth, so between £400 and £1,200 for the two upper central incisors. Orthodontic treatment to close a larger gap costs £2,000 to £5,000 depending on the type of treatment and practice. A frenectomy adds a further £300 to £700 if required. A bonded fixed retainer following treatment typically costs £150 to £350 and forms part of the retention package at most practices.

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.