A Gap Between Front Teeth During Palatal Expansion: What Should You Do?

Author: Assoc. Prof. Dr. Halise Aydemir, Orthodontic Specialist.

A gap between the two upper front teeth can occur during palatal expansion, particularly with a fixed rapid maxillary expansion appliance. However, its size alone does not show progress or success. Do not increase, reduce or reverse screw adjustments simply because of this appearance. If the appliance becomes loose, breaks or develops another problem, stop adjusting it and contact your orthodontist.

Why can front teeth separate during palatal expansion?

A temporary gap between the upper central incisors may develop as a narrow upper jaw is expanded with fixed rapid maxillary expansion. The British Orthodontic Society's RME patient leaflet describes this as a possible change during treatment. Separation therefore does not always indicate that the appliance is working incorrectly.

Not all expansion methods are the same. Information about fixed RME cannot automatically be applied to a different appliance or tooth movement for another purpose. Ask your orthodontist about your appliance type and expected changes.

Do not try to measure jaw changes by how large or small the gap looks. A larger gap in a friend's treatment does not mean your adjustments should increase. Equally, not noticing a gap does not alone prove failure. Examination and records described in the narrow upper jaw guide help assess the goal; one view of the front teeth cannot replace that assessment.

Why does the gap not represent the whole expansion?

The opening is easy to see, but does not alone represent width relationships across different parts of the upper jaw or the entire bite. Comparing a photograph with the screw schedule cannot establish that the goal has been reached. The clinician considers a wider assessment. Families are not expected to decide the end of active treatment by measuring millimetres at home.

The described fixed RME process also includes a stage when the appliance remains in place to maintain the expansion achieved. A change in the visible gap is therefore separate from decisions to continue activation or remove the appliance. If the gap starts looking smaller, do not interpret this yourself as reversal of expansion; ask what is being monitored at that stage.

This temporary front-tooth gap may narrow or close spontaneously during follow-up, as described in the BOS fixed RME leaflet. Its stated timeframe should not be applied to every expansion method or patient. A smaller gap does not mean expansion is finished, and further orthodontic treatment may still be needed to align the teeth.

This guide concerns a new gap between the upper central incisors during treatment. A pre-existing gap, a space elsewhere or a change with another appliance should not be assumed to be the same situation. Explain which teeth are involved and the treatment stage when you noticed it.

Should screw adjustments change when a gap appears?

Do not change the prescribed plan solely because a front-tooth gap appears. Extra turns to obtain more expansion, or reversing the screw to close the gap, are not substitutes for your individual plan. The amount of activation and the end of the active phase depend on your clinician's instructions.

An expected appearance and an appliance problem are different situations:

What you notice	What to discuss or do
A new gap with no other appliance problem noticed	Report the change and confirm how to continue the current instructions.
A loose or broken appliance, or a faulty activation mechanism	Stop screw adjustments and contact the clinic without waiting for the routine review.
Forgotten instructions or uncertainty about whether the last adjustment was made	Do not compensate by guessing; ask for clarification before the next step.

This table is not a home test confirming appliance integrity. Report uncertainty too. The palatal expansion appliance care guide covers cleaning and other practical details; general information does not change your activation schedule.

Why does noticing a change not authorise a new adjustment plan?

Learn which findings guide your plan and who will communicate any change in instructions. Reporting a change in the front teeth to the clinic is different from changing your adjustment plan yourself.

It is appropriate to ask the clinic whether activation is finished now that a gap has appeared. Deciding that yourself is different. This example is not an activation recommendation. Note both existing instructions and the response about the new change. If you are unsure which instructions are current, clarify before proceeding.

If several people provide care, keep a clear record of the last completed adjustment. Confusion can arise if one changes the plan after seeing the gap while another follows the old schedule. Sharing family responsibilities does not authorise changes to the clinician's plan; it helps everyone understand the same instructions.

Do not place elastics around teeth, use glue or try another appliance at home to close the gap. Discuss appearance concerns with your orthodontist and ask how the gap will be assessed later if needed. Aesthetic concerns matter, but should not lead to home intervention that takes priority over safe monitoring and individual instructions.

How is the gap monitored, and when should the clinic be contacted?

Note when you first saw the gap and the treatment stage. Explaining that a gap appeared today, the last adjustment was yesterday and you are unsure whether the appliance moves helps organise useful information. Share a photograph if requested; do not push or pull the appliance to obtain it.

Ask at review:

• Is this gap an expected change in my treatment?
• Does my active adjustment plan remain the same, and when is the next review?
• At which stage will we assess changes in the gap?
• How should I contact you if the appliance loosens or pain increases?

There is no universal number of days or months for closure. The gap's course and any additional alignment needs should be explained during individual follow-up. Do not try to close it with elastics, remove the appliance or obtain a new device because of appearance concerns.

Increasing pain, marked loosening, breakage or activation problems should not be dismissed using an explanation of an expected gap. Report the problem. Reviews assess the whole treatment plan rather than compare gap photographs alone.

Does a review only compare photographs?

A photograph can help describe change, but cannot alone confirm appliance attachment, the whole bite or treatment goals. The plan and current findings must be assessed alongside the gap. Receiving a response to an image does not cancel a planned in-person review unless you are specifically told so.

Discuss the gap if its appearance concerns you or your child. Asking what is being monitored and when more can be explained about its course makes expectations concrete. Faster closure in another patient's photograph does not set your deadline. A duration in a source cannot be applied to every method and patient.

After receiving new information, note its date and what changed: continuing activation, ending it and needing another assessment are different decisions. Ask about any unclear difference between written and spoken instructions. Do not create your own schedule again in response to a larger or smaller gap.