What is a palate expander?

What does a palate expander do?

Cleveland Clinic says a palate expander widens a narrow upper jaw. It applies gentle, steady force to each side of the palate, slowly moving the two halves of the jawbone apart, and new bone fills the space left behind. Colgate says it is most often recommended for a crossbite between the upper and lower teeth, or when there is not enough room for permanent teeth to come in correctly.

What are expanders for teeth made of, and what types exist?

Colgate describes a custom-made plate cemented or bonded to several upper molars, with two halves joined by a central screw. Cleveland Clinic describes a rapid expander with a central screw that is turned with a special key, and a removable expander that looks like a retainer and is used for smaller adjustments. A rapid expander is the one most families mean when they talk about a palate expander, and the plan's hub covers how to turn it.

Who needs a palate expander?

Cleveland Clinic lists crowded, overlapping or crooked teeth, impacted teeth, difficulty chewing and bite problems such as a crossbite, open bite, overbite or underbite, and says it may help some people with obstructive sleep apnea. It says orthodontists often suggest starting around ages 7 or 8, and that teens and adults can have one but may need up to a year. Colgate says it works best for children and preteens whose mouth bones are still growing.

What is a space maintainer?

A space maintainer is a different appliance. The Cureus review describes the purpose of space maintenance, citing American Academy of Pediatric Dentistry guidelines, as preventing the loss of arch length, arch width or arch perimeter, preserving space for the permanent teeth and preventing malalignment after a baby tooth is lost early. The review does not give a formal definition, and neither Cleveland Clinic nor Colgate mentions space maintainers. Dentists place one when a baby tooth is lost early to decay or injury, which is general knowledge and flagged.

Does a child always need a space maintainer?

Not necessarily. The 2025 systematic review looked at early loss of the upper first baby molar in children aged 5 to 10 and found significant space loss at six months compared with the control side, but also found that the effect on arch perimeter, width and length was not significant, which the authors attribute to neighbouring teeth moving into the space. They consider a space maintainer questionable, especially when the first permanent molar has already erupted, and say it may be useful for mild crowding at the front. Decisions, they say, should weigh age, time since extraction, facial pattern and molar relationships. The review had few studies and short follow-up.

What is the difference between the two?

An expander makes more room by widening the jaw. A space maintainer keeps the room that is already there. They treat different problems, and a child may have neither, one or both over time. Because both sit in the mouth and both need cleaning, the care advice is similar: brush around the device after meals and avoid sticky foods.

Does it hurt?

For an expander, Cleveland Clinic says minor discomfort is common for the first few days and the device should not cause severe pain. Colgate describes pressure below the eyes or at the top of the nose after a turn. The sources we read do not describe discomfort with space maintainers. Our hub on palate expanders covers eating, speech and cleaning in more detail.

Is a gap between the front teeth normal?

Colgate says a gap between the front teeth is normal during expansion and is later closed with braces. Cleveland Clinic says some people develop gaps between their front teeth, which orthodontics can correct later. Neither describes it as a sign that something has gone wrong.

Questions to ask the dentist

Take these to the appointment.

• Does my child need an expander, a space maintainer or neither?
• What problem will it fix, and what happens if we wait?
• How long will it be in?
• Will braces be needed afterwards?
• How should we clean and look after it?

Frequently asked questions