A palatal expander “expands” (or widens) your upper jaw by putting gentle pressure on your upper molars and is used to make the bottom and upper teeth fit together better. It also makes more room for teeth and helps to promote a broader, more aesthetic smile.
Palatal expansion is usually not painful, but you may feel some minor discomfort. It’ll take a little time for you to get used to your appliance, so you may experience difficulty speaking and swallowing for the first day or two.
Adjusting your appliance as directed will ensure you keep on schedule with the rest of your orthodontic treatment plan. It takes about a few weeks to achieve the desired amount of expansion, after which you’ll keep wearing your expander for about six months, giving time for the new bone to form and stabilize. Our team will give you detailed instructions about how to adjust your appliance and can answer any questions you may have about your palatal expander.
Content retrieved from: https://hunterortho.com/blog/2012/07/whats-a-palatal-expander-and-why-would-i-need-one.