One is to make room between your teeth. They are tiny little rubber bands that the ortho slips between your teeth. It doesn't hurt-- just feels like there is something caught between your teeth. When the teeth are moved enough to make way for the metal brackets (that's the part of the braces that go around your back teeth and hold the wire in place) then the expanders simply fall out. If they don't fall out, the ortho just pulls them out. Again, this doesn't hurt at all.

The other type is a palate expander. (Your palate is basically the roof of your mouth.) It is a wire-type device connected to two metal bands that are cemented to your back teeth. This doesn't hurt when it is put in place. Your mom someone has to insert a 'key' in it each day and turn it. It forces your teeth and the roof of your mouth apart, making a LOT more room. After a couple of weeks of turning/expanding, you let it sit for several weeks to give the teeth/palate/jaw time to adjust.... Two of my kids had palate expanders. They never said anything about it hurting. The only thing that bothered them was that sometimes food got stuck under it and the only way to get the food out was to stick your finger up under it and scrape it out.

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