In
orthodontics, a
hyrax is a large piece of metal stuck in the roof of the
mouth. A hyrax has dial that is turned with a
key, to widen the upper arch of your mouth so that
braces can be put in later. The hyrax is usually attached to the backside of the last two
brackets on either end of your mouth.
The orthodontist will prescribe the number of times daily for the hyrax to be turned, and for how many days. After that, they use a sealant to keep it from being turned any more, but the hyrax usually stays in for about a year.
When the dial on the hyrax is turned, your teeth will feel very loose. But it also gives you a world of hurt for a while afterward.
They have several awful side effects. The first two weeks I had mine in, I couldn't eat any kind of meat; food would always get stuck between the top of the hyrax and the roof of my mouth (and it's a great deal of trouble to get anything stuck in that spot out). Friends of mine that had the same work done told me of tingling sensations after getting the hyrax turned, though I never experienced that. The biggest complaint I had with it was one that wouldn't go away, ever.
I couldn't enunciate. Throughout the first month I always spoke as if my tongue had swollen to massive sizes, and after that any "e" sound came out sounding very awkward and unnatural. I never felt self-conscious about having the braces, but I was very aware of the way it made certain words sound. Fortunately, the problem went away as soon as I got it removed, and I could articulate clearly.
Avoid this treatment like the plague, if you can.