I'm assuming you're talking about a teeth guard to prevent grinding? It took my dentist (since fired by me) three tries to make one that fit me. The first one was too small (she had slipped and cracked off a part of the positive mold) and very, very painful to wear. I now have some sympathy for the poor suckers who had braces. I did finally get one that works great, although my last - very expensive but good, dentist actually said the best type to get is a hard plastic style one. For about $1100. So it could be worse...