Depends what type of brace or appliance you are going to have. I you have an plate or removable appliance definitely not, because they have to be made especially for your mouth and each are...
Well when you first get them on it dosent. But the next morning you wake up it does. You can't even eat or bite. That is why i recommend you biting as much as you can when you get them on or...
Your braces WILL hurt. Very few people don't get pain but almost everyone does. You can try taking some pain relief and chew sugar free chewing gum but unfortunately you will have to put up with it....