I too had braces. It did not hurt at all to have them removed. In fact, I really enjoyed getting them off. My teeth were a bit sore when chewing for a day or two, but it was nothing more than mild discomfort. Your dentist or orthodontist will decide what type of retainer you need. It is important to wear them as instructed. After a few months, I did not continue to wear my bottom retainer and my teeth slid back out of place. Most of the time, you will be given a top and bottom retainer to wear when you are sleeping. These retainers can be removed and sometimes you even get to pick the color. Occasionally, a dentist may want to use a permanent retainer. This kind stays in place all the time. It will really just depend on your personal medical needs.