Invisalign (a.k.a. invisible braces) differs from traditional braces in that it does not involve any metal brackets or wires. Invisalign is a series of clear, removable teeth aligners that patient wears over a period of time 22 hours a day or more. They have become quite popular among adult patients because they are viewed as more acceptable in appearance than having metal wire in the mouth. However, the mechanics of invisalign are quite different than traditional wires and brackets in that some movement of teeth cannot be achieved with this type of treatment. Case selection is very important. Not everyone is a candidate for it.