A. Dear Louise, Invisalign Teen has been specifically designed for teenagers, so that they can enjoy normal teen life. Invisalign Teen is a series of removable aligners that you wear for about 20 hours each day. The aligners are made from lightweight plastic and every two weeks you move to the next aligner in the series. Each aligner is slightly different, moving your teeth gently into the desired position. If your brother has erupting or erupted permanent dentition, he may be suitable for this treatment. An Invisalign dentist will be able to advise you further. If for whatever reason he is not suitable for Invisalign, than you may wish to consider the option of high tech fixed braces, which are also speedy and comfortable. Kind regards, Sunita