Invisalign is a great alternative to traditional metal braces, especially for adults who do not want to be embarrassed by braces in the workplace. Invisalign is a type of orthodontic treatment that consists of a series of clear custom-made retainers that move teeth. Each retainer in the series moves a select group of teeth a small amount, before the patient moves on to the next retainer. If you prefer to stay away from braces, this is one of the better options.