In orthodontics, a ligature is the small elastic band that is used to affix the archwire to the bracket. Ligatures are usually changed at each adjustment, and come in many varied colors including transparent. A series of ligatures connected to each other and used to pull teeth together with more strength is called a powerchain. Ligatures can also be made of wire.
Self ligation is a bracket that has a sliding or rotating mechanism to ligate an archwire. This type of bracket replaces elastic ligatures that are traditionally used. Self ligation typically cuts orthodontic appointment time drastically. Currently, self ligating brackets make up about 10 percent of total bracket sales worldwide.