Retainers are a longer-term solution for maintaining newly straightened teeth by ensuring they don't move back. Braceline Centre offers clear retainers, permanent retainers and traditional metal retainers. Clear retainers are clear, removable custom fit retainers. Permanent retainers are glued to the back of your teeth and are not visible. Traditional metal retainers are durable, adjustable, and removable. They can be active to slightly move teeth or inactive to hold teeth in their current position.