A Bonded Lingual Retainer is usually comprised of a braided stainless steel wire that connects to the lingual (back) surfaces of the front teeth. The Bonded Retainer is used to maintain a previous orthodontic result or to simply prevent undesirable movement of the teeth.
One of the benefits of getting a bonded retainer is that it will help hold your teeth straight. However, bonded retainers do NOT serve as a substitute for clear removable retainers and alone will not guarantee teeth to remain straight. For that reason, you will still be expected to wear a clear removable retainer over the top of your bonded retainer.