After braces are removed, retainers are necessary  for both upper and lower jaw.Type of retainer and duration varies case to case.Your attending orthodontist would decide on that. But retainers are must to prevent prolapse.

Hello Mostly retainers are put for both upper and lower teeth..to prevent the relapse of teeth to their previous position.. And generally, the duration of retainers equals the duration of orthodontic treatment. If in doubt, just visit your Orthodontist and get all the doubts cleared.

Hello Mam Dr Vasundhara here, Orthodontist (braces specialist) practicing in Bangalore. Choice of retainer depends on your pre treatment malocclusion. This means how malaligned your teeth were before treatment. Also there are types of retainers. Generally retainers are required and are must after your braces treatment is finished. You can get detailed idea in an offline consultation regarding your query.