Other types of retainers are Hawley retainers. These retainers are not quite so sensitive and can be cleaned with a toothbrush and toothpaste. The thick acrylic palate can absorb liquid/saliva so cleaning these regularly is very important. No one likes an old smelly retainer!
Permanent retainers are a bit different with cleaning because they are affixed to your teeth. This then falls under your proper oral hygiene routine. To keep the fixed wire clean you must floss with a floss threader around the retainer. Another alternative is to use a WaterPik.
It is important to keep retainer clean and in their case when not in use. With these simple instructions, and discipline to wear them, you can feel confident that you will have a clean retainer and straight teeth for the rest of your life!