
My retainer has been dirty for a long while. How can I clean it?
Consult your dentist that gave you the retainer. Since you went so long with out wearing it, it may now not fit correctly. You also stated that it was made out of plastic. Plastic is porous so it retains dirt and stains. Using products that are not designed for retainers may not be a good idea either. Since a retainer is something you put in your mouth play it safe and get a new one.