Hi J:Sorry this reply is late in coming - there have been lots of things going on in the Zellies world! I appreciate your question - and suggest asking your dentist - since he should know more about the actual material from which your retainer has been made. Generally I suggest cleaning a retainer with a brush and toothpaste to clean away pieces of food etc.
I think denture cleaning products help to keep the item clean - but check with your dentist because some plastics are more sensitive than others.
The main thing is to rinse any solutions off your retainer in clean running water. Then the last rinse on your teeth at night will be the ACT.
Wearing the retainer immediately after spitting out this rinse will ensure that a tiny residue of ACT will remain on your teeth to protect them during the night. If you drink during the night - I suggest you add a half teaspoon of xylitol into the water - an extra measure of protection!
Hope this helps,
Ellie Ellie Phillips DDS www.ZelliesCleanWhiteTeeth.com Solutions for Oral Health! author, Kiss Your Dentist Goodbye