I have been using nightguards for bruxism for 10 years and had no idea that they held on to a huge amount of gunk from saliva and bacteria that builds up overnight. I saw a commercial on IG saying that the bacteria can cause illness. I received this product quickly after ordering it online. It works by using a sanitizing light and vibration to shake the bacteria off. It's so gross to see the amount of gook that comes off the guard after one night. You're supposed to change guards every 2-3 years, and without proper cleaning, it will hold on to a lot of germs. Very glad I purchased this product, I can tell that my occlusal guard is much cleaner now, and will likely last longer.