How should dental retainers be cleaned?

Q: My son, 10 years old, has a new dental retainer and says that even after cleaning it, it has an odour to it. Can the retainer be placed in a mouthwash and for how long?

A:Clean the retainer with soap and water then it should not have any odour. Still if your feel that it is not enough then soak in mouth wash for 5 minutes to kill the odour.