You are allowed to take impressions for both whitening trays and mouth guards. However, you must use only whitening materials that are generally available to the public without a prescription.Furthermore, if you are operating in the public domain (outside of a dental office), it may be inappropriate for you to advertise that you are a CDA II, as it may suggest to the public that you are offering a service supervised by a dentist. It may also convey that your service is sanctioned by the ODAA.