Before undergoing radiotherapy, your dentist may recommend that you wear radiation mouth guards during your treatment. When radiation hits metal in a person’s mouth, the radiation scatters and may be associated with an increased risk for developing mouth sores. Thus, it is often recommended that patients wear custom radiation mouth guards when undergoing radiation if the metal in their mouth will be in the field of the radiation. The mouth guards do not eliminate the risk of developing mouth sores, but may help reduce the risk by preventing the soft tissue from directly touching the intraoral metal. Nonetheless, radiation mouth guards are not always indicated. They are recommended depending on the amount of metal fillings you have in your mouth, the dosage of radiation that you will receive and the location of the radiation.