Inclusion Criteria:  Karnofsky Performance Score (KPS) >/= 60% life expectancy > 9 months histologically proven malignant disease of the head and neck region lntensity Modulated RadiationTherapy (IMRT) radiotherapy Minimal Dose to the oral mucosa >/= 30 Gy (EQD2 w. a/ß 2) Simultaneous use of mouthwashes is allowed if previously prescribed by the treating physician  Exclusion Criteria:  history of Severe oral Mucositis (SOM) due to chemotherapy within the last 3 months previous radiotherapy in the head-neck region previous cryotherapy within the last 6 weeks Minimal doses </=30 Gy (EQD2 w. a/ß 2) known history of ethylene-vinyl acetate allergy Simultaneous use of other forms of oral cryotherapy