Oral mucositis score of oral mucosal tissue at different radiation doses. (a) Five different doses (0, 3, 5, 6, and 7 Gy) of radiation were used to establish the model of radiation-induced oral mucositis in minipigs. Experimental animals (n = 3 in each group) that received 6 Gy showed an optimal oral mucositis score (see text for additional details). (b) The weight of the experimental animals was measured every 3 days. In the 7 Gy group, animal weights decreased constantly after receiving irradiation. (c) Photographs of oral mucosal tissues from irradiated minipigs