CAT and cystic fibrosis: In conclusion, the current study illustrates that the effect of cystic fibrosis-linked systemic oxidative stress and inflammation is extended to the oral cavity, as indicated by the significantly decreased salivary antioxidant enzyme activity levels, including SOD and catalase, and the significantly increased levels of salivary proinflammatory cytokine levels, including TNF-α and IL-6, in our CF children.