牙周炎 Traditional form: 牙周炎 Pinyin (reading): yázhōuyán Definitions: periodontitis (gum disorder) Characters: 牙 - tooth, molar; fang, tusk; serrated 周 - Zhou dynasty; circumference 炎 - flame, blaze; hot Traditional characters: 牙 - tooth, molar; fang, tusk; serrated 周 - Zhou dynasty; circumference 炎 - flame, blaze; hot