Methods: a rubber dam was placed over the teeth to protect the gum.
2
日本福冈九州大学的研究人员提出,抗氧化剂——儿茶素可以起到保护牙龈的作用。
Researchers from Kyushu University in Fukuoka, Japan suggest that the antioxidant catechins may be responsible for the protective effects.
3
牙膏并不清洁牙齿,他们只是含有特殊物质预防龋坏,控制菌斑,增白,保护牙龈或者保护改善牙齿过敏。
Toothpastes don't just clean teeth anymore. They have special ingredients for preventing decay, plaque control, tartar control, whitening, gum care or helping sensitive teeth.