Sugar can cause tooth decay by being used as a food source for the bacteria found on our teeth, which causes plaque.

糖通过被那些存在我们牙齿的引起斑块的细菌作为一种食物来源，可以导致牙齿腐烂。

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Deposits of plaque build up between the tooth and the gum.

牙菌斑的沉积物在牙齿和牙龈间形成。

《柯林斯英汉双解大词典》

When not removed, plaque causes tooth decay and gum disease.

牙斑没有清除就会导致蛀牙和牙龈疾病。

《柯林斯英汉双解大词典》

"As soon as the tooth erupts, bacteria start developing plaque, " Nowak says.

CNN: Baby's teeth: What you should know

The conference also heard that good bacteria growing in dental plaque could help fight off bugs that cause gum disease and tooth decay if they are given a competitive edge.

BBC: Dental bacteria swap resistance