The demineralization of cementum and dentin can occur in a pH range of 6.2-6.8.

牙骨质和牙本质脱矿可以在pH6.2到6。8的范围内发生。

The root is covered by cementum, which is a bonelike substance that the periodontal ligament's fibers attach to.

包裹着牙根的是牙骨质，是一种骨样物质，也是牙周韧带纤维连接的部分。

If the gingiva recedes or plaque forms between the gingiva and the root, bacteria and acids have direct access to the cementum, which is much softer than enamel and dissolves more quickly.

如果牙龈退缩或牙龈和牙根间形成牙斑，细菌和酸就可以直接侵犯牙骨质，与牙釉质相比牙骨质更软，溶解更快。

Dental caries lesions typically form in an environment where there are lots of sugars in the mouth and a pH below 5.5 for enamel and below 6.2 to 6.8 for cementum and dentin.

龋齿一般发生在口腔中多糖、牙釉质pH低于5.5、牙骨质和牙本质pH处于6.2到6。8的情况下。