Over-whitening can also cause teeth to become thin and brittle and can lead to high sensitivity and discoloration as tooth enamel becomes translucent.

美白牙齿过度，会使牙齿变得薄弱。同时，由于牙釉质变为半透明状，会导致牙齿高度敏感、变色。

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Root canal treatment and finished tooth, lost in the pulp cavity nutrition supplies such as nerves, blood vessels, lymphatic, makes itself become more brittle fracture of teeth.

且做完根管治疗的牙齿，失去了牙髓腔中神经、血管、淋巴等营养供应，使得牙齿本身变得较脆易断裂。

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