By 10-15 years: teeth are worn, and heavy tartar build-up is likely with the possibility of some teeth missing.

10 - 15岁，牙齿磨坏了，严重的牙垢，还有些牙齿都脱落了。

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A removable bridge is best in some cases, particularly if there are a lot of teeth missing.

还有一种活动牙，适合很多病人，特别是缺牙多的病人。

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Where some teeth are missing, dental implants may be used to eliminate the need for a removable Partial denture by providing the support necessary for attachment of a fixed bridge.

在有缺失牙的地方，牙齿种植可以通过固定桥等辅助措施替代局部义齿。

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