A.牙列缺失 B.楔狀缺損 C.四環(huán)素牙 D.氟斑牙 E.遺傳因素
A.40% B.91.20% C.29.4% D.1/4 E.1/3
A.40% B.29.4% C.25% D.91.20% E.48.87%