A.0.1mm B.0.15~0.38mm C.0.4mm D.3~4mm E.1~2mm
A.牙釉質(zhì)和牙骨質(zhì)端端相接占10% B.牙釉質(zhì)覆蓋牙骨質(zhì)少許占30% C.牙釉質(zhì)覆蓋牙骨質(zhì)少許占60% D.牙骨質(zhì)覆蓋牙釉質(zhì)少許占60% E.牙釉質(zhì)和牙骨質(zhì)分離占30%
A.無哈佛管 B.無血管 C.無神經(jīng) D.無細(xì)胞 E.有穿通纖維