A.1~2mm B.3~4mm C.5~6mm D.7~8mm E.9~10mm
A.與黏膜密合 B.離開黏摸0.5~1.0mm C.離開黏摸1.5~2.0mm D.離開黏摸2~2.mm E.離開黏摸3~4mm
A.0.5mm B.1.0mm C.1.5~2mm D.2.0mm E.2.5mm