A.9~10mm B.7~8mm C.5~6mm D.3~4mm E.1~2mm
A.>1.0mm B.0.75~1.0mm C.0.5~0.75mm D.0.25~0.5mm E.<0.25mm
A.與齦緣接觸 B.離開11~15mm C.離開6~10mm D.離開4~6mm E.離開1~3mm