A.5mm B.10mm C.15mm D.20mm E.6mm
A.<10mm B.>14mm C.5~10mm D.10~14mm E.15~18mm
A.左前斜位,冠狀面與暗盒成40~45° B.右前斜位,冠狀面與暗盒成45~55° C.胸正位——冠狀面平行暗盒 D.胸側(cè)位——冠狀面垂直暗盒 E.前凸位——胸部冠狀面與暗盒不小于45°