Mandible deformed and mandibular body bended downwards under the chincup forces; and the larger the forces were,the severer the deformation was.

• 颏兜牵引力使下颌骨顺时针向旋转的同时将使下颌骨发生变形:下颌枝向前弯曲,下颌体向下弯曲,且牵引力越大旋转、变形越严重。