distal surface meaning in English

远极面
远中面

Ru1ls : the root surface with high root caries prevalence rate are labial surfaces of incisor and canine , mandibular premolar and molar , lingual surfaces of mandibular incisor and canine and maxillary molar , distal surface of premolar and mesial surface of molar
结果：根面龋易感性高的根面为前牙、下领前磨牙、磨牙的唇（颊）面、下前牙与上领磨牙的舌面、前磨牙的远中面、磨牙的近中面。