Three-dimensional analysis of the positional relationship between the dentition and basal bone region in patients with skeletal Class I and Class II malocclusion with mandibular retrusion.

Mandibular anterior teeth in Class II malocclusion exhibit a compensatory labial inclination trend with the crown and apex relative to the basal bone region when mandibular retrusion occurs. Moreover, as the root apices of the maxillary anterior teeth are much closer to the labial side in Class I and Class II malocclusion, the range of movement at the root apex should be limited to avoid extensive labial movement.