[The importance of variability in morphologic feature of upper central incisors in linguoversion anterior deep over bite].

190 subjects with linguoversioffl anterior deep over bite, labioversional anterior deep over bite, normal occlusion and anterior cross-bite were chosen for cephalometric analysis. The findings are that most of the upper central incisors in linguoversional anterior deep over bite exist crown-root angulation in a labiolingual direction. This may be one of the causing factors to induce and promote the anterior deep over bite. So that the crown-axis and root-axis of the upper central incisors should be traced separately in cephalometric analysis of linguoversional anterior deep over bite.