Objective: To explore the change rules and corresponding biomechanical mechanisms of labiolingual inclination during mandibular anterior teeth intrusion with clear aligners and to obtain accurate labiolingual directions control strategies for vertical intrusion of the teeth. Method: A finite element model of vertical intrusion of the mandibular anterior teeth with clear aligners was established. The incisor mandibular plane angle (IMPA) of different mandibular anterior teeth were designed. The conventional group, labial attachments group, labial power ridge group and lingual power ridge group were set separately to analyze movement trends and labiolingual torque of the mandibular anterior teeth. Results: When the IMPA was <90°, the crowns underwent lingual torque during intrusion of the mandibular anterior teeth. When the IMPA was >90°, the crowns underwent labial torque. Adding a labial power ridge to the crowns of the mandibular anterior teeth resisted the coronal-lingual torque trend, whereas adding a lingual power ridge and labial attachments to the crowns of mandibular anterior teeth increased the coronal-lingual torque trend. Conclusions: During the process of the mandibular anterior tooth intrusion with the transparent appliance, the crown of the tooth may present an undesigned labiolingual movement. When the crown is tilted towards the labial side, the lingual power ridge can be designed to avoid the crown moving to the labial side. When the crown is tilted towards the side of the tongue, the labial power ridge can be designed to avoid the crown moving to the lingual side.