Abstract
The occlusal plane is normally evaluated for occlusal reconstruction in prosthetic treatment. It has a major effect on the anteroposterior position of the mandible and mandibular opening and is an important factor in deciding the skeletal pattern. The upper occlusal plane（ UOP） is a reference plane used for occlusal reconstruction and its evaluation and diagnosis are key points in prosthodontic therapy. The patient with high angle class II open bite presented with a v-shaped occlusal plane（ consisting of a flat maxillary anterior occlusal plane and steep maxillary posterior occlusal plane） and a steep mandibular plane. The deficiency of the occlusal vertical dimension in the molars caused the mandible to be rotated in a posterior direction（ rotated clockwise and expanded）， resulting in open bite. In such patients， active occlusal plane reconstruction and anterior repositioning of the retruded mandible are important. The therapeutic steps taken in this patient are described here.
