An adult case of skeletal open bite with a large lower anterior facial height.

Control of the height of posterior dentoalveolar regions is of great importance for the correction of skeletal open bite. Traditionally, second premolar extraction facilitates the closure of open bite by inducing a counterclockwise mandibular rotation without molar intrusion. This article reports treatment for a 24-year six-month-old female patient with an open bite and large anterior facial height. She complained of occlusal disturbances and difficulty of lip closure because of the open bite. Overjet and overbite were +3.0 mm and -3.0 mm, respectively. To correct open bite and crowding, the bilateral extraction of the maxillary and mandibular second premolars plus multibracket appliances for mesial movement of the molars was selected as the treatment plan. After a two-year treatment, an acceptable occlusion was achieved, the lower anterior facial height was decreased, and the lips showed less tension in a lip closure. An acceptable occlusion was maintained without recurrence of the open bite during a three-year retention period, indicating a long-term stability of the occlusion. The results of this treatment indicated that the correction of open bite with no or less molar intrusion or incisor extrusion is of great importance for achieving stable occlusion and avoiding the relapse of open bite.