Anterior open bite is one of the most difficult dentofacial deformities to be treated in orthodontic field. In traditional classification, open bites can be divided into two categories: skeletal and dento-alveolar. However, what we are frequently dealing with in our clinic practice are the following two special types of anterior open bite: one is skeletal open bite; the other is open bite combined with incisor proclination, which is included in dento-alveolar abnormalities. If the former, it should be the result of deficiency of mandibular ramus as well as backward inclination of the mandible, therefore it shows an increased angle between mandibular body and ramus. If the latter, the mainly reason goes to the excessive proclination of both maxillary and mandibular incisors, so the patient may show up with convex profile but normal mandibular anatomical conformation. In this case, the main problem is the sagittal abnormality in spite of vertical contact deficiency between anterior teeth. We have explored the treatment design and orthodontic mechanics control of the above types of open bite with lingual orthodontic system. Due to the particularity of lingual system mechanics, torque loss might be a common side effect of conventional lingual system. So we choose customized lingual system with vertical slots for the anterior teeth and take advantage of ribbon-wise archwires at the same time to prevent torque loss. We also are going to compare the biomechanics between lingual and labial orthodontic system in anterior open bite treatment as biomechanics for lingual orthodontic system are quite different from labial one. Besides, the implant anchorage is used to assist vertical and sagittal controlling to achieve optimum facial results in some difficult cases, and we are going to demonstrate the comparison of implant anchorage biomechanics in lingual and labial orthodontic systems.
Recognize the classification of anterior open bite.
Distinguish the biomechanics between labial and lingual orthodontic system in the treatment of anterior open bite.
Determine the treatment design in the treatment of anterior open bite via both labial and lingual orthodontic system.