Main Instructor Chien-Wei Chao
Department / Institution Orthodontic Department, Chung Shan Medical University Hospital
Classification Case report
This case report is to compare the different type treatments of anterior cross bite in mixed dentition.
Case 1 was an 8 year-old boy in early mixed dentition. Data collections found flush terminal plane with class II pattern, the 11, 21, 22 were shown cross bite with spacing of lower anterior teeth, low tongue posture with tongue tie, and orthognathic face. The treatment plan was by myofunctional therapy, using Myobrace (i3) appliance combined with tongue tie release surgery. After this the patient was followed with 2X4 fixed appliance therapy.
Case 2 was a 10 year-old boy with meiodens in late mixed dentition. Oral examination showed Angle class I malocclusion, anterior cross bite with 22 blocked in, and skeletal class III tendency. The treatment plan was removing mesiondens, using anterior inclined plane for 1 month and followed with full mouth fixed brass appliance.
「Discussion and Summary」
Two etiologies of anterior cross bite can be the permanent tooth buds are trapped lingually or overretatined primary tooth in mixed dentition. The soft tissue origin anterior crossbite etiology can be caused by patient’s low tongue posture. The dentition can be found with anterior spacing.
Orthodontic treatment performed in early mixed dentition may be from the following reasons: First, the lingually positioned maxillary incisors limit lateral jaw movements and these teeth will sustain incisal abrasion. Second, the high risk of gingival recession for the incisors.
In present cases, we found two different types of anterior cross bite. Case I was low tongue posture problem, treated with myofunctional therapy and 2X4 fixed orthodontic appliance. Case 2 was combined with dental and skeletal problem. He was treated with anterior inclined plane and full mouth fixed orthodontic appliance. All these two cases, the final treatment outcome showed angle class I molar and normal anterior overbite and overjet.
In conclusion, differential malocclusion diagnosis combined with a correct orthodontic appliance can help in the orthodontic treatment.
Anterior Crossbite Treatment in Early or Late Mixed Dentition Treatment