In many cases of orthodontic treatment the upper anterior teeth are retracted. Periodontal problems may arise during incisor retraction, if the amount of tooth movement and the amount of remodeling in the anterior cortical bone are not the same. Therefore in this study, to find out the relationship between the amount of tooth movement and the amount of bone remodeling during retraction of the upper anterior teeth, lateral cephalograms of 56 female patients over 18-year-old were taken before and after treatment. Among the 56 patients, two groups were divided according to the type of root movement during retraction. 26 patients mainly moved by tipping and 30 by bodily movement. The cephalograms taken before and after treatment were superimposed upon the true horizontal plane. In the Tip-Group, the horizontal bone remodeling/tooth movement ratio was 1 : 1.63, and in the Torque-Group it was 1 : 1.66. Because the amount of tooth movement and the amount of bone remodeling were not the same in both groups, in the Tip-Group the root apex moved away from the palatal cortical plate and closer to the labial cortical plate, whereas in the Torque-Group the root moved away from the labial cortical plate and closer to the palatal cortical plate. Therefore, there are limitations in the amount of incisor retraction in patients with a very thin anterior cortical plate in the maxilla, and in patients with severe skeletal discrepancies orthognathic surgery should be considered and when orthodontic camouflage treatment is the only possible method, the orthodontist must be aware of the limitations of treatment.
Adolescent ; Bone Remodeling* ; Female ; Humans ; Incisor ; Maxilla ; Orthognathic Surgery ; Tooth Movement ; Tooth*

In orthognathic surgery to obtain proper functional and esthetic form after skeletal discrepancy treatment, precise diagnosis and treatment plan are essential. Especially in two jaw surgeries that have serious upper and lower jaw problems, maxilla and mandible are arranged in three dimensions. Based on the maxillary rearrangement, mandibular sagittal and transverse position are determined, and thus new occlusal plane is established. The object of this study is to evaluate the stability of the individual ideal occlusal plane based on the architectural and structural craniofacial analysis of Delaires. The subjects of this study were 48 patients who underwent two jaw surgeries, and they were equally divided into two groups. A and B. A group was operated with ideal occlusal plane and B group was not. Two groups were compared at the preoperative, immediate postoperative (average 4.3days). and long-term postoperative (average 1.3years) lateral cephalometric radiographs. The following results were obtained : 1. ANS was lower than that of PNS for both A and B after the surgery. That is, maxilla and mandible are rotated in posterior and superior direction. 2. Significances were found between T2 and T3 for both a and B are HRP-Me at vertical measurements, articular angle(p<0.01), gonial angle(p< 0.01), and Mn. plane angle(p<0.05) at angular measurement. Mn. plane angle is increased at HRP-Me is decreased for both A and B 3. There is no significance in skeletal stability after the surgery between group A and B. 4. Horizontal movements of B and Pog by surgery have statistically significant inverse correlations with horizontal relapse of B and Pog, and vertical relapse of PNS, as well as Mn. plane angle, and gonial angle after the surgery.
Dental Occlusion* ; Diagnosis ; Humans ; Jaw ; Mandible ; Maxilla ; Orthognathic Surgery* ; Recurrence

Skeletal CI III malocclusion is an orthopedic appliance mainly used for growing children with maxillary undergrowth, which largely entails skeletal CI III malocclusion. It improves anterior crossbite and maxillary position and thus, enables patients to attain favorable profile but often involves unfavorable profile with protrusive upper and lower lips. Therefore, if orthodontists have knowledge of which condition helps obtain favorable occlusion and profile, they are able to predict the prognosis and limitation of the treatment. This study was done in order to help obtain favorable profile after treating growing skeletal CI III children. In the study, we classified children into two groups, the one with favorable profile(Group 1, n=12) and the other with unfavorable profile (Group 2, n=14)and, with retrospective study using pre- and post- treatment lateral cephalogram, drew the following conclusions. 1. As patients had more serious labioversion of upper incisors, they were more unlikely to have favorable profiles after the treatment. Protrusion of prosthion, which was related with maxillary incisors, also affected profiles. 2. As the NL-ML angle before the treatment was small, it was more likely to get favorable profile. 3. As the degree of lower lip protrusion was high, it was likely to have bialveolar protrusion after the treatment. 4. As the degree of downward and backward rotation of mandible was high, it was likely to get unfavorable profile.
Child ; Humans ; Incisor ; Lip ; Malocclusion ; Mandible ; Masks* ; Orthopedics ; Prognosis ; Retrospective Studies*