Comparsion of soft and hard tissue profiles of adolescent patients with class II division 1 malocclusion between before and after treated with two different kinds of tooth extraction methods / 吉林大学学报(医学版)

Objective: To compare the changes of soft and hard tissue profiles of the adolescent patients with class II division 1 malocclusion between before and after treated with two different kinds of tooth extraction methods, and to provide the reference for clinical treatment. Methods: A total of 60 adolescent patients with class II division 1 malocclusion were included, and they were divided into 44/44 group (n=30) and 44/55 group (n= 30) based on different kinds of tooth extraction methods. Four first premolars of the patients in 44/44 group were extracted and 2 maxillary first premolars and 2 mandibular second premolars of the patients in 44/55 group were extracted. The measurement indexes of pre-treatment (Tl) and post-treatment (T2) and their difference values (T2 -Tl) of soft and hard tissues of the adolescent patients were detected by lateral cephalometric radiographs. Results: As for the hard tissue, compared with before treatment, the Overjet, SNA, ANB, Ul-NA, distance of Ul-NA, Ul-SN, NA-PA, and A-NP of the adolescent patients in two groups after treatment were decreasd (P0. 05). Conclusion: The changes of soft and hard tissue profiles of the adolescent patients after treated with two different kinds of tooth extraction methods are not significant.

Changes of soft and hard tissues of patients with Angle classⅡdivision I malocclusion following orthodontic treatment with extraction / 天津医药

Objective To investigate changes in craniomaxillofacial soft and hard tissues following orthodontic treatment by MBT edgewise technique with fix appliance in patients with Angle classⅡdivisionⅠmalocclusion. Methods Fifty patients with Angle classⅡdivisionⅠmalocclusion were selected in this study. All patients were treated with MBT edgewise technique. Cephalometrics tracings were performed before treatment and after treatment. Cephalometrics measurements were statistically analysed by t-test. Results After the orthodontic treatment, the main changes were the reduction of maxillary and mandibular prominence and the increasement of the Pg′B′-FH and Pog-Pog′and upper-lower prominence as well. The appearance of uncovered teeth by their lips was obviously improved. The changes of soft issue profile are the increment of nasolabial angle and the changes among UL-U1, LL-L1 and the E-line. Conclusion Patients with Angle classⅡdivisionⅠmalocclusion have normal overjet and overbite, and also have a better appearance of soft tissue after the extraction treatment.