Chin and Lip Esthetic Changes Analysis in Class Ⅱ Division 2 Malocclusion of Adults Treated by Non-extraction Protocol

Abstract

Abstract: Objective: To investigate the soft and hard tissue esthetic changes of the chin and lip in Class Ⅱ division 2 malocclusion of adults treated by non-extraction. Methods: Twenty adult patients were enrolled and orthodontically treated without extraction. The radiographs were processed using CASSOS Image software. The data was analysed statistically to compare the soft and hard tissue esthetic changes of the chin and lip before and after the treatment. Results: After the treatment, the angles of U1-SN,L1-MP, and the distance of U1-AP,U1-NA, L1-AP,L1-NB were greater than those in pre-treatment. Meanwhile, U1-L1 decreased. Crowns of incisors were compensatorily moved close to labial side so as to acquire proper overbite and overjet. The distance of LLP,EP-LL increased obviously, and the lower lip was moved labially. Conclusion: Patients can not only relieve atresia relationship of anterior teeth but also improve the esthetic curve of chin and lip by protrusion of lower lip after non-extraction treatment.

Key words: Class Ⅱ division 2 malocclusion, Cephalometric analysis, Non-extraction, Chin and lip

CLC Number:

R783.5

WEI Jia-dai, LIU Jian-ying, MO Shui-xue. Chin and Lip Esthetic Changes Analysis in Class Ⅱ Division 2 Malocclusion of Adults Treated by Non-extraction Protocol[J]. Journal of Oral Science Research, 2015, 31(7): 695-698.

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