Predictors of favorable soft tissue profile outcomes following Class II Twin-block treatment
10.4041/kjod.2018.48.1.11
- Author:
Ji Eun KIM
1
;
Su Jung MAH
;
Tae Woo KIM
;
Su Jung KIM
;
Ki Ho PARK
;
Yoon Goo KANG
Author Information
1. Department of Orthodontics, College of Dentistry, Kyung Hee University, Seoul, Korea. deodor94@khu.ac.kr
- Publication Type:Original Article
- From:The Korean Journal of Orthodontics
2018;48(1):11-22
- CountryRepublic of Korea
- Language:English
-
Abstract:
OBJECTIVE:The aim of this study was to determine cephalometric factors that help predict favorable soft-tissue profile outcomes following treatment with the Class II Twin-block appliance.
METHODS:Pre- and post-treatment lateral cephalograms of 45 patients treated with the Class II Twin-block appliance were retrospectively analyzed. Profile silhouettes were drawn from the cephalograms and evaluated by three orthodontists in order to determine the extent of improvement. Samples were divided into a favorable group (upper 30% of visual analogue scale [VAS] scores, n = 14) and an unfavorable group (lower 30% of VAS scores, n = 14). Skeletal and soft-tissue measurements were performed on the cephalograms and an intergroup comparison was conducted.
RESULTS:An independent t-test revealed that the following pre-treatment values were lower in the favorable group compared to the unfavorable group: lower incisor to mandibular plane angle, lower incisor to pogonion distance, point A-nasion-point B angle, sella-nasion line (SN) to maxillary plane angle, SN to mandibular plane angle, gonial angle, and symphysis inclination. The favorable group had a larger incisor inclination to occlusal plane. Moreover, the favorable group showed larger post-treatment changes in gonial angle, B point projection, and pogonion projection than did the unfavorable group.
CONCLUSIONS:Class II malocclusion patients with a low divergent skeletal pattern and reduced lower incisor protrusions are likely to show more improvement in soft-tissue profile outcomes following Class II Twin-block treatment.
