Abstract
Objective: To investigate the dentoskeletal factors which may predict soft-tissue chin strain during lip closure. Methods: The pretreatment frontal and lateral facial photographs and lateral cephalograms of 209 women (aged 18-30 years) with Angle's Class I or II malocclusion were examined. The subjects were categorized by three examiners into the no-strain and strain groups according to the soft-tissue chin tension or deformation during lip closure. Relationships of the cephalometric measurements with the group classification were analyzed by logistic regression analysis, and a classification and regression tree (CART) model was used to define the predictive variables for the group classification. Results: The lower the value of the overbite depth indicator (ODI) and the higher the values of upper incisor to Nasion-Pogonion (U1-NPog, mm), overjet, and upper incisor to upper lip (U1-upper lip, mm), the more likely was the subject to be classified into the strain group. The CART showed that U1-NPog was the most prominent predictor of soft-tissue chin strain (cut-off value of 14.2 mm), followed by overjet. Conclusions: To minimize strain of the soft-tissue chin, orthodontic treatment should be oriented toward increasing the ODI value while decreasing the U1-NPog, overjet, and U1 upper lip values.
Original language | English |
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Pages (from-to) | 279-287 |
Number of pages | 9 |
Journal | Korean Journal of Orthodontics |
Volume | 43 |
Issue number | 6 |
DOIs | |
Publication status | Published - 2013 Dec |
Externally published | Yes |
Keywords
- Classification and regression tree
- Mentalis
- Soft-tissue chin
ASJC Scopus subject areas
- Orthodontics