1.Correlation between menton deviation and dental compensation in facial asymmetry using cone-beam CT.
Soo Byung PARK ; Jeong Heuy PARK ; Yun Hoa JUNG ; Bong Hye JO ; Yong Il KIM
Korean Journal of Orthodontics 2009;39(5):300-309
OBJECTIVE: The purpose of this study was to evaluate the correlation between menton deviation and dental compensation in facial asymmetry. METHODS: Tooth axis and distance of first molar and canine to the reference plane were investigated by cone-beam computerized tomography. The subjects consisted of 50 patients with asymmetric mandibles (male 21, female 29, mean age 24.3 years). Control groups were also assessed (male 11, female 9, mean age 25.6 years). Nine measurements (5 linear measurements and 4 angular measurements) were measured in order to evaluate the correlation between menton deviation and the linear and angular difference of first molar and canine in the deviated and none-deviated sides using the defined MPR images. The differences between deviated and non-deviated side, according to menton deviation, were statistically analyzed using stepwise multiple regression analysis. RESULTS: From the result, Menton deviation was negatively correlated with mandibular first molar's angular measurement (Delta Angle LM6-Mn plane (dev.-ndev.)) and positively with maxillary fist molar's angular measurement (Delta Angle UM6-FH plane (dev.-ndev.)) (p<0.01). Two angular measurements (Delta Angle LM6-Mn plane (dev.-ndev.), Delta Angle UM6-FH plane (dev.-ndev.)) explained the variability in menton deviation with a significant r2 value of 0.589. CONCLUSIONS: This study suggests that the tooth axis of upper and lower first molars leans towards the deviated side of Menton when there is mandibular asymmetry with Menton deviation.
Axis, Cervical Vertebra
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Compensation and Redress
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Cone-Beam Computed Tomography
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Dental Occlusion
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Facial Asymmetry
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Female
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Humans
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Mandible
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Molar
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Tooth