• The korean journal of orthodontics
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• v.37 no.4
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• pp.272-282
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• 2007

The purposes of this study were to evaluate the nasolabial angle changes between closed lip position at centric occlusion and relaxed lip position at which the bite is open so that the lips do not touch and to elucidate the significance of the relaxed lip position for dentofacial diagnosis. Methods: The subjects consisted of 60 (35 Males, 25 Females) skeletal Class III malocclusion adult patients (mean age 23.3 years) with anterior crossbite. Results: In Class III malocclusion adult patients, there were significant differences in the nasolabial angle changes between closed lip position and relaxed lip position. Using the cluster analysis, the subjects were divided into three groups according to the pattern of nasolabial angle change: Group 1 (N = 27, 45%, $-8\;{\sim}\;1$), Group 2 (N = 30, 50%, $2^{\circ}\;{\sim}\;17$), and Group 3 (N = 3, 5%, over 18). Conclusion: The results showed that the pattern of the nasolabial angle change between closed lip position and relaxed lip position varies in skeletal Class III malocclusion patients. Thus, relaxed lip position should be taken into account when diagnostic records are obtained and analyzed to accurately to evaluate the facial soft tissues and predict facial esthetics after surgical-orthodontic treatment.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.7 no.1
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• pp.19-26
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• 1977

The purpose of this study was to obtain the cephalometric maxillofacial soft tissue measurements, and to define the differences that exist between males and females on the soft tissue profile who had normal occlusion in mixed dentitions. For the object of this study, cephalometric radiographs were obtained from the centric occlusion with the relaxed lip position. Copper filter was designed to obtain both hard and soft tissue structure on the same film. The subjects consist of 100 males and 100 females from 8 to 12.4 years with the normal occlusion and acceptable profiles. The author measured facial depth, vertical height from the tissue profiles in the mixed dentitions. The significant test compare males with females. The following results were obtained from the study 1. In facial convexity, much more larger females than that of males. 2. Inclination of the lip posture were more larger in maxilla (male) and in females more larger in the mandible. 3. The thickness of soft tissue were thicker in males, the height of nose were more prominent in females. 4. There were no significant differences in both sexes.