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    ABSTRACT: The natural head position in standing subjects was studied on cephalometric profile radiographs of 120 Danish male students aged 22-30 years. Two head positions were recorded, one determined by the subjects own feeling of a natural head balance (the self balance position) and the other by the subject looking straight into a mirror (the mirror position). The reproducibility of the two head positions was assessed. The reference points were recorded by the D-Mac Pencilfollower on punched cards, and a computerized technique was developed for transfer of reference points between the two series of films. It was found that in the mirror position the head was kept higher than in the self balance position. The variability in inclination of the craniofacial and cervical reference lines to the true vertical and to each other in the two head positions was reported. Analysis of the pattern of associations within the craniocervical complex was suggested to clarify the relationship between head balance and facial morphology.
    Acta Odontologica Scandinavica 12/1971; 29(5):591-607. DOI:10.3109/00016357109026337 · 1.31 Impact Factor
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    ABSTRACT: Developments in computer technology have made the 3-dimensional (3D) diagnosis of facial soft tissues possible, opening the window for 3D soft-tissue evaluation in orthodontic treatment planning and posttreatment results. Korean adults (30 men, 30 women) with normal occlusion were scanned with a 3D laser scanner, and 3D facial images were made with the Rapidform 2004 program (Inus Technology, Seoul, Korea). Reference planes in the facial soft tissues of the 3D image were established, and a 3D coordinate system (X-axis, left/right; Y-axis, superior/inferior; Z-axis, anterior/posterior) was established; 29 measurement points were assigned on the 3D image, and 39 linear measurements, 8 angular measurements, and 29 linear distance ratios were obtained. Significant differences between the sexes were found in nasofrontal angle (men, 142 degrees; women, 147 degrees) and transverse nasal prominence (men, 112 degrees; women, 116 degrees) (P <.05). Transverse upper lip prominence was 107 degrees in the men and 106 degrees in the women, and transverse mandibular prominence was 76 degrees in both sexes. The distance between lower lip vermilion border (Li) and Me' was 0.4 times mandibular body length (Me' - Go'), and mouth height was also 0.4 times the mouth width. The linear distance ratios from the coronal reference plane to fronto-temporal point, zygomatic point, pronasale, upper lip point, labrale inferior, and soft-tissue menton were -1, -1, 1, 0.5, 0.5, and -0.6, respectively. These data could be guidelines for the 3D evaluation of the facial image, because the 3D facial model constructed by the averaged coordinate values could be a template for orthodontic diagnosis and treatment planning.
    American journal of orthodontics and dentofacial orthopedics: official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics 06/2007; 131(6):759-66. DOI:10.1016/j.ajodo.2005.08.038 · 1.44 Impact Factor
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    ABSTRACT: Laser scanners are becoming increasingly important as a tool for quantifying the outcome of facial surgery. However, few computer algorithms have been developed for this purpose. Researchers have either measured the differences in the positions of (manually located) landmarks, or have taken radial measurements of the distances between surfaces. Neither of these techniques provides satisfactory information about the shape changes between surfaces. In this paper, alternative methods are proposed and their performance is compared with that of the radial method. Tests on two patients show that the Correspondences by Sensitivity to Movement (CSM) and closest point algorithms provide the most realistic measurements of the differences between two surfaces. The CSM method was found to be useful for pinpointing areas where the shape has changed.
    International Journal of Oral and Maxillofacial Surgery 01/2002; 30(6):484-9. DOI:10.1054/ijom.2001.0173 · 1.36 Impact Factor