Reliability of a Method for Computing Facial Symmetry Plane and Degree of Asymmetry Based on 3D-data

Abstract

This method can be used to compute with high reliability the symmetry planes and degree of asymmetry of facial 3D-data. The color-coded visualization of asymmetrical facial regions makes it possible for this analytical procedure to capture the asymmetries of facial soft tissue with substantially greater precision than 2-dimensional en face images.

3D Soft Tissue Analysis – Part 1: Sagittal Parameters

“…For instance, various 3D techniques have been used for analyzing the facial soft tissue involving the determination of landmarks and by measuring angles, distances, surfaces and volumes [9,23,30,38,43]. In 2007 Hartmann et al [13] reported on a facial symmetry plane for determining the degree of asymmetry in orthodontic patients. A similar method was applied in 2008 by Stauber et al [44] as well for assessing facial symmetry in patients with cleft lip and palate.…”

Three-dimensional evaluation of facial asymmetry in association with unilateral functional crossbite in the primary, early, and late mixed dentition phases

“…3,[22][23][24][25] In the present study a landmark independent method, which has been previously reported to be a more accurate method for assessing asymmetry, 26 was used. It has been previously reported that subjects with unilateral functional CB already exhibit greater facial asymmetry in the primary dentition phase than do subjects without CB.…”

Alternatives to Radiation Investigations in Orthodontics

“…This is an advantage of the scans because repositioning the live patient can be difficult and sometimes embarrassing. The accuracy and repeatability of 3D Imaging has been documented as exceptional 96 and, as with most recordings, in order to eliminate inter-operator variability all measurements should be made by the same investigator. The angular measurements are dependent on head position and need to be standardized across the sample 55 .…”

“…It is becoming a vital tool in orthognathic surgery planning, patient education, "teleorthodontics" 7 to manage global movement of patients, and where interdisciplinary treatments are sought. It is an effective recording method for various facial asymmetries 96 and severe craniofacial dysostoses, hemifacial microsomias 101 , and where simple photographs have serious limitations. The non-invasive nature of 3-D imaging will make its application widely accepted for sequential evaluation in growing children and on controls for research 96 .…”

“…It is an effective recording method for various facial asymmetries 96 and severe craniofacial dysostoses, hemifacial microsomias 101 , and where simple photographs have serious limitations. The non-invasive nature of 3-D imaging will make its application widely accepted for sequential evaluation in growing children and on controls for research 96 . However, the idea of obviating lateral cephalograms entirely may not yet be the case because radiographs still provide valuable skeletal and dental information vital for initial treatment planning.…”