Comparison of perceptions of computer-animated left- and right-facing profiles.
OBJECTIVE
Although scientific publications differ in displaying left- or right-facing profiles, there are few systematic studies of the possible effects of directional biases and laterality on patients' and clinicians' perceptions of treatment need, outcomes, and satisfaction. As part of a research program to quantitate the physical bases of the perceived zone of acceptability and most-pleasing facial profiles, responses to computer-animated left- and right-facing soft-tissue profile images were compared and related to eye and hand preference.


METHODS
Standardized left-facing, soft-tissue profile images were captured in color and digitized. The right-facing profile was created by reversing the left profile image to display a mirror image. Using imaging and customized morphing software, retrusive and protrusive extremes were created, from which transitional frames were developed to display five features of the soft-tissue profile: upper lip, chin, bimaxillary position, lower face height, and mandible. One left- and one right-facing profile for a Class II division 1 female, and Class III male were randomly presented to 24 subjects who were asked to indicate: 1) acceptability by pressing a mouse button and releasing the button when the images were no longer acceptable; and 2) most-pleasing image by pressing the mouse button once.


RESULTS
No differences were found between left- and right-profile images for zone of acceptability, midpoint of the zone of acceptability, or most pleasing; nor was there any relation to laterality measures. However, consistently higher intercorrelations among the features for the zone of acceptability were found for the left- than for the right-facing profiles for retrusive to protrusive and protrusive to retrusive excursions measured in millimeters (p < .001). The bimaxillary position accounted for most of the variance in judgments of acceptability with greater influence on the left than on the right profile.


CONCLUSIONS
With the increasing use of computer-imaging in dental practices, the influence of psychophysical and other environmental variables on perception must be considered.
Anderson
N K
NK
Harvard School of Dental Medicine, Boston, MA 02115, USA.
Evans
C A
CA
Giddon
D B
DB
D000293:Adolescent; D000328:Adult; D003196:Computer Graphics; D004955:Esthetics, Dental; D005145:Face / Q000033:anatomy & histology*; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008310:Malocclusion / Q000523:psychology*; D014796:Visual Perception