Influence of dental education on eye gaze distribution when observing facial profiles with varying degrees of lip protrusion

Objectives: The purpose of the present study was to investigate the influence of dental education on eye gaze distribution when perceiving facial profile images with varying degrees of lip protrusion. Methods: Fifty-one subjects with dental education (dental-education group) and 47 without dental education (no-dental-education group) were included in this study. The eye gaze distribution of the subjects was recorded for 10 seconds using a non-contact eye tracker when determining whether or not the subjects judged each various facial profile image inappropriate. The facial profile images had varying degrees of upper-lip and lower-lip protrusion. The frequency of eye fixation (lasting >0.06 seconds) was counted. The duration was measured as the total time of eye fixation. The facial images were divided into 4 regions of interest (ROIs): the forehead (ROI-I); the orbit and nose root (ROI-II); the nose tip and upper lip (ROI-III); and the lower lip and chin (ROI-IV). The frequency and duration of eye fixation on each ROI was compared. Results: The frequency of eye fixation on ROI-II was greater in comparison to ROI-I and ROI-IV. The frequency of eye fixation on ROI-III was also greater in comparison to ROI-I and ROI-IV. The duration of eye fixation on ROI-III in the dental-education group was longer in comparison to the no-dental-education group. Conclusions: Dental education influenced the eye fixation on the nose tip and upper lip when perceiving facial profile images.