ABSTRACT Objectives To investigate how smiles and occlusion influence behavioral response and the perception of age. Materials and Methods Adult laypeople (N = 80; 19–84 years) were asked to “estimate the age” and “select the younger and healthier face” from pretreatment (pre-Tx) and posttreatment (post-Tx) neutral (N) and smiling (S) face photographs of female orthodontic patient models (N = 18; 25–66 years), along with eye tracking. A survey was conducted to monitor subjective perceptions of age. Age estimation toward peers and nonpeers was compared among young (19–39 years), middle-aged (40–59 years), and older adult (≥60 years) participants. Results Greater numbers of post-Tx faces were rated as younger than the actual age when compared with pre-Tx faces ( P < .001). Post-Tx/S was most frequently selected as looking younger and healthier ( P < .001). Fixation time on the mouth region was significantly higher for S than for N during the tasks ( P < .001). For older adults, increase in the ratio of being estimated as younger following Tx was significantly higher for peers than for nonpeers ( P < .05). Conclusions Individuals with ideal occlusion and smiling were more likely to be perceived as younger by others, indicating a positive influence of orthodontic treatment on age perception. Older adults may benefit from orthodontic treatment for improving their smiles and for being judged younger by others.
Kim et al. (Thu,) studied this question.