Orthodontic treatment positively influences behavior and perception on age recognition.

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.