Changes in the orofacial soft tissue after the movement from repose to smiling was studied from standardized photographs of a group of 101 young adults to determine norms for distension of the nose, lips, and chin during smiling. Categorical comparisons of facial animation and lip-tooth display were then made between male and female and between untreated and orthodontically treated subgroups. For the total sample, the nose increased in width by 14% and the tip moved inferiorly. The upper lip elevated to 80% of its original length to display 10 mm of maxillary incisor. Mouth width increased to 130% of its original width, and the lips separated approximately 12 mm. In general, women exhibited a greater degree of facial animation than men. Orthodontically treated subjects displayed more maxillary incisor and gingiva than the untreated group, but did not exhibit a greater degree of facial animation than the untreated group. The percentage of upper lip elevation was found to be responsible for less than 10% of the variability in maxillary incisor exposure during a smile.