Background: This study aimed to assess the smile dimensions according to gender, age, and the perception of the overall quality and attractiveness of the smile. Methods: A cross-sectional study including 204 Moroccan men and women distributed over five age categories was conducted between January and September 2021. Gender, age, satisfaction and auto-evaluation of the smile were collected using questionnaire. Then, two images of each participant, one at rest and one upon the largest smile were taken. The following distances were measured on the images: length of the lips and width of the mouth at rest and upon smile, gingival and maxillary central incisor displayed upon smile. Results: Dimensions were significantly more important in men. Women displayed significantly more gingiva. With age, the length of the upper lip at rest increased significantly until the age of 50 and the width of the mouth upon smile continued increasing significantly. 74% of the participants were satisfied with their smile. Participants' satisfaction with their smile was not associated with the degree of gingival display. Conclusion: Males have more important dimensions of the lips and the mouth. Females display more gum than males. Age influences the upper lip length at rest which increases up to the age of 50, and the mouth width upon smile which continues to increase with age. Practical Implications: The definition of specific facial norms for each ethnic group considering gender and age groups is essential to establish diagnoses and orthodontic treatment plans.

Background: This study aimed to assess the smile dimensions according to gender, age, and the perception of the overall quality and attractiveness of the smile. Methods: A cross-sectional study including 204 Moroccan men and women distributed over five age categories was conducted between January and September 2021. Gender, age, satisfaction and auto-evaluation of the smile were collected using questionnaire. Then, two images of each participant, one at rest and one upon the largest smile were taken. The following distances were measured on the images: length of the lips and width of the mouth at rest and upon smile, gingival and maxillary central incisor displayed upon smile. Results: Dimensions were significantly more important in men. Women displayed significantly more gingiva. With age, the length of the upper lip at rest increased significantly until the age of 50 and the width of the mouth upon smile continued increasing significantly. 74% of the participants were satisfied with their smile. Participants' satisfaction with their smile was not associated with the degree of gingival display. Conclusion: Males have more important dimensions of the lips and the mouth. Females display more gum than males. Age influences the upper lip length at rest which increases up to the age of 50, and the mouth width upon smile which continues to increase with age. Practical Implications: The definition of specific facial norms for each ethnic group considering gender and age groups is essential to establish diagnoses and orthodontic treatment plans.