To adapt and estimate the psychometric properties of Utrecht Questionnaire for esthetic outcome assessment in rhinoplasty (OAR) to assess concern about smile appearance and to estimate the influence of demographic characteristics on this concern in adults. This was a cross-sectional observational study. Individuals aged between 18 and 40 years participated in the study. The Portuguese version of OAR was adapted for smile assessment in dental practice and was named Questionnaire for Outcome Assessment of Smile Aesthetic (OA-Smile). Data validity was estimated using factorial validity [confirmatory factor analysis (CFA)-CFI, Tucker-Lewis index (TLI), SRMR)] and convergent validity (average variance extracted). Reliability was assessed using the alpha ordinal coefficient (αordinal) and the omega coefficient (ω). A structural model was elaborated to assess the contribution of demographic characteristics to smile appearance concerns. Model fit was evaluated, and the z-test (α = 5%) was used to estimate the significance of the path estimates (β). 2.523 subjects participated in the study [mean age = 32.86 (SD = 11.39) years, 68.1% female]. The factor model of orofacial appearance (OA)-Smile presented an adequate fit to the data [CFA: comparative fit index (CFI) = 0.99, TLI = 0.99, SRMR ≤ 0.05]. Convergent validity (AVE ≥ 0.80) and reliability (αordinal and ω ≥ 0.85) were adequate. The structural model presented an acceptable fit (CFI = 0.974; TLI = 0.991 and SRMR = 0.053). Women, younger people, single people, people with lower income, people using dental prostheses, undergoing dental treatment, and those who do not like their smile were more concerned about their smile appearance. Nonprobability sampling, online data collection, and cross-sectional design are considered limitations of the study. OA-Smile is a suitable scale to assess smile appearance concerns, and the data obtained with this scale were valid and reliable. Demographic characteristics should be considered when measuring concerns about smile appearance.