Laypersons and dentists' perception of smile esthetics in spacing between maxillary central and lateral incisors teeth: a cross-sectional study

A smile is an important component of facial attractiveness. However, perceptions of gaps between adjacent teeth, known as diastema, may vary among different individuals and regions depending on cultural or other factors. This study aimed to evaluate perceptions of midline diastema and lateral diastema among individuals of different ages, genders, education levels, and occupations. A cross-sectional study based on a survey with manipulated pictures was conducted at the Department of Prosthodontics, Islamic International Dental Hospital and College, Islamabad, Pakistan, from 1 March to 31 May 2020. The surveyed population included dentists and laypeople and comprised 198 (44.4%) men and 248 (55.6%) women with a mean age of 30.52±13.46 years. Data were analyzed using the Statistical Package for Social Sciences (SPSS), version 23.0 (IBM Corporation, Armonk, USA) for Microsoft Windows. The statistical hypothesis test and chi-square test were used to validate significant differences (p≤0.05). Of the 446 participants who completed the survey, 384 (86.09%) preferred a midline diastema of 0mm, and 320 (71.74%) preferred a lateral diastema of 0mm. Approximately 71.71% of the male and 83.6% of the female participants preferred a maxillary midline diastema of 0mm. A significantly (P≤0.05) greater percentage of dentists (91.12%) than laypeople (70.40%) rated a midline diastema of 0mm as most attractive. The negative perceptions of midline and lateral diastema appear to be related to their location and width. The participants rated a diastema of 0mm more attractive than a diastema of 1.5mm or 2mm.