Shuying Yang1, Yunfei Guo2, Xianrui Yang3, Feng Zhang4, Jian Wang5, Jingyi Qiu3, Juan Li6. 1. Postgraduate student, Department of Prosthodontics, State Key Laboratory of Oral Diseases, West China College of Stomatology, Sichuan University, Chengdu, China. 2. Resident, Lanzhou Hospital of Stomatology, Lanzhou, China. 3. Postgraduate student, Department of Orthodontics, State Key Laboratory of Oral Diseases, West China college of Stomatology, Sichuan University, Chengdu, China. 4. Private practice, Hangzhou, China. 5. Associate professor, Department of Prosthodontics, State Key Laboratory of Oral Diseases, West China College of Stomatology, Sichuan University, Chengdu, China. 6. Associate professor, Department of Orthodontics, State Key Laboratory of Oral Diseases, West China College of Stomatology, Sichuan University, Chengdu, China. Electronic address: lijuan@scu.edu.cn.
Abstract
INTRODUCTION: The purpose of this study was to analyze the effect of mesiodistal angulation of the maxillary central incisors on the smiling esthetics in young adults. METHODS: Frontal smile photographs of a young man and a young woman were digitally modified to produce 28 smile images that were grouped into 4 series. These images were judged using visual analog scales by 52 orthodontists and 61 laypeople. The effects of the judges' professions, subjects' sexes, and photograph framings on the appreciation of smile esthetics with different mesiodistal angulations of the maxillary central incisors were evaluated. The data were analyzed with paired t tests, Dunnett t tests, and independent samples t tests; statistical significance was set at P <0.05. RESULTS: The images were ranked less attractive as the mesiodistal angulation of the maxillary central incisors increased during smiling. No relationship was found between the judges' professions and the esthetic evaluations of incisal angulation, but the statistical analysis showed that both the subject's sex and the photograph framing were significant variables (P <0.05). CONCLUSIONS: The mesiodistal angulation of the maxillary central incisors plays an essential role in smile esthetics in the frontal view. When formulating treatment plans, orthodontists should never underestimate the influence of mesiodistal angulation on smile attractiveness.
INTRODUCTION: The purpose of this study was to analyze the effect of mesiodistal angulation of the maxillary central incisors on the smiling esthetics in young adults. METHODS: Frontal smile photographs of a young man and a young woman were digitally modified to produce 28 smile images that were grouped into 4 series. These images were judged using visual analog scales by 52 orthodontists and 61 laypeople. The effects of the judges' professions, subjects' sexes, and photograph framings on the appreciation of smile esthetics with different mesiodistal angulations of the maxillary central incisors were evaluated. The data were analyzed with paired t tests, Dunnett t tests, and independent samples t tests; statistical significance was set at P <0.05. RESULTS: The images were ranked less attractive as the mesiodistal angulation of the maxillary central incisors increased during smiling. No relationship was found between the judges' professions and the esthetic evaluations of incisal angulation, but the statistical analysis showed that both the subject's sex and the photograph framing were significant variables (P <0.05). CONCLUSIONS: The mesiodistal angulation of the maxillary central incisors plays an essential role in smile esthetics in the frontal view. When formulating treatment plans, orthodontists should never underestimate the influence of mesiodistal angulation on smile attractiveness.