Maulik Christopher, Nanda Ravindra
Department of Craniofacial Sciences; Chair, Division of Orthodontics, University of Connecticut School of Dental Medicine, Farmington, CT 06030-1725, USA.
Am J Orthod Dentofacial Orthop. 2007 Sep;132(3):307-15. doi: 10.1016/j.ajodo.2005.11.037.
Current trends in orthodontics place greater emphasis on smile esthetics, yet few studies provide averages and norms for the smile. The purposes of this study were to provide averages for various components of the smile and to compare some of these in orthodontically treated and untreated groups. Also, smiles of patients with and without rapid maxillary expansion (RME) were compared.
Video equipment was used to capture smiles in 230 subjects.
The majority of subjects showed on smile flat smile arc, back to the second maxillary premolar, and an 11% buccal corridor. The orthodontically treated group showed a statistically significant more parallel smile arc compared with the untreated group. The RME group had statistically significant less buccal corridor compared with the nonexpanded subjects.
This study helps to establish dynamic norms for the smile and shows that orthodontic treatment might not flatten the smile arc as previously suggested, and, furthermore, that RME appears to be associated with a decreased buccal corridor.
正畸学的当前趋势更加强调微笑美学，但很少有研究提供微笑的平均值和标准。本研究的目的是提供微笑各个组成部分的平均值，并比较正畸治疗组和未治疗组中的一些指标。此外，还比较了接受和未接受快速上颌扩弓（RME）患者的微笑。
使用视频设备捕捉230名受试者的微笑。
大多数受试者微笑时微笑弧度平坦，延伸至第二上颌前磨牙，颊侧间隙为11%。与未治疗组相比，正畸治疗组的微笑弧度在统计学上更平行。与未扩弓的受试者相比，RME组的颊侧间隙在统计学上显著更小。
本研究有助于建立微笑的动态标准，并表明正畸治疗可能不会像之前所认为的那样使微笑弧度变平，此外，RME似乎与颊侧间隙减小有关。
