The midline from the perspective of the layperson and dental surgeon




Esthetics dental, Smiling, Orthodontics


Aim: The objective of this research was to evaluate the midline from the perspectives of the layperson and the dental surgeon.

Methods: The survey was conducted from August to December 2018 in Parnaíba, PI, Brazil. An image of a female smile was used, in which changes were made in the upper dental midline, every 1 mm up to 4 mm, and in the incisal angulation, every 5 degrees up to 15 degrees, to the left side. The images were cut and formed into two groups, one showing a smile with no lip filter (G1) and another with a smile with a lip filter (G2). These were then shown to 334 lay people and 25 dentists for evaluation with scores from 0 to 10, with scores from 0 to 5.9 for an unacceptable smile and from 6 to 10 for an acceptable smile.

Results: Dental surgeons were more critical when analyzing the images and detected deviations from 1mm and 5 degrees in both groups G1 and G2. Laypeople noticed deviations from 2mm and 15 degrees on G1 and deviations from 3mm and 10 degrees on G2.

Conclusion: Dental surgeons and laypeople are able to assess midline deviations with the minimum deviation present. Dentists were more critical in detecting midline deviation when analyzing photos.



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How to Cite

Lira, A. de L. S. de, Araújo , Ítalo I. de C., & Araújo, I. Íris de C. (2022). The midline from the perspective of the layperson and dental surgeon. Arquivos Em Odontologia, 57, 132–140.




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