Korean J Orthod
First Published Date January 18, 2023
Copyright © The Korean Association of Orthodontists.
1.Hooman Zarif Najafi (Professor)*,
2.Taraneh Estedlal (Resident)†,
3.Maryam Saki‡ (Orthodontist)
4.Maryam Azadi (Private practice)§
*1. Associate Professor in Orthodontics, Orthodontic Research Center, Department of Orthodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran,
†2. Post-graduate Student of Operative Dentistry, Department of Operative Dentistry, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran,
‡3. Orthodontist, Health System Research Center, Shiraz University of Medical Sciences, Shiraz, Iran,
§4. Dentist, Private practice, Shiraz, Iran
Correspondence to:Maryam Saki, School of Dentistry, Qom Abad, Ghasrodasht St., Shiraz, Iran;
Zip Code : 15878- 7195
Tel : +98-9171055418, Fax : +98-9171055418
E-mail : mary_sa68@yahoo.com
Objective: This study evaluated the influence of various gingival displays on the esthetic perception in the presence of upper dental midline discrepancy.
Methods: A smiling image of a male subject was altered digitally to produce five image series: normal smile (series A), decreased tooth show (series B), increased gingival show (series C), maxillary cant (series D), and asymmetric upper lip elevation (series E). In each image series, the midline was deviated to the right and left incrementally. A total of 210 raters (four professional groups and laypersons, n=42 in each group) determined the midline deviation threshold and the attractiveness of midline position in each series.
Results: The right and left thresholds were statistically similar for the symmetrical series (A, B, and C), while for series D, the right threshold was significantly lower. In most rater groups, the mean threshold order was: B>A>E>C>D. In all the series, the raters selected the coincident midline as the most attractive series except for series D, for which 1–2-mm deviations to the left were selected as the most attractive by almost all the groups.
Conclusion: It is crucial to establish the coincident midline position in a symmetrical smile, especially when a gummy smile exists. In the asymmetrical gingival show, a coincident midline might not be the most esthetic midline position.
Keywords: Attractiveness, gingival show, midline deviation, threshold.
Korean J Orthod
First Published Date January 18, 2023
Copyright © The Korean Association of Orthodontists.
1.Hooman Zarif Najafi (Professor)*,
2.Taraneh Estedlal (Resident)†,
3.Maryam Saki‡ (Orthodontist)
4.Maryam Azadi (Private practice)§
*1. Associate Professor in Orthodontics, Orthodontic Research Center, Department of Orthodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran,
†2. Post-graduate Student of Operative Dentistry, Department of Operative Dentistry, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran,
‡3. Orthodontist, Health System Research Center, Shiraz University of Medical Sciences, Shiraz, Iran,
§4. Dentist, Private practice, Shiraz, Iran
Correspondence to:Maryam Saki, School of Dentistry, Qom Abad, Ghasrodasht St., Shiraz, Iran;
Zip Code : 15878- 7195
Tel : +98-9171055418, Fax : +98-9171055418
E-mail : mary_sa68@yahoo.com
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Objective: This study evaluated the influence of various gingival displays on the esthetic perception in the presence of upper dental midline discrepancy.
Methods: A smiling image of a male subject was altered digitally to produce five image series: normal smile (series A), decreased tooth show (series B), increased gingival show (series C), maxillary cant (series D), and asymmetric upper lip elevation (series E). In each image series, the midline was deviated to the right and left incrementally. A total of 210 raters (four professional groups and laypersons, n=42 in each group) determined the midline deviation threshold and the attractiveness of midline position in each series.
Results: The right and left thresholds were statistically similar for the symmetrical series (A, B, and C), while for series D, the right threshold was significantly lower. In most rater groups, the mean threshold order was: B>A>E>C>D. In all the series, the raters selected the coincident midline as the most attractive series except for series D, for which 1–2-mm deviations to the left were selected as the most attractive by almost all the groups.
Conclusion: It is crucial to establish the coincident midline position in a symmetrical smile, especially when a gummy smile exists. In the asymmetrical gingival show, a coincident midline might not be the most esthetic midline position.
Keywords: Attractiveness, gingival show, midline deviation, threshold.