Korean J Orthod.  2017 Mar;47(2):100-107. 10.4041/kjod.2017.47.2.100.

Smile esthetics: Evaluation of long-term changes in the transverse dimension

Affiliations
  • 1Department of Orthodontics, Tufts University School of Dental Medicine, Boston, MA, USA. sercan.akyalcin@tufts.edu
  • 2Private Practice, Queensbury, NY, USA.
  • 3Department of Orthodontics, School of Dentistry, University of Texas Health Science Center, Houston, TX, USA.
  • 4Private Practice, Arlington, TX, USA.

Abstract


OBJECTIVE
To analyze the long-term changes in maxillary arch widths and buccal corridor ratios in orthodontic patients treated with and without premolar extractions.
METHODS
The study included 53 patients who were divided into the extraction (n = 28) and nonextraction (n = 25) groups. These patients had complete orthodontic records from the pretreatment (T1), posttreatment (T2), and postretention (T3) periods. Their mean retention and postretention times were 4 years 2 months and 17 years 8 months, respectively. Dental models and smiling photographs from all three periods were digitized to compare the changes in three dental arch width measurements and three buccal corridor ratios over time between the extraction and nonextraction groups. Data were analyzed using analysis of variance tests. Post-hoc multiple comparisons were made using Bonferroni correction.
RESULTS
Soft-tissue extension during smiling increased with age in both groups. The maximum dental width to smile width ratio (MDW/SW) also showed a favorable increase with treatment in both groups (p < 0.05), and remained virtually stable at T3 (p > 0.05). According to the MDW/SW ratio, the mean difference in the buccal corridor space of the two groups was 2.4 ± 0.2% at T3. Additionally, no significant group × time interaction was found for any of the buccal corridor ratios studied.
CONCLUSIONS
Premolar extractions did not negatively affect transverse maxillary arch widths and buccal corridor ratios. The long-term outcome of orthodontic treatment was comparable between the study groups.

Keyword

Esthetics; Stability; Extraction

MeSH Terms

Bicuspid
Dental Arch
Dental Models
Esthetics*
Humans
Smiling

Figure

  • Figure 1 Maxillary arch width measurements used in this study. ICW, Intercanine width; IPW, interpremolar width; IMW, intermolar width.

  • Figure 2 Linear measurements made on smile photographs. SW, Smile width; MDW, maximum dental width; ICW, intercanine width.

  • Figure 3 Group × time interactions for the maxillary arch width measurements of the extraction (black line) and nonextraction (gray line) groups. ICW, Intercanine width; IPW, interpremolar width; IMW, intermolar width.

  • Figure 4 Group × time interactions for the buccal corridor ratios of the extraction (black line) and nonextraction (gray line) groups. ICW, Intercanine width; SW, smile width; MDW, maximum dental width.


Cited by  1 articles

A systematic review of the accuracy and efficiency of dental movements with Invisalign®
Lidia Galan-Lopez, Jorge Barcia-Gonzalez, Eliseo Plasencia
Korean J Orthod. 2019;49(3):140-149.    doi: 10.4041/kjod.2019.49.3.140.


Reference

1. Ioi H, Nakata S, Counts AL. Effects of buccal corridors on smile esthetics in Japanese. Angle Orthod. 2009; 79:628–633.
Article
2. Martin AJ, Buschang PH, Boley JC, Taylor RW, McKinney TW. The impact of buccal corridors on smile attractiveness. Eur J Orthod. 2007; 29:530–537.
Article
3. Zange SE, Ramos AL, Cuoghi OA, de Mendonça MR, Suguino R. Perceptions of laypersons and orthodontists regarding the buccal corridor in long- and short-face individuals. Angle Orthod. 2011; 81:86–90.
Article
4. Chang CA, Fields HW Jr, Beck FM, Springer NC, Firestone AR, Rosenstiel S, et al. Smile esthetics from patients' perspectives for faces of varying attractiveness. Am J Orthod Dentofacial Orthop. 2011; 140:e171–e180.
Article
5. Parekh SM, Fields HW, Beck M, Rosenstiel S. Attractiveness of variations in the smile arc and buccal corridor space as judged by orthodontists and laymen. Angle Orthod. 2006; 76:557–563.
6. Ioi H, Kang S, Shimomura T, Kim SS, Park SB, Son WS, et al. Effects of buccal corridors on smile esthetics in Japanese and Korean orthodontists and orthodontic patients. Am J Orthod Dentofacial Orthop. 2012; 142:459–465.
Article
7. Ghafari JG. Emerging paradigms in orthodontics-an essay. Am J Orthod Dentofacial Orthop. 1997; 111:573–580.
8. Spahl TJ. Premolar extractions and smile esthetics. Am J Orthod Dentofacial Orthop. 2003; 124:16A–17A. author reply 17A.
9. Johnson DK, Smith RJ. Smile esthetics after orthodontic treatment with and without extraction of four first premolars. Am J Orthod Dentofacial Orthop. 1995; 108:162–167.
Article
10. Kim E, Gianelly AA. Extraction vs nonextraction: arch widths and smile esthetics. Angle Orthod. 2003; 73:354–358.
11. Gianelly AA. Arch width after extraction and nonextraction treatment. Am J Orthod Dentofacial Orthop. 2003; 123:25–28.
Article
12. Yang IH, Nahm DS, Baek SH. Which hard and soft tissue factors relate with the amount of buccal corridor space during smiling? Angle Orthod. 2008; 78:5–11.
Article
13. Akyalcin S, Erdinc AE, Dincer B, Nanda RS. Do long-term changes in relative maxillary arch width affect buccal-corridor ratios in extraction and nonextraction treatment? Am J Orthod Dentofacial Orthop. 2011; 139:356–361.
Article
14. Meyer AH, Woods MG, Manton DJ. Maxillary arch width and buccal corridor changes with orthodontic treatment. Part 1: differences between premolar extraction and nonextraction treatment outcomes. Am J Orthod Dentofacial Orthop. 2014; 145:207–216.
Article
15. Janson G, Branco NC, Fernandes TM, Sathler R, Garib D, Lauris JR. Influence of orthodontic treatment, midline position, buccal corridor and smile arc on smile attractiveness. Angle Orthod. 2011; 81:153–161.
Article
16. Krishnan V, Daniel ST, Lazar D, Asok A. Characterization of posed smile by using visual analog scale, smile arc, buccal corridor measures, and modified smile index. Am J Orthod Dentofacial Orthop. 2008; 133:515–523.
Article
17. Sarver DM, Ackerman MB. Dynamic smile visualization and quantification: part 1. Evolution of the concept and dynamic records for smile capture. Am J Orthod Dentofacial Orthop. 2003; 124:4–12.
Article
18. Sarver DM, Ackerman MB. Dynamic smile visualization and quantification: part 2. Smile analysis and treatment strategies. Am J Orthod Dentofacial Orthop. 2003; 124:116–127.
Article
19. Dahlberg G. Statistical methods for medical and biological students. London, UK: Allen and Unwin Publishing;1940. p. 122–132.
20. Bishara SE, Cummins DM, Jakobsen JR. The morphologic basis for the extraction decision in Class II, division 1 malocclusions: a comparative study. Am J Orthod Dentofacial Orthop. 1995; 107:129–135.
Article
21. Saelens NA, De Smit AA. Therapeutic changes in extraction versus non-extraction orthodontic treatment. Eur J Orthod. 1998; 20:225–236.
Article
22. Francisconi MF, Janson G, Freitas KM, Oliveira RC, Oliveira RC, Freitas MR, et al. Overjet, overbite, and anterior crowding relapses in extraction and nonextraction patients, and their correlations. Am J Orthod Dentofacial Orthop. 2014; 146:67–72.
Article
23. Maulik C, Nanda R. Dynamic smile analysis in young adults. Am J Orthod Dentofacial Orthop. 2007; 132:307–315.
Article
Full Text Links
  • KJOD
Actions
Cited
CITED
export Copy
Close
Share
  • Twitter
  • Facebook
Similar articles
Copyright © 2024 by Korean Association of Medical Journal Editors. All rights reserved.     E-mail: koreamed@kamje.or.kr