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Original Research (Preprint)

Vol. 1 No. 2 (2025): Regular Issue

Impact of malocclusion traits on the quality of life, anxiety, and depression among the Mongolian population

Submitted
December 23, 2025
Published
December 31, 2025

Abstract

The purpose of our population-based cross-sectional study was to assess the association between malocclusion and the quality of life (QoL), anxiety, and depression. The study was conducted between July and October 2020 in Mongolia. Clinical examinations were carried out by orthodontists. Using a millimeter ruler, excessive and reverse overjet were recorded as abnormal. Crowding was recorded for the incisor and posterior segments of each jaw. Anterior diastema was diagnosed when there was a space of at least 1 mm between incisors in either arch. Facial profile (straight, convex, and concave) was determined by vision using soft tissue reference points. Each participant completed the World Health Organization Quality of Life (WHO-QoL-BREF) and the Hospital Anxiety and Depression Scale (HADS), and an orthodontic questionnaire. The study consists of 436 participants aged between 13 and 65 years (mean age = 39.6±14.8), the majority were females, 297 (68.1%). The prevalence of malocclusion, in general, was 371 (85.1%). In terms of the prevalence of the malocclusion traits: abnormal overjet was 245(56.2%), crowded dentition was 118 (27.1%), and diastema was 75 (17.2%). Participants with malocclusions had increased depression scores (p = 0.008). Participants with diastema had decreased QoL in physical and social domains (p = 0.022, p = 0.020). Moreover, reverse correlations were found between depression scores and QoL in psychological, social, and environmental domains in the population with malocclusion traits (p = 0.035, p = 0.0039, p = 0.002). We found that the prevalence of malocclusion was 85.1% in the general population. Participants with malocclusion have decreased QoL, which is associated with increased depression scores.

References

  1. Agou, S., Locker, D., Streiner, D. L., & Tompson, B. (2008). Impact of self-esteem on the oral-health-related quality of life of children with malocclusion. Am J Orthod Dentofacial Orthop, 134(4), 484-489. https://doi.org/10.1016/j.ajodo.2006.11.021
  2. Alhammadi, M. S., Halboub, E., Fayed, M. S., Labib, A., & El-Saaidi, C. (2018). Global distribution of malocclusion traits: A systematic review. Dental Press J Orthod, 23(6), 40 e41-40 e10. https://doi.org/10.1590/2177-6709.23.6.40.e1-10.onl
  3. Araki, M., Yasuda, Y., Ogawa, T., Tumurkhuu, T., Ganburged, G., Bazar, A., . . . Moriyama, K. (2017). Associations between Malocclusion and Oral Health-Related Quality of Life among Mongolian Adolescents. Int J Environ Res Public Health, 14(8). https://doi.org/10.3390/ijerph14080902
  4. Bilgic, F., Gelgor, I. E., & Celebi, A. A. (2015). Malocclusion prevalence and orthodontic treatment need in central Anatolian adolescents compared to European and other nations' adolescents. Dental Press J Orthod, 20(6), 75-81. https://doi.org/10.1590/2177-6709.20.6.075-081.oar
  5. Ekuni, D., Furuta, M., Irie, K., Azuma, T., Tomofuji, T., Murakami, T., . . . Morita, M. (2011). Relationship between impacts attributed to malocclusion and psychological stress in young Japanese adults. Eur J Orthod, 33(5), 558-563. https://doi.org/10.1093/ejo/cjq121
  6. Grando, G., Young, A. A., Vedovello Filho, M., Vedovello, S. A., & Ramirez-Yanez, G. O. (2008). Prevalence of malocclusions in a young Brazilian population. Int J Orthod Milwaukee, 19(2), 13-16. http://www.ncbi.nlm.nih.gov/pubmed/18686678
  7. Johal, A., Cheung, M. Y., & Marcene, W. (2007). The impact of two different malocclusion traits on quality of life. Br Dent J, 202(2), E2. https://doi.org/10.1038/bdj.2007.33
  8. Kenealy, P. M., Kingdon, A., Richmond, S., & Shaw, W. C. (2007). The Cardiff dental study: a 20-year critical evaluation of the psychological health gain from orthodontic treatment. Br J Health Psychol, 12(Pt 1), 17-49. https://doi.org/10.1348/135910706X96896
  9. Lew, K. K., Foong, W. C., & Loh, E. (1993). Malocclusion prevalence in an ethnic Chinese population. Aust Dent J, 38(6), 442-449. https://doi.org/10.1111/j.1834-7819.1993.tb04759.x
  10. Liu, B. C., Lee, I. C., Lo, L. J., & Ko, E. W. (2019). Investigate the oral health impact and quality of life on patients with malocclusion of different treatment needs. Biomed J, 42(6), 422-429. https://doi.org/10.1016/j.bj.2019.05.009
  11. Liu, Z., McGrath, C., & Hagg, U. (2009). The impact of malocclusion/orthodontic treatment need on the quality of life. A systematic review. Angle Orthod, 79(3), 585-591. https://doi.org/10.2319/042108-224.1
  12. Macgregor, F. C. (1970). Social and psychological implications of dentofacial disfigurement. Angle Orthod, 40(3), 231-233. https://doi.org/10.1043/0003-3219(1970)040<0231:SAPIOD>2.0.CO;2
  13. Mathes, E. W., & Kahn, A. (1975). Physical attractiveness, happiness, neuroticism, and self-esteem. J Psychol, 90(1st Half), 27-30. https://doi.org/10.1080/00223980.1975.9923921
  14. Neto, A., Mourão, R., Sousa, R., Vajgel, B., & Cimões, R. (2017). The Impact Of Malocclusion On Quality Of Life And Life Satisfaction. International Archives of Medicine, 10. https://doi.org/10.3823/2492
  15. O'Brien, C., Benson, P. E., & Marshman, Z. (2007). Evaluation of a quality of life measure for children with malocclusion. J Orthod, 34(3), 185-193; discussion 176. https://doi.org/10.1179/146531207225022185
  16. Proffit, W. R., Fields, H. W., Jr., & Moray, L. J. (1998). Prevalence of malocclusion and orthodontic treatment need in the United States: estimates from the NHANES III survey. Int J Adult Orthodon Orthognath Surg, 13(2), 97-106. http://www.ncbi.nlm.nih.gov/pubmed/9743642
  17. Shaw, W. C., Richmond, S., Kenealy, P. M., Kingdon, A., & Worthington, H. (2007). A 20-year cohort study of health gain from orthodontic treatment: psychological outcome. Am J Orthod Dentofacial Orthop, 132(2), 146-157. https://doi.org/10.1016/j.ajodo.2007.04.009
  18. Silva, L. F., Thomaz, E. B., Freitas, H. V., Pereira, A. L., Ribeiro, C. C., & Alves, C. M. (2016). Impact of Malocclusion on the Quality of Life of Brazilian Adolescents: A Population-Based Study. PLoS One, 11(9), e0162715. https://doi.org/10.1371/journal.pone.0162715
  19. Tang, E. L. (1994). The prevalence of malocclusion amongst Hong Kong male dental students. Br J Orthod, 21(1), 57-63. https://doi.org/10.1179/bjo.21.1.57
  20. Thilander, B., & Myrberg, N. (1973). The prevalence of malocclusion in Swedish schoolchildren. Scand J Dent Res, 81(1), 12-21. https://doi.org/10.1111/j.1600-0722.1973.tb01489.x
  21. WHO. (2010). What is the burden of oral disease? Oral disease burdens and common risk factors. https://www.who.int/oral_health/disease_burden/global/en
  22. World Health Organization. Division of Mental, H. (1996). WHOQOL-BREF : introduction, administration, scoring and generic version of the assessment : field trial version, December 1996. In. Geneva: World Health Organization.
  23. WR, P. (Ed.). (2000). Contemporary Orthodontics (3rd ed.).
  24. Zhang, L., Liu, X., Zheng, G. J., Zhou, L., Lin, D. Y., Wang, X. D., & He, H. (2012). Eysenck personality and psychosocial status of adult patients with malocclusion. Asian Pac J Trop Med, 5(2), 151-156. https://doi.org/10.1016/S1995-7645(12)60015-7
  25. Zhang, M., McGrath, C., & Hagg, U. (2006). The impact of malocclusion and its treatment on quality of life: a literature review. Int J Paediatr Dent, 16(6), 381-387. https://doi.org/10.1111/j.1365-263X.2006.00768.x