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. 2016 May;46(3):137-45.
doi: 10.4041/kjod.2016.46.3.137. Epub 2016 May 20.

Five-year investigation of a large orthodontic patient population at a dental hospital in South Korea

Yongxu Piao  1 , Sung-Jin Kim  1 , Hyung-Seog Yu  1 , Jung-Yul Cha  1 , Hyoung-Seon Baik  1
Affiliations

Five-year investigation of a large orthodontic patient population at a dental hospital in South Korea

Yongxu Piao et al. Korean J Orthod. 2016 May.

Abstract

Objective: The purpose of this study was to investigate the characteristics of orthodontic patients at Yonsei Dental Hospital from 2008 to 2012.

Methods: We evaluated Angle's classification from molar relationships, classification of skeletal malocclusion from the A point-nasion-B point angle, facial asymmetry, and temporomandibular joint disorders (TMDs) from the records of 7,476 patients who received an orthodontic diagnosis. The orthognathic surgery rate, extraction rate, and extraction sites were determined from the records of 4,861 treated patients.

Results: The patient number increased until 2010 and gradually decreased thereafter. Most patients were aged 19-39 years, with a gradual increase in patients aged ≥ 40 years. Angle's Class I, Class II divisions 1 and 2, and Class III malocclusions were observed in 27.7%, 25.6%, 10.6%, and 36.1% patients, respectively, with a gradual decrease in the frequency of Class I malocclusion. The proportion of patients with skeletal Class I, Class II, and Class III malocclusions was 34.3%, 34.3%, and 31.4%, respectively, while the prevalence of facial asymmetry and TMDs was 11.0% and 24.9%, respectively. The orthognathic surgery rate was 18.5%, with 70% surgical patients exhibiting skeletal Class III malocclusion. The overall extraction rate among nonsurgical patients was 35.4%, and the maxillary and mandibular first premolars were the most commonly extracted teeth.

Conclusions: The most noticeable changes over time included a decrease in the patient number after 2010, an increase in the average patient age, and a decrease in the frequency of Angle's Class I malocclusion. Our results suggest that periodic characterization is necessary to meet the changing demands of orthodontic patients.

Keywords: Classification; Epidemiology.

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Conflict of interest statement

The authors report no commercial, proprietary, or financial interest in the products or companies described in this article.

Figures

Figure 1
Figure 1. Patient inclusion flowchart.
TMD, Temporomandibular joint disorder. *Five patients were excluded from the analysis of Angle's classification because of bilaterally missing permanent first molars and/or primary second molars.
See this image and copyright information in PMC

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