Association between malocclusion and symptom of TMD
- VernacularTitle:Зуултын гажигийг эрүүний үений эмгэгийн шинж тэмдэгтэй холбон судалсан нь
- Author:
Ochirbal M
1
;
Batbayar B
2
;
Od B
1
Author Information
1. Department of Orthodontics, School of Dentistry, MNUMS
2. School of Dentistry, MNUMS
- Publication Type:Other Types
- Keywords:
Angle’s classification;
Index of Orthodontic Treatment Need;
Andrew’s six keys;
Occlusion;
Temporoman dibular joint
- From:
Mongolian Journal of Health Sciences
2025;88(4):171-177
- CountryMongolia
- Language:Mongolian
-
Abstract:
Background:The first supposition of a possible relationship between occlusion and TMJ (temporomandibular joint)
function was suggested by Costen, who hypothesized that changes in dental condition (loss of vertical dimension) can
lead to symptoms of temporomandibular disorders (TMD). Symptoms of temporomandibular disorders are more com
mon in women, with a female-to-male ratio ranging from 2:1 to 8:1. Temporomandibular disorders occur in 25-38% of
the general population. The reason for conducting this study is that no research has been conducted in Mongolia on the
relationship between malocclusion and TMJ.
Aim:This study aimed to investigate the association between malocclusion and temporomandibular disorders.
Materials and Methods:The study was conducted using a case-control design, and patients requiring orthodontic treat
ment who visited the Orthodontics Department of the Center Hospital of the Dentistry, Mongolian National University of
Medical Sciences were included in the case group, while relatively healthy individuals with normal occlusion who had
not undergone orthodontic treatment were included in the control group. The sample size for each case and control group
was calculated to be 20 people, for a total of 40 people aged 20-30. The need for orthodontic treatment was determined by
the IOTN index (Index of Orthodontic Treatment Need). Relatively healthy occlusion was defined according to Andrew’s
six keys. The condition of the temporomandibular joint was determined using a questionnaire and physical examination.
Results:The mean age of the study participants was 24.4±3.7 years in the malocclusion group and 26.0±3.6 years in
the control group, 45% (n=8) of the malocclusion group were male and 40% (n=9) of the control group were male. The
indicators of malocclusion, such as increased overjet, decreased overjet, increased overbite and mouth breathing were
statistically significantly different between the malocclusion group and the control group (p<0.05). Logistic regression
analysis showed that CII (OR=11.66, p=0.007) and CIII (OR=16.33, p=0.017) occlusion, increased overbite (OR=6.87,
p=0.025) and mouth breathing (OR=4.22, p=0.042) had an impact on the occurrence of TMJ noise in both vertical and
horizontal directions.
Conclusions:1. Among the study participants, Angle’s Class I accounted for 50% (the highest percentage), while Angle’s Class III
accounted for 20% (the lowest percentage). But Angle’s Class II accounted for 30%.
2. Symptoms of temporomandibular joint disorder were statistically significantly higher in the case group (p<0.05). 3.
People with Angle’s Class II and Class III were 11-16 times more likely to develop temporomandibular joint (TMJ)
noise, a symptom of TMD, compared to people with normal occlusion.
- Full text:2025052212443388198171-177.pdf
