# Prevalence of temporomandibular disorders and their association with oral behaviors, anxiety, and depression among medical and dental students in Brazil—a cross-sectional study

## TL;DR

This study found that most medical and dental students in Brazil experience temporomandibular disorders linked to stress, anxiety, depression, and oral behaviors.

## Contribution

The study is the first to explore TMD in Brazilian medical and dental students, linking it to academic stress and mental health.

## Key findings

- 78.6% of students reported TMD symptoms, with 38.5% experiencing both pain and joint-related symptoms.
- TMD symptoms were significantly associated with high oral behaviors, severe anxiety, and moderate to severe depression.
- Anxiety and depression were strongly correlated among the students.

## Abstract

Background: Temporomandibular disorders (TMD) are a group of
musculoskeletal conditions that frequently affect the masticatory muscles and
temporomandibular joints and often result in pain, dysfunction, and decreased
quality of life. University students, particularly those in health-related
fields, may be especially vulnerable to TMD owing to their elevated stress levels
and the presence of oral parafunctional behaviors. Psychosocial factors such as
anxiety and depression are recognized as important contributors to the onset and
exacerbation of TMD symptoms. Methods: This cross-sectional study
included 182 undergraduate students enrolled in medical and dental programmes at
a private university in Brazil. The participants completed an online self-report
questionnaire that included the Diagnostic Criteria for Temporomandibular
Disorders (DC/TMD) Symptom Questionnaire, Oral Behavior Checklist (OBC),
Generalized Anxiety Disorder Scale (GAD-7), and Patient Health Questionnaire
(PHQ-9). Associations among TMD symptoms, oral behaviors, anxiety, and depression
were analyzed using the chi-square and Fisher’s exact tests (α = 0.05).
Results: A total of 78.6% of the participants reported TMD symptoms,
with 38.5% experiencing both pain-related and joint-related symptoms. Oral
behaviors were reported by 98.9% of the students, while symptoms of anxiety and
depression were present in 74.7% and 65.4% of the sample, respectively.
Significant associations were found between painful/joint TMD and higher levels
of oral behaviors (p < 0.001), severe anxiety (p = 0.015),
and moderately severe to severe depression (p = 0.016). Oral behaviors
were more frequent in students in later semesters (p = 0.006) and were
associated with anxiety (p < 0.001) and depression (p <
0.001). A strong correlation was observed between anxiety and depression
(p < 0.001). Conclusions: This study confirmed a high
prevalence of temporomandibular disorder (TMD) symptoms among medical and dental
students. Pain-related and joint-related TMD symptoms were significantly
associated with high-frequency oral behaviors, as well as with moderate to severe
levels of anxiety and depression.