UNIVERSIDADE ESTADUAL PAULISTA
“JÚLIO DE MESQUITA FILHO”
Instituto de Ciência e Tecnologia
Campus de São José dos Campos
ORIGINAL ARTICLE DOI: https://doi.org/10.4322/bds.2025.e4501
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Braz Dent Sci 2025 Apr/Jun; 28 (2): e4501
This is an Open Access article distributed under the terms of the Creative Commons Attribution license (https://creativecommons.org/licenses/by/4.0/), which permits
unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Analysis of the relationship between anxiety symptoms and
temporomandibular disorder in undergraduate dental students
Análise da relação entre os sintomas de ansiedade e as desordens temporomandibulares em alunos de um curso de
graduação em odontologia
Letícia Lima Morais CARVALHO1 , Izabela da COSTA1 , Ariane Aurélia Teixeira CARVALHAIS1 ,
Ronaldo Luis Almeida de CARVALHO1 , Jean Soares MIRANDA1
1 - Departamento de Odontologia, Universidade Federal de Juiz de Fora, campus Governador Valadares, Governador Valadares - MG, Brazil
How to cite: Carvalho LLM, Costa I, Carvalhais AAT, Caravalho RLA, Miranda JS. Analysis of the relationship between anxiety symptoms and
temporomandibular disorder in undergraduate dental students. Braz Dent Sci. 2025;28(2):e4501. https://doi.org/10.4322/bds.2025.e4501
ABSTRACT
Objective: To evaluate, through the application of validated questionnaires, whether the level of anxiety
symptoms was associated with the occurrence of painful Temporomandibular Disorders (TMDs) in
undergraduate dental students. Material and Methods: To check the occurrence of symptoms of anxiety
disorders the GAD-7 (Generalized Anxiety Disorder – 7) questionnaire was applied and to diagnose TMDs
the DC/TMD (Diagnostic Criteria for TMDs) was administered to 60 patients. Participants were divided into
two groups: control (Co), composed of students without TMD diagnosis (n=30), and experimental group
(Exp), composed of students with a TMD diagnosis (n=30). The acquired data underwent descriptive analysis
and statistical treatment using chi-square or Fisher’s exact tests. Results: The results showed a signicant
relationship between moderate and severe anxiety levels with the occurrence of TMDs (p < 0.001), not
being related to a specic type of these disorders (muscular and/or joint) (p = 0.071). Regarding sex, it
was observed that it does not inuence the occurrence of TMDs (p = 0.778). However, sex was related to
anxiety levels (p < 0.001), with males in our study being associated with moderate and severe levels of
anxiety symptoms. Conclusion: It was concluded that anxiety is associated with the occurrence of painful
TMDs in dental students, with moderate and severe levels of anxiety symptoms being more prevalent in
individuals with TMD.
KEYWORDS
Anxiety; Dentistry students; Orofacial pain; Stress; Temporomandibular Joint Dysfunction Syndrome.
RESUMO
Objetivo: Avaliar, por meio da aplicação de questionários validados, se o nível de sintomas de ansiedade está
associado à ocorrência de Desordens Temporomandibulares (DTMs) dolorosas em estudantes de odontologia
de graduação. Material e Métodos: Para vericar a ocorrência de sintomas de transtornos de ansiedade, foi
aplicado o questionário GAD-7 (Generalized Anxiety Disorder - 7), e para diagnosticar as DTMs, utilizou-se
o DC/TMD (Diagnostic Criteria for Temporomandibular Disorders) em 60 pacientes. Os participantes foram
divididos em dois grupos: controle (Co), composto por estudantes sem diagnóstico de DTM (n=30), e grupo
experimental (Exp), composto por estudantes com diagnóstico de DTM (n=30). Os dados adquiridos foram
submetidos a análise descritiva e tratamento estatístico utilizando os testes qui-quadrado ou exato de Fisher.
Resultados: Os resultados mostraram uma relação signicativa entre níveis moderados e graves de ansiedade
com a ocorrência de DTMs (p < 0,001), não estando relacionados a um tipo especíco dessas desordens
(muscular e/ou articular) (p = 0,071). Em relação ao sexo, observou-se que não inuencia a ocorrência de
DTMs (p = 0,778). No entanto, o sexo foi relacionado aos níveis de ansiedade (p < 0,001), com os homens em
nosso estudo sendo associados a níveis moderados e graves de sintomas de ansiedade. Conclusão: Concluiu-se
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Braz Dent Sci 2025 Apr/Jun;28 (2): e4501
Carvalho LLM et al.
Analysis of the relationship between anxiety symptoms and temporomandibular disorder in undergraduate dental students
Carvalho LLM et al. Analysis of the relationship between anxiety symptoms and
temporomandibular disorder in undergraduate dental students
que a ansiedade está associada à ocorrência de DTMs dolorosas em estudantes de odontologia, com níveis
moderados e graves de sintomas de ansiedade sendo mais prevalentes em indivíduos com DTM.
PALAVRAS-CHAVE
Ansiedade; Dor orofacial; Estudantes de Odontologia; Estresse; Síndrome da Disfunção da Articulação Temporomandibular.
INTRODUCTION
Temporomandibular disorders (TMDs) are
understood as a group of conditions affecting
the temporomandibular joint (TMJ), masticatory
muscles, and related structures. They are
recognized as the most prevalent cause of chronic
orofacial pain [1], considered as multifactorial,
with the involvement of a series of local and
systemic factors that, interacting with each
other. Among these, the psychological factor
has been investigated in a series of studies [1-3].
Psychological and social factors converge to form
a perception of health, which directly inuences
the behavior and emotional response to pain [4].
The clinical association between pain and
emotions, particularly negative ones such as
depression and anxiety, is well-established
in areas like medicine and psychology. More
recently, this relationship has garnered attention
in the realm of orofacial pain [1]. Recent research
indicates that individuals experiencing orofacial
pain exhibit higher levels of stress, depression,
anxiety, and nonspecific physical symptoms
compared to healthy controls [1,5,6].
Regardless of its origin, whether muscular
or articular, pain is the primary factor linking
TMD to the presence of anxiety symptoms [1].
Anxiety is characterized as a mood disorder
involving excessive worry about various activities
or events. Symptoms typically include agitation,
nervousness, easy fatigue, difculty concentrating,
irritability, muscle tension, and disrupted sleep,
all of which can significantly impact social
functioning [7]. Consequently, persistent and
uncontrolled pain establishes a vicious cycle of
anxiety and more pain [2].
Longitudinal studies [4,8] indicate that
disability due to pain, stress, depression,
and/or anxiety constitutes significant risk
factors contributing to the chronicity of TMDs.
Social factors further exacerbate this chronic
pain condition [4,8]. However, there are still
few studies focused on specific populations
exposed to high levels of learning tasks, facing
personal and professional uncertainties, such as
graduate students. Therefore, this study aims
to investigate whether the presence of anxiety
symptoms among undergraduate students
enrolled in the Dentistry program at the Federal
University of Juiz de Fora, Campus Governador
Valadares (UFJF-GV), is associated with the
occurrence of painful TMDs.
MATERIAL AND METHODS
In preparation for this study, prior to
implementing the methodology, the project
underwent ethical review by the Human Research
Ethics Committee of the Federal University of
Juiz de Fora (UFJF). The approval code for this
study is: 6.116.687.
Selection of participants
The students of the Dentistry course at UFJF-GV
were invited via e-mail to participate in the research.
Those who agreed to take part in it, signed a
document equivalent to a written informed consent
and, subsequently, answered the questionnaire and
underwent a clinical examination. The number of
total participants was 60.
The GAD-7 questionnaire (Generalized
Anxiety Disorder – 7) [9], included in the axis II
of the Diagnostic Criteria for Temporomandibular
Disorders (DC/TMD) [10], was used to verify
the anxiety symptom levels in this study. This
internationally validated tool has an official
Portuguese version. The questionnaire explored
general and oral health aspects, pain intensity
experienced (at the time of completion, in the last
6 months, and during the worst episode), and the
impact of pain on daily activities. It also addressed
interest in daily activities, negative emotional
experiences, and occurrences of anxiety, agitation,
and nervousness over the past two weeks.
Participants rated symptom frequency using the
options: “never,” “sometimes,” “more than half the
days,” and “nearly every day,” corresponding to
values of 0, 1, 2, and 3, respectively. Cumulative
scores categorized anxiety symptom levels as low
(>5), moderate (5-15), or high (>15), based on
the combined values selected by participants.
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Carvalho LLM et al.
Analysis of the relationship between anxiety symptoms and temporomandibular disorder in undergraduate dental students
Carvalho LLM et al. Analysis of the relationship between anxiety symptoms and
temporomandibular disorder in undergraduate dental students
Additionally, the axis I of the DC/TMD [10]
was employed to conduct the physical diagnosis
of painful TMDs. This was done to determine
whether participants had any form of TMD,
be it muscular, articular, or a combination of
both. Based on this assessment, individuals
were allocated into one of two research groups:
Control (Co), composed by students without a
TMD diagnosis, and Experimental (Exp), which
included students diagnosed with TMD according
to the DC/TMD.
Participants in this study were recruited
via email. The researchers requested the Board
of the Dentistry Department of UFJF-GV to
disseminate an invitation to all regularly students
to participate. Interested students responded by
emailing one of the researchers, whose contact
information was provided in the invitation. The
questionnaire application was made in person
at a convenient time for each participant in one
of the dental clinics of the university, ensuring
an adequate sample size. Participants were
required to sign a written informed consent
document prior to completing the questionnaire.
Upon completion, the questionnaires were
retained by the researchers, who upheld the
ethical standards of participant anonymity
and data confidentiality. The application of
the questionnaires and the examination was
conducted by a single calibrated examiner.
Participants eligible for this research were
students enrolled in the graduate dentistry
program at UFJF-GV, who were at least 18 years
of age at the commencement of the study.
Students currently undergoing treatment for
temporomandibular disorders (TMDs) and/
or anxiety disorders were excluded to prevent
confounding factors that could impact the
interpretation of the study’s results.
Participants were informed that they could
discontinue their participation at any time, even
after completing the questionnaire, should they
wish to do so. This discontinuation would not
require justification and would not result in
any personal repercussions. However, during
the study, no participants chose to discontinue
their participation
Analysis of the results
The data collected were recorded in Excel
spreadsheets (Excel, Office 16, Redmond,
Washington, USA) and subjected to descriptive
statistical analysis. The chi-square and Fisher’s
exact tests were performed using GraphPad Prism
is 10.2.1 software (Dotmatics, Eneld, London,
EN3 6XH, United Kingdom) to determine
whether there is an association between the
level of anxiety symptoms and the occurrence
of painful temporomandibular disorders (TMD)
in dental students
RESULTS
The sample consisted of 60 students of the
Dentistry program at UFJF-GV, with 18 (30%)
identifying as male and 42 (70%) as female.
30 participants were diagnosed with some painful
TMD. These cases were further classied into
three categories: muscular, articular, or combined
muscular/articular (Table I).
The application of the GAD-7 revealed that
27 participants exhibited no symptoms of anxiety.
Additionally, 7 participants displayed mild
anxiety symptoms, 18 demonstrated moderate
anxiety symptoms, and 8 presented with severe
anxiety symptoms (see Table II).
Following the statistical analysis of the data,
the chi-square test revealed a signicant association
between anxiety levels and the occurrence of
Table I - Prevalence of TMDs in the studied population
Co Exp
Muscular Articular Muscular/ Articular
30 13 6 11
Table II - Levels of anxiety symptoms among the study participants
NO ANXIETY SYMPTOMS ANXIETY SYMPTOMS
Mild Moderate Severe
Co 20 7 3 0
Exp 7 0 15 8
p- valor
< 0.001
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Carvalho LLM et al.
Analysis of the relationship between anxiety symptoms and temporomandibular disorder in undergraduate dental students
Carvalho LLM et al. Analysis of the relationship between anxiety symptoms and
temporomandibular disorder in undergraduate dental students
TMD (p < 0.001). Moderate and severe anxiety
symptoms were associated with a higher frequency
of TMD, whereas most participants without TMD
showed no symptoms of anxiety
However, no correlation was observed
between anxiety symptoms and the diagnosis of
a specic type of TMD over others (muscular,
articular, or muscular/articular) (p = 0.071).
Regarding sex, Fischer’s test indicated that
it does not inuence the occurrence of TMDs
(p = 0.778). However, an association with
the level of anxiety symptoms was observed
(p < 0.001; chi-square). In this study, most
women exhibited either no or low levels of
anxiety symptoms, whereas men were more
frequently associated with moderate to severe
anxiety symptoms (Table III).
DISCUSSION
TMDs are characterized as a diverse group
of clinical conditions that adversely impact
individuals’ emotional health. Psychosocial
factors are among the risk factors that can
perpetuate or even intensify pain symptoms.
Consequently, symptoms of anxiety, whether
transient or chronic psychological disorders,
have been extensively examined in the context
of TMDs. This is because psychological changes
often coexist with pain in the temporomandibular
region, creating an interplay between physical
and emotional symptoms [11,12]. In light of this,
the present study aimed to assess the relationship
between anxiety symptoms and TMDs among
undergraduate dental students at UFJF-GV.
In this study, a signicant association was
found between painful TMD and moderate
to severe anxiety symptoms. This indicates a
notable relationship between higher levels of
anxiety and the presence of TMD, consistent
with the ndings of Ton et al. [13]. According
to the literature, anxiety symptoms in the
student population can reach a prevalence of up
to 90% [14]. These symptoms may arise from
various stressors, including heavy workloads, the
pressure to achieve academic success, uncertain
future prospects, living away from family and
adapting to a new environment. Additionally,
students face social, emotional, physical, and
familial challenges [15,16]. These high levels of
anxiety are known to increase the activity of the
masticatory muscles, which can subsequently lead
to TMD, whether muscular or joint-related [17].
Although an intercontinental survey
conducted in 17 countries with 85,052 adults
shows a higher prevalence of TMD in women
(62%) compared to men (38%) [17] and
another study indicates similar results for
student populations (65% for women and 35%
for men) [18], the results of this study reveal
no signicant inuence of sex on the presence
of TMD, contrary to previous findings where
prevalence was higher among women. We
hypothesize that this lack of sex-based inuence
may be related to the study group, which consists
of students with a similar age range and in the
same academic context, even though they are
at different stages of their courses, factors that
may contribute to a more homogeneous sample.
However, current literature suggests that the
high prevalence of TMDs in women, with onset
patterns after puberty and lower prevalence
rates postmenopause, indicates that female
reproductive hormones, such as uctuations in
estrogen levels, play a crucial etiological and
physiological role in altering pain thresholds and
the development of these conditions [19].
The current results indicate that men in this
sample experienced moderate to severe anxiety
symptoms more frequently than women, which
might explain why they were diagnosed with
TMD more often than their female counterparts.
However, these ndings are inconsistent with
previous studies, which have reported a higher
prevalence of these symptoms among women
[20-22]. The higher prevalence of severe anxiety
Table III - Relationship of TMD and levels of anxiety symptoms with sex of the study volunteers
SEX TMD ANXIETY SYMPTOMS
Absent Present Absent Mild Moderate Severe
Women 22 20 26 7 8 1
Men 8 10 1 0 10 7
p-valor
0.778 <0.001
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Analysis of the relationship between anxiety symptoms and temporomandibular disorder in undergraduate dental students
Carvalho LLM et al. Analysis of the relationship between anxiety symptoms and
temporomandibular disorder in undergraduate dental students
symptoms in men in the present study may be
related to different coping mechanisms between
genders, as suggested by Sójka et al. [23].
Women might be more proactive in confronting
challenges and therefore invest more effort in
problem-solving or managing stress, potentially
reducing their anxiety symptoms [22].
Therefore, the results of this study should be
interpreted with caution due to several limitations.
Firstly, the small sample size limits the ability to
quantify the extent to which anxiety symptoms are
associated with TMD occurrence. Specically, the
study does not provide statistical evidence on how
variations in anxiety levels affect the likelihood of a
TMD diagnosis. Secondly, the study was conducted
exclusively among university students enrolled in
the Dentistry program at UFJF-GV, encompassing
students from both the introductory and advanced
stages of the dental program. It remains uncertain
whether these ndings can be generalized to other
elds or populations. Further research is needed
to validate these results. Ultimately, a larger and
more representative sample of university students
is essential for drawing more denitive conclusions.
CONCLUSION
The results of this study indicated that
anxiety was associated with the occurrence of
painful temporomandibular disorders (TMDs)
in Dentistry graduate students at UFJF-GV.
Furthermore, medium to high levels of anxiety
symptoms were more prevalent among individuals
with TMD compared to those in the control group
without TMD.
Acknowledgements
Thanks, are extended to the Pro-Rectory of
Postgraduate Studies at the Federal University
of Juiz de Fora for recognizing this research.
The study was conducted voluntarily by the
researchers without external funding. The support
and recognition provided by the institution have
been invaluable for advancing the work.
Author’s Contributions
LLMC: Conceptualization, Methodology,
Software, Validation, Formal Analysis,
Investigation, Resources, Data Curation, Writing
– Original Draft Preparation, Writing – Review &
Editing, Visualization and Project Administration.
IC: Writing – Original Draft Preparation and Writing
Review & Editing. AATC: Methodology and Writing
Review & Editing. RLAC: Conceptualization,
Methodology, Software, Validation, Formal
Analysis, Investigation, Resources and Supervision.
JSM: Conceptualization, Methodology, Software,
Validation, Formal Analysis, Investigation,
Resources, Data Curation, Writing – Original
Draft Preparation, Writing – Review & Editing,
Project Administration Funding Acquisition and
Supervision.
Conict of Interest
The authors have no conicts of interest
to declare.
Funding
The authors declare that no nancial support
was received.
Regulatory Statement
This study was conducted in accordance with
all the provisions of the local human subjects’
oversight committee guidelines and policies of
Human Ethics and Research Committee of the
Federal University of Juiz de Fora. The approval
code for this study is: 6.116.687.
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Carvalho LLM et al.
Analysis of the relationship between anxiety symptoms and temporomandibular disorder in undergraduate dental students
Carvalho LLM et al. Analysis of the relationship between anxiety symptoms and
temporomandibular disorder in undergraduate dental students
Date submitted: 2024 Aug 27
Accept submission: 2025 May 08
Jean Soares Miranda
(Corresponding address)
Departamento de Odontologia, Universidade Federal de Juiz de Fora, campus
Governador Valadares, Governador Valadares - MG, Brazil.
Email: jean.miranda@ufjf.br
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