Affective relationships as predictors of TMD symptoms in young adults

Relações afetivas como preditoras de sintomas de DTM em adultos jovens

Abstract

Introduction

Orofacial pain is a critical TMD symptom that can influence physical and social capacity.

Objective

To evaluate the association of temporomandibular disorders (TMD) symptoms with affective relationships and demographic variables in young adults.

Material and method

A cross-sectional study involving 395 young adults was developed. Diagnostic Criteria for TMD, anxiety, and depression were collected from questionnaires. The Dental Health Component of the Index of Orthodontic Treatment Need measures the orthodontic treatment need. Questionnaires also contained questions related to the previous orthodontic treatment. Logistic regression models were adjusted, estimating crude odds ratio with the 95% confidence intervals. The variables with p<0.20 in the analyses were assessed in a multiple logistic regression model, remaining with p≤0.10.

Result

There was no significant association of TMD symptoms with sex, age, medication use for pain, previous orthodontic treatment, orthodontic treatment need, anxiety, and depression (p>0.05). Individuals without an affective relationship are 1.78 (95%CI: 0.99-3.17) times more likely to report TMD symptoms.

Conclusion

Affective relationships showed an association with TMD symptoms in young adults.

Descriptors:
Malocclusion; anxiety and depression; temporomandibular disorder; young adult; woman

Resumo

Introdução

A dor orofacial é um sintoma crítico da DTM que pode influenciar a capacidade física e social.

Objetivo

Avaliar a associação dos sintomas das desordens têmporomandibulares (DTM) com as relações afetivas e variáveis demográficas em adultos jovens.

Material e método

Estudo transversal envolvendo 395 adultos jovens foi realizado. Os critérios diagnósticos para DTM, ansiedade e depressão foram coletados a partir de questionários. O Componente de Saúde Bucal do Índice de Necessidade de Tratamento Ortodôntico mensurou a necessidade de tratamento ortodôntico. Os questionários também continham questões relacionadas ao tratamento ortodôntico anterior. Modelos de regressão logística foram ajustados, estimando odds ratio bruto com os intervalos de confiança de 95%. As variáveis com p<0.20 nas análises foram avaliadas em modelo de regressão logística múltipla, permanecendo as variáveis com p≤0.10.

Resultado

Não houve associação significativa dos sintomas de DTM com sexo, idade, uso de medicamentos para dor, tratamento ortodôntico prévio, necessidade de tratamento ortodôntico, ansiedade e depressão (p>0.05). Indivíduos sem relacionamento afetivo têm 1.78 (IC95%:0.99-3.17) vezes mais chance de relatar sintomas de DTM.

Conclusão

Os relacionamentos afetivos mostraram associação com os sintomas de DTM em adultos jovens.

Descritores:
Má oclusão; ansiedade e depressão; desordem temporomandibular; jovem adulto; mulher

INTRODUCTION

Orofacial pain may have social, psychological, and economic consequences on individuals and communities¹. When untreated, it may lead to disability, increased risk of depression, sleep deprivation, reduced quality of life, and social isolation².

The prevalence of orofacial pain in the population is around 10% to 15%³, and it is one of the main temporomandibular disorder (TMD) symptoms¹. Individual with TMD may present several changes in the stomatognathic system caused by tooth wear, malocclusion, previous orthodontic treatment, inflammatory and infectious processes, trauma, stress, anxiety, and other psychogenic factors⁴. This strengthens the hypothesis that psychological disorders and psychosocial impairments are highly prevalent in TMD patients⁵ and may lead to increased muscle hyperactivity⁶. Hence, TMD refer to conditions affecting mastication and/or temporomandibular joint (TMJ) muscles, which are indicated as the leading cause of non-dental pain in the orofacial region, including head, face, and related structures.

Studies have suggested that symptoms related to TMD occur predominantly in young adults and women in a female: male ratio of 4:1^7,8. Moreover, this condition is more prevalent among women in their reproductive years - between 20 and 40 years old -, which are attributed to stress, social and cultural behavior, and effects related to hormonal characteristics^7,9.

Despite the great number of studies investigating this association, such an issue remains controversial¹⁰. The current evidence suggests that TMD should be seen as a group of diseases with solid genetic factors and psychosocial aspects, which play a significant role in its incidence¹¹. In addition, it is known that TMD may result from the interrelation of psych behavioral, occlusal, and neuromuscular factors. Thus, understanding the origin and characteristics of this disorder and planning the respective treatment is significant for understanding TMD¹².

There is no report in the literature regarding the impact of affective relationships on the TMD symptoms among predisposing factors. However, considering the importance of psych behavioral aspects in TMD etiology, the stable union of couples provides a sort of stability in the sentimental context, consequently decreasing TMD symptoms¹².

Considering the population of young adults and the multifactorial character of TMD, the hypothesis studied is that affective relationships influence TMD symptoms among young adults. Thus, the main objective was to evaluate the association of TMD symptoms with affective relationships and demographic variables in young adults.

MATERIAL AND METHOD

Experimental Design

The Research Ethics Committee approved this cross-sectional study (# 2.324.935/2017). The participation was voluntary, and all subjects were informed about the examination procedures, and the confidentiality of the information collected was guaranteed. The subjects who agreed with their participation signed the free and informed consent form at the beginning of the study, produced according to the STROBE statement.

The minimum sample of 350 individuals was determined based on a previous pilot study (n = 50) in the Epi info software (Centers for Disease Control and Prevention, Atlanta, GA, USA), considering a significance level of 5%, power 80% Test and Effect Size 2.0. A simple probabilistic sampling procedure recruited randomly selected subjects within the target age group (20 to 30 years of age). Individuals with current or previous orthodontic treatment and a history of craniofacial fracture and orthognathic surgery were excluded from the study. The final sample included the participation of 395 young adults with an average age of 22 years. The study was carried out between March and June 2018.

The outcome was the presence of temporomandibular disorder (TMD) symptoms. The independent variables were classified into demographic (e.g., gender, age, marital status, children), use of medication for continuous and/or sporadic pain, orthodontic characteristics (e.g., current or previous orthodontic treatment need), and anxiety and depression. The “affective relationship” was considered when individuals reported dating, marriage, or stable union.

TMD Symptoms

The Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) is an instrument used to evaluate an individual’s TMD symptoms¹³. The assessment consists of 14 items related to pain, headache, TMJ noise, open- and closed-mouth jaw locking. The responses are binomial (yes/no). In this study, if the individual answered yes to any of the questions, TMD symptom was considered.

Anxiety and Depression

The Hospital Anxiety and Depression Scale (HADS)¹⁴ was used to identify and measure the intensity of anxiety and depression. HADS consists of 14 items divided into two scales, in which seven items measure anxiety (HADS-A) and seven others measure depression (HADS-D). The anxiety and depression evaluated are separated, and each item is classified from 0 to 3, depending on the response. The maximum score is 21 points for each scale, as follows: scores from 0 to 7 absence of anxiety or depression, 8 to 10 potential anxiety or depression, and above 11 the presence of anxiety or depression¹⁵. The version used was validated for the Portuguese language¹⁶.

Orthodontic Treatment Need

All individuals had their occlusal clinical condition assessed using the Index of Orthodontic Treatment Need (IOTN)¹⁷. For the clinical examination, the examiner, using all personal protective equipment, used a disposable lip retractor, flashlight, and WHO 621 clinical periodontal probe (Campo Mourão, PA, Brazil), with the individuals seated in an environment with natural light. Only the most severe occlusal change served as a base for classifying the treatment need of individuals¹⁷. The index determined the orthodontic treatment need (levels 1 through 5) of individuals. For data analysis, levels from 1 to 3 were classified as no need for orthodontic intervention, and levels from 4 to 5 represented treatment need.

Training and Calibration Exercise

Clinical examinations were performed by a single calibrated examiner, who participated in theoretical training exercises and clinical calibration based on the criteria proposed by the index. Theoretical training for the requirements evaluated by the IOTN was carried out in plaster models to discuss the clinical characteristics of each condition evaluated. For clinical calibration, the researcher examined 20 subjects who did not participate in the primary study sample separately to determine intra-examiner agreement. The Kappa coefficient exceeded 0.92 for the assessment of malocclusion.

Statistical Analysis

Simple logistic regression models were adjusted to each independent variable and the outcome variable of the presence of TMD, estimating crude odds ratio with the 95% confidence intervals. The variables with p<0.20 in the crude analyses were investigated in a multiple logistic regression model, remaining in the variables with p≤0.10. The associations between each TMD symptom and the variables studies were also assessed using the Chi-square test. The analyses were performed in the R software (R Foundation for Statistical Computing, Vienna, Austria) at a 5% significance level.

RESULT

A total of 395 young adults with a mean age of 22 years (± 3.3) participated in this study. Demographic, use of medication for continuous and/or sporadic pain, orthodontic characteristics, anxiety, depression, and TMD symptoms data are presented in Table 1.

Table 1
Associations between the TMD and the variables studied

Variable	Categories	n(%)	TMD		$Crude OR (#95%CI)	p-value	$Final model OR	p-value
			Absence	Presence*			(#95%CI)
			n (%)	n (%)
Gender	Male	103 (26.1)	23 (22.3)	80 (77.7)	Ref
	Female	292 (73.9)	60 (20.6)	232 (79.4)	1.11 (0.64-1.92)	0.7028
Age	≤22 years (median)	211 (53.4)	38 (18.0)	173 (82.0)	1.47 (0.91-2.40)	0.1178
	>22 years (median)	184 (46.6)	45 (24.5)	139 (75.5)	Ref
Affective	No	324 (82.0)	62 (19.1)	262 (80.9)	1.78 (0.99-3.17)	0.0525	1.78 (0.99-3.17)	0.0525
relationship	Yes	71 (18.0)	21 (29.6)	50 (70.4)	Ref		Ref
Children	No	321 (81.3)	63 (19.6)	258 (80.4)	1.52 (0.85-2.72)	0.1606
	Yes	74 (18.7)	20 (27.0)	54 (73.0)	Ref
Medication use for	No	312 (79.0)	70 (24.4)	242 (77.6)	Ref
orofacial pain	Yes	83 (21.0)	13 (15.7)	70 (84.3)	1.56 (0.81-2.98)	0.1808
Previous orthodontic	No	123 (31.1)	24 (19.5)	99 (80.5)	Ref
treatment	Yes	272 (68.9)	59 (21.7)	213 (78.3)	0.88 (0.52-1.49)	0.6227
Orthodontic	No need (1-3)	339 (85.8)	69 (20.4)	270 (79.6)	Ref
Treatment need	With need (>3)	56 (14.2)	14 (25.0)	42 (75.0)	0.77 (0.40-1.48)	0.4301
Anxiety	No (HADS A≤10)	272 (68.9)	59 (21.7)	213 (78.3)	Ref
	Yes (HADS A>10)	123 (31.1)	24 (19.5)	99 (80.5)	1.14 (0.67-1.94)	0.6227
Depression	No (HADS D≤10)	348 (88.1)	73 (21.0)	275 (79.0)	Ref
	Yes (HADS D>10)	47 (11.9)	10 (21.3)	37 (78.7)	0.98 (0.47-2.07)	0.9621

• ^*
  Reference category for the outcome variable. ^$Odds ratio. ^#Confidence interval.

Table 1 also shows the associations between TMD (yes/no), and the variables studied. There was no significant association of TMD symptoms with gender, age, presence of children, medication use for pain, previous orthodontic treatment, orthodontic treatment need, anxiety, and depression (p>0.05). However, individuals who reported no affective relationship are 1.78 (95%CI: 0.99-3.17) times more likely to present some TMD symptom.

Table 2 presents the associations between TMD symptoms and the variables studied. There is a higher frequency of individuals with closed-mouth jaw locking among those using medication for pain (p<0.05). There was also a higher rate of open-mouth jaw locking among those with children and treatment needs.

Table 2
Associations between TMD symptoms and the variables studied

Variable	Categories	Presence of facial pain	p-value	Presence of headache	p-value	Presence of noise	p-value	Presence of	p-value	Presence of	p-value
								closed-mouth		open-mouth
								jaw locking		jaw locking
		n (%*)		n (%)		n (%)		n (%)		n (%)
Sex	Male	56 (54.4)	0.2677	49 (47.6)	0.6784	48 (46.6)	0.2008	35 (34.0)	0.1406	13 (12.6)	0.5108
	Female	177 (60.6)		132 (45.2)		115 (39.4)		77 (26.4)		30 (10.3)
Age	≤22 years	127 (60.2)	0.6029	98 (46.4)	0.7902	83 (39.3)	0.4042	60 (28.4)	0.9693	22 (10.4)	0.7535
	>22 years	106 (57.6)		83 (45.1)		80 (43.5)		52 (28.3)		21 (11.4)
Affective	Yes	40 (56.3)	0.6163	28 (39.4)	0.2331	25 (35.2)	0.2525	21 (29.6)	0.8007	9 (12.7)	0.5929
relationship	Not married	193 (59.6)		153 (47.2)		138 (42.6)		91 (28.1)		34 (10.5)
Children	No	193 (60.1)	0.3385	151 (47.0)	0.3117	132 (41.1)	0.9032	88 (27.4)	0.3879	30 (9.4)	0.0407
	Yes	40 (54.0)		30 (40.5)		31 (41.9)		24 (32.4)		13 (17.6)
Medication use for	No	181 (58.0)	0.4452	142 (45.5)	0.8105	130 (41.7)	0.7537	81 (26.0)	0.0408	30 (9.6)	0.1159
pain	Yes	52 (62.6)		39 (47.0)		33 (39.8)		31 (37.4)		13 (15.7)
Previous orthodontic	No	76 (61.8)	0.4466	63 (51.2)	0.1477	54 (43.9)	0.4741	35 (28.5)	0.9761	14 (11.4)	0.8314
treatment	Yes	157 (57.7)		118 (43.4)		109 (40.1)		77 (28.3)		29 (10.7)
Orthodontic	No need	199 (58.7)	0.7767	154 (45.4)	0.6982	136 (40.1)	0.2542	93 (27.4)	0.3178	32 (9.4)	0.0231
treatment need	With need	34 (60.7)		27 (48.2)		27 (48.2)		19 (33.9)		11 (19.6)
Anxiety	No	155 (57.0)	0.2290	128 (47.1)	0.4634	113 (41.5)	0.8673	71 (26.1)	0.1398	30 (11.0)	0.8918
	Yes	79 (63.4)		53 (43.1)		50 (40.6)		41 (33.3)		13 (10.6)
Depression	No	206 (59.2)	0.8191	162 (46.6)	0.4288	140 (40.2)	0.2551	97 (27.9)	0.5640	36 (10.3)	0.3473
	Yes	27 (57.4)		19 (40.4)		23 (48.9)		15 (31.9)		7 (14.9)

• ^*
  Percentage with presence in each category.

DISCUSSION

This cross-sectional study assessed the impact of the affective relationship on TMD symptoms among young adults. According to the World Health Organization¹⁸, young adults have considered individuals aged 20 through 40 years. The highest prevalence of TMD symptoms is observed in young women in an age group attributed to stress, social and cultural behavior, and hormonal characteristics^7,9,19. Therefore, this study included a sample of volunteers aged 20 through 30 years to eliminate age as a confounding factor.

The results showed that affective relationships in adult life might be associated with the reporting of TMD symptoms, and we highlight that the previous literature has no information on such association. However, affective relationships are essential within the emotional context of individuals and deserve attention because they are inseparable from human development. The present study showed that individuals without a stable affective relationship are more likely to report TMD symptoms, but the association needs to be better understood.

The sociodemographic variables such as gender and age group did not affect TMD symptoms, corroborating with previous studies^20,21. As for sexual dimorphism, the literature shows different results^22,23, because women present more TMD symptoms than men. The hypothesis for such difference potentially refers to the age group of the sample studied, and the method applied. The present study was careful to include the age group most affected by TMD, between 20 and 30. In Oberoi et al.²² study the age group ranged between 30 and 65 years and Ferreira et al²³. assessed individuals between 19 and 40. Moreover, the sample by Ferreira et al.²³ was considered convenient because it was taken from medical records, leaving the uncertainty of whether women present more pain or whether men may present the same frequency and incidence of pain without having sought care.

In the present study, few individuals reported using some medication for controlling orofacial pain continuously or sporadically, but almost all individuals presented some TMD symptoms. Thus, it is suggested⁴ the need for investigating comorbidity factors in TMD patients to determine the best treatment strategy. The sensitization of the central nervous system is an amplification of the neural signaling that induces hyperalgesia, in which pain may not be controlled with peripheral action therapy but instead with medications that work on the central nervous system⁴.

Among the individuals assessed, 68.9% reported having been subjected to previous orthodontic treatment, from which 78.3% presented some TMD symptom, but without statistical significance. This finding corroborates a previous study¹⁰, which did not identify such an association even though many orthodontic patients with TMD symptoms were observed. According to current systematic reviews^11,24, the literature does not report the association between TMD and occlusion, suggesting that orthodontics neither causes nor cures TMD, but it also does not prevent the further development of the disorder. Moreover, it is known that invasive dental therapies such as orthodontic treatment are not recommended for either treating or preventing TMD²⁵.

The findings of this study showed that anxiety and depression did not affect the report of TMD symptoms. However, 31.1% of the sample presented anxiety, and some individuals with anxiety (80.5%) reported TMD symptoms. Likewise, 11.9% of individuals had depression, of which 78.7% had some TMD symptoms. Previous studies correlated comorbidities, such as anxiety and depression, and other psychological factors to TMD^1,4,9, which was the reason for studying such variables. Psychosocial factors, somatization, depression, and catastrophization represent risk factors for the long-term persistence of TMD⁴.

As for the limitations, the cross-sectional study design prevents the establishment of a cause-and-effect relationship. Furthermore, no scale was used to measure anxiety and stress in the present study, which can be considered a limitation, but future studies integrating this characterization should be developed. A longitudinal study is suggested to assess the influence of variables on TMD symptoms over time.

In general, psychosocial and sociodemographic factors may be associated with TMD symptoms to some extent. Therefore, it is essential to assess the risk factors correlated with TMD to reduce discomfort and improve the quality of life of individuals and guide the treatment strategy for TMD symptoms.

CONCLUSION

In conclusion, affective relationships showed an association with TMD symptoms in young adults.

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  Sousa ST, de Mello VVC, Magalhães BG, Morais MPLA, Vasconcelos MMVB, Caldas AF Jr, et al. The role of occlusal factors on the occurrence of temporomandibular disorders. Cranio. 2015 Jul;33(3):211-6. http://dx.doi.org/10.1179/2151090314Y.0000000015 PMid:25027731.
  » http://dx.doi.org/10.1179/2151090314Y.0000000015

Publication Dates

• Publication in this collection
  20 Sept 2021
• Date of issue
  2021

History

• Received
  24 Mar 2021
• Accepted
  12 Aug 2021