BACKGROUND AND OBJECTIVES:
The aim of the present study was to evaluate the impact of the COVID-19 pandemic on psychological aspects and its relationship with bruxism from a representative sample of the Brazilian population.
A cross-sectional Internet-based survey was conducted in a nationally representative sample of Brazilian adults to estimate the sociodemographic correlates and characteristics of bruxism, the quality of life of individuals World Health Organization Quality of Life-BREF (WHOQOL) and Self-Compassion Scale (SCS) in the Brazilian population during the COVID-19 pandemic. Research was collected from May to August 2020. The data were analyzed using qualitative analysis.
A total of 1476 Survey forms were completed, and 1265 (85.70%) respondents declared presenting daytime clenching; over half of respondents (843, 57.11%) reported that they have grinding of teeth; and 1054 (71.41%) reported both clenching and grinding of teeth. Most of the respondents (1128, 76.42%) reported a negative perception of oral symptoms on the last month and all (1476, 100.00%) were feeling nervous or stressed during the period of social withdrawal induced by the COVID-19 pandemic. Moreover, 289 (19.58%) started having symptoms of fatigue or pain in the muscles of the face upon awakening and 318 (21.54%) started having muscle fatigue and discomfort in the teeth upon awakening.
Findings have shown that all respondents were feeling nervous or stressed during the period of social withdrawal induced by the COVID-19 pandemic and reported bruxism symptoms. They also had lower averages of WHOQOL and SCS, suggesting worse perception of quality of life and self-compassion.
Bruxism; Coronavirus Infections; Quality of Life
JUSTIFICATIVA E OBJETIVOS:
O objetivo do presente estudo foi avaliar o impacto da pandemia de COVID-19 nos aspectos psicológicos e sua relação com o bruxismo a partir de amostra representativa da população brasileira.
Foi conduzida uma pesquisa transversal baseada na internet em uma amostra representativa de adultos brasileiros para estimar os correlatos sociodemográficos e as características do bruxismo, a qualidade de vida (WHOQOL) dos indivíduos e a autocompaixão (SCS) na população brasileira durante a pandemia por COVID-19. A pesquisa foi coletada de maio a agosto de 2020. Os dados foram analisados por meio de análise qualitativa.
Foram preenchidos 1.476 formulários da Pesquisa e 1.265 (85,70%) respondentes declararam apresentar apertamento diurno; mais da metade dos entrevistados (843, 57,11%) relatou ranger de dentes; e 1.054 (71,41%) relataram tanto apertamento quanto ranger de dentes. A maioria dos entrevistados (1.128, 76,42%) relatou percepção negativa dos sintomas de bruxismo no último mês e todos (1.476, 100,00%) estavam se sentindo nervosos ou estressados durante o período de afastamento social induzido pela pandemia de COVID-19. Além disso, 289 (19,58%) iniciaram sintomas de fadiga ou dor nos músculos da face ao acordar e 318 (21,54%) iniciaram com fadiga muscular e desconforto nos dentes ao acordar.
Os resultados mostraram que todos os entrevistados estavam se sentindo nervosos ou estressados durante o período de afastamento social induzido pela pandemia de COVID-19 e relataram sintomas de bruxismo. Também apresentaram médias mais baixas no WHOQOL e SCS, sugerindo pior percepção de qualidade de vida e autocompaixão.
Infecções por coronavírus; Bruxismo; Qualidade de vida
The temporomandibular joint (TMJ) is formed by the articulation of the mandible and the temporal bone of the cranium. It is located anteriorly to the tragus of the ear, on the lateral aspect of the face and it’s the most regularly used joint in the human body, opening and closing 1,500 to 2,000 times a day, to perform the various necessary movements11 Chang CL, Wang DH, Yang MC, Hsu WE, Hsu ML. Functional disorders of the temporomandibular joints: Internal derangement of the temporomandibular joint. Kaohsiung J Med Sci. 2018;34(4):223-30..
Motor functions, as well as suction and maintenance of the mandibular posture of the masticatory system are considered classic. Adaptive motor functions are yawning, kissing, biting, blowing, laughing, and grinding teeth22 Murali RV, Rangarajan P, Mounissamy A. Bruxism: Conceptual discussion and review. J Pharm Bioallied Sci. 2015;7(Suppl 1):S265-70..
Muscles present in this region are responsible for lifting or closing movements, depression or opening, protrusion and retrusion and for alternating lateral movements, in addition to ensuring joint stability33 Celic R, Jerolimov V, Knezovic Zlataric D. Relationship of slightly limited mandibular movements to temporomandibular disorders. Braz Dental J. 2004;15(2):151-4..
Parafunctional habits like clenching and/or grinding your teeth during the day and/or at night, chewing gum, biting your cheek, lips, and tongue, pressing the tongue against the teeth, biting nails/cuticle, gnawing on objects like pencils/ pens or others, and placing the hand under the chin, are among the main etiological factors for temporomandibular disorders (TMD), as they promote and increase muscle activity above the necessary (muscle hyperactivity)44 Paulino MR, Moreira VG, Lemos GA, Silva PLPD, Bonan PRF, Batista AUD. Prevalence of signs and symptoms of temporomandibular disorders in college preparatory students: associations with emotional factors, parafunctional habits, and impact on quality of life. Cien Saude Colet. 2018;23(1):173-86..
For psychiatrists, the facial and jaw muscles are responsible for the expressions of anger, fear and aggression and for smiling. The clenching of teeth, bites on the cheeks, tongue, lips and objects, sucking on fingers and biting nails, have a well-defined emotional background and serve as a discharge of tension55 Fernandes G, Franco-Micheloni AL, Siqueira JT, Gonçalves DA, Camparis CM. Parafunctional habits are associated cumulatively to painful temporomandibular disorders in adolescents. Braz Oral Res. 2016;30:S1806-83242016000100214..
Epidemiological studies show that 5 to 6% of the world population will experience a painful experience involving the TMJ during their lives66 Oliveira W. Disfunções temporomandibulares. São Paulo: Artes Médicas; 2002. and the questionnaire application is widely used in research and is an important tool to identify population profiles, however, in some cases the sample number may become slightly reduced due to the need for time to apply the questionnaire and the territorial limitation. The online questionnaire has the advantage of greater reach considering the scope of the internet and the quarantine period77 Medeiros RA, Vieira DL, Silva EVFD, Rezende LVML, Santos RWD, Tabata LF. Prevalence of symptoms of temporomandibular disorders, oral behaviors, anxiety, and depression in Dentistry students during the period of social isolation due to COVID-19. J Appl Oral Sci. 2020;28:e20200445..
At the end of 2019, the New Coronavirus was named SARS-CoV-2. This New Coronavirus produced the disease classified as COVID-19, causing a series of pneumonia cases in the city of Wuhan (China). There is still no full information about the natural history, nor unquestionable effectiveness measures for the clinical management of cases of human infection by SARS-CoV-2, and there are still many details to be clarified. However, it’s known that the virus has high transmissibility and causes an acute respiratory syndrome that varies from mild cases - about 80% - to very severe cases with respiratory failure - between 5 and 10% of cases. Its lethality varies, mainly according to the age group and associated clinical conditions88 McIntosh K. Novel Coronavirus (2019-nCov). UpToDate, Post TW (Ed), UpToDate, Waltham, MA; 2020..
Therefore, the present study aims to assess the impact of the COVID-19 pandemic on psychological aspects and bruxism from a representative sample of the Brazilian population.
STROBE Statement was used for reporting this observational study99 von Elm E, Altman DG, Egger M, Pocock SJ, Gotzsche PC, Vandenbroucke J P. Strengthening the reporting of observational studies in epidemiology (STROBE) statement: guidelines for reporting observational studies. BMJ. 2014;12(12):1495-9.. This is a cross-sectional internet-based survey research. The survey was conducted from May to August 2020 by using an electronic questionnaire on Google Forms™ platform. Adults aged 18 years old, or more were eligible to participate.
Participants first answered a sociodemographic survey followed by specific questions about TMJ pain and parafunctional oral habits during the COVID-19 pandemic. The questionnaire included 14 questions in Portuguese in sequence, (1) Gender, (2) Age, (3) Race, (4) Schooling level, (5) Marital status, (6) Household income, (7) Region, (8) Employment status, (9) Internet access, (10) Metropolitan area.
After answering the sociodemographic survey questions, the individuals were asked about (11) daytime clenching; (12) daytime grinding of teeth; (13) both daytime clenching and grinding of teeth; (14) sounds of clenching or grating teeth while sleeping, noticed by a sleeping partner; (15) fatigue in jaw muscles in the morning; (16) headache, shoulder, neck and facial pain frequently; (17) clicking sound or grating sensation when opening the mouth; (18) discomfort in jaw in the morning; (19) history of tooth restoration/fractures; (20) self-perception of tooth wear; (21) ear or behind ear pain; and (22) locked jaw in the morning or during sleep.
Moreover, the participants were asked if they noted, in the current period on the last month of social isolation due to the COVID-19 pandemic, if the following conditions started happening: (23) fatigue or pain in the muscles of the face upon awakening; and (24) muscle fatigue and discomfort in teeth upon awakening. According to study1010 Raphael KG, Sirois DA, Janal MN, Wigren PE, Dubrovsky B, Nemelivsky LV, et al. Sleep bruxism and myofascial temporomandibular disorders: a laboratory-based polysomnographic investigation. J Am Dent Assoc. 2012;143(11):1223-31., bruxism is present if one of the items is answered “yes”.
The questionnaire also included 26 questions of the Self-Compassion Scale (SCS)1111 Nef KD, Bluth K, Tóth-Király I, Davidson O, Knox MC, Williamson Z, et al. Development and validation of the self-compassion scale for youth. J Pers Assess. 2021;103(1):92-105., which assesses trait levels of self-compassion. The scale was developed to explicitly represent the thoughts, emotions, and behaviors associated with the various components of self-compassion. It includes items that measure how often people respond to feelings of inadequacy or sufering with self-kindness, self-judgment, common humanity, isolation, mindfulness, and over-identification.
The sequence of questions included the World Health Organization Quality of Life-BREF (WHOQOL-bref) used to assess quality of life (QoL), with 26 questions, two of which were about QoL in general (general QoL) and the others represent each of the 24 facets that make up the original instrument and are divided into four domains: “physical”, “psychological”, “social relationships” and “environment”. Scores for each domain were transformed on a scale from zero to 100 and expressed in terms of averages, as recommended by the manual produced by the WHOQOL1212 The World Health Organization Quality of Life assessment (WHOQOL): position paper from the World Health Organization. Soc Sci Med. 1995;41(10):1403-9., with higher averages suggesting better perception of QoL.
Before answering the questionnaire, participants read and accepted the participant consent form Free and Informed Consent Term (FICT), which explained the objective and nature of the study and showed they could refuse to answer any questions and withdraw at any time from the research. The questionnaire was structured as an electronic questionnaire at Google Forms™, with no open questions and with preceded alternative answers.
To reduce the risk of bias, all data, which was accessed and extracted from Google Forms™, was analyzed by two investigators. The final tabulated database was analyzed by other two investigators.
The following data were extracted for the five macro-regions of Brazil (southern, south-eastern, northern, northeastern, central-western) in a convenience manner. The questionnaire was sent to the participants via general social media as well as through electronic messages from dentists, physicians, physical therapists and the Brazilian Dental Association. The total study size was all completed, with answers from May to August 2020.
This study was approved by the Ethics Committee on Human Research of the Federal University of Alfenas (CAAE: 30830420.7.0000.5142).
Descriptive statistics were used as the data analysis method. Questionnaire responses were entered into the Microsoft Excel software. Categorical data are represented as a percentage and SCS and WHOQOL-bref average scores were presented by mean, standard deviation (SD), coefficient of variation, maximal and minimal values, and amplitude (diference between maximum and minimum values).
Survey forms were completed by 1476 individuals. Among the respondents, 846 (57.32%) were men and 630 (42.68%) were women. Nearly half of the respondents (633) were 18-24 years old (42.90%); 211 (14.30%) were 25-34 years; 422 (28.60%) were 35-44 years; 90 (6.12%) were 45-54 years; and only 78 (5.28%) and 41 (2.80%) were 55–64 and 65 or older, respectively. According to the ethnic data collection, 792 (50.66%) were white, 466 (30.22%) were brown, 234 (15.85%) were black, less than 1% were yellow (4, 0.27%) and none were indigenous (Table 1).
Sociodemographic characteristics of the study sample (n=1476)
A vast majority of respondents had some college or bachelor’s degree or higher education, 754 (51.08%) and 667 (45.19%), respectively. Only 41 (2.78%) had high school level and 14 (0.95%) had less than high school level. As for marital status, 805 (54.54%) had never married; 364 (24.66%) were married; 278 (18.83%) were living with a partner and only 29 (1.96%) were divorced. Regarding household income, 574 (38.89%) had household income level less than R$999 a month and 459 (31.10%) had between R$2000 to R$4999; 265 (17.95%) had R$1000 to R$1999 and 178 (12.06%) had R$5000 or more.
From 1476 respondents, 893 (60.50%) were from the Southeast region of Brazil; 352 (23.85%) from the South; 181 (12.26%) from the Midwest and only 38 (2.57%) and 12 (0.81%) from the Northeast and North, respectively.
Additionally, 437 (29.61%) were not working - on temporary layof; 339 (22.97%) were students; 289 (19.58%) and 269 (18.22%) were working (as a paid employee or self-employed, respectively); and only 121 (8.20%) and 21 (1.42%) were retired or disabled, respectively. All participants had internet access, 682 (46.21%) were living in metropolitan areas and 788 (53.39%) in non-metropolitan areas.
Of 1476 respondents, 1265 (85.70%) declared having daytime clenching; over half of respondents (843, 57.11%) reported grinding of teeth; and 1054 (71.41%) reported both clenching and grinding of teeth. More than half of respondents (812, 55.01%) declared that a sleeping partner noticed that they were making sounds of clenching or grating teeth while sleeping. All respondents reported fatigue in jaw muscles in the morning and headache, shoulder, neck, and facial pain frequently.
Moreover, a vast majority of respondents had clicking sound or grating sensation when opening their mouth or chewing; discomfort in the jaw in the morning; and ear or behind ear pain (1266, 85.77%; 1160, 78.59%; and 933, 63.21% respectively). Over half of respondents (843, 57.11%) reported history of tooth restoration/fractures; but indicated no self-perception of tooth wear (957, 64.84%); jaw fatigue when chewing (1054, 64.84%); or locked jaw in the morning or during sleep (1265, 85.70%).
Most respondents in the study sample (1128, 76.42%) reported a negative perception of oral symptoms on the last month and they all (1476, 100.00%) were feeling nervous or ‘stressed’, i.e., during the period of social withdrawal induced by the COVID-19 pandemic. In addition, 869 (58.88%) reported a worsening in symptoms during the current period of social isolation due to the COVID-19 pandemic; 289 (19.58%) started having symptoms of fatigue or pain in the muscles of the face upon awakening and 318 (21.54%) started having muscle fatigue and discomfort in teeth upon awakening. Almost all respondents (1132, 76.69%) reported that symptoms as muscle fatigue and muscle pain, headache, neck, shoulder, and facial pain got worse during the COVID-19 pandemic. Table 2 shows the frequency of deleterious oral habits and the impact of the COVID-19 pandemic. For WHOQOL-bref, the group of respondents had the following scores in the physical (11.97 ±1.47, for mean±SD); psychological (9.87±2.50); social (11.70±4.74); and environmental (14.73 ±3.92) domains. Tey also presented an overall score of 13.79±3.72 (Table 3).
Present deleterious oral habits and COVID-19 pandemic
Scores of WHOQOL-BREF domains and the overall score
The respondents presented the overall self-compassion of 14,71±1,91 (mean±SD); self-kindness of 2,53±1,32; self-judgment of 3,61±1,31; common humanity of 2,82±1,30; isolation of 3,81±1,32; mindfulness of 2,79±1,25; and over-identification of 4,00±1,19 (Table 4).
Overall Self-Compassion Scale (out of 30 points) and six subscales (out of 5 points).
The current study findings suggest that participants have several bruxism symptoms in a high frequency during the pandemic era, such as clenching and grinding of teeth, as well as affecting symptoms, such as muscle fatigue and muscle pain, headache, neck, shoulder, and facial pain. Moreover, the social withdrawal induced by the COVID-19 pandemic may have caused worse well-being of individuals and lower self-compassion.
This work was supported by the Federal University of Alfenas – UNIFAL-MG (Extension Program EDUCADOR Fellowship, Laura Pereira Generoso). This study was funded in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – Brazil (CAPES Fellowship, Lais Leite Ferreira) – Finance Code 001. The authors would like to thank all participants for their time and their willingness to share their experiences, and to the staff that shared the survey via social media and email for helping to facilitate this study.
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04 Mar 2022
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30 Apr 2021
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