Investigation of Sleep and Awake Bruxism Habit Experienced by People Who Quarantined Different Places During the COVID-19 Pandemic Running title: Investigation of Sleep and Awake Bruxism During the COVID-19 Pandemic

Abstract

Introduction:

This study aimed to investigate sleep and awake bruxism habit experienced by people who quarantined different places during the COVID-19 pandemic in the TRNC.

Material and Methods

A 25-question self-reported questionnaire was sent to the patients' mobile phones to measure their demographic information, the level of bruxism habits which they experienced before and during their quarantine period while sleeping and awake, and asked to answer. The answers were evaluated statistically by percentage and chi-square test.

Results

241 people participated in our research. During the quarantine period, there was an increase in awake bruxism and a slight decrease in sleep bruxism. While the feelings worried, scared, panic and hopelessness felt by the participants in the first days of the quarantine decreased in the last days of the quarantine but calm was increased regardless of the place and length of stay in the quarantine. Teeth clenching, teeth grinding and earache were mostly seen in those who stayed in dormitory quarantine.

Conclusion

People's anxiety is increasing in the COVID-19 pandemic and there is a positive correlation between anxiety and both sleep and awake bruxism. Dentists should pay more attention to the signs of bruxism during the examination, especially from people who say that they are in quarantine during the anamnesis. Although the reason for the patient's visit to the doctor may seem like just a simple toothache, the underlying factors such as clenching should not be forgotten with a holistic approach and awareness should be created for the patient.

Introduction

Coronavirus is a disease that causes the severe acute respiratory syndrome. It started in Wuhan in 2019 and a few months later the World Health Organization (WHO) labeled the virus spread across the globe as a pandemic. The risk assessment according to the WHO for COVID-19 is very high, with a global impact. As of April 12, 2020, there were 1,696,588 confirmed cases of COVID-19, including 105,952 deaths, reported by the WHO (1).

To date, all countries which have suffered from the COVID-19, have taken measures, as stated by health authorities, to prevent further spread of the virus and to ensure infection control. Some of these strategies are including the provision of virus tests, extreme social isolation, localized quarantines, and the monitoring of the most vulnerable populations; the measures taken are largely guided by the official WHO website based on the number of cases in each country (2).

With the first Coronavirus case in North Cyprus, the Turkish Republic of Northern Cyprus (TRNC) government took more strict measures than other countries because Cyprus is an island. Because of uncertainty about the ways of virus spread, the appropriate modes of treatment, insufficient availability of health services, and no existing vaccine or efficient drug for treatment all entrances and exits to the island by sea, air, and land were closed and the country is lockdown (3).

A filiation team was formed in TRNC to prevent the spread of the disease. The filiation team uses the contact tracking algorithm published by the Republic of Turkey (TR) and TRNC health ministries. They identify people at high and low COVID-19 risk below the criteria:

With a COVID-19 patient without taking protective measures (without mask or wearing a mask inappropriate use) persons are at high risk in the following situations:

» People who face and talk to a COVID-19 patient at a distance of less than 1 meter for 15 minutes at a time

» Persons providing direct care to a COVID-19 patient,

» Students sharing a classroom with a student/teacher with COVID-19 and teachers,

» People who come into physical contact with a COVID-19 patient (kissing, hugs, etc.)

» People who unprotected contact with secretions (saliva, sputum, etc.) of a COVID-19 patient such as sneezing-coughing

» People who in the same closed environment with a COVID-19 patient (hospital or bank standby halls, title deed, tax office, those waiting in official institutions such as municipality, bus, shuttle, etc. persons with means of transport),

» Passengers who are traveling on the same plane with a COVID-19 patient (sitting two fronts, two back, and two side seats)

» People living in the same house with a COVID-19 patient,

» People who work in the same office with a COVID-19 patient,

» Persons sharing the same room with a COVID-19 patient in a dormitory or hotel,

» People traveling on the same bus with a COVID-19 patient

The main duty of the filiation team is to call the covid positive person and/or their close contacts. Close contact, in this case, would mean anybody, who had been in contact with the positive person within the last 48 hours from being tested positive (4).

The filiation team called the people they considered close contacts by phone and placed them in dorms, hotels, or leave them home. To be able to stay in home quarantine, people had to either live alone at home or have rooms for themselves at home, and they had to have bathrooms and toilets in the room. Otherwise, people were randomly placed in dorms and hotels. In these centers, patients were kept isolated until two negative PCR results were obtained. This period lasted an average of 7 to 21 days.

Bruxism is characterized by clenching and/or grinding of teeth and /or by bracing or thrusting of the jaw muscles. There are 2 different types of bruxism; sleep and awake. Awake bruxism is the form that is seen during the waking period and is usually conscious of the person. Sleep bruxism occurs while the person is sleeping. In sleep bruxism, patients either complain of pain in their jaw when they wake up in the morning or are observed by a relative to clench their teeth during the night. While the diagnosis of bruxism obtained by asking questions to the person gives us the possible diagnosis, a dentist's examination is essential for a definitive diagnosis (5–8).

Many studies have shown that one of the most important reasons for bruxism is psychosocial stress. The quarantine process has caused many changes in people's social lives, which has affected the habit of bruxism (3, 5, 6, 9–12). During the quarantine period, people have different problems such as; losing their job, decreased income level, starting to have marital problems, being away from their children, thinking that their health will the study aimed to deteriorate, getting bad news from social media, immobility, deterioration of their appearance (weight gain, hair growth, hair dye coming in, etc.), being dissatisfied with their stay, not being social, learning that they have lost their relative or been hospitalized during their stay in. They experienced varied emotional states like worried, scared, in a panic, hopeless and calm in their life (2, 9, 13).

With this research, which is conducted for the first time in TRNC, we aim to evaluate the bruxism habits of people who were in contact due to the COVID-19 pandemic and remain in quarantine while they are asleep and awake, and the effect of the difference in the quarantine environment on bruxism.

Material And Methods

This study is a retrospective descriptive study. The sample of the study consists of people who were accepted as close contacts between 1–31 July 2021 and remained in quarantine. The information of the patients was obtained from the sources of the filiation team.

Messages were sent to 2528 participants. The message could not be delivered to 160 of them because their phones were switched off or could not be reached. To get information from the people, a questionnaire consisting of 25 questions prepared by the researcher in the light of the literature was used. The questionnaire was created to determine 6 questions to obtain demographic information and then 19 questions to measure bruxism habits before and during the quarantine period.

Our inclusion criteria were determined as staying in quarantine between 1–31 July 2021, being in close contact with a person infected with corona, being 18 years old and over, speaking Turkish people, using a mobile phone. Since the study was based on volunteerism, the message was sent to the individuals, and those who responded within a week were included in the study. The questionnaire was sent to a total of 2368 people and 241 people among them responded.

As the criteria for exclusion from the study, those whose PCR results were positive during the quarantine process were determined as foreign nationals and people under the age of 18 who remained in quarantine. Moreover, if the phone numbers were the same for a family, only one person participated in the study.

The study protocol was approved by Dr. Burhan Nalbantoglu state hospital (date:12.07.21 and reference code number:38/21) ethics committee. All procedures performed in studies involving human participants were following the ethical standards of the hospital and/or hospital research committee and with the 1964 Helsinki declaration.

The answers were analyzed by percentage and chi-square analysis.

Results

Participants were 152 females (63.1%) and 89 males (36.9%) in our study with a sample size of 241. 32.8% were between the ages of 30–39, 17.8% were between the ages of 40–49 and 5% were between the ages of 50–59. 32.8% were between the ages of 30–39, 17.8% were between the ages of 40–49 and 5% were between the ages of 50–59. They were 151 (62.7%) university, 45 (18.7%) high school, 12 (5%) master and 10 (4.1%) doctoral level.

The answer to the question of relationship status was 51% married. 25.7% single, 11.6% I have a relationship, and 6% engaged. 121(50.2%) of the study participants had children and 97 of them were younger than 18 years old.

When asked to the participants "Have you ever been to a dental checkup?" 215(89.2%) of them answered “Yes” to the question and 75(31.1%) of them told their dentist that they clenched or grinded their teeth. After the quarantine period, 85 (35.3%) of the participants went to the dentist control and 26 (10.8%) of them said that the dentist clenched or grinded their teeth.

Before the quarantine period, 67(27.8%) of the participants said "Yes" to the question "Did you notice that you were clenching your teeth while awake or did someone tell you", this rate increased to 68(28.8%) during the quarantine period. Before the quarantine period, 69(28.6%) of the participants said "Yes" to the question "Did you notice that you were clenching your teeth in sleep or did someone tell you", this rate decreased to 67(27.8%) during the quarantine period (Table 1).

When you wake up in the morning before the quarantine period, 70 (29%) of the participants answered yes to the question of whether you had fatigue, tension, and pain in your jaw, while this rate increased to 72 (29.8%) people during the quarantine period.

51.9% of the participants in the research stated that they stayed in the home quarantine, 37.8% in the hotel quarantine, and 10.4% in the dorm quarantine. It was found that 78.8% of the participants answered once, 16.2% two times, 3% three times, and 2% four or more times to the question of how many times you stayed in quarantine. To the question of “How many days you stayed in quarantine”, 61.4% of the participants answered 8–14 days, 20.7% 1–7 days, 12% 15–21 days, and 5.8% 22 days and above.

In the first days of the quarantine, it was seen that 28% of those staying at the dorm quarantine, 31.9% of those staying at the hotel quarantine, and 33.6% of those staying at home quarantine felt much or too much worried. 24% of those staying at the dorm quarantine, 18.7% of those staying at the hotel quarantine, and 21.6% of those staying at home quarantine felt much or too much scared. 24% of those staying at the dorm quarantine, 17.6% of those staying at the hotel quarantine, and 19.2% of those staying at home quarantine felt much or too much hopelessness. 28% of those staying at the dorm quarantine, 34.1% of those staying at the hotel quarantine, and 25.6% of those staying at home quarantine felt much or too much calm (Table 2).

In the last days of the quarantine, it was seen that 12% of those staying at the dorm quarantine, 14.3% of those staying at the hotel quarantine, and 12.8% of those staying at home quarantine felt much or too much worried. 16% of those staying at the dorm quarantine, 8.8% of those staying at the hotel quarantine, and 11.2% of those staying at home quarantine felt much or too much scared. 12% of those staying at the dorm quarantine, 7.7% of those staying at the hotel quarantine, and 8.8% of those staying at home quarantine felt much or too much in a panic. 20% of those staying at the dorm quarantine, 5.5% of those staying at the hotel quarantine, and 12.8% of those staying at home quarantine felt much or too much hopelessness. 32% of those staying at the dorm quarantine, 40.7% of those staying at the hotel quarantine, and 38.4% of those staying at home quarantine felt much or too much calm (Table 3).

The factors which affected you during your quarantine were asked. 8% of those staying at the dorm quarantine, 3.3% of those staying at the hotel quarantine, and 5.6% of those staying at home quarantine chose the option to lose their job. 36% of those staying at the dorm quarantine, 23.1% of those staying at the hotel quarantine, and 19.2% of those staying at home quarantine chose the option to decrease income level. 8% of those staying at the dorm quarantine, 7.7% of those staying at the hotel quarantine, and 0.8% of those staying at home quarantine chose the option to start to have marital problems. 28% of those staying at the dorm quarantine, 17.6% of those staying at the hotel quarantine, and 15.2% of those staying at home quarantine chose the option of being away from my children. 32% of those staying at the dorm quarantine, 23.1% of those staying at the hotel quarantine, and 22.4% of those staying at home quarantine chose the option thinking that their health will deteriorate. 12% of those staying at the dorm quarantine, 13.2% of those staying at the hotel quarantine, and 15.2% of those staying at home quarantine chose the option of getting bad news from social media. 44% of those staying at the dorm quarantine, 41,8% of those staying at the hotel quarantine, and 33.6% of those staying at home quarantine chose the option immobility. 16% of those staying at the dorm quarantine, 6.6% of those staying at the hotel quarantine, and 3.2% of those staying at home quarantine chose the option deterioration of my appearance. 24% of those staying at the dorm quarantine, 20.9% of those staying at the hotel quarantine, and 3.2% of those staying at home quarantine chose the option of being dissatisfied with my stay. 36% of those staying at the dorm quarantine, 24.2% of those staying at the hotel quarantine, and 35.2% of those staying at home quarantine chose the option of not being social. 4% of those staying at the dorm quarantine, 4.4% of those staying at the hotel quarantine, and 10.4% of those staying at home quarantine chose the option of learning that I have lost a relative or being hospitalized during my stay (Table 4).

During your stay in quarantine, the question was asked which of the following(s) you experienced. 16% of those staying at the dorm quarantine, 7.7% of those staying at the hotel quarantine, and 4% of those staying at home quarantine chose the option pain in my jaw as much or too much. 8% of those staying at the dorm quarantine, 2.2% of those staying at the hotel quarantine, and 1.6% of those staying at home quarantine chose the option earache as much or too much. 32% of those staying at the dorm quarantine, 12.1% of those staying at the hotel quarantine, and 4.1% of those staying at home quarantine chose the option of clenching teeth as much or too much. 28% of those staying at the dorm quarantine, 3.3% of those staying at the hotel quarantine, and 1.6% of those staying at home quarantine chose the option of grinding teeth as much or too much. 16% of those staying at the dorm quarantine,17.6% of those staying at the hotel quarantine, and 19.2% of those staying at home quarantine chose the option headache as much or too much. 4% of those staying at the dorm quarantine, 7.7% of those staying at the hotel quarantine, and 5.6% of those staying at home quarantine chose the option noise from the jaw when opening and closing the mouth as much or too much. 8% of those staying at the dorm quarantine, 4.4% of those staying at the hotel quarantine, and 0.8% of those staying at home quarantine chose the option difficulty in mouth opening as much or too much. 4% of those staying at the dorm quarantine, 1.1% of those staying at the hotel quarantine, and 0.8% of those staying at home quarantine chose the option of locking their jaw as much or too much. 4% of those staying at the dorm quarantine, 3.3% of those staying at the hotel quarantine, and 1.6% of those staying at home quarantine chose the option of facial swelling as much or too much. 8% of those staying at the dorm quarantine, 3.3% of those staying at the hotel quarantine, and 4% of those staying at home quarantine chose the option of eating difficulty as much or too much (Table 5).

Discussion

COVID-19 has interfered with global and social-economic such as travel plans, work, and normal life activities, causing unexpected deaths and illnesses. Studies have already been reported that moderate and severe anxiety occurs in a high percentage of the population with COVID-19. Suspicious and even inaccurate information about the disease, the lack of information on the affected areas, the number of infected people, and the actual death rate have led to fear and distrust among the public. People and states preferred social isolation, which is the safest method of protection, to fully understand what the existing disease is and to prevent its spread. Social isolation is associated with both physical and mental health. Many different factors such as, were dismissed, decreased income level, marital problems, staying away from children, thinking that their health would deteriorate, getting bad news from social media, immobilization, deterioration of appearance, being dissatisfied with the living environment, not being able to socialize, hospitalization or death of a relative caused increased stress level in people who were in quarantine (11, 13, 14). In our study, we asked these questions to the participants. Receiving bad news from social media and learning that a relative's condition deteriorated and was hospitalized or died was higher among those who remained in-home quarantine. In all other questions, it was observed that those who remained in dorm quarantine were affected at a higher rate.

There is a positive correlation between bruxism and stress. It has been observed that the habit of bruxism increases in the population with high-stress levels (7–9, 11, 12). Bruxism while sleep and awake are recognized as different entities with different etiologies. Awake bruxism has been associated with psychological factors such as anxiety, stress, and negative emotions. It has been reported that the frequency of awake bruxism is 5–6 times higher than normal in individuals under high stress but the role of psychology in sleep bruxism is still controversial (2, 9). According to a researcher, it is thought that stress impairs sleep quality and increases the transition between REM and non-REM sleep periods, thus increasing micro-stimulation in the jaw muscles (7). In our study, it was observed that the frequency of those who said that they had a higher level of teeth grinding problem while awake, increased during the quarantine period compared to before. An increase was also reported during the quarantine for those who responded too much to the clenching problem while sleeping before the quarantine period.

In awake bruxism, possible bruxism can be identified with self-report questionnaires. However, it is difficult to diagnose bruxism while sleeping in people who live alone and when no measurement (polysomnographic measurement) is made. To give a definitive diagnosis in both types of bruxism, the person should be examined and diagnosed by a dentist (5, 7). In our study, most of the participants give importance to oral and dental health and go to the dentist. It was observed that of those participating in the study one-third of them had a habit of clenching, which the dentist detected and told the patient before the quarantine. It was found that one-third of those who went to the dentist before the quarantine period went to the dentist again after the quarantine period due to dental problems.

It has been observed that there was a slight increase in the quarantine period in people who noticed that they were clenching their teeth while awake or someone told them before the quarantine period. On the other hand, there has been a decrease in the proportion of people who noticed that they were grinding their teeth while sleeping or someone told them before the quarantine period. In the self-reported questionnaires in which the clenching of the teeth while sleeping and awake is investigated, false-positive answers can be obtained, especially in the clenching of the teeth while sleeping (8). The reason for this may be that the participants are alone in quarantine and cannot realize this situation on their own or participants perceive them a single answer that does not provide proper diagnosis through self-reported questionnaires.

In self-reported approaches, pain or fatigue in the masticatory muscles of the patients can be considered as bruxism. However, in clinical evaluation, pain in the masticatory muscles is used to diagnose both TMD and bruxism (8). In our study, when the participants were asked about the fatigue, tension, and pain in the jaw when they woke up in the morning, there was no significant difference between what they felt before and during the quarantine period.

In the study of Cotrin et al., participants in the study were aware of the seriousness of the coronavirus and high anxiety levels were observed in those who remained in quarantine. In studies, it has been observed that home quarantine is usually applied to people during the pandemic. Unlike other studies, our study consisted of people who were considered as contacts who stayed in hotel quarantine and dorm quarantine apart from home quarantine. Participants in our study were asked in which emotional states (worried, scared, in a panic, hopeless and calm) they felt in the first and last days of quarantine, how many times, and how long have been in quarantine. The length and frequency of the quarantine period did not affect the mood of the groups. Those who stayed at home in the first days of the quarantine showed more worried than those who stayed in dorms and hotels. It can be thought that the reason for this is the possibility of infection the disease to other people in the home. On the other hand, the feelings of being scared, in a panic, and hopeless were most common among those staying in the dorm quarantine. The reason for this may be that they are far from their relatives and they are in the dormitory environment. Hotel stayers were found to be the calmest during the first days of quarantine. The reason for this may be that they feel like they are in a holiday environment. In the last days of the quarantine, regardless of the place, length, and frequency of stay, worried, scared, in a panic, and hopelessness decreased, and calm increased in all groups. Psychological and somatic reactions experienced by people may be relieved within hours. For this reason, time is spent in the same place the person adapts to the situation (2, 3, 6, 9, 11, 14–16).

One of the common causes of ear pain felt in the temporomandibular region is bruxism, which is often accompanied by stress and anxiety (17). Those who stayed in the dorm quarantined experienced statistically significant complaints of earache, clenching, and grinding teeth compared to other hotel and home quarantined groups.

Relationship status can also affect stress, anxiety, and depression. Married people have more anxiety during quarantine (18). In our study more than half of the participants are married however, it was observed that those who stayed at the dorm quarantine and the hotel quarantine started to experience marital problems in a statistically significant way compared to those who stayed at home quarantine.

In our study, most of those who were married had children under the age of 18, which means they need parental care and family support. Being away from their homes and children due to quarantine causes more stress for parents and maybe they do not receive sufficient support from the people with whom they are together.

Self-reported questionnaires are a reliable parameter for measuring possible bruxism habits (5, 8). It provides an advantage in terms of seeing the problem quickly, but it is difficult to get people to answer the questionnaire because it is voluntary (14). Because of that, this research does not include the whole country, but only people who remain in contact in quarantine within 1 month.

Conclusion

Regardless of the source, there is a seriously positive relationship between anxiety and dental health. For this reason, especially in a high-stress situation like a pandemic; dentists should take detailed anamnesis to evaluate the patient's situation well and make a diagnosis and treatment accordingly.

Although the reason for the patient's visit to the doctor may seem like just a simple toothache, the underlying factors such as clenching should not be forgotten and investigating the possible aetiologies of the patient with a holistic approach. It is possible to prevent bruxism habits by increasing the awareness of people. Tooth erosion, jaw pain, and locking can be reduced in the following years of these people.

In our research group, it was determined that the awareness of clenching was low. Considering the temporomandibular joint problems and muscle spasms that clenching may cause in the future, it is understood once again how important it is to increase this awareness.

Declarations

Funding: This research received no external funding.

Ethical Review Board Statement: The study was conducted according to the guidelines of the Declaration of Helsinki and approved by the Ethics Committee of Dr. Burhan Nalbantoglu's government hospital. (Protocol code:38/21 and 12.07.2021).

Informed Consent Statement: Written informed consent has been obtained from the patients to publish this paper.

Data Availability Statement: The datasets used and/or analysed during the current study available from the corresponding author on reasonable request.

Conflicts of Interest: The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.

Authors’ contributions: Bedriye Gizem Çelebioğlu Genç  was a principal investigator and a major contributor in data collection, data entry, manuscript writing, and literature search.  Kaan Orhan was  co-investigator and supervisor in the study.  All authors have read and approved the manuscript.

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