- Journal List
- Springer Nature - PMC COVID-19 Collection
- PMC8239479
As a library, NLM provides access to scientific literature. Inclusion in an NLM database does not imply endorsem*nt of, or agreement with, the contents by NLM or the National Institutes of Health.
Learn more: PMC Disclaimer | PMC Copyright Notice
J Orofac Orthop. 2022; 83(6): 1–6.
Published online 2021 Jun 29. doi:10.1007/s00056-021-00315-0
PMCID: PMC8239479
PMID: 34185102
Language: English | German
Elif Kardeş
1 and Sinan Kardeş2
Author information Article notes Copyright and License information PMC Disclaimer
Abstract
Purpose
Whether coronavirus disease 2019 (COVID-19) pandemic has an impact on bruxism represents an important gap of knowledge. This study evaluated the trends in Google searches, as an indication of public interest and demand, for bruxism and its symptoms during the COVID-19 pandemic.
Methods
Google Trends was queried for bruxism, teeth grinding, and teeth clenching both worldwide and in the United States. Two periods in 2020 (March15–May9 and May10–October17) were compared to similar periods of 2016–2019 to investigate both initial and short-term interest.
Results
The relative search volume of bruxism, teeth grinding, and teeth clenching was not significantly different between 2020 and 2016–2019 worldwide or in the United States in the March 15–May9 period. Only the search for teeth grinding showed an increase worldwide. In the May10–October17 period, the relative search volume of bruxism, teeth grinding, and teeth clenching all was significantly higher in 2020 compared to 2016–2019 both worldwide and in the United States.
Conclusion
The study showed that the relative search volume for bruxism, teeth grinding, and teeth clenching, as an indication of public interest and demand, was increased both worldwide and in the United States during the May–October 2020 period compared to similar periods of the previous 4years. Dentists should address this increased public interest and demand for information seeking for bruxism. Follow-up studies monitoring long-term interest as areal-time surveillance and evaluating whether increased internet searches are linked to an actual increase or worsening of bruxism and its symptoms in the clinic are required.
Keywords: Google Trends, Internet search engines, Psychological distress, Dentistry, Dentists
Abstract
Ziel
Ob die COVID(„coronavirus disease 2019“)-Pandemie einen Einfluss auf Bruxismus hat, stellt eine wesentliche Forschungslücke dar. In dieser Studie wurden die Trends in den Google-Suchanfragen, als Anhaltspunkt für öffentliches Interesse und die entsprechende Nachfrage, für Bruxismus und seine Symptome während der COVID-19-Pandemie ausgewertet.
Methoden
Google Trends wurde für Bruxismus, Zähneknirschen und Zähnepressen sowohl weltweit als auch in den USA abgefragt. Zwei Zeiträume im Jahr 2020 (15.03.–09.05. und 10.05.–17.10.) wurden mit ähnlichen Zeiträumen der Jahre 2016–2019 verglichen, um sowohl das initiale als auch das kurzfristige Interesse zu untersuchen.
Ergebnisse
Das relative Aufkommen der Suchanfragen zu Bruxismus, Zähneknirschen und Zähnepressen unterschied sich im Zeitraum vom 15.03.–09.05. weder weltweit noch in den USA statistisch signifikant zwischen 2020 und 2016-2019. Nur die Suche nach Zähneknirschen zeigte weltweit einen Anstieg. Im Untersuchungszeitraum 10.05.–17.10. war das relative Suchvolumen bezüglich Bruxismus, Zähneknirschen und Zähnepressen im Jahr 2020 im Vergleich zu 2016–2019 sowohl weltweit als auch in den USA signifikant höher.
Schlussfolgerung
Die Studie zeigte, dass das relative Suchvolumen für Bruxismus, Zähneknirschen und Zähnepressen als Hinweis auf öffentliches Interesse und Nachfrage sowohl weltweit als auch in den Vereinigten Staaten während des Zeitraums von Mai bis Oktober 2020 im Vergleich zu ähnlichen Zeiträumen der vorangegangenen 4 Jahre erhöht war. Zahnärzte sollten dieses erhöhte öffentliche Interesse und die Nachfrage nach Informationen über Bruxismus ansprechen. Folgestudien, die das langfristige Interesse im Sinne einer Echtzeitüberwachung beobachten und auswerten, ob die erhöhte Internetsuche mit einer tatsächlichen Zunahme oder einer Verstärkung von Bruxismus und seinen Symptomen in der Klinik verbunden ist, sind erforderlich.
Schlüsselwörter: Google Trends, Internetsuchmaschinen, Psychische Belastungen, Zahnmedizin, Zahnärzte
Introduction
The rapid spread of the coronavirus disease 2019 (COVID-19) pandemic resulted in 38,202,956 confirmed cases and 1,087,069 deaths worldwide, as of October15, 2020 [1]. To control its widespread transmission, containment measures were implemented including strict quarantine and lockdown. These measures triggered an economic recession and financial crisis with an unprecedented rise in unemployment [2, 3]. The health crisis coupled with its negative social and economic consequences have led to aconsiderable increase in levels of psychological distress and sleep disorders as well as in alcohol consumption among the general population [4–8].
Google (Google LLC, Mountain View, CA, USA) searches data have been used to track public interest in abroad range of dental topics such as dental carries, molar incisor hypomineralization, and amber necklace [9–11]. Furthermore, in arecent infodemiological study the seasonality of Google searches of bruxism and its symptoms was evaluated [12]. In the context of the COVID-19 pandemic, Google searches data have been leveraged to evaluate public interest in COVID-19 terms [13, 14], mental health issues [15, 16], and insomnia [17]. All these studies demonstrate Google searches as being apowerful tool in monitoring public interest.
Although psychological distress, sleep disorders as well as high alcohol consumption are well-documented risk factors for bruxism [18–22], whether COVID-19 pandemic has an impact on bruxism represents an important gap of knowledge. To address this major gap, the present study evaluated the trends in Google searches, as an indication of public interest and demand, for bruxism and its symptoms during the COVID-19 pandemic.
Materials and methods
The present study followed the recommendations of the recent article by Mavragani etal. addressing the methodological framework in using Google Trends in health research [23]. The Google Trends tool and data are explained in detail elsewhere [24, 25]. In brief, Google Trends, afreely accessible tool, provides information on trends of keywords that people search for on Google. It allows exploring variations both in individual countries and worldwide. Google Trends normalizes search data to the time period and region selected, and then transforms it to a0–100 scale for making comparisons easier. Greater values indicate greater relative search volume (RSV).
The Google Trends was queried for the three keywords: (1)bruxism, (2)teeth grinding, and (3)teeth clenching. Time period of search was set to January01, 2016, to October20, 2020, with aselection of all categories. This search strategy was performed worldwide and in the United States, the most affected country in terms of COVID-19cases and deaths. All RSV data were downloaded for exploring the trends.
Two periods in 2020 (March15–May9 and May10–October17) were compared to similar periods of the previous 4years (2016–2019) to investigate both initial and short-term interest. In addition, atime series chart was generated to visualize the trends for bruxism, teeth grinding, and teeth clenching in 2016–2019 and 2020. Weekly data were transformed to monthly data for the time series chart. The World Health Organization (WHO) declared apandemic just before mid-March; therefore, dates after March15, 2020 were chosen in comparisons. The first period (March15–May9) coincides with implemented quarantine measures just after the WHO declaration of apandemic; therefore, it provides the interest during the initial phase of the pandemic. The second period provides the interest during the pandemic period, which coincides with lightening/lifting the imposed quarantine measures. Ageneralized estimating equation with agamma distribution was utilized in the comparisons. Statistical analysis was performed in SPSS® v.21.0 (IBM, Armonk, NY, USA) and the time series chart was generated on Excel v.14.3.7 (Microsoft, Redmond, WA, USA) and data were presented as per standard recommendations [26].
Results
In the initial period, March15–May9, the relative search volume of bruxism and teeth clenching was not significantly different between 2020 and 2016–2019 worldwide or in the United States. In this period, the worldwide relative search volume of teeth grinding (change: 11.5%, p = 0.017) was significantly higher in 2020 than in 2016–2019; however, it was not significantly different in the United States (change: 5.2%, p = 0.304) (Table1).
Table 1
Relative search volume of bruxism, teeth grinding, and teeth clenching worldwide and in the United States
Relatives Aufkommen von Anfragen zu Bruxismus, Zähneknirschen und Zähnepressen weltweit und in den USA
| March15–May9 | May10–October17 | |||||||
|---|---|---|---|---|---|---|---|---|
| 2020 | 2016–2019 | % Change | Pvalue | 2020 | 2016–2019 | % Change | Pvalue | |
| Bruxism | ||||||||
| Worldwide | 47.6 (44.4–51.1) | 45.0 (42.3–47.1) | 6.8 (−2.7–16.3) | 0.152 | 52.2 (50.6–53.8) | 42.2 (40.9–43.6) | 23.6 (18.2–29.0) | < 0.001 |
| United States | 61.3 (57.1–65.8) | 63.2 (58.2–68.6) | −3.0 (−13.5–7.5) | 0.581 | 67.7 (64.5–71.0) | 61.6 (59.0–64.4) | 9.8 (2.7–17.0) | 0.005 |
| Teeth grinding | ||||||||
| Worldwide | 83.0 (76.7–89.8) | 74.4 (71.7–77.2) | 11.5 (1.9–21.2) | 0.017 | 89.5 (86.9–92.2) | 71.7 (70.1–73.4) | 24.9 (20.2–29.5) | < 0.001 |
| United States | 68.9 (63.3–75.0) | 65.5 (62.7–68.3) | 5.2 (−4.8–15.2) | 0.304 | 73.7 (71.4–76.1) | 63.0 (61.4–64.5) | 17.2 (12.4–21.9) | < 0.001 |
| Teeth clenching | ||||||||
| Worldwide | 64.6 (58.3–71.7) | 61.0 (56.6–65.7) | 6.0 (−7.5–19.5) | 0.376 | 71.2 (65.5–77.4) | 58.1 (55.3–61.1) | 22.5 (10.7–34.4) | < 0.001 |
| United States | 62.9 (58.6–67.5) | 61.9 (57.9–66.2) | 1.6 (−8.3–11.5) | 0.748 | 70.7 (66.0–75.6) | 62.2 (59.9–64.5) | 13.6 (4.9–22.4) | 0.002 |
Open in a separate window
Relative search volume values are presented as amean (95% confidence interval) (generalized estimating equations)
In the May10–October17 period, the relative search volume of bruxism (worldwide, change: 23.6%, p < 0.001; United States, change: 9.8%, p = 0.005), teeth grinding (worldwide, change: 24.9%, p < 0.001; United States, change: 17.2%, p < 0.001), and teeth clenching (worldwide, change: 22.5%, p < 0.001; United States, change: 13.6%, p = 0.002) was significantly higher in 2020 than in 2016–2019 (Table1).
Fig.1 shows that the relative search volume of bruxism, teeth grinding, and teeth clenching was numerically similar in 2020 and in 2016–2019 in March; then it was numerically higher in all the other months (April through October) in 2020 compared to the mean of 2016–2019 both worldwide and in the United States.
Fig. 1
Relative search volume of (a)bruxism worldwide, (b)bruxism in the United States, (c)teeth grinding worldwide, (d)teeth grinding in the United States, (e)teeth clenching worldwide, (f)teeth clenching in the United States. The data of October was based on partial data of October
Relatives Volumen von Suchanfragen für (a)Bruxismus weltweit, (b)Bruxismus in den USA, (c)Zähneknirschen weltweit, (d)Zähneknirschen in den USA, (e)Zähneknirschen weltweit, (f)Zähneknirschen in den USA. Die Daten vom Oktober basierten auf Teildaten vom Oktober
Discussion
The study found that the relative search volume of bruxism, teeth grinding, and teeth clenching was not significantly different between 2020 and 2016–2019 worldwide or in the United States in the initial period, March15–May9. Only the search for teeth grinding showed an increase worldwide. However, after the initial period, the relative search volume of bruxism, teeth grinding, and teeth clenching increased and was significantly higher in 2020 compared to 2016–2019 both worldwide and in the United States.
In the initial period, relative search volume of bruxism and teeth clenching was not different between 2020 and 2016–2019 worldwide. In addition, the relative search volume of bruxism, teeth grinding and teeth clenching was not different between 2020 and 2016–2019 in the United States. Previous studies using Google Trends showed that in this initial period the relative search volume of COVID-19 terms (e.g., coronavirus), COVID-19 symptoms (e.g., cough, diarrhea, and loss of smell) and some mental health issues (e.g., anxiety) increased but the relative search volume of general health issues (e.g., dermatologic conditions and rheumatic diseases) decreased [13–16, 27–34]. We believe that our finding (no difference) in the initial period is important considering the previous studies’ results that showed asignificant decrease in general health issues reflecting ashift of public interest from general health issues to COVID-19 [32–34]. Therefore, our finding indicates that the public remarkably searched for bruxism and its symptoms in the initial pandemic period. After the initial period, relative search volume of bruxism, teeth grinding and teeth clenching all were significantly increased compared to similar periods of the previous 4years. This finding may indicate that the COVID-19 pandemic had anegative impact on bruxism and its symptoms. Several factors might have contributed to this observed increase. COVID-19-related deaths, strict quarantine/lockdown measures, and economic recession/financial crisis/rise in unemployment have led to considerable increases in the levels of psychological distress in the general public [4, 6]. Furthermore, alcohol consumption has increased during the pandemic [8]. Since psychological distress as well as high alcohol consumption are well-documented risk factors for bruxism [18–22], the increase in intensity of these risk factors might have led to or worsen existing bruxism. Although the present findings require verification with clinical studies, healthcare providers should address the increased public interest and demand for information regarding bruxism.
Previous studies evaluated the trends in Google searches for mental health issues and insomnia [15–17]. ho*rger etal. compared mental health-related Google searches in the United States during the initial pandemic period (first 40days following March11,2020) with the prepandemic period [15]. They found significant increases in searches related to worry, panic, and anxiety; however, no significant changes were detected in searches related to depression, loneliness, or suicide in the initial pandemic period compared with the prepandemic period [15]. They suggested continued surveillance of Google searches for these terms because changes in these terms may occur later [15]. Ayers etal. evaluated the search terms for anxiety or panic in combination with attack in the United States. They found that acute anxiety searches were higher than expected for the initial pandemic period (first 58days following March13, 2020) [16]. In astudy examining Google searches for insomnia worldwide and in the United States, Zitting etal. showed adecrease in searches for insomnia in March and then alarge increase in April and May 2020 [17]. The present study provides insights into the potential impact of the COVID-19 pandemic on bruxism and its symptoms.
Two previous cross-sectional studies using online surveys to investigate the population’s self-reported bruxism symptoms and their worsening during the COVID-19 pandemic are available in the literature [35, 36]. In the study by Emodi-Perlman etal., atotal of 700participants from Israel and 1092participants from Poland fully completed the survey [35]. They found that 40 and 32% of Israeli and 68 and 50% of Polish participants reported possible/probable awake bruxism and possible/probable sleep bruxism, respectively [35]. They also showed that 16 and 13% of Israeli and 34 and 28% of Polish participants reported awake bruxism aggravation and sleep bruxism aggravation, respectively [35]. In the other cross-sectional study by Javaid etal., 1021participants from around the world completed the survey [36]. They found that 13% of participants reported bruxism symptoms during the pandemic [36]. Furthermore, in an overview article, Hassan and Khier hypothesized that awake bruxism might be triggered/worsened during the pandemic due to increased/accumulated stress [37]. The design of the present study differs from the previously published two survey studies and our results indicate increased internet searches for bruxism and its symptoms during the pandemic.
Limitations
There were limitations with the present study. First, we only analyzed Google engine searches. However, since approximately 90% of all internet searches conducted on it [38], Google searches may be representative for all internet searches. Second, Google Trends does not allow analyzing in various subpopulations (e.g., male/female). Therefore, the results are only applicable for whole population. Third, internet use may be lower in some subpopulations (e.g., illiterate, older adults); hence, these subpopulations might be excluded or underrepresented. Fourth, our search strategy was by no means exhaustive—rather, focused only on internet searches for bruxism and its symptoms (i.e., teeth grinding and teeth clenching). Adding some other keywords such as headache, toothache, neck pain, and jaw pain into our search strategy would have managed to allow abetter interpretation of the study results. Fifth, we have no information on the motivation or intention of internet searches for bruxism, teeth grinding and teeth clenching. It is possible that an increased number of popular scientific health-related publications on bruxism may lead to arise in its internet searches or increased interest in seeking head and neck pain-related information might contribute to searches for bruxism. Considering these possible factors/reasons behind the observed increase in internet searches, it is not possible to attribute all the changes only to the pandemic. Furthermore, the study provided no evidence of whether the COVID-19 pandemic has caused an increasing demand for dental treatment. Sixth, the global results of the study should be interpreted with caution and by bearing in mind the facts that the seasons are reversed between northern and southern hemispheres and previous studies showed seasonality in internet searches of several health topics including bruxism [12]. Seventh, we were able to investigate only initial and short-term interest. Afollow-up study is needed to monitor long-term interest as areal-time surveillance. Lastly, whether the present findings are associated with actual increase or worsening in bruxism and its symptoms deserves future evaluation.
Conclusion
The present study showed that the relative search volume for bruxism, teeth grinding, and teeth clenching, as an indication of public interest and demand, was increased both worldwide and in the United States during the May–October 2020 period compared to similar periods of the previous 4years. Dentists should address this increased public interest and demand for information seeking for bruxism. Follow-up studies monitoring long-term interest as areal-time surveillance and evaluating whether increased internet searches are linked to an actual increase or worsening of bruxism and its symptoms in the clinic are required.
Conflict of interest
E.Kardeş and S.Kardeş declare that they have no competing interests.
Footnotes
Publisher’s Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Contributor Information
Elif Kardeş, Email: moc.liamg@sedrakfile.
Sinan Kardeş, Email: rt.ude.lubnatsi@sedrak.nanis.
References
1. World Health Organization https://covid19.who.int/. Accessed 15 Oct 2020
2. OECD (2020) News release: G20 GDP growth quarterly national accounts. Paris. https://www.oecd.org/sdd/na/g20-gdp-growth-Q2-2020.pdf/ (Created 14 Sept 2020). Accessed 15 Oct 2020
3. OECD (2020) OECD unemployment rates news. Paris. https://www.oecd.org/sdd/labour-stats/unemployment-rates-oecd-09-2020.pdf/ (Created 9 Sept 2020). Accessed 15 Oct 2020
4. Xiong J, Lipsitz O, Nasri F, Lui LMW, Gill H, Phan L, Chen-Li D, Iacobucci M, Ho R, Majeed A, McIntyre RS. Impact of COVID-19 pandemic on mental health in the general population: a systematic review. J Affect Disord. 2020 doi:10.1016/j.jad.2020.08.001. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
5. Marroquín B, Vine V, Morgan R. Mental health during the COVID-19 pandemic: effects of stay-at-home policies, social distancing behavior, and social resources. Psychiatry Res. 2020;293:113419. doi:10.1016/j.psychres.2020.113419. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
6. Singh S, Roy D, Sinha K, Parveen S, Sharma G, Joshi G. Impact of COVID-19 and lockdown on mental health of children and adolescents: a narrative review with recommendations. Psychiatry Res. 2020;293:113429. doi:10.1016/j.psychres.2020.113429. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
7. Holman EA, Thompson RR, Garfin DR, Silver RC. The unfolding COVID-19 pandemic: a probability-based, nationally representative study of mental health in the United States. Sci Adv. 2020;6:eabd5390. doi:10.1126/sciadv.abd5390. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
8. Pollard MS, Tucker JS, Green HD., Jr Changes in adult alcohol use and consequences during the COVID-19 pandemic in the US. JAMA Netw Open. 2020;3:e2022942. doi:10.1001/jamanetworkopen.2020.22942. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
9. Aguirre PE, Coelho M, Oliveira T, Rios D, Cruvinel AF, Cruvinel T. What can Google inform us about people’s interests regarding dental caries in different populations? Caries Res. 2018;52:177–188. doi:10.1159/000485107. [PubMed] [CrossRef] [Google Scholar]
10. Aguirre PEA, Strieder AP, Lotto M, Oliveira TM, Rios D, Cruvinel AFP, Cruvinel T. Are the Internet users concerned about molar incisor hypomineralization? An infoveillance study. Int J Paediatr Dent. 2020;30:27–34. doi:10.1111/ipd.12579. [PubMed] [CrossRef] [Google Scholar]
11. Strieder AP, Aguirre PEA, Lotto M, Cruvinel AFP, Cruvinel T. Digital behavior surveillance for monitoring the interests of Google users in amber necklace in different countries. Int J Paediatr Dent. 2019;29:603–614. doi:10.1111/ipd.12500. [PubMed] [CrossRef] [Google Scholar]
12. Kardeş S, Kardeş E. Seasonality of bruxism: evidence from Google trends. Sleep Breath. 2019;23:695–701. doi:10.1007/s11325-019-01787-6. [PubMed] [CrossRef] [Google Scholar]
13. Husain I, Briggs B, Lefebvre C, Cline DM, Stopyra JP, O’Brien MC, Vaithi R, Gilmore S, Countryman C. Fluctuation of public interest in COVID-19 in the United States: retrospective analysis of Google trends search data. JMIR Public Health Surveill. 2020;6:e19969. doi:10.2196/19969. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
14. Effenberger M, Kronbichler A, Shin JI, Mayer G, Tilg H, Perco P. Association of the COVID-19 pandemic with Internet search volumes: a Google trendsTM analysis. Int J Infect Dis. 2020;95:192–197. doi:10.1016/j.ijid.2020.04.033. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
15. ho*rger M, Alonzi S, Perry LM, Voss HM, Easwar S, Gerhart JI. Impact of the COVID-19 pandemic on mental health: real-time surveillance using Google trends. Psychol Trauma. 2020;12:567–568. doi:10.1037/tra0000872. [PubMed] [CrossRef] [Google Scholar]
16. Ayers JW, Leas EC, Johnson DC, Poliak A, Althouse BM, Dredze M, Nobles AL. Internet searches for acute anxiety during the early stages of the COVID-19 pandemic. JAMA Intern Med. 2020 doi:10.1001/jamainternmed.2020.3305. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
17. Zitting KM, Lammers-van der Holst HM, Yuan RK, Wang W, Quan SF, Duffy JF. Google trends reveal increases in internet searches for insomnia during the COVID-19 global pandemic. J Clin Sleep Med. 2020 doi:10.5664/jcsm.8810. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
18. Kuhn M, Türp JC. Risk factors for bruxism. Swiss Dent J. 2018;128:118–124. [PubMed] [Google Scholar]
19. Guo H, Wang T, Niu X, Wang H, Yang W, Qiu J, Yang L. The risk factors related to bruxism in children: a systematic review and meta-analysis. Arch Oral Biol. 2018;86:18–34. doi:10.1016/j.archoralbio.2017.11.004. [PubMed] [CrossRef] [Google Scholar]
20. Castroflorio T, Bargellini A, Rossini G, Cugliari G, Deregibus A. Sleep bruxism and related risk factors in adults: a systematic literature review. Arch Oral Biol. 2017;83:25–32. doi:10.1016/j.archoralbio.2017.07.002. [PubMed] [CrossRef] [Google Scholar]
21. Castroflorio T, Bargellini A, Rossini G, Cugliari G, Deregibus A. Sleep bruxism in adolescents: asystematic literature review of related risk factors. Eur J Orthod. 2017;39:61–68. doi:10.1093/ejo/cjw012. [PubMed] [CrossRef] [Google Scholar]
22. Melo G, Duarte J, Pauletto P, Porporatti AL, Stuginski-Barbosa J, Winocur E, Flores-Mir C, De Luca Canto G. Bruxism: an umbrella review of systematic reviews. J Oral Rehabil. 2019;46:666–690. doi:10.1111/joor.12801. [PubMed] [CrossRef] [Google Scholar]
23. Mavragani A, Ochoa G. Google trends in infodemiology and infoveillance: methodology framework. JMIR Public Health Surveill. 2019;5:e13439. doi:10.2196/13439. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
24. Kardeş S. Seasonal variation in the internet searches for gout: an ecological study. Clin Rheumatol. 2019;38:769–775. doi:10.1007/s10067-018-4345-2. [PubMed] [CrossRef] [Google Scholar]
25. Kardeş S. Seasonal variation in the internet searches for psoriasis. Arch Dermatol Res. 2019;311:461–467. doi:10.1007/s00403-019-01921-0. [PubMed] [CrossRef] [Google Scholar]
26. Misra DP, Zimba O, Gasparyan AY. Statistical data presentation: aprimer for rheumatology researchers. Rheumatol Int. 2021;41:43–55. doi:10.1007/s00296-020-04740-z. [PubMed] [CrossRef] [Google Scholar]
27. Rajan A, Sharaf R, Brown RS, Sharaiha RZ, Lebwohl B, Mahadev S. Association of search query interest in gastrointestinal symptoms with COVID-19 diagnosis in the United States: infodemiology study. JMIR Public Health Surveill. 2020;6:e19354. doi:10.2196/19354. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
28. Senecal C, Gulati R, Lerman A. Google trends insights into reduced acute coronary syndrome admissions during the COVID-19 pandemic: infodemiology study. JMIR Cardio. 2020;4:e20426. doi:10.2196/20426. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
29. Walker A, Hopkins C, Surda P. Use of Google trends to investigate loss-of-smell-related searches during the COVID-19 outbreak. Int Forum Allergy Rhinol. 2020;10:839–847. doi:10.1002/alr.22580. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
30. Kardeş S. Public interest in spa therapy during the COVID-19 pandemic: analysis of Google trends data among Turkey. Int J Biometeorol. 2021 doi:10.1007/s00484-021-02077-1. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
31. Kardeş S, Kuzu AS, Pakhchanian H, Raiker R, Karagülle M. Population-level interest in anti-rheumatic drugs in the COVID-19 era: insights from Google trends. Clin Rheumatol. 2020 doi:10.1007/s10067-020-05490-w. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
32. Esen-Salman K, Akın-Çakıcı Ö, Kardeş S, Salman A. Public interest in dermatologic symptoms, conditions, treatments, and procedures during the COVID-19 pandemic: insights from Google trends. Dermatol Ther. 2021;34:e14895. doi:10.1111/dth.14895. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
33. Kardeş S, Kuzu AS, Raiker R, Pakhchanian H, Karagülle M. Public interest in rheumatic diseases and rheumatologist in the United States during the COVID-19 pandemic: evidence from Google trends. Rheumatol Int. 2021;41:329–334. doi:10.1007/s00296-020-04728-9. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
34. Kardeş S, Erdem A, Gürdal H. Public interest in musculoskeletal symptoms and disorders during the COVID-19 pandemic: infodemiology study. Z Rheumatol. 2021 doi:10.1007/s00393-021-00989-2. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
35. Emodi-Perlman A, Eli I, Smardz J, Uziel N, Wieckiewicz G, Gilon E, Grychowska N, Wieckiewicz M. Temporomandibular disorders and Bruxism outbreak as apossible factor of orofacial pain worsening during the COVID-19 pandemic-concomitant research in two countries. J Clin Med. 2020;9:3250. doi:10.3390/jcm9103250. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
36. Javaid A, Yousufi S, Riaz Z, Yasir Y, Tajik I, Ahmad N. A global perspective in self-reported brushing, bruxism and tmd symptoms during COVID-19 lockdown. STETHO. 2021;2:1–9. doi:10.5281/zenodo.4543641. [CrossRef] [Google Scholar]
37. Hassan KA, Khier SE. Awake bruxism intensified during COVID-19 pandemic by cumulative stress—An overview. J Clin Res Dent. 2020;3:1–3. doi:10.33309/2639-8281.030103. [CrossRef] [Google Scholar]
38. Statcounter https://gs.statcounter.com/search-engine-market-share/. Accessed 15 Oct 2020
Articles from Journal of Orofacial Orthopedics are provided here courtesy of Nature Publishing Group
