Search

Objective: This study evaluated whether single nucleotide polymorphisms in the melatonin receptor type 1 A gene are associated with sleep bruxism in a Brazilian population., Design: Individuals with suspected sleep-related problems were evaluated using polysomnography, following the recommendations proposed by the American Academy of Sleep Medicine and the Research Diagnostic Criteria for Temporomandibular Disorders. Deoxyribonucleic acid (DNA) samples were collected, and three single nucleotide polymorphisms in the melatonin receptor type 1 A gene (rs13140012, rs6553010, and rs6847693) were selected and genotyped using real-time polymerase chain reaction (RT-PCR). Chi-square and odds ratio tests were used to analyze genotypes and alleles individually, while using the plink software for haplotypes. A confidence interval of 95% was considered, and statistical significance was set at p < 0.05., Results: This study included 48 individuals aged between 21 and 80 years, with 27 males and 21 females. From this sample, 17 individuals were diagnosed with sleep bruxism and 31 without bruxism. No associations were found between sleep bruxism and single nucleotide polymorphisms in either the genotypic, allelic, dominant, or recessive models (p > 0.05). Haplotype genetic analysis also did not reveal any association between single nucleotide polymorphisms and sleep bruxism (p > 0.05)., Conclusion: The genetic polymorphisms rs6553010, rs13140012, and rs6847693 were not associated with sleep bruxism in the studied population., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: None., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Study Objectives: To evaluate the available evidence on the putative relationships between sleep bruxism (SB) and, obstructive sleep apnea (OSA) to assess the extent of research on this topic, and to formulate suggestions for future research., Methods: A scoping review including studies examining temporal and overall association and prevalence of SB and OSA was performed. Six main databases and gray literature were searched. The studies selection was conducted by three independent reviewers. A narrative synthesis of the results was carried out., Results: Thirteen studies in adults and eight studies in children were finally included. The median of concomitant conditions prevalence was 39.3% in adults and 26.1% in children. Marked methodological variability was identified among studies in adults and even more when we compared detection methods in children. No significant association between OSA and SB emerged in most studies in adults, while an association may be possible in children., Conclusions: Based on the current literature, it is not possible to confirm that there is a relationship between SB and OSA in adults. In patients under pediatric care, although this association seems plausible, there is currently insufficient supportive evidence. Standardized validated methodologies for identifying SB should be consistently used in both populations before reaching any conclusion regarding such association. Furthermore, assessment of shared phenotypes between patients with SB and patients with OSA may reveal new insights that will contribute to personalized approaches aiming to optimize the management of such comorbidities., (© The Author(s) 2022. Published by Oxford University Press on behalf of Sleep Research Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Objective: To evaluate the association of single-nucleotide polymorphisms within the catechol-O-methyltransferase and 5-hydroxytryptamine receptor 2A genes with sleep bruxism in individuals diagnosed with obstructive sleep apnea., Design: Sixty-nine individuals with suspected sleep-related problems were evaluated by polysomnography, following the recommendations of the American Academy of Sleep Medicine. Deoxyribonucleic acid (DNA) samples were collected only from 48 of the study participants because of missing polysomnographic data. DNA samples were collected and two single-nucleotide polymorphisms in the 5-hydroxytryptamine receptor 2A encoding HTR2A gene (rs4941573 and rs6313) and two in the catechol-O-methyltransferase gene (rs165656 and rs174675) were selected to be genotyped using real-time polymerase chain reaction. The association between sleep bruxism and genetic polymorphisms was investigated by recessive and dominant models. Association analyses were performed using a 95% confidence interval and the level of statistical significance was p < 0.05., Results: From the 69 study participants, 48 were included in the polymorphism analysis and sleep bruxism was present in 35.4%. No significant differences were observed in the dominant and recessive models (p > 0.05). Haplotype and diplotype analyses revealed the predicted four haplotypes and two diplotypes were not associated with sleep bruxism., Conclusion: Polymorphisms rs174675 and rs165656 in the catechol-O-methyltransferase gene and rs4941573 and rs6313 in the 5-hydroxytryptamine receptor 2A gene were not significantly associated with sleep bruxism in individuals with obstructive sleep apnea., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

To synthesise and critically review the association between sleep bruxism (SB) and stress symptoms in adults. A systematic review was performed. The search was completed using seven primary electronic databases in addition to a grey literature search. Two reviewers blindly selected studies based on pre-defined eligibility criteria. Risk of bias of the included articles was performed using the Joanna Briggs Institute Critical Appraisal Checklist for Analytical Cross-Sectional Studies. RevMan 5.4 was used to perform the meta-analysis. The quality of evidence was evaluated according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE). Ten studies were included for qualitative analysis, of which three were included for quantitative analysis. Three studies were evaluated to have low risk of bias, and seven were assessed with moderate risk of bias. Quality of evidence was classified as very low for all outcomes. Individuals with SB were found to have higher levels of some self-reported stress symptoms as assessed through questionnaires with a mean difference of 4.59 (95% CI 0.26-8.92). Biomarkers like epinephrine, norepinephrine, cortisol, adrenaline, dopamine, noradrenaline and prolidase enzyme levels also showed a positive association with SB. Although some associations were identified between probable SB and self-reported stress symptoms and biomarkers of stress in adults, given that the quality of evidence was found to be very low, caution should be exercised in interpreting these results. These findings suggest that additional and better designed studies are warranted in order to clarify the link between SB and stress., (© 2021 John Wiley & Sons Ltd.)

Aims: To answer the question: among observational studies, is there any association between primary headaches and bruxism in adults?, Materials and Methods: A systematic review of observational studies was performed. The search was performed in seven main databases and three gray literature databases. Studies in which samples were composed of adult patients were included. Primary headaches were required to be diagnosed by the International Classification of Headache Disorders. Any diagnostic method for bruxism was accepted. Risk of bias was evaluated using the Joanna Briggs Institute Critical Appraisal Tool and the Meta-Analysis of Statistics Assessment and Review Instrument (MAStARI) tool. Associations were analyzed by calculating odds ratios (OR) in Review Manager 5.3 software. The evidence certainty was screened by Grading of Recommendations Assessment, Development, and Evaluation criteria., Results: Of the 544 articles reviewed, 5 met the inclusion criteria for qualitative analysis. The included studies evaluated both awake and sleep bruxism, as well as tension-type headaches and migraines as primary headaches. Among two migraine studies, one showed an OR of 1.79 (95% CI: 0.96 to 3.33) and another 1.97 (95% CI: 1.5 to 2.55). On the other hand, among three tension-type headache studies, there was a positive association only with awake bruxism, with an OR of 5.23 (95% CI: 2.57 to 10.65). All included articles had a positive answer for more than 60% of the risk of bias questions. The evidence certainty varied between low and very low. Due to high heterogeneity among the studies, it was impossible to perform a meta-analysis., Conclusion: Patients with awake bruxism have from 5 to 17 times more chance of having tension-type headaches. Sleep bruxism did not have any association with tension-type headache, and the association with migraines is controversial.

Background: The purpose of this systematic review was to evaluate the association between sleep bruxism (SB) and anxiety symptoms in adults., Methods: A systematic review was performed and studies assessing SB by means of questionnaires, clinical examination and/or polysomnography (PSG), and validated questionnaires to assess anxiety, were included. Search strategies were developed for seven main electronic databases. Risk of bias was assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Analytical Cross-Sectional Studies, and confidence in cumulative evidence was evaluated using the Grading of Recommendations Assessment, Development and Evaluation criteria., Results: Eight cross-sectional studies were included, of which five were judged with low and three with moderate risk of bias. No association with SB was observed in three studies that investigated generic levels of anxiety, while other two papers that evaluated generic anxiety levels through the State-Trait Anxiety Inventory (STAI) found a positive association with probable and definite SB in both STAI-1 and STAI-2 subscales. Only one study evaluated dental anxiety in particular and an association with probable SB was observed regarding very anxious or extremely anxious scores. Two studies assessed specific symptoms of anxiety using the panic-agoraphobic spectra evaluation (PAS-SR) questionnaire. Significantly higher PAS-SR total scores were observed in both studies with regard to SB. No study with definitive assessment of SB was identified., Conclusion: Current literature is controversial regarding an association between SB and generic symptoms of anxiety in adults. It seems that some specific symptoms of the anxiety disorders spectrum might be associated with probable SB., (© 2019 John Wiley & Sons Ltd.)