Temporomandibular Disorders, Bruxism and Headaches.

Temporomandibular disorders (TMDs) and headache disorders are highly prevalent in the population. TMDs can present headache symptoms as a secondary headache and, in addition, be comorbid with primary headache disorders. This overlap has significant clinical implications for which it is essential for the physician to be aware, and they should screen for the potential presence of TMDs in a headache patient. Bruxism is a parafunctional behavior also prevalent in the population which has a role in TMDs and may influence headache symptomatology, but it is still necessary to clarify this relationship.

Physical manifestations of stress in women. Correlations between temporomandibular and pelvic floor disorders.

INTRODUCTION: Stress is characterized as a challenging occurrence that triggers a physiological and/or behavioral allostatic response, alongside the demands typically encountered throughout the natural course of life. A sustained state of stress gives rise to secondary effects, including insomnia and neck pain. Also, the risk of musculoskeletal problems in the cervical and lumbar spine can be increased due to a sustained state of stress. The present study main objective is to study the association between orofacial and pelvic floor muscles in women in Spain. METHODOLOGY: An observational, cross-sectional, retrospective analytical study was designed and carried out in the laboratories of the European University of Madrid. Sixty-five participants were recruited with a mean age of 29.9 ± 7.69. Measurements were taken by myotonometry on natural oscillation frequency (Hz), dynamic stiffness (N/m), elasticity (N/m2), mechanical stress relaxation time (ms) and creep, for the following muscles: right and left masseter, right and left temporalis and central fibrous nucleus of the perineum (CFPF). On the other hand, the subjects completed the following questionnaires: perceived stress scale (PSS-14), anxiety scale (STAI), self-reported bruxism questionnaire (CBA), Fonseca Anamnestic Index and the Pittsburgh Sleep Quality Scale (PSQI). RESULTS: Significant correlations were found in several parameters between the right temporalis and CFPF (p<0.05). Highlighting the correlation between TMDs and lubrication r = -0.254 (p = 0.041) and bruxism with pain in sexual intercourse r = 0.261 (p = 0.036). CONCLUSION: The results support the proposed hypothesis. To the author's knowledge, this is the first study which relates both locations, and it is suggested to continue with the research and expand the knowledge of it.

[Temporomandibular dysfunction and bruxism in patients with early rheumatoid arthritis and at-risk patients: a cross-sectional study]. / Temporomandibulaire disfunctie en bruxisme bij patiënten met vroege reumatoïde artritis en risicopatiënten: een cross-sectioneel onderzoek.

What is the prevalence of temporomandibular dysfunction in patients with early rheumatoid arthritis and individuals at risk of rheumatoid arthritis? 3 groups (of 50 participants each) were examined for a possible TMD diagnosis: 1. patients with early rheumatoid arthritis, 2. at-risk individuals, and 3. healthy controls. A possible association with bruxism, determined on the basis of self-reporting and clinical features, was also examined. At-risk patients had a higher prevalence of TMD pain diagnoses compared to healthy controls (p = 0.046). Within the early rheumatoid arthritis group, seronegative patients had a higher prevalence of TMD pain diagnoses than seropositive patients (p = 0.048). No further differences in the prevalence of TMD diagnoses were found between the groups. Participants with a TMD pain diagnosis were more often diagnosed with probable sleep bruxism than those without a TMD pain diagnosis. The prevalence of TMD pain is increased in individuals at risk of rheumatoid arthritis and seronegative early rheumatoid arthritis patients, and is associated with signs of bruxism.

Recurrence of exostosis as a result of medication-induced bruxism: case study.

Introduction: Alveolar oral exostosis is a common, benign condition routinely found in dentistry. Clinical problems associated with exostoses are the maintenance of oral hygiene as well as the fabrication of prosthodontic appliances. Over time, exostoses may contribute to irritation and periodontal disease. Case description: The patient in this case study had a recurrence of exostoses and was bothered by consistent and prominent pain. She reported being a bruxer; her bruxism was exacerbated due to attention-deficit hyperactivity disorder and antidepressant medications. Discussion: The etiology behind the recurrence of exostosis is discussed. The most evident etiology seems to be persistence of medication-induced bruxism, specifically awake bruxism. Conclusion: It is necessary to take a proper history to identify the cause of the recurrence of exostosis. Dental hygienists can contribute to a better understanding of and provide better treatment options for patients who have medication-induced bruxism.

Introduction: L'exostose buccale alvéolaire est une affection bénigne courante couramment observée en dentisterie. Les problèmes cliniques associés aux exostoses sont le maintien de l'hygiène buccale ainsi que la fabrication d'appareils prosthodontiques. Avec le temps, les exostoses peuvent causer de l'irritation et des maladies parodontales. Description de cas: Dans cette étude de cas, la patiente présente des exostoses récurrentes et est dérangée par une douleur constante et proéminente. Elle a déclaré souffrir de bruxisme exacerbé par la prise de médicaments antidépresseurs et contre le trouble déficitaire de l'attention avec hyperactivité. Discussion: L'étiologie derrière la récurrence de l'exostose est abordée. L'étiologie la plus évidente semble être la persistance du bruxisme induit par les médicaments, en particulier le bruxisme diurne. Conclusion: Il est nécessaire d'obtenir les antécédents médicaux appropriés pour identifier la cause de la récurrence de l'exostose. Les hygiénistes dentaires peuvent contribuer à une meilleure compréhension et offrir de meilleures options de traitement aux patients atteints de bruxisme induit par les médicaments.

Temporomandibular disorders and bruxism - up-to-date assessment and screening tools the general dentist should be aware of.

The recently proposed shortened screening tools for temporomandibular disorders (TMD) and bruxism should enable a better assessment of these conditions by the general dentist.

An epidemiological qualitative/quantitative SWOT-AHP analysis in order to highlight the positive or critical aspects of dental implants: A pilot study.

OBJECTIVES: In recent years, dental implants are increasing in popularity due to their high success rate, demonstrated functionality, and aesthetic treatment results. Scientific research is very active in proposing improvements in the quality and survival of implants, taking into consideration various aspects. The objective of this study was to provide a holistic epidemiologic view of the state of dental implants, using a systematic approach based on a multimethod SWOT (Strengths, Weaknesses, Opportunities, and Threats) analysis and AHP (analytical hierarchical process) qualitative-quantitative analysis to identify the characteristics that can determine their success or failure. MATERIALS AND METHODS: The study used the hybrid method of SWOT-AHP. RESULTS: Analysis of the results showed that among strengths, the skill of the dentist was considered the most important factor, followed by the success of dental implants in the old people; among weaknesses, bruxism and chronic diseases were highlighted; for opportunities, biomechanical behavior, in terms of good mechanical strength and good tribological resistance to chemical and physical agents in the oral cavity, were considered the most important factors; finally, among threats, medical liability and biomechanical problems had equal weight. CONCLUSIONS: This study applied a multimethod SWOT-AHP approach to bring out favorable or critical evidence on the topic of dental implants. In accordance with the result of the strategic vector identified in the Twisting zone Adjustment type section, showed that implant surgery is a widespread technique but always needs improvement to increase the likelihood of success and reduce the complications that can lead to implant failure.

Comparison of ultrasonography-based masticatory muscle thickness between temporomandibular disorders bruxers and temporomandibular disorders non-bruxers.

To compare masticatory muscle thickness in patients with temporomandibular disorders (TMDs) during rest and clenching, and by body position, using ultrasonography. This prospective study included 96 patients with TMD (67 females, 29 males; mean age: 40.41 ± 17.88 years): group 1, comprising 66 patients with TMD without bruxism (TMD_nonbruxer), and group 2, comprising 30 patients with concurrent TMD and bruxism (TMD_bruxer). In patients with TMD, bruxism was correlated with the presence of tinnitus, muscle stiffness, sleep problems, psychological stress, and restricted mouth opening. The masseter muscle significantly thickened during clenching (11.16 ± 3.03 mm vs 14.04 ± 3.47 mm, p < 0.001), whereas the temporalis muscle showed no significant increase in thickness from resting to clenching in an upright position (7.91 ± 1.98 vs 8.39 ± 2.08, p = 0.103). Similarly, during clenching in the supine position, the masseter muscle was significantly thicker compared with rest (11.24 ± 2.42 vs 13.49 ± 3.09, p < 0.001), but no significant difference was observed in temporal muscle thickness (8.21 ± 2.16 vs 8.43 ± 1.94, p = 0.464). In comparison between two groups, the average thickness of the masseter muscle was greater among TMD_bruxers than among TMD_nonbruxers in both the upright and supine positions (all p < 0.05). In the generalized lineal model, female sex (B = - 1.018, 95% confidence interval [CI] - 1.855 to - 0.181, p = 0.017) and bruxism (B = 0.868, 95% CI 0.567 to 1.169, p = 0.048) significantly predicted changes in masseter muscle thickness. Female sex (B = - 0.201, 95% CI - 0.299 to - 0.103, p = 0.011), increased age (B = - 0.003, 95% CI - 0.005 to 0.000, p = 0.038), and muscle stiffness (B = - 1.373, 95% CI - 2.369 to - 0.376, p = 0.007) were linked to decreased temporal muscle thickness. Comparing TMD nonbruxer and bruxer muscle thicknesses in upright and supine positions revealed significant increased thickness in the masseter muscle during clenching but not in the temporalis muscle. Masseter muscle thickness varied significantly by sex, body position, and resting/clenching, notably influenced by bruxism. These findings emphasize the relevance of these factors in clinical examinations of patients with TMD.

The effectiveness of botulinum toxin for temporomandibular disorders: A systematic review and meta-analysis.

OBJECTIVE: The current body of research on utilizing botulinum toxin (BTX) to manage temporomandibular disorders (TMDs) has not yet yielded definitive conclusions. The primary objective of this study was to determine the effectiveness of BTX in pain reduction for TMDs compared to placebo and other treatments. The secondary outcomes evaluated were adverse events, maximum mouth opening, bruxism events, and maximum occlusal force. MATERIALS AND METHODS: A literature search was performed on PubMed, Dimension Publication, Scopus, and Google Scholar. The RoB 2 tool was used for quality assessment. The mean differences in pain scores were estimated to measure the effect of BTX on pain reduction. For adverse events, the risk ratio for the incidence of side effects was calculated. RESULTS: Two hundred and sixty non-duplicate articles were identified; however, only 14 RCTS were included in this review. The total study population included 395 patients. The overall risk of bias showed a low to moderate quality of evidence. Results from 6 studies were reported only narratively; four studies were used for meta-analysis on pain reduction, and five were used for meta-analysis on adverse events. The control used in the meta-analysis was placebo injections. Results of the meta-analysis for pain reduction were statistically insignificant for the BTX group with mean differences at MD = -1.71 (95% CI, -2.87 to -0.5) at one month, -1.53 (95% CI, -2.80 to -0.27) at three months, and -1.33 (95% CI, -2.74 to 0.77) at six months. This showed that BTX treatment was not significantly better than placebo for a reduction in pain scores at 1, 3, and 6 months. Regarding safety, the placebo group showed a relative risk of 1.34 (95%CI, 0.48-6.78) and 1.17 (95%CI, 0.54-3.88) at 1 and 3 months respectively. However, the risks were not statistically significant. There was also no difference in the effectiveness of BTX compared to placebo and other treatments for maximum mouth opening, bruxism events, and maximum occlusal force. CONCLUSION: BTX was not associated with better outcomes in terms of pain reduction, adverse events, maximum mouth opening, bruxism events, and maximum occlusal force. More high-quality RCTs are needed to better understand this topic.

Sixty-month comperative evaluation of a glass hybrid restorative and a composite resin in non-carious cervical lesions of bruxist individuals.

OBJECTIVE: To compare the clinical performance of a glass hybrid (GH) restorative and a nano-ceramic composite resin (CR) in the restoration of non-carious cervical lesions (NCCLs) of bruxist individuals in a 60-month randomized clinical trial. MATERIALS AND METHODS: Twenty-five bruxist candidates having NCCLs were recruited in this clinical study. The depth, height (cervico-incisal), width (mesio-distal), internal angles of the NCCLs, degree of tooth wear (TWI) and gingival index (GI) were measured. One hundred-and-forty-eight NCCLs were restored either with a GH restorative (Equia Forte Fil) or a CR (Ceram.X One Universal). Modified USPHS criteria was used to evaluate restorations after 1 week and 12, 24, 36 and 60 months. Pearson's Chi-Square, Fisher's Exact and Cochran Q tests were run for analysis. Survival rates of the restorations were compared with Kaplan-Meier analysis (p < 0.05). RESULTS: After 60 months, 97 restorations in 15 patients were examined. The recall rate was 60.0%. Retention rates were 73.5% for CR and 66.7% for GH. A total of 29 restorations were lost (13CR (26.5%), 16GH (33.3%)). There was not a significant difference between tested restoratives in retention (p = 0.464), marginal adaptation (p = 0.856) and marginal discoloration (p = 0.273). There was no relationship between internal angle, depth, height or width and retention of the GH or CR restorations (p > 0.05). The increase in retention loss and marginal discoloration of both restorations over time were significant (p < 0.001). Sensitivity or secondary caries were not detected after 60 months. CONCLUSION: GH and nano-ceramic CR showed similar clinical performances in NCCLs after 60 months in patients with bruxism. CLINICAL SIGNIFICANCE: After 60 months, CR and GH materials showed clinically acceptable performances in restoration of NCCLs in patients with bruxism.

The survival of periodontally treated molars in long-term maintenance: A systematic review and meta-analysis.

AIM: This systematic review and meta-analysis aimed to determine the survival of periodontally treated molars during maintenance care and identify the risk factors associated with molar loss among patients with periodontitis who received professional periodontal therapy and maintenance. MATERIALS AND METHODS: Longitudinal studies with a minimum follow-up duration of 5 years published until 28 August 2023 were retrieved from the following databases: the Cochrane Library, Embase, MEDLINE and Web of Science. All included studies reported data on molar retention. Meta-analysis was performed using Review Manager 5.4. A modified version of the Newcastle-Ottawa Scale was used to evaluate the study quality. Statistical results of analyses of the overall survival rate and molar loss are presented as estimated standardized mean differences, whereas the results of the analyses of risk factors are presented as risk ratios with 95% confidence intervals (95% CIs). RESULTS: From among the 1323 potentially eligible reports, 41 studies (5584 patients, 29,908 molars retained at the beginning of maintenance therapy, mean follow-up duration of 14.7 years) were included. The pooled survival rate of the molars during maintenance therapy was 82% (95% CI: 80%-84%). The average loss of molars was 0.05 per patient per year (95% CI: 0.04-0.06) among the patients receiving long-term periodontal maintenance (PM) therapy. Fifteen factors were examined in this meta-analysis. Six patient-related factors (older age, lack of compliance, smoking, bruxism, diabetes and lack of private insurance) and five tooth-related factors (maxillary location, high probing pocket depth, furcation involvement, higher mobility and lack of pulpal vitality) were identified as risk factors for molar loss during maintenance therapy. CONCLUSIONS: The findings of the present study suggest that the long-term retention of periodontally compromised molars can be achieved. The average number of molars lost per decade was <1 among the patients receiving long-term PM therapy. Older age, noncompliance, smoking, bruxism, diabetes, lack of private insurance coverage, maxillary location, furcation involvement, higher mobility, increase in the probing pocket depth and loss of pulpal vitality are strong risk factors for the long-term prognosis of molars.

Investigation of masticatory muscle thickness and mechanosensitivity of cervical and masticatory muscles in myofascial temporomandibular disorder patients with bruxism: A cross-sectional study.

OBJECTIVE: Bruxism is a common problem associated with temporomandibular disorders (TMD). The aim of this study was to compare a patient group with Myofascial TMD and bruxism and a healthy control group in terms of masseter and temporal muscle thickness (clenching and resting), mechanosensitivity of neck and jaw muscles, craniofacial pain, and disability and emotional stress status. METHODS: The study included 31 patients with myofascial TMD and bruxism (19 females, 12 males) with a mean age of 29.96 ± 8.12 years (range, 18-45 years), and a control group of 31 healthy subjects (19 females, 12 males) with a mean age of 27.58 ± 9.39 years years (range, 18-45 years). Masseter and temporal muscle thicknesses were evaluated with a mobile ultrasound device both at rest and when clenching the jaw. The mechanosensitivity values between the upper trapezius, obliquus capitis inferior, masseter and temporal muscles were measured with a digital algometer device. Craniofacial pain and disability level were evaluated with the Craniofacial Pain and Disability Index (CFPDI), and emotional stress levels with the Perceived Stress Scale-14 (PSS-14). RESULTS: No difference was determined between the two groups in respect of the clenching and resting ratios of muscle thickness in any muscle (p > 0.05). The mechanosensitivity values in all muscles were lower in the myofascial TMD group than in the healthy group (p < 0.05). The CFPDI and PSS-14 scores were higher in the myofascial TMD group (p < 0.05). There was a moderate positive correlation between CFPDI, PSS-14 and Bruxism Frequency Score (p < 0.05). CONCLUSION: The difference in mechanosensitivity and CFPDI values between the myofascial TMD patients with bruxism and the healthy control group indicates that the problem in this patient group has effects in the craniocervical and cervical regions. In addition, the correlation between CFPDI, PSS-14 and Bruxism Frequency Score in myofascial TMD patients suggests that this problem may be affected by the interaction of different parameters.

Autistic individuals have worse oral status than neurotypical controls: a systematic review and meta-analysis of observational studies.

OBJECTIVE: To compare dental caries, oral hygiene, periodontal status, bruxism, malocclusion, tooth loss, and salivary alterations between autistic and typical developing individuals. MATERIAL AND METHODS: Observational studies presenting clinical measures of oral outcomes between autism spectrum disorder (ASD) individuals and controls. EMBASE, LILACS, PubMed, PsycINFO, Scopus, Web of Science, Google Scholar, and ProQuest were searched up to June 26, 2023. Pairs of reviewers independently conducted study selection, data extraction, and assessments of methodological quality and certainty of evidence. Meta-analyses of standardized mean differences (SMD) and risk ratio (RR) were performed. RESULTS: A total of 47 studies comprising 6885 autistic individuals were included in the review. Autistic individuals had significantly higher severity of dental-caries experience in primary teeth (SMD 0.29, 95%CI 0.02, 0.56), of dental plaque presence (SMD 0.59, 95%CI 0.24, 0.94), and of gingivitis (SMD 0.45, 95%CI 0.02, 0.88). Autistic individuals showed higher probability of occurrence of gingivitis (RR 1.34, 95%CI 1.08, 1.66,), bruxism (RR 4.23, 95%CI 2.32, 7.74), overjet (RR 2.16, 95%CI 1.28, 3.64), overbite (RR 1.62, 95%CI 1.02, 2.59), crossbite (RR 1.48, 95%CI 1.02, 2.13), and openbite (RR 2.37, 95%CI 1.46, 3.85), when compared to neurotypical individuals. Most estimates showed a small effect size with very low certainty of evidence. CONCLUSION: Autistic individuals show worse oral health status than controls. CLINICAL RELEVANCE: The findings reported herein can help to build health policies to better serve autistic individuals including prevention actions and access to specialized dental care.

Influence of malocclusion on sleep bruxism and orofacial pain: data from a study in school children.

OBJECTIVES: This cross-sectional school-based study explored the influence of malocclusion on temporomandibular disorders (TMD) pain complaints, and whether this association would be mediated by sleep bruxism in a representative sample of 7- to 8-year-old children. METHODS: Path analysis estimated direct, indirect, and total effects of occlusal features on sleep bruxism and TMD pain in 7- to 8-year-old children. Occlusal features were assessed with Dental Aesthetic Index (DAI), orofacial pain complaints using the TMD pain screener, possible sleep bruxism based on self-reports, and probable sleep bruxism based on self-reports combined with clinical findings. Structural equation modeling analyzed data with confounding factors. RESULTS: From 580 participants, possible sleep bruxism was observed in 136 children (31.5%), probable sleep bruxism in 30 children (6.7%), and TMD pain complaints in 78 children (13.8%). Malocclusion had no direct effect on either possible sleep bruxism [standardized coefficient (SC) 0.000; p = 0.992], or TMD pain complaints (SC - 0.01; p = 0.740). When probable sleep bruxism was set as the mediator of interest, malocclusion did not directly affect probable sleep bruxism (SC 0.01; p = 0.766), nor TMD pain complaints (SC - 0.02; p = 0.515). A direct effect of probable sleep bruxism on TMD pain complaints was observed with an SC of 0.60 (p < 0.001). However, in neither case, malocclusion indirectly affected TMD pain complaints via bruxism. CONCLUSION: Malocclusion in 7- to 8-year-old children did not directly influence possible or probable sleep bruxism or TMD pain complaints. Instead, probable sleep bruxism was strongly associated with TMD pain complaints. CLINICAL SIGNIFICANCE: The impact of occlusal features on TMD pain complaints and bruxism has been a long-standing controversy in dentistry. However, the scientific literature linking this association may be inconsistent, mainly due to biased sample selection methods with inadequate consideration of confounders. Further research should try to identify additional risk factors for TMD pain in addition to probable sleep bruxism in children.

Self-reported bruxism in patients with post-traumatic stress disorder.

OBJECTIVE: The present study aimed to investigate the association between self-reported awake/sleep bruxism, and orofacial pain with post-traumatic stress disorder (PTSD). METHODS: A case-control study with a convenience sample was designed. Participants were recruited from a university-based Trauma Ambulatory. The diagnosis of PTSD was established through a clinical interview and the Structured Clinical Interview (SCID-I/P). Thirty-eight PTSD patients and 38 controls completed the Research Diagnostic Criteria for Temporomandibular Disorders Axis-II to categorize awake/sleep bruxism and orofacial pain. Following this, we performed a short clinical examination of the temporomandibular joint and extraoral muscles. RESULTS: Adjusted logistic regression analysis showed that awake bruxism was associated with PTSD (OR = 3.38, 95% CI = 1.01-11.27, p = 0.047). Sleep bruxism was not associated with any covariate included in the model. In a Poisson regression model, PTSD (IRR = 3.01, 95% CI = 1.38-6.55, p = 0.005) and the muscle pain/discomfort (IRR = 5.12, 95% CI = 2.80-9.36, p < 0.001) were significant predictors for current orofacial pain. CONCLUSIONS: PTSD was associated with self-reported awake bruxism and low-intensity orofacial pain. These conditions were frequent outcomes in patients previously exposed to traumatic events. CLINICAL RELEVANCE: We suggest including a two-question screening for bruxism in psychiatry/psychology interviews to improve under-identification and to prevent harmful consequences at the orofacial level.

Psychological distress and the belief that oral behaviours put a strain on the masticatory system in relation to the self-report of awake bruxism: Four scenarios.

BACKGROUND: It is assumed that other factors than masticatory muscle activity awareness could drive the self-report of awake bruxism. OBJECTIVES: To investigate the extent to which the report of awake bruxism is associated with psychological distress, and with the belief that oral behaviours put a strain on the masticatory system among TMD-pain patients. MATERIALS AND METHODS: The study sample consisted of 1830 adult patients with reported function-dependent TMD pain. Awake bruxism was assessed through six items of the Oral Behaviors Checklist. Psychological distress was assessed by means of somatic symptoms, depression and anxiety. Causal attribution belief was measured with the question 'Do you think these behaviours put a strain on your jaws, jaw muscles, and/or teeth?' RESULTS: Mean age of all participants was 42.8 (±15.2) years, 78.2% being female. Controlled for sex, positive, yet weak, correlations were found between awake bruxism and somatic symptom severity (rs = 0.258; p < .001), depression (rs = 0.272; p < .001) and anxiety (rs = 0.314; p < .001): patients with the highest scores reported approximately twice as much awake bruxism compared to those with minimal scores. Controlled for age and sex, a positive, moderate correlation was found between awake bruxism and causal attribution belief (rs = 0.538; p < .001). Patients who believed that performing awake oral behaviours put 'very much' a strain on the masticatory system reported four times more awake bruxism than patients who did not believe that these behaviours are harmful. CONCLUSIONS: Based on the results and relevant scientific literature, the theoretical background mechanisms of our findings are discussed in four scenarios that are either in favour of the use of self-report of awake bruxism being a representation of masticatory muscle activity awareness, or against it.

Assessment of awake bruxism by a novel bruxism screener and ecological momentary assessment among patients with masticatory muscle myalgia and healthy controls.

BACKGROUND: Bruxism is a masticatory muscle activity occurring during sleep or wakefulness, involving grinding and clenching of teeth and/or jaw bracing. As yet, the aetiology, epidemiology and consequences of awake bruxism (AB) are largely unknown. OBJECTIVES: The aims of the study were to AB behaviours using a novel bruxism screener (BruxScreen) questionnaire part and Ecological Momentary Assessment (EMA; BruxApp©) on AB behaviours, and to investigate AB's prevalence among masticatory muscle myalgia patients and non-patients. METHODS: Altogether, 115 participants (masticatory myalgia patients referred to a specialist clinic (n = 67) and non-patients (n = 46)) filled in a bruxism screener questionnaire to report bruxism behaviours and jaw symptoms. A selection of both groups did a week-long EMA (patients n = 12, non-patients n = 11) to report AB behaviours. The chi-squared test was used to determine group differences in categorical variables. A logistic regression model was fitted to study the probability of AB. RESULTS: According to BruxScreen, bruxism behaviours and jaw symptoms were more frequent in patients than in non-patients (p < .001). Based on EMA, 14.6% of the behaviour in patients was tooth clenching; for non-patients, this was 0.5% (p < .000). Relaxed muscles were reported by patients and non-patients at 20.6% and 56.4%, respectively (p < .021). Logistic regression, adjusted by age and sex, revealed that patients reported AB 5 times more often than non-patients (OR 4.8, 95% CI 2.1-11.2). CONCLUSION: Awake bruxism behaviours are significantly more frequent in masticatory muscle myalgia patients than non-patients and associate with frequent bruxism-related symptoms. Self-reported teeth clenching seems to be the most significant sign of AB behaviour.

Assessment of awake bruxism-Combinational analysis of ecological momentary assessment and electromyography.

PURPOSE: No consensus exists regarding the examination methods and assessment criteria for awake bruxism (AB). In this study, masticatory muscle activity measured using electromyography (EMG) was recorded simultaneously with the ecological momentary assessment (EMA) of bruxism events. Data were collected to identify distinctive EMG parameters in AB. METHODS: A total of 104 individuals were classified into the bruxism (BR) or control (CO) groups based on clinical findings. The participants recorded EMA on a tablet device under continuous EMG recording using a data log-type wireless EMG device. For EMA recording, a warning was randomly provided three times each hour for five hours. A receiver operating characteristic (ROC) curve was obtained based on EMA and EMG events. Maximum voluntary contraction (MVC) at the time of maximum bite force was set at 100%. The muscle activity was assessed as a relative value. RESULTS: Based on discriminant analysis, analysis of participants who had four or more positive clenching EMA responses was appropriate. The assessed parameters for the EMG cutoff value determination procedure, which combined EMG and EMA, resulted in a cutoff value that enabled the distinction between the BR and CO groups. The area under the ROC curve was 0.77 and the cut-off value was 3.2 events/hour under the EMG of 20% MVC with a duration of ≥1 s. CONCLUSIONS: This is the first study to report a combined analysis of the EMA and EMG. These results suggest its effectiveness as a cutoff value for AB screening.

Research routes on awake bruxism metrics: Implications of the updated bruxism definition and evaluation strategies.

BACKGROUND: With time, due to the poor knowledge on it epidemiology, the need to focus on awake bruxism as a complement of sleep studies emerged. OBJECTIVE: In line with a similar recent proposal for sleep bruxism (SB), defining clinically oriented research routes to implement knowledge on awake bruxism (AB) metrics is important for an enhanced comprehension of the full bruxism spectrum, that is better assessment and more efficient management. METHODS: We summarised current strategies for AB assessment and proposed a research route for improving its metrics. RESULTS: Most of the literature focuses on bruxism in general or SB in particular, whilst knowledge on AB is generally fragmental. Assessment can be based on non-instrumental or instrumental approaches. The former include self-report (questionnaires, oral history) and clinical examination, whilst the latter include electromyography (EMG) of jaw muscles during wakefulness as well as the technology-enhanced ecological momentary assesment (EMA). Phenotyping of different AB activities should be the target of a research task force. In the absence of available data on the frequency and intensity of wake-time bruxism-type masticatory muscle activity, any speculation about the identification of thresholds and criteria to identify bruxers is premature. Research routes in the field must focus on the improvement of data reliability and validity. CONCLUSIONS: Probing deeper into the study of AB metrics is a fundamental step to assist clinicians in preventing and managing the putative consequences at the individual level. The present manuscript proposes some possible research routes to advance current knowledge. At different levels, instrumentally based and subject-based information must be gathered in a universally accepted standardised approach.

Occurrence, presence and severity of bruxism and its association with altered state of consciousness in individuals with severe acquired brain injury.

BACKGROUND: Excessive jaw muscle activity is a frequent complication after acquired brain injury (ABI). OBJECTIVE: The study aimed to identify the occurrence and severity of jaw muscle activity and its association with altered state of consciousness in patients with ABI. METHODS: A total of 14 severe ABI patients with varied altered state of consciousness were recruited. A single-channel electromyographic (EMG) device was used to assess the jaw muscle activity for three consecutive nights during Week 1 and Week 4 following admission. Differences in number of EMG episodes/h between Week 1 and 4 were analysed using non-parametric tests and association between the EMG activity and altered state of consciousness were analysed using Spearman's correlation test. RESULTS: Nine of fourteen (64%) patients showed indications of bruxism (cutoff: >15 EMG episodes/h). The average EMG episodes/h at admission were 44.5 ± 13.6 with no significant changes after Week 4 of admission (43 ± 12.9; p = .917). The EMG episodes/h ranged from 2 to 184 during Week 1 and 4-154 during Week 4. There were no significant correlations between the number of EMG episodes/h during the three nights and the individuals altered state of consciousness during Week 1 and Week 4. CONCLUSION: Patients with ABI had a conspicuously high but variable level of jaw muscle activity at admission and it tend to remain high after 4 week of hospitalisation which could potentially lead to adverse effects such as excessive tooth wear, headaches and pain in jaw muscles. The lack of associations between individuals altered level of consciousness and EMG activity could be due to low sample size and further studies are clearly warranted in this patient group with special needs. Single-channel EMG devices can record jaw muscle activity early in the hospitalisation period and might be a helpful tools for early detection of bruxism in ABI patients.