To what extent is bruxism associated with musculoskeletal signs and symptoms? A systematic review

Bruxism, temporomandibular disorders, and headache-a narrative review of correlations and causalities

ABSTRACT

The co-occurrence of bruxism, temporomandibular disorders (TMDs), and headache is common in patients. However, there is conflicting evidence regarding whether this association is simply a result of their high prevalence or whether there are indeed causal relationships. This review provides an overview of the current state of research while taking into account the controversies surrounding research methods, particularly in definitions and diagnostic standards. Bruxism-defined as repetitive jaw muscle activity during sleep or wakefulness-is not a painful disorder but may-particularly in co-occurrence with TMD-worsen pre-existing headache. It seems important to differentiate between sleep and awake bruxism because of different impact on pathophysiological processes in different primary headache disorders such as migraine and tension-type headache. Temporomandibular disorder is a heterogenous entity with both myofascial and arthrogenous types of pain in addition to nonpainful disorders. Research suggests a correlation between TMD pain and migraine, as well as between awake bruxism and tension-type headache. However, psychosocial factors may act as confounders in these relationships. Determining causality is challenging because of the limited number of experimental and clinical studies conducted on this topic. The main finding is an apparent lack of consensus on the definition and assessment criteria for bruxism. Treatment wise, it is important to differentiate all 3 conditions because treatment of one condition may have an effect on the other 2 without proving causality. For future research, it is crucial to establish greater consistency and applicability in diagnostic procedures and definitions. In addition, more experimental and clinical studies investigating the question of causality are needed.

Prevalence of temporomandibular disorders and their associated factors in Confucian heritage cultures: A systematic review and meta-analysis

BACKGROUND

Temporomandibular disorders (TMDs) may be an 'idiom' of psychological distress in Confucian heritage cultures (CHCs).

OBJECTIVES

This systematic review/meta-analysis estimated the prevalence of TMDs in CHCs and compared the differences in TMD occurrence between time periods and age groups. Additionally, the associated biopsychosocial risk factors were also examined.

METHODS

The study protocol was developed a priori following the PRISMA guidelines and Joanna Briggs Institute systematic review methodology (CRD42021245526). Electronic searches of seven databases were conducted from January 2002 to Dec 2021. Reference lists of identified studies were hand-searched for additional articles. Study selection, quality assessment, and data extraction were done. Meta-analysis was performed using the RevMan 5.4 software.

RESULTS

Forty-eight articles were included in the systematic review. Overall prevalences were: TMDs-15% (95% CI: 15-16%); TMD pain-8% (95% CI: 7-9%); TMJ sounds-24% (95% CI: 21-27%); and TMJ locking-7% (95% CI: 1-13%). While TMD prevalence appeared to have declined from 2002 to 2011 to 2012-2021, the occurrence of TMD pain, TMJ sounds, and locking increased marginally or remained constant. TMD prevalence in children/adolescents was 18% (95% CI: 14-22%) and 17% (95% CI: 16-18%) among adults. Significant associations between TMDs and bruxism/psychological distress/education levels were specified by 73%/90%/88% of the relevant studies.

CONCLUSIONS

TMDs are prevalent in CHCs and a slight increase in TMD pain (2%) and TMJ sounds (8%) were discerned over the past two decades. TMDs are related to a myriad of biopsychosocial variables, particularly psychological distress, and these factors must be addressed within the cultural context of patients.

Tooth wear and bruxism: A scoping review

OBJECTIVE

This study presents a scoping review to determine the association between tooth wear and bruxism.

DATA

A protocol was developed a priori (Open Science Framework (DOI 10.17605/OSF.IO/CS7JX)). Established scoping review methods were used for screening, data extraction, and synthesis. Risk of bias was assessed using JBI tools. Direct associations between tooth wear and bruxism were assessed.

SOURCES

Embase, SCOPUS, Web of Science, Cochrane, and PubMed were searched.

STUDY SELECTION

Any clinical study containing tooth wear and bruxism assessment done on humans in any language was included. Animal, in-vitro studies and case reports were excluded.

CONCLUSIONS

Thirty publications reporting on the association between tooth wear and bruxism were included. The majority of publications were cross-sectional studies (90%) while only three were longitudinal (10%). Eleven papers assessed definitive bruxism for analysis (instrumental tools), one paper assessed probable bruxism (clinical inspection with self-report) and eighteen assessed possible bruxism (self-report). Of the eleven papers assessing definitive bruxism, eight also reported outcomes of non-instrumental tools. Tooth wear was mostly scored using indexes. Most studies reported no or weak associations between tooth wear and bruxism, except for the studies done on cervical tooth wear. When bruxism assessment was done through self-report, more often an association was found. Studies using multivariate analyses did not find an association between tooth wear and bruxism, except the cervical wear studies. Evidence shows inconclusive results as to whether bruxism and tooth wear are related or not. Therefore, well-designed longitudinal trials are needed to address this gap in the literature.

CLINICAL SIGNIFICANCE

Based on the evidence, dental clinicians should not infer bruxism activity solely on the presence of tooth wear.

Sleeping and waking-state oral behaviors in TMD patients: their correlates with jaw functional limitation and psychological distress

OBJECTIVES

This study investigated oral behaviors in various temporomandibular disorder (TMD) subtypes, assessing their frequency, extent, and associations with both jaw functional status and psychological distress.

MATERIALS AND METHODS

Anonymized data from consecutive "initial-visit" TMD patients at a university-affiliated oral medicine clinic were obtained. Alongside demographic information, patients completed various questionnaires including the Diagnostic Criteria for TMD (DC/TMD) Symptom Questionnaire, Oral Behavior Checklist (OBC), Jaw Functional Limitation Scale-20 (JFLS-20), Patient Health Questionnaire-9 (PHQ-9), and General Anxiety Disorder Scale-7 (GAD-7). Patients underwent a protocolized clinical examination and received diagnoses of pain-related (PT), intra-articular (IT), or combined (CT) TMD using the DC/TMD diagnostic algorithms. Data were evaluated with Chi-square/non-parametric tests and logistic regression analyses (α = 0.05).

RESULTS

The study comprised 700 patients (mean age 37.4 ± 15.7 years), with 12.6%, 15.1%, and 72.3% diagnosed with PT, IT, and CT, respectively. For all TMD subtypes, oral activities during sleep were more prevalent than those during wakefulness. While variations in total/subscale OBC scores were insignificant, substantial differences were observed in global/subscale JFLS (PT, CT > IT), depression (PT, CT > IT), and anxiety (CT > IT) scores. Near-moderate correlations (rs = 0,36-0.39) were discerned between overall/waking-state non-functional oral behaviors and depression/anxiety. Multivariate analysis indicated that the odds of different TMD subtypes were influenced by sex, age, and jaw functional status.

CONCLUSIONS

For all TMD patients, sleep-related oral activities were more commonly reported than waking-state activities. Factors such as sex, age, and jaw functional limitation are associated with the likelihood of different TMD subtypes.

STATEMENT OF CLINICAL RELEVANCE

Oral behaviors, in themselves, do not predict distinct TMD subtypes, in contrast to factors such as sex, age, and jaw functional status.

Is sleep bruxism in obstructive sleep apnea only an oral health related problem?

BACKGROUND

The etiology of sleep bruxism in obstructive sleep apnea (OSA) patients is not yet fully clarified. This prospective clinical study aimed to investigate the connection between probable sleep bruxism, electromyographic muscle tone, and respiratory sleep patterns recorded during polysomnography.

METHODS

106 patients with OSA (74 males, 31 females, mean age: 56.1 ± 11.4 years) were divided into two groups (sleep bruxism: SB; no sleep bruxism: NSB). Probable SB were based on the AASM criteria: self-report of clenching/grinding, orofacial symptoms upon awakening, abnormal tooth wear and hypertrophy of the masseter muscle. Both groups underwent clinical examination for painful muscle symptoms aligned with Temporomandibular Disorders Diagnostic Criteria (DC/TMD), such as myalgia, myofascial pain, and headache attributed to temporomandibular disorder. Additionally, non-complaint positive muscle palpation and orofacial-related limitations (Jaw Functional Limited Scale-20: JFLS-20) were assessed. A one-night polysomnography with electromyographic masseter muscle tone (EMG) measurement was performed. Descriptive data, inter-group comparisons and multivariate logistic regression were calculated.

RESULTS

OSA patients had a 37.1% prevalence of SB. EMG muscle tone (N1-N3, REM; P = 0.001) and the number of hypopneas (P = 0.042) were significantly higher in the sleep bruxism group. While measures like apnea-hypopnea-index (AHI), respiratory-disturbance-index (RDI), apnea index (AI), hypopnea-index (HI), number of arousals, and heart rate (1/min) were elevated in sleep bruxers, the differences were not statistically significant. There was no difference in sleep efficiency (SE; P = 0.403). Non-complaint masseter muscle palpation (61.5%; P = 0.015) and myalgia (41%; P = 0.010) were significant higher in SB patients. Multivariate logistic regression showed a significant contribution of EMG muscle tone and JFLS-20 to bruxism risk.

CONCLUSION

Increased EMG muscle tone and orofacial limitations can predict sleep bruxism in OSA patients. Besides, SB patients suffer more from sleep disorder breathing. Thus, sleep bruxism seems to be not only an oral health related problem in obstructive apnea. Consequently, interdisciplinary interventions are crucial for effectively treating these patients.

TRIAL REGISTRATION

The study was approved by the Ethics Committee of Philipps-University Marburg (reg. no. 13/22-2022) and registered at the "German Clinical Trial Register, DRKS" (DRKS0002959).

Could painful temporomandibular disorders be nociplastic in nature? A critical review and new proposal

Classification of temporomandibular disorders (TMD) and, indeed, all types of orofacial pains has significantly progressed in the last decade based on international consensus work and operationalized clustering of signs and symptoms. A challenging gap nevertheless continues to exist in terms of understanding the underlying pain mechanisms and link to management. Recently, a novel mechanistic descriptor 'nociplastic pain' was introduced, and diagnostic algorithms and characteristic features were proposed. This narrative and critical review aim to discuss to what extent could painful TMD conditions fit into this category. Moreover, a number of less common types of orofacial pain could possibly also reflect nociplastic pain mechanisms. A model to differentiate TMD pain mechanisms is proposed, and the implications for management are discussed. The purpose of this review is to stimulate original and novel research into mechanisms of orofacial pain and hopefully thereby improve management of the individual patient.

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.

Influence of psychiatric symptom profiles of parents on sleep bruxism intensity of their children

OBJECTIVE

The objective of this study was to evaluate the effects of parental anxiety, depression levels and psychiatric symptom profiles of parents on the occurrence of sleep bruxism in children.

MATERIAL & METHODS

This cross-sectional study was carried out with a sample of 94 children aged 6 to 12 years, divided into two groups: with sleep bruxism (bruxism group-BG) and without sleep bruxism (control group-CG). Beck Depression Inventory (BDI), Symptom Checklist (SCL-90-R), Symptom Checklist and Screen for Child Anxiety Related Emotional Disorders-Parent (SCARED-P) scale were used to assess anxiety and depression levels of parents. All questionnaires were filled out by parents of children. Intraoral and extraoral examinations were carried out of children in the clinic and sleep bruxism was determined. All stress conditions were investigated by logistic regression analysis. In the comparison of the qualitative data, chi-square and Fisher exact tests were used.

RESULTS

The data revealed that participants whose mothers had high anxiety and interpersonal sensitivity scores, and participants whose fathers had a medium level of obsessive-compulsive disorder were more likely to have an SB problem (p < 0.05). According to the results of BDI, the fathers' results between the BG and the CG were not statistically significant (p > 0.05). However, the mothers' results between the BG and the CG were statistically significant (p < 0.05) When all subscales of SCARED-P were evaluated, the separation anxiety disorder subscore was statistically significant in the bruxism group.

CONCLUSION

The psychological status of parents is a significant risk factor associated with SB development in school-age children.

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.

The development of the Standardised Tool for the Assessment of Bruxism (STAB): An international road map

This paper summarises the background reasoning and work that led to the selection of the items included in the Standardised Tool for the Assessment of Bruxism (STAB), also introducing the list of items. The instrument is currently being tested for face validity and on-field comprehension. The underlying premise is that the different motor activities included in the bruxism spectrum (e.g. clenching vs. grinding, with or without teeth contact) potentially need to be discriminated from each other, based on their purportedly different aetiology, comorbidities and potential consequences. Focus should be on a valid impression of the activities' frequency, intensity and duration. The methods that can be used for the above purposes can be grouped into strategies that collect information from the patient's history (subject-based), from the clinical assessment performed by an examiner (clinically based) or from the use of instruments to measure certain outcomes (instrumentally based). The three strategies can apply to all aspects of bruxism (i.e. status, comorbid conditions, aetiology and consequences). The STAB will help gathering information on many aspects, factors and conditions that are currently poorly investigated in the field of bruxism. To this purpose, it is divided into two axes. Axis A includes the self-reported information on bruxism status and potential consequences (subject-based report) together with the clinical (examiner report) and instrumental assessment (technology report). Axis B includes the self-reported information (subject-based report) on factors and conditions that may have an etiological or comorbid role for bruxism. This comprehensive multidimensional assessment system will allow building predictive model for clinical and research purposes.

The association of self-reported awake bruxism and sleep bruxism with temporomandibular pain and dysfunction in adult patients with temporomandibular disorders

OBJECTIVE

To investigate the association of the severity of temporomandibular disorders (TMD) pain and dysfunction with the frequency of self-reported awake bruxism (AB), sleep bruxism (SB), and stress in an adult TMD-patient population.

MATERIALS AND METHODS

This cross-sectional study included 237 TMD patients based on the Diagnostic Criteria for TMD. Age, sex, frequency of self-reported AB and SB, and stress were included as independent variables. TMD pain and TMD dysfunction were included as dependent variables in regression analyses. Univariate and multivariable linear regression analyses were used to predict TMD pain and TMD dysfunction in two separate models. Finally, network analysis was performed to investigate the associations between all variables.

RESULTS

In the univariate analyses, TMD pain was significantly associated with self-reported AB-frequent (unstandardized coefficient (B) = 3.196, 95%CI 1.198-5.195, p = 0.002). TMD dysfunction was significantly associated with AB-frequent (B = 2.208, 95%CI 0.177-4.238, p = 0.033) and SB-sometimes (B = 1.698, 95%CI 0.001-3.394, p = 0.050). In the multivariable analyses, TMD pain was significantly associated with TMD dysfunction (B = 0.370, p < 0.001), stress (B=0.102, p < 0.001). TMD dysfunction was significantly associated with TMD pain (B = 0.410, p < 0.001) only. Network analysis showed that TMD pain is a bridge factor between AB, stress, and TMD dysfunction.

CONCLUSIONS

TMD pain is directly associated with AB, stress, and TMD dysfunction, while TMD dysfunction is only associated with TMD pain.

CLINICAL RELEVANCE

Reducing pain may improve pain-related dysfunction, and the management of AB and stress may improve TMD pain and dysfunction, and vice versa.

Study Regarding the Monitoring of Nocturnal Bruxism in Children and Adolescents Using Bruxoff Device

Bruxism is a parafunctional activity represented by the gnashing and clenching of one's teeth. The aim of this study was to determine the utility of screening and monitoring with a Bruxoff device during nocturnal bruxism in 51 children and adolescents (36 with bruxism and 15 without bruxism) by assessing the variations in the intensity and duration of parafunctional activity in each patient. Bruxoff measurements were recorded for at least 60 min for three consecutive nights for each subject. All the parameters recorded using Bruxoff in the control and the study groups showed a statistically significant difference (p < 0.05). The differences found by comparing the values recorded in the male and female study groups are significant for heart rate, the number of masseter muscle contractions during one night, and mixed contractions. The Bruxoff device proved to be important in diagnosing patients with bruxism in our practice.

The continuous adverse impact of COVID-19 on temporomandibular disorders and bruxism: comparison of pre- during- and post-pandemic time periods

INTRODUCTION

Some of the conditions affected by the COVID-19 pandemic were Temporomandibular Disorders (TMD) and bruxism. The present study compares the effect of the pandemic on TMD and bruxism (sleep and awake) in three time periods: before the pandemic (pre-COV), during the pandemic (during-COV) and after the pandemic subsided (post-COVR).

MATERIAL AND METHODS

A total of 587 adult patients (108 in the pre-COV group, 180 in the during-COV group and 252 in the post-COVR group) who arrived for a routine dental treatment between October 2018 and January 2023 were evaluated according to Axis I diagnosis of the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD). Each patient received a DC/TMD Axis I diagnosis as follows: (i) Painful TMD (defined by the presence of at least one of the following - local myalgia, myofascial pain with referral, arthralgia or headache attributed to TMD); (ii) Non painful TMD (defined by the presence of disc displacement with/without reduction, degenerative joint disorders and/or dislocation), (iii) Possible sleep bruxism (SB) and/or (iv) Possible awake bruxism (AB).

STATISTICAL METHODS

Logistic regression analyses were conducted to establish the impact of time and gender on the prospects of painful TMD, non-painful TMD, SB and AB.

RESULTS

The odds of subjects to be diagnosed with painful TMD at the post-COVR era were 3.3 times higher compared to the pre-pandemic time period (pre-COV, 95% C.I. 1.438-7.585). The odds of subjects to be diagnosed with non-painful TMD during-COV were 4 times higher compared to the pre-COV era (95% C.I. 1.332-12.542). The odds of subjects to present possible SB at post-COVR were 2.7 times higher compared to pre-pandemic (pre-COV, 95% C.I. 1.258-5.889, p < 0.05) and the odds to present possible AB after the pandemic subsided (post-COVR) were 3.2 times compared to the pre-pandemic period (95% C.I. 1.496-6.949). The odds of female subjects to be diagnosed with either painful or non-painful TMD were 3.7-4.4 times higher, compared to males.

CONCLUSIONS

Results indicate that with regard to TMD and bruxism the pandemic adverse effects persist also after COVID-19 subsides and the restrictions caused by it are abolished. Apparently, during the pandemic females were affected more seriously by painful and non-painful TMD than males.

Personality, psychosocial and oral behavioural risk factors for temporomandibular disorder symptoms in Asian young adults

BACKGROUND

The relation between personality, psychosocial factors, somatisation, andoral behaviours as risk factors to temporomandibular disorder symptoms have notbeen well established.

OBJECTIVES

This study examined the association of temporomandibular disorder (TMD) symptoms with personality traits, psychological distress, somatisation and oral behaviours. The psychosocial and oral behavioural risk factors for TMD symptoms were also established in Asian young adults.

METHODS

Participants were recruited from a large private University. Based on the quintessential five TMD symptoms (5Ts) of the DC/TMD, the participants were stratified into those with no (NT), painful (PT), dysfunctional (DT) and mixed (MT) TMD symptoms. Personality traits, psychological distress, somatisation and oral behaviours were evaluated with the Big Five Inventory-10 (BFI-10), Depression, Anxiety, Stress Scales-21 (DASS-21), Patient Health Questionnaire-15 (PHQ-15) and Oral Behaviours Checklist (OBC) accordingly. Data were examined using Kruskal-Wallis/Mann-Whitney U and Chi-squared tests, as well as multivariate logistic regression analysis (α = .05).

RESULTS

Of the 420 young adults (mean age 22.7 ± 1.1 years) evaluated, 41.4% had no TMD symptoms, while 17.4%, 20.0% and 21.2% reported PT, DT and MT, respectively. Though personality traits did not vary notably, participants with MT and PT had significantly higher levels of negative affectivity, anxiety and stress than the NT group. Moreover, those with MT and PT presented significantly greater somatisation and more oral behaviours than the DT and NT groups. Multivariate regression analyses indicated that anxiety, somatisation, sleep-related and waking-state nonfunctional oral activities were associated with painful and/or dysfunctional TMD symptoms.

CONCLUSIONS

Except for sleep-related oral activity, psychosocial and oral behavioural risk factors differed for painful, dysfunctional and mixed TMD symptoms in Asian young adults.

Oral behaviors in young adults: a multidimensional evaluation of the influence of personality, coping, and distress

OBJECTIVES

This study explored the relationship of oral parafunction to the psychological variables of personality, coping, and distress. Correlates of sleeping/waking-state oral activities with the different psychological factors were also examined, along with psychological predictors for high parafunction.

MATERIALS AND METHODS

Young adults from a large private university were enrolled. The frequency of oral behaviors was appraised with the oral behavior checklist (OBC), and participants were stratified into low and high parafunction (LP/HP) groups following the DC/TMD. Personality traits, coping styles, and psychological distress were assessed with the Big Five Personality Inventory-10 (BFI-10), brief-COPE Inventory (BCI), and Depression, Anxiety, Stress Scales-21 (DASS-21) correspondingly. Statistical evaluations were performed using the chi-square/Mann-Whitney U tests, Spearman's correlation, and logistic regression analyses (α = 0.05).

RESULTS

Among the 507 participants (mean age 22.2 ± 1.5 years), 84.6% and 15.4% had low and high parafunction respectively. While personality profiles did not vary substantially, the HP group exhibited significantly greater emotion-focused/dysfunctional coping, general distress, depression, anxiety, and stress scores than the LP group. Associations between OBC and the various psychological variables were weak when significant or insignificant. Neuroticism and dysfunctional coping were moderately correlated to general distress, depression, anxiety, and stress (rs = 0.44-0.60/0.45-0.51). Multivariate analyses indicated that high parafunction was predicted by dysfunctional coping style (OR = 2.55) and anxiety (OR = 1.33).

CONCLUSIONS

Dysfunctional coping was the main risk factor for high parafunction, increasing its odds by about 2.5 times.

CLINICAL RELEVANCE

Oral parafunction appears to be a dysfunctional coping response to psychological distress.

Psychosocial factors associated with pain outcomes in patients with painful temporomandibular disorders and headaches

The objective of this study was to assess the association between psychosocial factors (in terms of anxiety, somatization, depression, and optimism) and pain (in terms of headache pain intensity and pain-related disability), in patients with a painful temporomandibular disorder (TMD) and one of the following headache types: migraine, tension-type headache (TTH), or headache attributed to TMD, corrected for the influence of bruxism. A retrospective study was conducted at an orofacial pain and dysfunction (OPD) clinic. Inclusion criteria were painful TMD, with migraine, TTH, and/or headache attributed to TMD. Linear regressions were performed to assess the influence of psychosocial variables on pain intensity and on pain-related disability, stratified per headache type. The regression models were corrected for bruxism and the presence of multiple headache types. A total of 323 patients (61% female; mean age 42.9, SD 14.4 years) were included. Headache pain intensity only had significant associations in TMD-pain patients with headache attributed to TMD, and anxiety showed the strongest relation (β = 0.353) with pain intensity. Pain-related disability was most strongly associated with depression in TMD-pain patients with TTH (β = 0.444), and with somatization in patients with headache attributed to TMD (β = 0.399). In conclusion, the influence of psychosocial factors on headache pain intensity and pain-related disability depends on the headache type presenting.

The effect of sleep hygiene and physiotherapy on bruxism, sleep, and oral habits in children with sleep bruxism during the COVID-19 pandemic

BACKGROUND

Sleep bruxism has been associated with temporomandibular dysfunction, pain, fatigue, and poor sleep quality.

OBJECTIVE

The aim of this study was to determine the gender and age distribution of sleep and oral habits of children with sleep bruxism and to examine the effect of a sleep hygiene and physiotherapy program.

METHODS

In this cross-sectional study, 82 children aged 6-13 years with sleep bruxism were initially screened between March 2020 and June 2021, from which 37 of them voluntarily attended an 8-week sleep hygiene and physiotherapy program. Evaluations were made using a Visual Analogue Scale (VAS), the Children's Sleep Habits Questionnaire (CSHQ), and the Oral Habits Questionnaire (OHQ) at the beginning and at the end of the 8-week program.

RESULTS

Statistically significant differences were determined between the 6-9 years and 10-13-year age groups in respect of the sleep habits subcategories of resistance to bedtime (p= 0.001), sleep anxiety (p= 0.043), parasomnia (p= 0.040), and sleep respiratory disorder (p= 0.041). Following the 8-week treatment program, a significant reduction was obtained in the VAS value (p< 0.05), CSHQ subcategories of resistance to bedtime (p= 0.001), sleep duration (p= 0.008), parasomnia (p= 0.000), and in the OHQ score (p= 0.000).

CONCLUSION

There was no relationship between sleep bruxism and gender, but a relationship was found with age. The rate of bruxism was seen to decrease with an increase in age. It was determined that oral, sleep habits, and bruxism are closely related, and the rates at which bruxism is seen are affected by the oral habits. Sleep hygiene and physiotherapy have been effective in children with sleep bruxism.

ACTN3 genotype influences masseter muscle characteristics and self-reported bruxism

OBJECTIVES

Main aim of the study was to explore the association between genetic polymorphisms in ACTN3 and bruxism. Secondary objectives included masseter muscle phenotypes assessment between bruxers and non-bruxers and according to genetic polymorphisms in ACTN3.

MATERIALS AND METHODS

Fifty-four patients undergoing orthognathic surgery for correction of their malocclusion were enrolled. Self-reported bruxism and temporomandibular disorders status were preoperatively recorded. Saliva samples were used for ACTN3 genotyping. Masseter muscle samples were collected bilaterally at the time of orthognathic surgery to explore the muscle fiber characteristics.

RESULTS

There were significant differences in genotypes for rs1815739 (R577X nonsense) (p = 0.001), rs1671064 (Q523R missense) (p = 0.005), and rs678397 (intronic variant) (p = 0.001) between bruxers and non-bruxers. Patients with self-reported bruxism presented a larger mean fiber area for types IIA (p = 0.035). The mean fiber areas in individuals with the wild-type CC genotype for rs1815739 (R577X) were significantly larger for type IIA fibers (1394.33 μm² [572.77 μm² ]) than in those with the TC and TT genotypes (832.61 μm² [602.43 μm² ] and 526.58 μm² [432.21 μm² ] [p = 0.014]). Similar results for Q523R missense and intronic variants.

CONCLUSIONS

ACTN3 genotypes influence self-reported bruxism in patients with dentofacial deformity through specific masseter muscle fiber characteristics.

Effect of standardized training in combination with masseter sensitization on corticomotor excitability in bruxer and control individuals: a proof of concept study

Recently, it has been proposed that bruxism could represent an overlearned behavior due to the absence of corticomotor plasticity following a relevant tooth-clenching task (TCT). This study assessed the modulatory effects of a nerve growth factor (NGF) injection on masseter muscle corticomotor excitability, jaw motor performance, pain, and limitation in bruxer and control participants following a TCT. Participants characterized as definitive bruxers or controls were randomly assigned to have injected into the right masseter muscle either NGF or isotonic saline (IS), resulting in a study with 4 arms: IS_Control (n = 7), IS_Bruxer (n = 7); NGF_Control (n = 6), and NGF_Bruxer (n = 8). The primary outcome was the masseter motor evoked potential (MEP) amplitude measured at baseline and after a TCT. After the interventions, significantly higher and lower MEP amplitude and corticomotor map area were observed, respectively, in the IS_Control and NGF_Control groups (P < 0.05). Precision and accuracy depended on the series and target force level with significant between-group differences (P < 0.01). NGF-induced masseter muscle sensitization, in combination with a training-induced effect, can significantly impact the corticomotor excitability of the masseter muscle in control participants indicating substantial changes in corticomotor excitability, which are not observed in bruxers. These preliminary findings may have therapeuthic implications for the potential to "detrain" and manage bruxism, but further studies with larger sample sizes will be needed to test this new concept.

Current Knowledge and Future Perspectives on Awake Bruxism Assessment: Expert Consensus Recommendations

Awake bruxism (AB) is differentiated from sleep bruxism (SB) by the differences in etiology, comorbidities, and consequences related to the different spectrum of muscle activities exerted in relation to the different circadian manifestations. Furthermore, less literature data are available on AB than on SB. The introduction of ecological momentary assessment (EMA) strategies has allowed for collecting valuable data on the frequency of the different activities reported by an individual in his/her natural environment. This strategy has been further improved with the recent use of smartphone technologies. Recent studies have described an average frequency of AB behaviors, within the range of 23–40% for otherwise healthy young adults. An association between AB and some psychological traits has emerged, and the findings have indicated that patients with musculoskeletal symptoms (e.g., temporomandibular joint and/or muscle pain, muscle stiffness, and fatigue) report higher AB frequencies. Preliminary data suggest that muscle bracing and teeth contact are the most commonly reported behaviors, while teeth clenching is much less frequently reported than commonly believed previously. Report of teeth grinding during wakefulness is almost absent. This paper has critically reviewed the currently available approaches for the assessment of AB. In addition, some future perspectives and suggestions for further research have been provided.

Painful Temporomandibular Disorders, Bruxism and Oral Parafunctions before and during the COVID-19 Pandemic Era: A Sex Comparison among Dental Patients

Aim: To evaluate the effect of the current coronavirus pandemic on the prevalence of bruxism, oral parafunctions and painful Temporo-Mandibular Disorders (TMDs) and to evaluate the influence of the pandemic on both sexes. Methods: This retrospective study included 288 dental patients who underwent complete anamnesis and examination according to the Diagnostic Criteria for TMD. The study evaluated two patient populations according to the date of examination: (a) pre-COVID-19 pandemic era (108 patients); (b) COVID 19 pandemic era, where 180 patients were examined during the pandemic. Results: A significant increase in parafunction activity was found in both men and women (p < 0.001) during the COVID-19 pandemic. Awake bruxism (AB) and sleep bruxism (SB) was more prevalent during the COVID-19 pandemic solely in women (AB-p < 0.001; SB-p = 0.014). Conclusions: Men and women were affected by the ongoing stress due to the COVID-19 pandemic, yet women showed a higher influence as compared to men. The long-term exposure to elevated levels of anxiety and stress may aggravate or trigger stomatognathic detrimental conditions. Dentists should be aware and regularly monitor their patients regarding the possible existence and consequences of bruxism and TMD.

Polymorphisms in the HTR2A and HTR3A Genes Contribute to Pain in TMD Myalgia

Background: The aim of this study was to investigate if single nucleotide polymorphisms (SNPs) related to monoaminergic neurotransmission, in particular the serotonergic pathway, contribute to pain perception in patients with temporomandibular disorder (TMD) myalgia and if there is a correlation to jaw function as well as psychosocial factors such as stress, anxiety and depression.

Materials and Methods: One hundred and seventeen individuals with TMD myalgia were included. A venous blood or saliva sample was taken for genetic analyses and genotyped regarding HTR2A (rs9316233) HTR3A (rs1062613), HTR3B (rs1176744), SERT (5-HTTLPR) and COMT (rs4680). A clinical examination according to Diagnostic Criteria for TMD (DC/TMD) was performed and axis II data (psychosocial factors) were compared between participants with different genotypes for each gene using Kruskall–Wallis test. The characteristic pain intensity (CPI) was tested for correlations to scores for the Perceived Stress Scale, Generalized Anxiety Disorder, and Patient Health Questionnaires using Spearman's rank correlation test with Bonferroni correction for multiple testing. To further explore data factor analysis was performed to identify latent factors associated to the outcome variables.

Results: Participants carrying at least one copy of the rare allele of the HTR2A (rs9316233) and HTR3A (rs1062613) had higher CPI compared with the participants with the homozygous common genotype (P = 0.042 and P = 0.024, respectively). Correlation analyses showed several significant positive correlations between CPI on one hand, and self-reported psychosocial distress and jaw function on the other hand for several genotypes that mostly were weak to moderate. The factor analysis identified two latent variables. One was positively correlated to the HTR3B gene, jaw function and self-reported parafunctions, and the other was positively correlated to psychological distress and negatively correlated to SERT.

Conclusion: Taken together, the polymorphism rs1062613 in the HTR3A gene contributes to pain intensity in TMD myalgia. This together with positive interactions between pain variables and psychological factors in genotypes strengthens that pain and psychological distress are related. Further research is needed to explore this as well as the influence of gene-to-gene interactions on pain and psychological distress.

Impact of the COVID-19 Pandemic on Stress, Sleep, and Oral Health in University Students

Background: The COVID-19 pandemic, a disease caused by Sars-CoV-2, has become a worldwide stressor, especially as it represents a new viral infection, which spreads quickly and easily, without prior knowledge about vaccination, and absence, to this moment, of a medication that is totally effective against the disease.

Objective: The aim of this observational study was to provide a general evaluation, through a questionnaire applied to students in the health field of the Federal University of Rio de Janeiro, on the psychological impacts and behavioral changes generated by the COVID-19 pandemic on oral health, especially the triggering or exacerbation of bruxism and temporomandibular disorders (TMD).

Methods: In order to verify the impacts of the pandemic on the health of UFRJ healthcare students, a non-randomized survey was performed with 370 students.

Results: It was found that 72% of the students had their sleep routine altered, 65% had greater difficulty in keeping their spirits up, there was a statistically significant increase in emotional stress, headaches, and daytime teeth clenching.

Conclusion: It was possible to conclude that the outbreak of COVID-19 resulted in psychological, physiological and behavioral impacts on students.

Psychosocial and Behavioral Factors in Awake Bruxism-Self-Report versus Ecological Momentary Assessment

The issue of psychosocial factors and concurrent conditions associated with AB is a relatively new approach in the study of Awake Bruxism (AB). In the present study a population of 84 dental students were assessed for probable AB with two modes of AB assessment: Single point self-report (SR) and ecological momentary assessment through a designated smartphone application (BA). The two assessment modes were compared with regard to their ability to phenotype subjects as far as the following psychosocial and behavioral variables are concerned: Gender; depression; somatization; oral behaviors; chronic pain and associated pain symptoms in the head, neck and scapula. Two-way ANOVA showed main effect of SR for the following variables: Chronic Pain Intensity score (F_(1,49) = 6.441, p < 0.02), migraine/headache (F_(1,81) = 7.396, p < 0.01), pain in neck (F_(1,81) = 6.726, p < 0.05), pain in scapula (F_(1,81) = 8.546, p < 0.005) and the oral behaviors of pushing the tongue forcefully against the teeth (F_(1,81) = 5.222, p < 0.05) and inserting the tongue between the upper and lower teeth (F_(1,81) = 5.344, p < 0.03). The effect of SR on the habit of chewing gum was borderline (F_(1,81) = 3.369, p = 0.07). Main effect of BA was found for depression (F_(1,81) = 6.049, p < 0.05), while the effect of BA on somatization was borderline (F_(1,81) = 3.657, p = 0.059). An interaction between SR and BA groups could be observed for the behavior of biting, chewing or playing with the tongue, cheeks or lips (F_(1,81) = 4.117, p < 0.05). The results suggest that a combination of a single-point self-report referring to the past 30 days, and an ecological momentary assessment supplying information about the actual timing of the report, can help us to better assess AB, as well as increase our ability to define the phenotype of subjects with AB as far as psychosocial and behavioral factors are concerned.

[Prevalence of temporomandibular disorders in seniors-Symptom-related analyses in younger and older seniors]

Hintergrund

Kraniomandibuläre Dysfunktionen (CMD) können auch im hohen Alter auftreten. Die Prävalenz von CMD-Symptomen bei Senioren wurde bisher nur wenig untersucht.

Ziel der Arbeit

Ziel dieser Untersuchung war es, die Prävalenz von Symptomen einer CMD bei Senioren nach Befunderhebung mit den Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) zu bestimmen. Dabei sollten die Prävalenzwerte von jüngeren (60 bis 74 Jahren) und älteren (≥ 75 Jahre) Senioren verglichen werden.

Material und Methoden

Im Rahmen der Interdisziplinären Längsschnittstudie des Erwachsenenalters (ILSE) wurden Probanden nach repräsentativen Gesichtspunkten rekrutiert. Während der vierten Nachverfolgungswelle im Zeitraum von 2014 bis 2016 im Bereich des Studienzentrums Leipzig wurden die Probanden auf das Vorliegen von anamnestischen und klinischen CMD-Symptomen untersucht.

Ergebnisse

Anamnestische CMD-Symptome bei Senioren (n = 192) waren v. a. durch Schmerzen im Gesichtsbereich (13,0 %) gekennzeichnet. Das häufigste klinische CMD-Symptom waren Kiefergelenkgeräusche mit einer Prävalenz bis zu 35,5 %. Frauen gaben anamnestisch häufiger Kopfschmerzen/Migräne an. Kiefergelenkgeräusche und eine limitierte Mundöffnung wurden klinisch häufiger bei weiblichen Teilnehmenden beobachtet. Statistisch signifikante Unterschiede zeigten sich bei dem Vergleich von jüngeren und älteren Senioren hinsichtlich der Prävalenz von Kopfschmerzen/Migräne, jedoch nicht bei klinischen Symptomen.

Schlussfolgerung

Anamnestisch werden Gesichtsschmerzen von 13,0 % der Senioren angegeben. Kiefergelenkgeräusche werden bei jedem dritten Älteren klinisch beobachtet. CMD-Symptome scheinen bei jüngeren und älteren Senioren im ähnlichen Maße ausgeprägt zu sein.

Association of psychological distress and widespread pain with sympatoms of temporomandibular disorders and self-reported bruxism in students

Objectives

The aim of this study was to evaluate the association of psychosocial distress and widespread pain with self‐reported symptoms of temporomandibular disorders (TMD) and bruxism, in two cross‐sectional surveys in 2012 and 2016, and whether there are temporal changes in the magnitude of associations.

Materials and methods

The data were gathered from Finnish university students in 2012 and 2016. TMD symptoms were assessed with three validated questions and bruxism with one frequently used question. Psychosocial distress was assessed with the General Health Questionnaire‐12 (GHQ‐12), and widespread pain with questions of pain in the extremities, the neck or upper back, and lower back. The associations of GHQ‐12, widespread pain and background variables with TMD symptoms and bruxism were analyzed with chi‐square tests, t‐test and binary logistic regression models stratified by gender, and adjusted for age‐group, self‐reported general health/wellbeing and presence of widespread pain.

Results

Higher GHQ‐12 score and presence of widespread pain were significantly associated with TMD symptoms in both genders at both time points. The association of higher GHQ‐12 score with sleep bruxism and awake bruxism were inconsistent. In the adjusted model higher GHQ‐12 score and widespread pain were significantly related to TMD pain symptoms in both genders at both time points, and to bruxism in 2012. Between the two time points a greater variability in these associations was seen in men than in women.

Conclusions

Psychological distress and widespread pain are significant determinants in perceived TMD pain and bruxism among students. No significant temporal alterations were observed.

Painful and non-painful symptoms evoked by experimental bracing and thrusting of the mandible in healthy individuals

BACKGROUND

Bruxism may involve bracing and thrusting of the mandible, in addition to clenching or grinding of the teeth. It is unclear how bracing and thrusting may contribute to potential musculoskeletal symptoms associated with bruxism.

OBJECTIVE

To examine the effect of experimental bracing and thrusting of the mandible on the development of musculoskeletal symptoms in healthy volunteers.

METHODS

Thirty healthy volunteers performed six trials of 5 min of repeated bracing and thrusting of the mandible. Bracing involved forcefully maintaining maximum protruded position (5 s with 1 s rest in between), whereas thrusting involved forcefully moving the mandible in a forward direction and back (1 Hz). The participants rated pain, unpleasantness, soreness, fatigue, tension, stiffness, stress and headache on 10-cm visual analogue scales (VAS) before, immediately and 24 h after the tasks. Pain drawings were obtained and maximum voluntary protrusive force (MVPF) was determined before and after the tasks. The outcome parameters for each task were compared between the time points.

RESULTS

There was a significant increase in the VAS scores (2-4/10) of pain, unpleasantness, soreness, fatigue, tension, stiffness and stress immediately following the tasks compared to baseline and 24 h after the tasks (p < .008). Pain was frequently reported in masseter muscles. MVPF values were significantly higher immediately (p < .001) and 24 h after thrusting (p < .001) and bracing (p = .012) tasks compared to the baseline.

CONCLUSIONS

Experimental bracing and thrusting of the mandible evoked transient, mild-to-moderate levels of muscle pain, fatigue, tension and stiffness and increased unpleasantness and stress scores in healthy volunteers.

Signal acquisition and analysis of ambulatory electromyographic recordings for the assessment of sleep bruxism: A scoping review

Background

Ambulatory electromyographic (EMG) devices are increasingly being used in sleep bruxism studies. EMG signal acquisition, analysis and scoring methods vary between studies. This may impact comparability of studies and the assessment of sleep bruxism in patients.

Objectives

(a) To provide an overview of EMG signal acquisition and analysis methods of recordings from limited‐channel ambulatory EMG devices for the assessment of sleep bruxism; and (b) to provide an overview of outcome measures used in sleep bruxism literature utilising such devices.

Method

A scoping review of the literature was performed. Online databases PubMed and Semantics Scholar were searched for studies published in English until 7 October 2020. Data on five categories were extracted: recording hardware, recording logistics, signal acquisition, signal analysis and sleep bruxism outcomes.

Results

Seventy‐eight studies were included, published between 1977 and 2020. Recording hardware was generally well described. Reports of participant instructions in device handling and of dealing with failed recordings were often lacking. Basic elements of signal acquisition, for example amplifications factors, impedance and bandpass settings, and signal analysis, for example rectification, signal processing and additional filtering, were underreported. Extensive variability was found for thresholds used to characterise sleep bruxism events. Sleep bruxism outcomes varied, but typically represented frequency, duration and/or intensity of masticatory muscle activity (MMA).

Conclusion

Adequate and standardised reporting of recording procedures is highly recommended. In future studies utilising ambulatory EMG devices, the focus may need to shift from the concept of scoring sleep bruxism events to that of scoring the whole spectrum of MMA.

Identifying predictive factors for sleep bruxism severity using clinical and polysomnographic parameters: a principal component analysis

STUDY OBJECTIVES

The aim was to identify predictive factors for sleep bruxism (SB) severity among polysomnographic parameters, salivary cortisol levels, temporomandibular disorders, age, and sex.

METHODS

Young adults (19-30 years) were screened for self-/roommate reports of teeth grinding/clenching during sleep associated with clinical signs of tooth wear. Individuals positive for both conditions were administered a polysomnographic exam to provide a definite diagnosis of SB (n = 28). Healthy participants without SB signs/symptoms were also included (n = 15). The Research Diagnostic Criteria for Temporomandibular Disorders was applied to determine functional, muscular, and articular domains of the Temporomandibular Index. Cortisol awakening levels were measured in saliva. Principal component analysis was used to extract the latent components emerging from polysomnographic results, and 2 regression models were adjusted to predict the number and duration of bruxism episodes.

RESULTS

Principal component analysis resulted in 4 components-C1: %N1, total sleep time, sleep efficiency, arousals/microarousals; C2: %N2, %N3; C3: periodic limb movements and apneas; C4: %REM and REM latency. The number of SB episodes/h was predicted by increasing muscular scores and C2 (decrease in %N2 and increase in %N3) (adjusted R² = 45%; P =.001). The total time of SB episodes was predicted by decreased articular and increased functional scores, age, and female sex (adjusted R² = 36%; P = 0.010). Salivary cortisol levels were not associated with SB severity and did not differ between groups.

CONCLUSIONS

The findings showed that SB severity was predicted by muscular and functional scores, female sex, and distinct polysomnographic patterns, contributing to the deeper knowledge of the underlying pathophysiology of SB severity; additionally, the findings can help to formulate health approaches that are specific to the patient and will better assist in treating this condition.

Associations among masticatory muscle activity, physical activity and self-reported oral behaviours in adult women

OBJECTIVES

To examine the relationship between masticatory muscle activity (MMA), self-reported oral behaviours (OBs) and overall physical activity (PA) in adult women.

MATERIALS AND METHODS

MMA and PA were assessed by a wearable electromyography (EMG) device and accelerometer respectively, worn over 2 non-consecutive days by 53 women (mean age 27.5 ± 6.4 years). Following the second recording day, self-reported OBs were assessed. MMA was assessed by the number, amplitude and duration of masseter contraction episodes. Masseter muscle EMG outcome measures were number of contraction episodes per hour (CEs/h) and the relative contraction time (RCT%). PA was assessed by time accumulated in moderate to vigorous physical activity (MVPA) and 10-min bouts of MVPA per hour. Data were analysed using mixed model analysis.

RESULTS

MMA in free-living conditions consisted mostly of low-amplitude (<10% maximum voluntary clenching) and short-duration (<10 s) contraction episodes. Masseter CEs/h were not associated with self-reported levels of OB. Masseter CEs/h were positively associated with time accumulated in MVPA (F = 9.9; p = 0.002) and negatively associated with 10-min bouts of MVPA/h (F = 15.8; p <0.001). RCT% was not significantly associated with either.

CONCLUSIONS

Objectively assessed MMA is not associated with self-reported OB in free-moving adult females. Moderate to vigorous exercise and physical inactivity are accompanied with an increase in the number of masseter muscle contractions and thus possibly tooth clenching activity.

CLINICAL RELEVANCE

OB can be influenced by the type and extent of PA. Subjective assessment of MMA by questionnaire and/or interviews may be invalid.

Temporomandibular disorders in patients with early rheumatoid arthritis and at-risk individuals in the Dutch population: a cross-sectional study

OBJECTIVE

To evaluate the prevalence of temporomandibular disorders (TMD) in patients with early rheumatoid arthritis (ERA) and individuals at-risk of RA.

METHODS

150 participants were recruited in three groups (50 per group): (1) patients with ERA (2010 EULAR criteria) (2) at-risk individuals and (3) healthy controls. All participants were tested for seropositivity of rheumatoid factor and anticitrullinated protein antibodies. A possible TMD diagnosis was determined according to the standardised and validated diagnostic criteria for TMD (DC/TMD) in five categories: myalgia, arthralgia, articular disc displacement, degenerative joint disease and headache attributed to TMD. Results were tested for the prevalence of TMD (all categories combined) and TMD pain (myalgia and/or arthralgia). To investigate a possible role for bruxism, a probable sleep and/or awake bruxism diagnosis was determined based on self-report and several clinical features.

RESULTS

The prevalence of any TMD diagnosis did not differ between the three groups. However, at-risk individuals more often had a TMD-pain diagnosis than healthy controls (p=0.046). No such difference was found between the ERA group and the control group. However, within the ERA group, seronegative patients had a TMD-pain diagnosis more often than seropositive patients (4/12 (33%) vs 3/38 (8%), p=0.048). Participants with a TMD-pain diagnosis were more often diagnosed with probable sleep bruxism than those without a TMD-pain diagnosis.

CONCLUSION

The prevalence of TMD pain is increased in individuals at-risk of RA and seronegative ERA patients, and is associated with bruxism signs and symptoms. These results suggest that health professionals should be alert to TMD pain in these groups.

Effects of physical therapy for temporomandibular disorders on headache pain intensity: A systematic review

BACKGROUND

Physical therapy is regarded an effective treatment for temporomandibular disorders (TMD). Patients with TMD often report concomitant headache. There is, however, no overview of the effect of physical therapy for TMD on concomitant headache complaints.

OBJECTIVES

The aim of this study is to systematically evaluate the literature on the effectiveness of physical therapy on concomitant headache pain intensity in patients with TMD.

DATA SOURCES

PubMed, Cochrane and PEDro were searched.

STUDY ELIGIBILITY CRITERIA

Randomized or controlled clinical trials studying physical therapy interventions were included.

PARTICIPANTS

Patients with TMD and headache.

APPRAISAL

The Cochrane risk of bias tool was used to assess risk of bias.

SYNTHESIS METHODS

Individual and pooled between-group effect sizes were calculated according to the standardized mean difference (SMD) and the quality of the evidence was rated using the GRADE approach.

RESULTS

and manual therapy on both orofacial region and cervical spine. There is a very low level of certainty that TMD-treatment is effective on headache pain intensity, downgraded by high risk of bias, inconsistency and imprecision.

LIMITATIONS

The methodological quality of most included articles was poor, and the interventions included were very different.

CONCLUSIONS

Physical therapy interventions presented small effect on reducing headache pain intensity on subjects with TMD, with low level of certainty. More studies of higher methodological quality are needed so better conclusions could be taken.

Development and internal validation of prediction models for persistence of self-reported orofacial pain in the follow-up of patients with myofascial pain

Objectives

To identify predictors in patient profiles, and to develop, internally validate, and calibrate prediction models for the persistence of self-reported orofacial pain at the 6-month and 12-month follow-up in patients with myofascial pain.

Materials and methods

A cohort of 63 adult patients with moderate to severe chronic myofascial pain was included. Patient and disease characteristics at baseline were recorded as potential predictors. Patients` presence or absence of improvement of orofacial pain at follow-up was considered the outcome. Binary logistic regression analyses were used to develop the models. The performance and clinical values of the models were determined.

Results

Forty-three percent and 30% of the patients had persistence of orofacial pain at 6-month and 12-month follow-up, respectively. Pain elsewhere, depression, parafunctional activities, and mandibular function impairment (MFI) were significantly associated with persistence of the pain at 6-month follow-up, whereas depression, parafunctional activities, and MFI were significantly associated with persistence of the pain at 12-month follow-up. Both of the models showed good calibration and discrimination, with shrunken area under the curve (AUC) values of 0.73 and 0.76, respectively. The clinical added predictive values for ruling in the risk of the persistence were 0.30 and 0.31, respectively, and those for ruling it out were 0.25 and 0.20, respectively.

Conclusions

Potential predictors for prediction of the persistence of self-reported orofacial pain at follow-up were identified. The calibration, discrimination, and clinical values of the models were acceptable.

Clinical relevance

The models may assist clinicians in decision-making regarding the improvement of orofacial pain of individual patients during follow-up in clinical settings.

The association of self-reported awake bruxism with anxiety, depression, pain threshold at pressure, pain vigilance, and quality of life in patients undergoing orthodontic treatment

This study aimed to evaluate whether the presence of awake bruxism was associated with temporomandibular dysfunction symptoms, pain threshold at pressure, pain vigilance, oral health-related quality of life (OHRQoL), and anxiety and depression symptoms in patients undergoing orthodontic treatment.

Correlations between Sleep Bruxism and Temporomandibular Disorders

The aim of this study was to identify correlations between sleep bruxism (SB) and temporomandibular disorders (TMD) as diagnosed by means of the research diagnostic criteria for temporomandibular disorders (RDC/TMD). Sleep bruxism was diagnosed on the basis of I) validated questionnaires, II) clinical symptoms, and III) electromyographic/electrocardiographic data. A total of 110 subjects were included in the study. Fifty-eight patients were identified as bruxers and 52 as nonbruxers. A psychosocial assessment was also performed. An RDC/TMD group-I diagnosis (myofascial pain) was made for 10 out of 58 bruxers, whereas none of the nonbruxers received a diagnosis of this type. No significant differences were found between bruxers and nonbruxers with regard to RDC/TMD group-II (disc displacement) and group-III (arthralgia, arthritis, arthrosis) diagnoses. Somatization was significantly more common among bruxers than nonbruxers. Multivariate logistic regression analysis revealed that somatization was the only factor significantly correlated with the diagnosis of myofascial pain. The results of this study indicate a correlation between myofascial pain, as diagnosed using the RDC/TMD, and somatization. It seems that somatization is a stronger predictor of an RDC/TMD diagnosis of myofascial pain than sleep bruxism is.

Associations between sleep bruxism and (peri-)implant complications: lessons learned from a clinical study

Objective

To report and discuss the lessons learned from the conduct of a clinical study on the associations between sleep bruxism and (peri-)implant complications, the protocol of which has been pre-published.

Materials and methods

A single-center, double-blind, prospective cohort study with a 2 year follow-up was performed in the Academic Centre for Dentistry Amsterdam (ACTA), The Netherlands. Eleven adult participants were included, where an inclusion of 98 was planned. Sleep bruxism was assessed by multiple single-channel electromyographic (EMG) recordings. Main outcomes were biological and technical complications. Results of the study are presented alongside with comments on encountered difficulties.

Results

Insufficient participant recruitment and failed EMG recordings were encountered. The small sample size did not allow answering the study’s main aim, and was mainly attributed to the study’s protocol complexity. EMG recording failures were attributed to insufficient quality of the EMG signal and detachments of the electrode.

Discussion

The lessons learned from the conduct of this study can be used to design successful future clinical studies.

Conclusions

Adequate participant recruitment, effective EMG recordings, and a careful selection of predictor variables are important ingredients for the successful conduct of a longitudinal clinical study on the association between sleep bruxism and (peri-)implant complications.

The Bruxoff Device as a Screening Method for Sleep Bruxism in Dental Practice

Sleep bruxism (SB) is a masticatory muscle activity during sleep and a common phenomenon. Severe SB can have a serious impact on the success of dental treatment. Reliable methods of screening and diagnosing patients with SB are crucial. Therefore, in this study, a Bruxoff device as a potential screening and diagnostic method for sleep bruxism was evaluated. A total of 60 adults participated in this study: 35 patients with symptoms of bruxism (study group) and 25 asymptomatic patients (control group). Data were recorded using Bruxoff. All symptomatic patients participating in the study turned out to be bruxers, while not all asymptomatic patients turned out to be non-bruxers according to the Bruxoff device. Bruxoff is a simple screening device that can be safely used to evaluate masseter muscle activity during sleep. Since the device does not have a built-in microphone and/or video camera and, therefore, cannot record grinding sounds, the objective capabilities of Bruxoff as a single diagnostic device for sleep bruxism are limited.