Comment on "Electromyographic Assessment of Sleep Bruxism in Patients With Periodontitis: A Case-Control Study".

This cross-sectional observational study aimed to identify the predictors of sleep bruxism (SB) in patients with temporomandibular disorder (TMD) and to comprehensively investigate its association with clinical, sleep-related, psychological, and hematological factors. Seventy-nine patients with TMD (69 females and 10 males; mean age 45.46 ± 14.46 years) were divided into two groups based on the presence or absence of SB: TMD_nonbruxer and TMD_bruxer. Descriptive statistics, correlation analyses, and multivariate stepwise logistic regression were conducted; p < 0.05 was considered statistically significant. In Cramer’s V, SB was correlated with several clinical and sleep-related factors, including TMJ noise (r = 0.52), TMD pain (r = 0.48), craniomandibular index (r = 0.32), limited mouth opening (r = 0.29), tinnitus (r = 0.29), an increase in the Pittsburgh sleep quality index (PSQI) global score (r = 0.24), and poor sleep quality, defined as a PSQI global score ≥ 5 (r = 0.19) (all p < 0.05). SB was also associated with psychological distress. Regarding hematological factors, elevated levels of cortisol (r = 0.30), adrenocorticotropic hormone (ACTH) (r = 0.34), and cortisol/ACTH ratio (r = 0.35) were also associated with SB (all p < 0.05). The factors associated with an increased likelihood of SB ranked in terms of the odds ratio (OR) were: craniomandibular index (OR = 18.400, p = 0.006), poor sleep quality with a PSQI global score ≥ 5 (OR = 11.425, p = 0.027), depression (OR = 1.189, p = 0.014), cortisol/ACTH ratio (OR = 1.151, p = 0.007), anxiety (OR = 1.081, p = 0.040), and adrenocorticotropic hormone (OR = 1.073, p = 0.019). Notably, an increase in age was associated with a decreased likelihood of SB (OR = 0.905, p = 0.006), with a cut-off value of 50 years (AUC = 0.259, 95% CI: 0.149–0.368, p = 0.024), indicating a significant decrease in bruxism occurrence in individuals aged ≥ 50 years. Further analysis revealed complex interconnections between SB and its predictors. In conclusion, SB in TMD patients was associated with age < 50 years, various clinical factors, such as TMD pain and TMJ noise, poor sleep quality, psychological deterioration, and elevated cortisol and ACTH levels.

Aims: The aim of this study was to assess the relationship between levels of anxiety symptoms and prevalence of self-report of awake and sleep bruxism in patients with temporomandibular disorders (TMD).Method: One hundred and eighty-one female patients, aged 19–77 years, were consecutively evaluated. The patients were selected from among those who sought treatment at the TMD and Orofacial Pain Outpatient Clinic of the Petrópolis School of Medicine. All patients completed the questionnaire and underwent clinical examination, both components of the RDC/TMD, in addition to answering questions pertaining to the assessment of levels of anxiety symptoms, taken from the Symptom Check List 90 self-report instrument. The subjects were classified according to the presence of self-reported only awake bruxism, only sleep bruxism, both, or none. A logistic regression procedure was performed to evaluate the possible association through odds ratio between anxiety symptoms and self-reported awake or sleep bruxism. The cofactors for each outcome were age, self-reported bruxism during the circadian period other than the one being evaluated, and the use of selective serotonin reuptake inhibitors.Results: It was possible to demonstrate the presence of a positive and statistically significant relationship between anxiety levels and self-reported awake bruxism. This finding was not observed in those subjects who reported sleep bruxism.Conclusions: A positive relationship was found between self-reported awake bruxism and levels of anxiety symptoms, but not between sleep bruxism and anxiety.

Study Objectives : Nocturnal bruxism is associated with gastroesophageal reflux disease (GERD), and GERD is strongly associated with obstructive sleep apnea (OSA). Gender and ethnic differences in the prevalence and clinical presentation of these often overlapping sleep disorders have not been well documented. Our aim was to examine the associations between, and the symptoms associated with, nocturnal GERD and sleep bruxism in patients with OSA, and to examine the influence of gender and ethnicity.Methods : A retrospective chart review was performed of patients diagnosed with OSA at an academic sleep center. The patients completed a sleep questionnaire prior to undergoing polysomnography. Patients with confirmed OSA were evaluated based on gender and ethnicity. Associations were determined between sleep bruxism and nocturnal GERD, and daytime sleepiness, insomnia, restless legs symptoms, and markers of OSA severity in each group.Results : In these patients with OSA, the prevalence of nocturnal GERD (35%) and sleep bruxism (26%) were higher than the general population. Sleep bruxism was more common in Caucasians than in African Americans or Hispanics; there was no gender difference. Nocturnal GERD was similar among all gender and ethnic groups. Bruxism was associated with nocturnal GERD in females, restless legs symptoms in all subjects and in males, sleepiness in African Americans, and insomnia in Hispanics. Nocturnal GERD was associated with sleepiness in males and African Americans, insomnia in females, and restless legs symptoms in females and in Caucasians.Conclusion : Patients with OSA commonly have comorbid sleep bruxism and nocturnal GERD, which may require separate treatment. Providers should be aware of differences in clinical presentation among different ethnic and gender groups.

Background Chronic painful temporomandibular disorders (TMD), awake bruxism and sleep bruxism are often comorbid with post‐traumatic stress disorder (PTSD), but the implications for treatment are unknown. Objective(s) To explore the effects of PTSD treatment on these conditions. We hypothesized that chronic painful TMD, pain intensity, pain interference, awake bruxism and sleep bruxism would decrease after evidence‐based trauma‐focused treatment and that this decrease would be maintained at the 6‐month follow‐up. Methods Individuals referred for PTSD treatment were assessed for chronic painful TMD (temporomandibular disorder pain screener), pain intensity, pain interference (Graded Chronic Pain Scale 2.0), awake bruxism and sleep bruxism (oral behaviours checklist) pre‐, post‐treatment and at the 6‐month follow‐up. Hypotheses were tested using the Friedman test, followed by a post hoc Wilcoxon signed‐rank test. Effect sizes (Cohen's r ) are reported. Barely any pain interference was reported, therefore these outcomes were not analysed. Results In individuals with chronic painful TMD ( n = 98), pain intensity, awake bruxism and sleep bruxism decreased across the three time points. Post hoc tests showed that chronic painful TMD ( r = 0.59), pain intensity ( r = 0.28), awake bruxism ( r = 0.51) and sleep bruxism ( r = 0.35) decreased between pre‐ and post‐treatment. Between pre‐treatment and the 6‐month follow‐up, chronic painful TMD ( r = 0.58), awake bruxism ( r = 0.30) and sleep bruxism ( r = 0.39) decreased as well. Conclusion The results provide preliminary support for a trauma‐sensitive approach for patients with chronic painful TMD and PTSD and suggest that trauma‐focused treatment may be beneficial for chronic painful TMD, awake bruxism and sleep bruxism in patients with PTSD and chronic painful TMD.

Most rhythmic masticatory muscle activities (RMMAs) have been shown to be accompanied with limb movements (LMs) in sleep bruxism (SB) patients during sleep. To compare the relationships between RMMAs and LMs in SB patients and normal subjects. Polysomnographic recordings were performed on eight SB patients and nine normal subjects and the frequencies and durations of RMMAs as well as LMs were determined. Linear regression and correlation analysis were performed to study the relationship between durations of RMMAs and LMs when RMMAs occurred with LMs. Most LMs in SB patients, but not in normal subjects, were accompanied with RMMAs. RMMAs in SB patients were more likely to be isolated, phasic or mixed, while RMMAs in normal subjects were more likely to be tonic. The frequencies of LMs, isolated RMMAs and RMMAs accompanied with LMs in SB patients were significantly higher than those in normal subjects. Furthermore, linear regression and correlation analysis showed that duration of RMMAs was significantly associated with that of LMs when RMMAs occurred with LMs. The duration of RMMAs, when accompanied with LMs, in SB patients was significantly longer than that in normal subjects. Close relationships between LMs and RMMAs exist in SB patients and normal subjects, and SB episodes may be part of cortical arousal responses and the increased cortical activities associated with SB episodes may not just be localised to the central nervous system (CNS) that controls jaw movements but may also include other parts of CNS that controls LMs.

Contingent electrical stimulation inhibits jaw muscle activity during sleep but not pain intensity or masticatory muscle pressure pain threshold in self-reported bruxers: a pilot study

An increasing number of studies have indicated that the central and autonomic nervous systems play roles in the genesis of sleep bruxism (SB). The role of specific neurochemicals in SB has been a subject of interest. In this study, we use proton magnetic resonance spectroscopy (1 H-MRS) to determine whether the levels of γ-aminobutyric acid (GABA) and glutamate (Glu) are different in the brainstem and bilateral cortical masticatory area (CMA) between possible sleep bruxism (SB) patients and controls, and discuss whether the brainstem or cortical networks which may affect the central masticatory pathways are under the genesis of SB. Twelve possible SB patients and twelve age- and gender-matched controls underwent 1 H-MRS using the "MEGA-Point Resolved Spectroscopy Sequence" (MEGA-PRESS) technique in the brainstem and bilateral CMA. Proton magnetic resonance spectroscopy data were processed using LCModel. Because the signal detected by MEGA-PRESS includes contributions from GABA, macromolecules (primarily proteins) and homocarnosine, the GABA signal is referred to as "GABA+". The glutamate complex (Glx) signal contains both glutamate (Glu) and glutamine (Gln), which mainly reflect glutamatergic metabolism. Edited spectra were successfully obtained from the bilateral CMA in all subjects. There were no significant differences in neurochemical levels between the left and right CMA in possible SB patients and controls. In the brainstem, significantly lower GABA+ levels were found in possible SB patients than in controls (P=.011), whereas there was no significant difference (P=.307) in Glx levels between the 2 groups. SB patients may possess abnormalities in the GABAergic system of brainstem networks.

BackgroundBy being aware of the associated factors of primary snoring (PS) and obstructive sleep apnoea (OSA) in sleep bruxism (SB) patients, dentists may contribute to the screening and early recognition of SB patients with PS or OSA.ObjectiveTo identify the associated factors of PS and OSA from questionnaire‐based data in SB patients.MethodsA total of 968 self‐reported SB patients (31.6% men; median age 44.5 years) were retrospectively enrolled. Self‐reported sleep‐related breathing status (viz., no sleep‐related breathing condition, PS and OSA) was the dependent variable. Independent variables were questionnaire‐based data on demographics, lifestyle, psychological status, pain and sleep.ResultsFor PS, no statistically significant associated factor was identified in analyses. For OSA, increased age (OR = 1.04 [1.03–1.06]), male gender (OR = 3.33 [2.17–5.00]), daily alcohol consumption (OR = 1.96 [1.18–3.33]), depression (OR = 1.10 [1.06–1.14]), daytime sleepiness (OR = 2.94 [1.85–4.76]) and high risk of gastroesophageal reflux disease (GERD; OR = 2.63 [1.52–4.76]) were found to be significant risk factors, while high risk of temporomandibular disorder (TMD) pain (OR = 0.51 [0.30–0.86]) and chronic pain (OR = 0.73 [0.59–0.90]) were significant protective factors. These results were confirmed in the subsequent network analysis.ConclusionWithin the limitations of this study, no associated factor is identified for PS. For OSA, dentists should keep in mind that increased age, male gender, daily alcohol consumption, depression, daytime sleepiness and high GERD risk are associated with increased OSA risk in SB patients, while high TMD‐pain risk and chronic pain are associated with decreased OSA risk in this population.

Sleep bruxism in patients with sleep-disordered breathing

Eye movements in relation to rhythmic masticatory muscle activities in patients with sleep bruxism

Relationship between polysomnography findings and sleep bruxism in patients with multiple system atrophy

Review for "The effects of trauma‐focused treatment on painful temporomandibular disorders, awake bruxism and sleep bruxism in patients with severe post‐traumatic stress disorder"

Review for "The effects of trauma‐focused treatment on painful temporomandibular disorders, awake bruxism and sleep bruxism in patients with severe post‐traumatic stress disorder"

Decision letter for "The effects of trauma‐focused treatment on painful temporomandibular disorders, awake bruxism and sleep bruxism in patients with severe post‐traumatic stress disorder"

Objective: Bruxism-induced mechanical load causes various dental problems, and its treatment is challenging. The present study analyzed upper and lower tooth contacts to determine actual occlusal contact during sleep bruxism.Methods: Tooth contact patterns were analyzed in 49 patients attending dental clinics, using a Bruxchecker®, cephalograms, and condylographs.Results: Approximately 80% of individuals demonstrated contact from the anterior teeth to the molar region (ICPM); about 96% had mediotrusive grinding and contact. The tooth contact area increased with the flatness of the anterior occlusal plane. The ratio of the contact area of the anterior teeth to the overall tooth contact area increased with overbite. Bilateral ICPM and mediotrusive contact patterns were associated with a high frequency of temporomandibular disorder symptoms, clicking, and/or pain.Discussion: The tooth contact area, anterior occlusal plane, and overbite are closely related, suggesting that tooth contact with the anterior teeth should be controlled with occlusal therapy.