Bruxism Research Articles

Performance of Bonded Lithium Disilicate Partial-coverage Crowns in the Restoration of Endodontically Treated Posterior Teeth: An Up to Seven-Year Retrospective Study.

To evaluate the clinical performance of adhesively bonded lithium disilicate glass-ceramic (LDG) partial-coverage crowns in restoring posterior endodontically treated teeth (ETT). A total of 121 morphologically compromised posterior ETT were restored with LDG partial-coverage crowns between October 2015 and January 2018. The restorations were fabricated in the laboratory or at the chairside. Two adhesive systems and resin cements were used to cement the restorations. Tooth and restoration survival rates were calculated. The restorations were evaluated clinically using the modified United States Public Health Service (USPHS) criteria for an observation period of 5-7 years. The Cox proportional hazards model was used to estimate relative failure risks such as tooth type, resin cements, gender, and sleep bruxism. The standard chi-squared test was used to compare the survival of different tooth types for significant differences (α=0.05). In addition, survival probability was calculated using the Kaplan-Meier algorithm. Among seven failed cases, one was a tooth fracture, and six were restoration fractures. According to the Kaplan-Meier analysis, the estimated survival rate of the teeth was 99% for seven years, while the estimated survival rate of the restorations was 94.8% for 5 years and 92.8% for 7 years. Tooth type and resin cements did not influence restoration survival rates (p>0.05), while sleep bruxism and male patients might increase the risk of failure (p<0.05). The indirect adhesively bonded LDG partial-coverage crowns of posterior ETT exhibited favorable clinical outcomes. Ceramic fracture was the most common failure pattern.

Genetics and sleep bruxism: a systematic review and meta-analysis of studies with twins.

To systematically review the literature regarding the concordance of sleep bruxism (SB) between monozygotic (MZ) and dizygotic (DZ) twins. The registration for this systematic review was accomplished in the International Prospective Register of Systematic Reviews (PROSPERO, No. CRD42021251751). As of July 2022, four databases were searched, including PubMed, Scopus, Embase, and Web of Science, as well as the grey literature in Google Scholar and OpenGrey. Observational studies evaluating SB in MZ and DZ twins of any age and sex were included. For the evaluation of the risk of bias, the Joanna Briggs checklist was utilized. The certainty of evidence was assessed via the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. Pooled and subgroup meta-analyses were performed to estimate concordance of SB ​​between twins (p < 0.05). In total, 3,155 records were identified. In the qualitative analysis, eleven studies were included; of these, seven were included in the meta-analysis. The majority of the articles exhibited a low risk of bias (63.6%). Greater SB concordance was observed between MZ twins than between DZ twins in the analysis of general concordance (OR = 1.47; 95% CI = 1.07-2.02) and also positive concordance (OR = 1.53; 95% CI = 1.29-1.81). Within the subgroup analyses, the significance of the findings remained only for the reported/self-reported SB regarding general concordance (OR = 1.44; 95% CI = 1.07-1.95) and positive concordance (OR = 1.55; 95% CI = 1.28-1.88). Low certainty of the evidence was observed for the general concordance analysis, while moderate certainty was observed for the positive concordance. There was a higher concordance of SB in MZ twins compared to DZ twins, indicating a possible genetic influence on the condition's occurrence.

SSRI Induced Sleep Bruxism and Jaw Muscle Dystonia- Management with Low Dose Quetiapine Along with Occlusal Guards (D9944, D9945)- Two Case Reports

Background: Long term use of SSRIs (selective serotonin re uptake inhibitors) sometimes induces a problem called nocturnal or sleep bruxism which is nothing but uncoordinated jaw muscle movements which leads to grinding and clenching of teeth. The undesired effect of SSRIs produces a muscle stiffness, jaw and neck muscle tenderness, continuous toothache, hypersensitivity, tooth fracture and TMJ pain. Different treatment modalities are there to manage this kind of problem without hampering the psychiatric prognosis of the patient. Here two cases of SSRI induced sleep bruxism along with successful managements are discussed which will throw some light to the potential treatment approaches of such rare disorders.

Sleep Bruxism and Obstructive Sleep Apnea Are Not Risk Factors for Tension-Type Headache (TTH): A Polysomnographic Study.

Background: Tension-type headache (TTH) is the most common primary headache. Obstructive sleep apnea (OSA) and sleep bruxism (SB) are two of the most common sleep disorders; however, the relationship between TTH, OSA, and SB has not been conclusively proved in the literature. The objective of our study was to estimate potential associations with OSA and SB in TTH subjects. Methods: 108 adult individuals who underwent polysomnography (vPSG) were included, and the group was divided into two subgroups: TTH (n = 34) and control (n = 74). The International Classification of Headache Disorders (ICHD-3) guidelines were used to diagnose TTH. OSA and SB diagnoses were based on vPSG examination with electromyographic (EMG) recordings and the American Academy of Sleep Medicine (AASM) criteria. The results were analyzed, where p < 0.05 was considered to be statistically significant. Results: In the TTH group, the incidence of SB was more than two times lower than the control (OR = 0.41, 95% CI: 0.17-0.96, p < 0.05). However, the incidence of severe SB (BEI > 4) was similar in the TTH and control groups (OR = 0.54, 95% CI: 0.21-1.35, p > 0.05). Additionally, phasic and tonic SB episodes were less frequent in the TTH group compared to the controls (p < 0.05). The mean apnea-hypopnea index (AHI) was not significantly different between the TTH and control groups (p > 0.05). The sleep architecture and respiratory disturbances did not differ between the examined groups (p > 0.05). Conclusions: SB is not a risk factor for TTH. Moreover, severe SB is not connected with TTH. OSA is not a risk factor for TTH. Sleep quality did not differ between both groups during PSG; therefore, TTH may not change sleep structure. The mechanism of these findings is still unclear, and further studies should explain in detail the association between TTH and OSA.

Risk factors for noncarious cervical lesions: A case-control study.

Noncarious cervical lesions (NCCLs) are multifactorial and can be caused by the anatomical structure of the teeth, erosion, abrasion and abnormal occlusion. The aim of this case-control study was to explore the risk factors for NCCLs. Cone-beam computed tomography was used to determine whether a wedge-shaped defect existed at the cementoenamel junction. We compared 63 participants with NCCLs with 63 controls without NCCLs, matched for sex, age (±1 year) and toothbrushing-related factors (e.g., type of bristle and brushing patterns, frequency and strength). All participants were asked to complete a questionnaire about self-administered daily diet habits and health condition. Univariate and multivariate logistic regression analyses were conducted to determine the risk factors for NCCLs. Significant variables in the univariate analysis (i.e., p < .2) included frequency of carbonated beverage consumption, sella-nasion-point B angle (SNB) and Frankfort-mandibular plane angle (FMA). Multivariate logistic regression demonstrated that the consumption frequency of carbonated beverages (odds ratio [OR] = 3.147; 95% confidence interval [CI], 1.039-9.532), FMA (OR = 1.100; 95% CI, 1.004-1.204) and SNB (OR = 0.896; 95% CI, 0.813-0.988) was independent influencing factors. The area under the receiver operating characteristic curve (AUC) value of regression Model 1 (established with the frequency of carbonated beverage consumption, FMA, SNB and sleep bruxism) was 0.700 (95% CI, 0.607-0.792; p < .001), and that of regression Model 2 (established using the frequency of carbonated beverage consumption, FMA and SNB) was 0.704 (95% CI, 0.612-0.796; p < .001). The consumption frequency of carbonated beverages and FMA was risk factors for NCCLs; the higher the frequency of carbonated beverage consumption and FMA, the higher was the probability of NCCLs. SNB was a protective factor for NCCL occurrence; the larger the SNB, the lower was the probability of NCCL occurrence. These findings have further clarified the aetiology of NCCLs and provided clinicians with valuable insights into strategies for preventing the loss of dental tissue.

Dependence of regional circulation in periodontal tissues on the condition of occlusive-articulatory disorders in patients with chronic generalized periodontitis

Abstract Introduction. The scientific substantiation of the causal relationships of traumatic occlusive forces and periodontal diseases is a difficult task and this issue is still debatable. According to available data, occlusive loads in the area of compression of periodontal ligaments lead to changes in blood circulation in lymphatic and blood vessels, which increase the inflammatory process when the adaptive capacity of the periodontal is exceeded. It is necessary to obtain additional information to choose tactics for reducing premature contacts in chronic generalized periodontitis. The aim of the study was to study the state of regional blood circulation in periodontal diseases with the elimination of occlusive obstacles by selective grinding of teeth. Results and discussion. 25 patients with occlusal interference before and after grinding were examined. In the study group, a decrease in the rheographic index by 41% and an increase in the time of rapid and slow blood filling by 1.5 and 1.6 times, respectively, before occlusive grinding were found. After the elimination of premature supracontacts, hemodynamic parameters changed in the opposite direction, the rheographic index increased, and the α1 and α2 indicators decreased. Other hemodynamic criteria studied approached the values in the comparison group. Conclusion. The results of the study confirm the expediency of minimally invasive interventions to eliminate occlusive interference in order to improve hemodynamics in periodontal tissues.

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

AbstractBackgroundChronic 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.MethodsIndividuals 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.ResultsIn 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.ConclusionThe 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.

Phenotyping of somatosensory tinnitus and its associations: An observational cross-sectional study.

Somatosensory tinnitus (ST) is associated with activation of the auditory pathway by trigeminal or cervical afferents. This is a cross-sectional observational study that aims to verify the association of ST with TMD, bruxism, migraine and psychosocial aspects. This study was conducted at the Tinnitus Outpatient Clinic of the Clinical Hospital Complex of the Federal University of Paraná. Specific ST characteristics, were evaluated according to the last consensus for the diagnosis of ST. Two groups with 39 individuals each one were formed, the ST group (STG) and the comparison group (CG). TMD was classified according to the Diagnostic Criteria for Temporomandibular Disorders and migraine by the International Classification of Headaches. The presence of probable sleep and awake bruxism was associated with individual's reports and clinical inspections. The applied questionnaires investigated oral behaviours (OB), sleep quality (SQ), psychosocial aspects (PA), central sensitization (CS), tinnitus impact on quality of life (TIQF), and graded chronic pain scale (GCPS). The STG showed a significant association with modulation manoeuvres and trigger points; myalgias and arthralgia; disc displacement with and without reduction; subluxation; bruxism; and presence of migraine. For the same group, we found a significant association with OB, PA, CS, TIQF and GCPS. There was no significant difference between groups regarding SQ. There is a significant association between the presence of ST and the occurrence of TMD, probable sleep and awake bruxism, and migraine. There is also a greater impairment of OB, PA, CS and TIQF.

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

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.

Effects of different tooth grinding procedures on the occurrence of tooth injuries, skin lesions, performance and behaviour of suckling piglets

BackgroundImmediately after birth, newborn piglets fight to establish a teat order. During this process, lesions appear on the piglets’ faces and on the sows’ teats, which is why tooth resection is carried out on many farms in Germany even though it is known that this procedure is frequently resulting in pulp openings. The opening of a pulp cave is suspected to cause painful tooth alterations and may be an entrance for infectious agents. The purpose of this study was to analyse the effect of tooth resection on skin lesions, development of bodyweight and behaviour in suckling piglets. Four days prepartum, 110 sows in farrow-to-finish production were assigned to one of three treatments. Litters had their teeth left intact (control group, CG), ground with a tea-cup roller head (Tea-cup head grinder group, TCG, Wilofa Diamant, D-56,133 Fachbach, Germany) or ground with a diamond rolling head (rolling head grinder group, RG, IBS/E Company Proxxon GmbH, 54,343 Föhren, Germany). The number of pulp openings in the RG and TCG was examined using a random sample. Piglet body weight and skin lesion scores were recorded within the first 24 h after birth and during each week of the suckling period. Each sow’s udder was examined before farrowing, in the second week of lactation and at weaning. The behaviour of the litters from nine sows was video-recorded throughout the suckling period. The aim of this study was to investigate the effects of tooth grinding by a tea-cup head (compared to grinding by a diamond roller head and no grinding [control group]) on the behaviour and average daily gain of piglets as well as on skin lesions on sow udder.ResultsThe number of dental injuries was significantly greater in the RG than in the TCG (p < 0.01). Head lesions on piglets were significantly more common in the CG than in the RG (p = 0. 02). Compared to CG piglets, TCG piglets had a significantly greater weight at the end of the suckling period (p = 0.02). No significant difference between treatments was found in the sows’ udder (parenchyma, skin, or teat) or in the behaviour of the litters.ConclusionAs tooth grinding is frequently inducing pulp openings, the necessity of the procedure should be carefully and critically scrutinised. In case tooth resection seems inevitable until the underlying management problems have been solved, the Tea-cup grinding head should be used due to significantly fewer pulp openings.

Awake bruxism behaviors frequency in a group of healthy young adults with different psychological scores

ABSTRACT Objective To assess the frequency of awake bruxism (AB) behaviors in a group of undergraduate dentistry students and correlate it with the status of anxiety and depression. Materials and Methods The frequency of five oral behaviors (i.e., relaxed jaw muscle, teeth contact, mandible bracing, teeth clenching, teeth grinding) was evaluated using a smartphone-based ecological momentary assessment (EMA) approach. The anxiety and depression status was investigated with the four-item patient health questionnaire for anxiety and depression (PHQ-4). ANOVA with Tukey post-hoc test was used to assess the difference in frequency of AB behaviors among the four PHQ-4 groups. Results Among the four groups, there was a statistically significant difference in the frequency of relaxed jaw muscle, teeth contact, mandible bracing, and teeth clenching, but not for teeth grinding. Conclusion Based on this cross-sectional study’s findings, psyche seems to have a determinant impact on AB behaviors, which is significantly higher in individuals with anxiety and depression traits.

Reduction of sleep bruxism events according to contingent electrical stimulus intensity.

Although biofeedback with contingent electrical stimulation (CES) has demonstrated the reduction effect on sleep bruxism (SB), the relationship between the actual applied CES intensity and efficacy remains uncertain. This study aimed to investigate whether the reduction of bruxism events and jaw muscle symptoms could vary according to the intensity of CES and in probable sleep bruxers. Twenty probable sleep bruxers were initially screened for bruxer confirmation based on a 2-week recording of SB events with a portable electromyography recorder (BUTLER®GrindCare®, GC4). A 3-week recording was conducted without CES using a GC4, followed by another 3-week recording with CES. At baseline and before and after the CES (+) session, clinical muscle symptoms were assessed using a 0-10 numerical rating scale (NRS). The relationships between the actual applied CES intensity and the number of SB events/hour, as well as the NRS of clinical muscle symptoms, were analysed. The actual applied CES intensity was positively correlated with the reduction rate of the number of SB events/hour (R = .643, p = .002), as well as with the reduction rate of NRS for pain, unpleasantness, fatigue, tension and stiffness (R > .500, p < .011). Higher CES elicited a more robust reduction in SB events and clinical muscle symptoms, in probable bruxers. Prior to selecting CES biofeedback as a management option for SB, it would be beneficial to assess the tolerance threshold of CES in each bruxer in order to predict the effectiveness of CES in probable sleep bruxers.

Qualitative suggestions for the further development of the Standardized Tool for the Assessment of Bruxism (STAB).

The Standardized Tool for the Assessment of Bruxism (STAB) has recently been published. It contains Axis A for evaluating bruxism status and its potential consequences, and Axis B for bruxism risk, etiological factors and comorbid conditions. Suggestions from daily clinical practice can contribute to the further development of the STAB. The study aimed to investigate the experiences and attitudes of general dentists, dentists specialized in Orofacial Pain and Dysfunction (OPD) and Disability Care (DC) regarding the assessment and etiology of sleep and awake bruxism and to examine the concordance of their experiences and attitudes with the respective STAB axes and its domains. Semi-structured interviews were conducted with 11 dentists. The main themes included bruxism assessment and etiology. Thematic analysis identified subthemes. The concordance between main themes, subthemes, and the corresponding STAB axes and domains was examined. Overall, there was a good correspondence between the experiences and attitudes of the interviewees and the respective STAB axes and domains. Some discrepancies were identified, but they were mainly related to the lack of appropriate tools for the DC setting. It is suggested that future versions of the STAB include appropriate tools for the assessment of bruxism in DC settings.

Sleep Bruxism and Sleep Structure in Comorbid Insomnia and Obstructive Sleep Apnea (COMISA) Syndrome: A Polysomnographic Study.

Introduction: Comorbid insomnia and obstructive sleep apnea (COMISA) is not a well-identified sleep disorder, despite having a significant impact on health. This study investigates the relationship between sleep bruxism (SB) and sleep architecture in patients with COMISA, obstructive sleep apnea (OSA), and in those without any sleep disorders. Methods: 119 patients were included in the study and divided into three groups: OSA, COMISA, and a control group. Polysomnographic (PSG) examination provided parameters related to sleep architecture, OSA, and characteristics of SB. Results: The bruxism episode index (BEI) and other SB parameters were not found to be statistically different between the three groups (p > 0.05). There was no statistical difference in measured sleep architecture between the COMISA and OSA groups (p > 0.05). In comparison to the control group, participants in the COMISA group were found to have an increased apnea-hypopnea index (AHI), oxygen desaturation index (ODI), respiratory disturbance index (RDI), all arousals (AA), and respiratory arousals (RA) (p < 0.05). Among COMISA patients, AA and RA were shown to have a positive linear correlation with the number of bradycardia events per hour (r = 0.49, r = 0.48, p < 0.05). Conclusions: SB does not occur in patients with COMISA more frequently than in patients with OSA or those without any sleep disorders. PSG parameters are not specific for COMISA; therefore, in order to differentiate this disorder from OSA alone, a comprehensive patient assessment has to be performed.

Effects of the low Fowler's sleep position and methazolamide treatment on sleep bruxism: A randomized controlled trial.

Intracranial pressure is one of the determinants of sympathetic activities, and sleep bruxism is associated with increased sympathetic activities. This study aimed to investigate effects of the low Fowler's sleep position and methazolamide treatment on the occurrence of rhythmic masticatory muscle activities/sleep bruxism episodes in patients with sleep bruxism in a randomized controlled trial. Polysomnographic recordings were performed on the patients with sleep bruxism sleeping in the low Fowler's (15°-30°) or supine position (n = 11), and with methazolamide or placebo treatment (100 mg, 3-4 hr before bedtime, P.O., n = 9), and changes in sleep variables and heart rate variance during sleep in the low Fowler's position or with methazolamide treatment were determined. Sleep bruxism index, number of masseter muscle electromyographic bursts per hour of sleep, ratio of rhythmic masticatory muscle activities/sleep bruxism duration to the total sleep duration, index of total limb movements, index of limb movements with rhythmic masticatory muscle activities, and number of sleep bruxism clusters per hour of sleep in the low Fowler's position and after methazolamide intake were significantly smaller (p < 0.05-0.001) than those in the supine position and after placebo intake, respectively. The low-frequency heart rate variance powers during non-rapid eye movement sleep stage 2 (N2) in the low Fowler's position and with methazolamide treatment were significantly lower (p < 0.05) than those during sleep in the supine position and with placebo treatment, respectively. In conclusion, sleep in the low Fowler's position and methazolamide treatment were associated with significant decreases in the occurrence of rhythmic masticatory muscle activities/sleep bruxism episodes, which might be due to a reduction in intracranial pressure and sympathetic activities mainly during non-rapid eye movement sleep stage 2.

Intraoral Scanning for Monitoring Dental Wear and Its Risk Factors: A Prospective Study.

Dental wear arises from mechanical (attrition or abrasion) and chemical (erosion) factors. Despite its prevalence and clinical significance, accurately measuring and understanding its causes remain challenging in everyday practice. This one-year study with 39 participants involved comprehensive examinations and full-arch intraoral scans at the start and after 12 months. Volume loss exceeding 100 µ on each tooth's surfaces (buccal, lingual/palatine and incisal/occlusal) was measured by comparing three-dimensional scans from both time points. This study also assessed factors such as abrasion and erosion through clinical exams and questionnaires. There were no significant differences in dental wear in participants with sleep bruxism. However, noticeable wear occurred in the front teeth of those with waking bruxism and joint-related symptoms. Increased wear was associated with frequent consumption of acidic drinks, regular swimming, dry mouth, nocturnal drooling and heartburn, while no significant wear was found in patients with reflux. The used methodology proved effective in accurately assessing the progression of dental wear, which is important as many patients may initially be asymptomatic. The variability observed in dental wear patterns underscores the need to develop specific software applications that allow immediate and efficient comparison of wear areas based on extensive analysis of patient databases.

Efficacy and Safety of Botulinum Toxin in the Management of Temporomandibular Symptoms Associated with Sleep Bruxism: A Systematic Review.

Sleep bruxism, characterized by involuntary grinding or clenching of teeth during sleep, poses significant challenges in management due to its potential to induce temporomandibular joint disorders (TMDs) and other related symptoms. The use of Botulinum toxin Type A (BoNT-A), also known as Botox®, has been proposed as a therapeutic intervention. This systematic review aims to evaluate the efficacy and safety of BoNT-A in the management of sleep bruxism, focusing on pain reduction, improvement in jaw function, reduction in bruxism episodes, and the incidence of adverse effects. An exhaustive search was conducted across PubMed, Scopus, and Embase databases up to January 2024, adhering to the PRISMA guidelines. Nine randomized clinical trials (RCTs) involving 137 participants were analyzed for efficacy and safety outcomes. The studies demonstrated a significant reduction in mean pain scores (from 7.1 to 0.2 at 6 months and 1 year post-treatment in one study) and a notable decrease in the number of bruxism events (from 4.97/h to 1.70/h in the BoNT-A group in another study). Additionally, improvements were observed in jaw stiffness and total sleep time. Adverse effects varied but were generally mild and transient, including injection site pain in 20% of participants in one study and cosmetic changes in smile in 15.4% of patients in another. These findings suggest that BoNT-A injections may provide some benefits for treating nocturnal bruxism, potentially reducing TMD symptoms like pain and improving jaw function. However, these findings are preliminary due to variability in study designs and the absence of detailed statistical analysis.

Why am I grinding and clenching? Exploration of personality traits, coping strategies, oral parafunctional behaviors, and severe sleep bruxism in a polysomnographic study.

Causal relationships between psychopathological symptoms, personality traits, coping mechanisms, and sleep bruxism (SB) were studied in the past, giving inconsistent results mostly based on self-assessment evaluations. This polysomnography-based cross-sectional study aimed to explore the relationships between severe SB, personality traits (according to the Big Five model), and coping strategies with objective polysomnographic verification. The study included 66 participants divided into severe SB (SSB) (n=32) and no or mild SB (n=34) groups based on video-polysomnography performed in the sleep laboratory. Questionnaire assessment included the use of the Beck Depression Inventory, Beck Anxiety Inventory, Mini-COPE, International Personality Item Pool Big Five Markers 20-Item version, and Oral Behavior Checklist. Participants with SSB presented with fewer self-reported anxiety (p=0.008) and depressive (p=0.01) symptoms than the non- or mild-SB groups. The SSB group scored significantly higher in Big Five personal traits such as extraversion (p=0.007), emotional stability (p=0.013), and intellect (p=0.004), while regarding coping strategies, the SSB group was less likely to use negative strategies: self-distraction (p=0.036), denial (p=0.006), venting (p=0.03), behavioral disengagement (p=0.046), and self-blame (p=0.003), and turning to religion (p=0.041). The intensity of oral parafunctional behaviors was comparable in both groups (p=0.054). Emotional stability was a moderate protective factor (p=0.004), and the self-blame strategy was a strong risk factor (p<0.001) for increased oral parafunctional behavior intensity. Phasic activity negatively correlated with anxiety symptom severity (p=0.005), whereas tonic (p=0.122) and mixed (p=0.053) phenotypes did not. SB intensity was a protective factor against anxiety symptoms (p=0.016). In terms of psychopathology, severe sleep bruxers tend to present less severe anxiety and depressive symptoms, while some of their personality traits (extraversion, emotional stability, and intellect) were more strongly pronounced. SSB is possibly related to the lesser use of the "maladaptive" coping strategies and there were no specific coping strategies preferred by SSB participants, compared to the other group. These observations require further studies, as it should be determined whether SB (especially phasic activity) might be a form of a somatization/functional disorder. Further research should focus on the psychogenic background of oral parafunctional behaviors, which occur more often in less emotionally stable personalities and in people using self-blame coping strategies.

Sleep hygiene measures combined with mindfulness meditation in the management of sleep bruxism in children: A randomized controlled clinical trial.

Sleep hygiene measures and meditation may reduce stress and improve sleep quality, but their effect on the occurrence of sleep bruxism in children has not yet been investigated. To explore the effects of sleep hygiene measures combined with mindfulness meditation (relaxation audio) in the management of probable sleep bruxism (SB) in children. This clinical trial (no. NCT04501237) randomized 36 children with 3-8 years of age. Probable SB detection was performed according to the criteria established by the International Consensus on The Assessment of Bruxism-2018. Intervention group was instructed to practice sleep hygiene measures and mindfulness meditation (i.e., the use of a digital app to broadcast audio relaxation) each night before bedtime for 5 weeks; control group did not receive guidance for therapies. Parents completed a bruxism diary for 5 weeks, and the outcome was the number of SB episodes-day reported in the week (ranging from 0 to 7) in each period. A multilevel mixed-effects Poisson regression model was performed. A total of 32 children (mean age: 6.1 years) completed the study. The children who received the therapies related to sleep hygiene measures and mindfulness meditation had a reduction in the SB incidence rate ratio (IRR)of 46% (IRR = 0.54 [Confidence Interval 95%, 0.45-0.65]) during a 5-week observation period. The sensitivity analyses did not show relevant changes in the measure of the effect. Sleep hygiene measures combined with mindfulness meditation reduced the SB in children.

APPLICATION OF BOTULINUM TOXIN IN CONSERVATIVE TREATMENT OF MASTICATORY MUSCLES DYSFUNCTION

The purpose of this paper is to describe the application of the botulinum toxin in diseases of the temporomandibular system of a muscular type such as masticatory hypertrophy, spasm, bruxism, and tension headaches of idiopathic etiology. The masticatory system is a complex apparatus with great adaptive capacity. Still, when that capacity is exceeded, functional disorders occur followed by a series of symptoms that depend on individual, local, and systemic etiological factors. Occlusal trauma exceeding the physiological limits of the teeth, periodontium, and TMJ leads to a series of functional disorders. Temporomandibular dysfunctions (TMD) are used to describe a large, heterogeneous group of diseases of the temporomandibular joint (TMJ) and its adjacent tissues and organs. Botulinum toxin type A, hemagglutinin complex with 500 IU (DISPORT Ipsen Biopharm, UK) was used for the therapy of muscle disorders like bruxism or night teeth clenching in female patient 26 years old. Depending on the dose that was applied to the targeted muscle, a complete or partial reduction in contraction occurs with reduced function and weakening of the muscle. Two weeks after applying the neuromodulator, the patient reported a reduction in pain and episodes of teeth grinding and clenching. Bilateral hypotrophy of left and right masseter muscles was noticeable after 2 months. We concluded that botulinum toxin could be used as an effective treatment for reducing nocturnal bruxism and myofascial pain in patients with bruxism.