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

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

OBJECTIVE

To systematically review the literature regarding the concordance of sleep bruxism (SB) between monozygotic (MZ) and dizygotic (DZ) twins.

METHODS

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).

RESULTS

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.

CONCLUSION

There was a higher concordance of SB in MZ twins compared to DZ twins, indicating a possible genetic influence on the condition's occurrence.

Does combining oro-facial manual therapy with bruxism neuroscience education affect pain and function in cases of awake bruxism? A pilot study

BACKGROUND

Although awake bruxism is associated with temporomandibular disorder (TMD) as well as head and neck pain, the effects of physical therapy and bruxism education to address these factors have not been investigated.

OBJECTIVE

The aim of this study was to evaluate the effects of oro-facial manual therapy and bruxism neuroscience education (BNE) on awake bruxism over a 3-week period with an open-ended follow-up questionnaire after 3 months.

METHODS

Subjects (n = 28) were randomly allocated to one of two groups, an intervention group and a control group. Data regarding disability, function and pain were collected pre- and post-assessment, with all measures administered in a single-blind fashion. Participants in both groups received six treatment sessions during this period. In addition to manual therapy, participants were provided with information on the neurophysiological mechanisms of bruxism and contributing factors. Individual behavioural guidelines and daily exercises were determined in consultation with the therapist. An introduction to a bruxism specific app (Brux.App) was also provided, which all participants used as an adjunct to their treatment.

RESULTS

The intervention group demonstrated notable improvement as indicated by their scores in the Neck Disability Index (NDI) (p = .008), Pain Disability Index (PDI) (p = .007) and Jaw Disability List (JDL) (p = .03). Furthermore, clinical assessments of the temporomandibular joint (TMJ) revealed a significant progress in terms of mouth opening (p = .03) and lateral jaw movement (laterotrusion) (p = .03). The mechanical pain threshold (PTT) of both the masseter (p = .02) and temporalis muscle (p = .05) also showed significant improvement. At 3-month follow-up, the questionnaire revealed that the majority of the intervention group (13/15, 87%) reported a benefit from the treatment.

CONCLUSION

The reduction in pain and disability together with improvement in function and increased coping suggest a potential modification of awake bruxism through specialised musculoskeletal intervention and BNE tailored to the individual patient.

Risk of Dental Implant Failures May Be Higher in Bruxers Than Nonbruxers

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION

Häggman-Henrikson B, Ali D, Aljamal M, Chrcanovic BR. Bruxism and dental implants: A systematic review and meta-analysis. J Oral Rehabil. 2024 Jan;51(1):202-217. 10.1111/joor.13567. Epub 2023 Aug 17. PMID: 37589382.

SOURCE OF FUNDING

None.

TYPE OF STUDY/DESIGN

Systematic review with meta-analysis.

Sleep bruxism: The past, the present, and the future-evolution of a concept

BACKGROUND

The concept of sleep bruxism (SB) has evolved exponentially over the past several decades. Many theories and hypotheses have been proposed as to the definition, pathophysiology, and management of SB, from the early 1960s through the present. The role of peripheral factors, such as dental occlusion, in the pathogenesis of SB has been discarded.

TYPES OF STUDIES REVIEWED

The authors searched several electronic databases (ie, PubMed, Google Scholar, Web of Science, Embase, and Ovid MEDLINE) for studies on bruxism. The search was conducted from January 1961 through May 2023 and yielded 4,612 articles, of which 312 were selected for comprehensive review after eliminating duplicates and nonfocused articles.

RESULTS

There has been an evident progressive shift from the role of peripheral factors, such as dental occlusion, to more central factors, such as the involvement of a central pattern generator as well as the autonomic nervous system, in the genesis of bruxing movements. There is continued robust interest in the dental community to elucidate the contributing factors involved in SB.

CONCLUSIONS AND PRACTICAL IMPLICATIONS

The neurophysiology of SB appears to be leaning more toward central rather than peripheral factors. There is increasing evidence of the role of the autonomic nervous system, genetics, and comorbidities in the genesis of SB. The scientific literature seems to refute the role of dental occlusion in the causation of bruxing movements. As per the literature, there has been a paradigm shift in the definition and genesis of SB and its possible dental implications and management, which also highlights the need for succinct scientific studies in this regard.

Probable sleep and awake bruxism in adolescents: A path analysis

BACKGROUND

Bruxism has a multifactorial etiology, including the influence of sleep characteristics and chronotypes.

AIM

To identify the pathways that influence the occurrence of probable sleep bruxism (PSB) and probable awake bruxism (PAB) in adolescents.

DESIGN

A total of 403 adolescents, aged 12-19 years, participated in the study. Parents/caregivers filled out a questionnaire about sociodemographic issues and the adolescent's health conditions, and the adolescents about sleep characteristics, occurrence of bruxism (based on previous study and the International Consensus of Bruxism), and chronotype (Circadian Energy Scale). Clinical examinations were performed. Statistical analysis included descriptive analysis and path analysis.

RESULTS

PSB and PAB are related to each other, with moderate and positive correlation (β = .390). Poor sleep quality and higher household income had a direct effect on both PSB (β = -.138; β = .123, respectively) and PAB (β = -.155; β = .116, respectively). Chronotype had a direct effect on PSB, in such a way that adolescents with a morningness chronotype tend to have PSB (β = -.102). Adolescents that drool on the pillow (β = .184) and/or have agitated sleep (β = .104) tend to have PSB.

CONCLUSION

Poor sleep quality, household income, morningness chronotype profile, drooling on the pillow, and agitated sleep influence the paths taken by PSB. PAB was influenced by the quality of sleep and family income.

Smartphone application to report awake bruxism: Development and testing of the Swedish version and a pilot study to evaluate family history in young adults and their parents

BACKGROUND

Together with psychosocial and hereditary factors, bruxism is a possible risk factor for orofacial pain. Bruxism is defined as a masticatory muscle activity characterized by repetitive or sustained tooth contact, or by bracing or thrusting of the mandible. A smartphone application to report awake bruxism (AB) has been developed and translated into more than 25 languages.

OBJECTIVE(S)

To translate the application into Swedish, adapt it to Swedish culture and conduct a study to evaluate the usability of the application for studies on family history and associated risk factors.

METHODS

Translation and cultural adaption of the Swedish version of the application (BruxApp) was carried out in a four-step sequential process. Ten young adults (22-30 years) were recruited together with ten parents (42-67 years) and reported their AB with the application over two seven-day periods. Pain, stress and parafunctional behaviours were assessed by questionnaires.

RESULTS

The back translation check showed minimal discrepancies between the translation and the English version. Participants did not report any problems with the application. Response rates for both groups were 65%. A difference in frequency of AB was shown between young adults and parents (22.0% vs. 12.5%, p < .001). A positive moderate correlation was found between AB and stress (r = 0.54, p = .017).

CONCLUSION

The use of application strategies enables data collection on AB which can be used in both clinical and research settings. The results suggest that the Swedish version is ready for implementation and for studies on the relationships between AB, family history and psychosocial factors.

Bruxism and dental implants: A systematic review and meta-analysis

BACKGROUND

Overload from bruxism may affect survival of dental implants.

OBJECTIVES

To evaluate implant failure and marginal bone loss (MBL) in patients presenting with probable bruxism compared to non-bruxers. The study was registered in PROSPERO (CRD42021238397).

METHODS

An electronic search September 2022 in PubMed/Medline, Web of Science and Science Direct was combined with a hand search. Two independent reviewers carried out abstract screening, full-text assessment, quality assessment (National Institutes of Health tool) and data extraction. Only studies that provided information on self-report and clinical examination needed for the diagnosis of at least 'probable' bruxism were included. A pairwise random-effect meta-analysis was carried out.

RESULTS

In total 1338 studies were identified, and after screening and full-text assessment 27 studies that presented data on 2105 implants in probable bruxers and 10 264 implants in non-bruxers were included, with 138 and 352 implant failures in respective groups. the meta-analysis showed that implants placed in probable bruxers had a higher risk of failure than in non-bruxers (OR 2.189; 95% CI 1.337, 3.583, p = .002). A meta-regression showed that follow-up time did not affect this OR. Eighteen studies provided general data on MBL but did not report results separated between bruxers and non-bruxers. Therefore, an analysis of MBL was not possible.

CONCLUSION

The results of the present systematic review show that implants placed in probable bruxers present a significantly higher risk of failure than implants placed in non-bruxers. This should be considered in treatment planning and management of implant patients.

Awake bruxism in temporomandibular disorders patients referred to tertiary care: A retrospective study on its assessment and TMD management

BACKGROUND

Bruxism is defined as a repetitive jaw-muscle activity characterised by clenching or grinding of the teeth and/or by bracing or thrusting of the mandible. Bruxism can occur during sleep (sleep bruxism, SB) or during wakefulness (awake bruxism, AB). To date, the effect of AB on the purported negative consequences of bruxism has remained unclear.

OBJECTIVES

The assessment of AB, its relation to temporomandibular disorders (TMD) treatment modalities, and their possible outcomes were investigated among TMD patients resistant to treatment in primary care and referred to a tertiary care clinic.

METHODS

The records of 115 patients were studied. Patients were referred to the Head and Neck Centre, Department of Oral and Maxillofacial Diseases, Helsinki University Central Hospital, for TMD treatment between 2017 and 2020. The data derived from the eligible patients' records included the following: background data (age and sex), referral data (reason and previous treatment), medical background (somatic and psychiatric), clinical and possible radiological diagnoses at a tertiary care clinic, treatment modalities for masticatory muscle myalgia, bruxism assessment, its possible treatment modalities and their outcomes, and overall management outcome. We analysed the outcomes of single treatment modalities and combined groups of modalities. For the demographic data, the Chi-squared test and Fischer's Exact test were used to determine the associations between the categorical variables. A Sankey-diagram was used to describe the flow of treatment.

RESULTS

Temporomandibular joint-pain-dysfunction syndrome (K07.60) was the most frequent single reason to refer a patient to tertiary care (17.4%). At referral, men had myalgia (M79.1) significantly more often (p = .034) than women. Similarly, men had depression (p = .002) more often and other psychiatric diagnoses (p = .034). At tertiary care, the presence of AB was assessed in 53.9%, and self-reported AB was recorded in 48.7%. In patients with possible AB, those who were prescribed neuropathic pain medication showed significantly less improvement in symptoms (p = .021) than those who underwent splint therapy (p = .009). Overall, half of the patients showed overall improvement in their TMD symptoms from the treatment combinations.

CONCLUSION

Despite several treatment modalities, only half of the patients showed improvement in their symptoms in the present study. A standardised assessment method encompassing all factors contributing to bruxism behaviours and their consequences is suggested.

Standardised Tool for the Assessment of Bruxism

OBJECTIVE

This paper aims to present and describe the Standardised Tool for the Assessment of Bruxism (STAB), an instrument that was developed to provide a multidimensional evaluation of bruxism status, comorbid conditions, aetiology and consequences.

METHODS

The rationale for creating the tool and the road map that led to the selection of items included in the STAB has been discussed in previous publications.

RESULTS

The tool consists of two axes, specifically dedicated to the evaluation of bruxism status and consequences (Axis A) and of bruxism risk and etiological factors and comorbid conditions (Axis B). The tool includes 14 domains, accounting for a total of 66 items. Axis A includes the self-reported information on bruxism status and possible consequences (subject-based report) together with the clinical (examiner report) and instrumental (technology report) assessment. The Subject-Based Assessment (SBA) includes domains on Sleep Bruxism (A1), Awake Bruxism (A2) and Patient's Complaints (A3), with information based on patients' self-report. The Clinically Based Assessment (CBA) includes domains on Joints and Muscles (A4), Intra- and Extra-Oral Tissues (A5) and Teeth and Restorations (A6), based on information collected by an examiner. The Instrumentally Based Assessment (IBA) includes domains on Sleep Bruxism (A7), Awake Bruxism (A8) and the use of Additional Instruments (A9), based on the information gathered with the use of technological devices. Axis B includes the self-reported information (subject-based report) on factors and conditions that may have an etiological or comorbid association with bruxism. It includes domains on Psychosocial Assessment (B1), Concurrent Sleep-related Conditions Assessment (B2), Concurrent Non-Sleep Conditions Assessment (B3), Prescribed Medications and Use of Substances Assessment (B4) and Additional Factors Assessment (B5). As a rule, whenever possible, existing instruments, either in full or partial form (i.e. specific subscales), are included. A user's guide for scoring the different items is also provided to ease administration.

CONCLUSIONS

The instrument is now ready for on-field testing and further refinement. It can be anticipated that it will help in collecting data on bruxism in such a comprehensive way to have an impact on several clinical and research fields.

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

BACKGROUND

With time, due to the poor knowledge on it epidemiology, the need to focus on awake bruxism as a complement of sleep studies emerged.

OBJECTIVE

In line with a similar recent proposal for sleep bruxism (SB), defining clinically oriented research routes to implement knowledge on awake bruxism (AB) metrics is important for an enhanced comprehension of the full bruxism spectrum, that is better assessment and more efficient management.

METHODS

We summarised current strategies for AB assessment and proposed a research route for improving its metrics.

RESULTS

Most of the literature focuses on bruxism in general or SB in particular, whilst knowledge on AB is generally fragmental. Assessment can be based on non-instrumental or instrumental approaches. The former include self-report (questionnaires, oral history) and clinical examination, whilst the latter include electromyography (EMG) of jaw muscles during wakefulness as well as the technology-enhanced ecological momentary assesment (EMA). Phenotyping of different AB activities should be the target of a research task force. In the absence of available data on the frequency and intensity of wake-time bruxism-type masticatory muscle activity, any speculation about the identification of thresholds and criteria to identify bruxers is premature. Research routes in the field must focus on the improvement of data reliability and validity.

CONCLUSIONS

Probing deeper into the study of AB metrics is a fundamental step to assist clinicians in preventing and managing the putative consequences at the individual level. The present manuscript proposes some possible research routes to advance current knowledge. At different levels, instrumentally based and subject-based information must be gathered in a universally accepted standardised approach.

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

BACKGROUND

Bruxism is a masticatory muscle activity occurring during sleep or wakefulness, involving grinding and clenching of teeth and/or jaw bracing. As yet, the aetiology, epidemiology and consequences of awake bruxism (AB) are largely unknown.

OBJECTIVES

The aims of the study were to AB behaviours using a novel bruxism screener (BruxScreen) questionnaire part and Ecological Momentary Assessment (EMA; BruxApp©) on AB behaviours, and to investigate AB's prevalence among masticatory muscle myalgia patients and non-patients.

METHODS

Altogether, 115 participants (masticatory myalgia patients referred to a specialist clinic (n = 67) and non-patients (n = 46)) filled in a bruxism screener questionnaire to report bruxism behaviours and jaw symptoms. A selection of both groups did a week-long EMA (patients n = 12, non-patients n = 11) to report AB behaviours. The chi-squared test was used to determine group differences in categorical variables. A logistic regression model was fitted to study the probability of AB.

RESULTS

According to BruxScreen, bruxism behaviours and jaw symptoms were more frequent in patients than in non-patients (p < .001). Based on EMA, 14.6% of the behaviour in patients was tooth clenching; for non-patients, this was 0.5% (p < .000). Relaxed muscles were reported by patients and non-patients at 20.6% and 56.4%, respectively (p < .021). Logistic regression, adjusted by age and sex, revealed that patients reported AB 5 times more often than non-patients (OR 4.8, 95% CI 2.1-11.2).

CONCLUSION

Awake bruxism behaviours are significantly more frequent in masticatory muscle myalgia patients than non-patients and associate with frequent bruxism-related symptoms. Self-reported teeth clenching seems to be the most significant sign of AB behaviour.

A worldwide bibliometric analysis of the research trends and hotspots of bruxism in adults during 1991-2021

BACKGROUND AND OBJECTIVES

With the increasing attention to bruxism, the research on bruxism is increasing rapidly. However, there is still a lack of systematic bibliometric analysis in the field of bruxism in adults. This study aimed to comprehensively explore and visualize the global trends and research hotspots in the field of bruxism in adults during 1991-2021.

METHODS

The study searched the literature published during 1991-2021 in the Web of Science Core Collection database without language restrictions. VOSviewer, CiteSpace and Microsoft Excel were applied to analyse the authors, institutions, journals, countries, cited references, keywords and other information of the included publications, and construct visualized cooperation networks.

RESULTS

A total of 878 articles were finally included. The top two most productive authors in the past 30 years were Lobbezoo F and Manfredini D. ACTA-Amsterdam, Univ Sao Paulo, Univ Helsinki, Univ Padua, Univ Montreal, et al. were prominent institutions in this field. Journal of Oral Rehabilitation made outstanding contributions in this field. The United States produced the most documents in this field, followed by Brazil. Both countries and authors cooperated closely around the world. The two most cited articles focused on the definition, assessment and classification of bruxism. In recent years, diagnostic criteria and stress have begun to receive a lot of attention.

CONCLUSION

From 1991 to 2021, the attention to bruxism in adults continued to increase. Diagnostic criteria and stress may be potential research hotspots in this field. This study references relevant scholars on development trends and research hotspots.

Annual review of selected scientific literature: A report of the Committee on Scientific Investigation of the American Academy of Restorative Dentistry

The Scientific Investigation Committee of the American Academy of Restorative Dentistry offers this review of the 2022 dental literature to briefly touch on several topics of interest to modern restorative dentistry. Each committee member brings discipline-specific expertise in their subject areas that include (in order of the appearance in this report): prosthodontics; periodontics, alveolar bone, and peri-implant tissues; dental materials and therapeutics; occlusion and temporomandibular disorders; sleep-related breathing disorders; oral medicine and oral and maxillofacial surgery; and dental caries and cariology. The authors focused their efforts on reporting information likely to influence the daily dental treatment decisions of the reader with an emphasis on innovations, new materials and processes, and future trends in dentistry. With the tremendous volume of literature published daily in dentistry and related disciplines, this review cannot be comprehensive. Instead, its purpose is to update interested readers and provide valuable resource material for those willing to subsequently pursue greater detail on their own. Our intent remains to assist colleagues in navigating the tremendous volume of newly minted information produced annually. Finally, we hope that readers find this work helpful in managing patients.

Relationship between bruxism and mandibular bone modifications based on medical imaging: a scoping review

OBJECTIVES

This scoping review aimed to assess the current state of knowledge regarding the relationship between bruxism and changes in density or volume of mandibular bone, based on medical imaging.

METHODS

Literature review was conducted following the PRISMA-ScR protocol. PubMed, Web of Science and Cochrane library databases were searched for peer-reviewed articles by two blinded reviewers. Studies based on the evaluation of mandibular bone density and/or bone volume with imaging examination in adult patients were examined. The selected articles were summarized in PICOS tables and assessed for methodological quality.

RESULTS

Nine articles were included, according to the inclusion criteria. They showed that bruxer patients had more bony exostoses of the mandibular angle, smaller condyles, and morphological changes for cancellous and cortical mandibular bone compared to non-bruxer patients.

CONCLUSION

Bruxism seems to induce morphological and anatomical changes in the different regions of the mandibular bone (condyles, mandibular angle, mandible body). Given the heterogeneity of the included studies, these results should be interpreted with caution. Further studies are needed to support these results, in particular via the analysis of three-dimensional imaging to overcome the limitations of panoramic radiograph.

Aspects of Dental Occlusion Assessed with the T-Scan System among a Group of Romanian Dental Students in a Cross-Sectional Study

This study evaluated the occlusal relationships in students with bruxism, using the T-Scan III system, and their correlation with the activity of the masticatory muscles assessed through surface electromyography (sEMG). The study group was divided into two subgroups (based on self-reporting): 20 participants with possible bruxism and 20 participants without possible bruxism; all participants underwent the following evaluations: sEMG recordings using the dia-BRUXO device for masticatory muscles assessment, as well as static and dynamic occlusion using the T-SCAN III system. The analysis of the maximum intercuspidal (MI) position revealed a positive moderate association between the values of the occlusal forces in MI distributed along the two hemiarches, and the number of grinding events during daytime, which was statistically significant (p < 0.05). The analysis of protrusion movements reflected statistically significant differences between the non-working interferences and sEMG parameters specific to bruxism (p < 0.05). The analysis of laterotrusion movements indicated that participants with anterolateral guidance presented higher values of awake bruxism indexes and higher values of clenching events during nighttime. For all three mandibular movements, their duration was higher for the study group compared to the control group. Therefore, this study confirmed the utility of sEMG recordings in the bruxism diagnosis process, as well as the association between dental occlusion and bruxism.