The relationship of bruxism with craniofacial pain and symptoms from the masticatory system in the adult population

Students' awareness of the bruxism causes, effects and therapies

Objectives

Bruxism is a repetitive activity of the masticatory muscles characterized by clenching or grinding teeth and/or mandibular stiffening. Bruxism manifests itself in two forms: during sleeping and waking. The etiology of bruxism is multifactorial. The treatment of bruxism is mainly based on making the patient aware of the presence of the condition. The aim of the study was to assess knowledge on the causes and the effects of bruxism among Polish students as well as the possible management.

Materials and methods

The anonymous online survey was conducted among students (aged between 18 and 25 years old) of universities across Poland, using the Google Forms platform. The survey contained questions concerning bruxism causes, effects and therapies. All variants of answers in these questions contained true information about bruxism.

Results

The study found significant differences in awareness of bruxism among genders in favor of females. The awareness of bruxism among population residing in cities and in villages was comparable (p > 0.05). However, the results should be taken with care due to limited number of students that participated in the study and uneven gender distribution among urban and village residents.

Conclusions

Within the limitations of the study it can be concluded that the knowledge of bruxism among Polish students is higher in comparison with the findings from the literature, as well as the superiority of women's awareness of bruxism over men. Future studies should be conducted on greater student population, with even distribution of participants among country areas and variety of universities.

Significance

The findings may indicate the need for further education of male young adults, on bruxism causes, possible effects and therapies to increase their awareness of bruxism and encourage early diagnosis and treatment.

Associations between Bruxism, Stress, and Manifestations of Temporomandibular Disorder in Young Students

Bruxism is a repetitive activity of the masticatory muscles, which determine teeth grinding or clenching, associated with rigidity, bracing, or thrusting of the mandibula. The aim of this study was to determine the prevalence of possible bruxism in 328 students attending the Faculty of Dental Medicine, University of Medicine and Pharmacy of Craiova, and its associations with stress and other manifestations of the temporo-mandibular disorder. This was a questionnaire-based study to collect information on self-evaluation of bruxism presence, frequency of specific episodes, stress, anxiety, and other manifestations of temporo-mandibular disorder. Self-evaluated bruxism was identified in 39.33% from the entire study group, allowing us to define two subgroups for further analysis. Sleep bruxism was present in 16.28% of participants; awake bruxism was present in 68.99%, while 14.73% of participants presented a combined form. The main manifestation of bruxism was reported as teeth grinding. Fatigue was identified as a common clinical sign of bruxism and temporo-mandibular disorder. Group distribution analysis (Chi-Square) indicated significant associations between bruxism and stress, panic, restlessness, or increased stress during the COVID-19 pandemic (p < 0.05). Bruxism, and especially awake bruxism, has increased in prevalence among young students, and it has been associated with increased levels of stress.

Efficacy of botulinum-A for nocturnal bruxism pain and the occurrence of bruxism events: a meta-analysis and systematic review

The purpose of this study was to explore the treatment efficacy of botulinum-A (BTX-A) in nocturnal bruxism. Five electronic databases (PubMed, Web of Science, Cochrane, Embase and Clinical Trials) were searched to identify related randomised controlled trials up to September 1, 2020. Five evaluation indices were extracted, namely, the pain at rest and at chewing (PR and PC), the number of bruxism events (NBE) and the self-assessment by patients (SA), to assess the treatment efficacy of BTX-A in bruxism. All data analyses were conducted using Review Manager (Version 5.3; The Cochrane Collaboration, London, United Kingdom). Six studies were included in this review. The sample was composed of 148 participants. Compared with the placebo group, the BTX-A group showed the significantly improved the PR index scores (MD, 1.16 cm; 95%CI, 0.65 to 1.67 cm; p < 0.00001), slightly improved the PC index scores (SMD, 0.25; 95%CI -0.14 to 0.64; p = 0.21), and the NBEs were significantly decreased in the before-injection group compared with that in the after-injection group (MD, 1.72; 95%CI, 0.60 to 2.85; p = 0.003). The results of this study suggest that BTX-A possesses significant therapeutic efficiency for the relief of pain and events of bruxism. However, whether the events of bruxism would recur or rebound after botulinum toxin injection needs more follow-up clinical evidence.

Polysomnographic characteristics of sleep-related bruxism: What are the determinant factors for temporomandibular disorders?

This study aimed to evaluate the clinical and polysomnographic characteristics of sleep bruxism (SB) and delineate the determinant factors for temporomandibular disorders (TMD). Forty-six patients were allocated into the SB group (n = 26) and control group (n = 20). The signs and symptoms of TMD were recorded using the Research Diagnostic Criteria for TMD. Patients underwent a full-night polysomnographic recording and masseter and temporal muscle electromyographic recordings. Clinical and polysomnographic data in patients with SB were analyzed in relation to TMD. The presence of TMJ sounds was significantly correlated with the number of bruxism bursts. Intra-articular pain in the TMJ was neither correlated with clinical nor polysomnographic parameters in patients with SB. Lower sleep efficiency in patients with SB was caused by a higher number of bruxism episodes. Morning headaches were associated with the severity of SB during rapid eye movement sleep.

A study to evaluate psychological and occlusal parameters in bruxism

Purpose

To evaluate the role of anxiety/depression and occlusal factors in bruxism using Hospital Anxiety and Depression Scale and T-Scan III respectively.

Methods

The present case control study was comprising of a group of thirty patients with bruxism (Group Br) and 30 healthy individuals as control group (Group NBr). Subjects were selected from outdoor patients visiting the dental unit with the chief complaint of wearing off/sensitivity of all the teeth due to habitual grinding. The cases were selected by using the diagnostic criteria as given by the American Academy of Sleep Medicine (AASM). Further based on similarities of age and gender, controls were selected. Tooth wear index was recorded using an index given by Ekfeldt et al. Hospital Anxiety and Depression Scale (HADS) questionnaire was administered to both the groups to evaluate anxiety and depression. Recording of occlusal parameters in both the groups was done digitally by using T-Scan III. Statistical analysis was done by using student's t-test, chi square test and Mann Whitney U test.

Results

Group Br had significantly greater mean tooth wear index (22.24 ± 11.5) than group NBr (5.17 ± 3.30). Group Br had significantly higher anxiety (9.03 + 1.87/7.17 + 1.82) and depression scores (8 + 1.93/6.17 + 1.23) as compared to NBr. The disclusion time of group Br was 0.652 ± 0.749 and that of group NBr was 0.247 ± 0.289 (p = 0.008).

Conclusions

Subjects with higher level of anxiety, depression and increased disclusion time may have greater predilection towards suffering from bruxism (p < 0.05).

Sleep bruxism and temporomandibular disorders: A scoping review of the literature

OBJECTIVE

To provide a scoping review of the literature by assessing all the English-language papers that investigated the relationship between sleep bruxism (SB) and temporomandibular disorders (TMDs).

STUDY DATA AND SOURCES

A search was performed in the National Library of Medicine (PubMed) and Scopus databases, in order to identify all the articles published assessing the relationship between SB and TMDs, by several different approaches. The selected articles were then structurally read and summarized in PICO tables. The articles were selected independently by the two authors.

STUDY SELECTION

Out of 185 references that were initially retrieved, 47 articles met the inclusion criteria and were thus included in the review. The studies were divided into four categories based on the type of SB assessment: 1. questionnaire/self-report (n = 26), 2. clinical examination (n = 7), 3. electromyography (EMG) (n = 5), and 4. polysomnography (PSG) (n = 9).

CONCLUSIONS

Studies based on questionnaire/self-report SB featured a low specificity for SB assessment, and in general they found a positive association with TMD pain. On the contrary, instrumental studies (i.e., electromyography, polysomnography) found a lower level of association or even a negative relationship between SB and TMD pain. Findings from this updated review confirmed the conclusions of a previous review by Manfredini & Lobbezoo, suggesting that literature findings on the relationship between SB and TMDs are dependent on the assessment strategies that are adopted for SB. Future studies should consider SB as a multifaceted motor behavior that must be evaluated in its continuum spectrum, rather than using a simplified dichotomous approach of presence/absence.

Evaluation of Changes in Depression Levels of Bruxism Patients Treated With Botulinum Toxin-A

Aim:

Bruxism is defined as the involuntary recurrent masticatory muscle activity characterized by gnashing, grinding, clenching of teeth, and/or pushing the mandible. Factors creating its etiology are peripheral (morphological) or central (physiopathological and physiological), and exogenous. Recently, among physiological factors, depression and bruxism were considered to be related. A definitive treatment method does not exist for bruxism; however, botulinum toxin-A (BT-A) application is an up-to-date and effective way of treatment. The present study is aimed to evaluate the levels of depression in bruxism patients treated with BT-A application.

Materials and Methods:

A total of 25 individuals (23 females and 2 males) who were diagnosed as bruxism patients were included in the study. 25 U of BT-A for each masseter muscle was injected into the patients. Patients were prospectively observed for a possible change in depression levels by using Beck’s Depression Inventory. The inventory was implemented before and six months after the BT-A application. Depression levels before and six months after the injection were compared. A paired t-test was used to compare “before” and “after” treatment values. One-way analysis of variance and post-hoc Tukey tests were used to evaluate the change in Beck’s Depression Inventory scores according to age groups.

Results:

The mean total score was 7.80 ± 8.10 before the treatment and 7.16 ± 6.52 six months after the treatment. The decrease in the mean score was not statistically significant ( P > .05).

Conclusion:

In conclusion, despite the decrease in the mean Beck’s Depression Inventory scores, a statistically significant decrease in the depression levels of patients was not observed.

Efficacy of botulinum toxin in the management of temporomandibular myofascial pain and sleep bruxism

Objectives

This study sought to evaluate the efficacy of injecting botulinum toxin into the masseter and temporal muscles in patients with temporomandibular myofascial pain and sleep bruxism.

Materials and Methods

The study was conducted based on a clinical record review of 44 patients (36 females and eight males; mean age, 35.70±12.66 years). Patients who underwent the injection of botulinum toxin into the masseter and temporal muscles for the management of temporomandibular myofascial pain and sleep bruxism were included in the study. Patients were diagnosed based on the Diagnostic Criteria for Temporomandibular Disorders. Sleep bruxism was diagnosed according to the criteria defined by the American Academy of Sleep Medicine. The values of the visual analogue scale (VAS) and range of jaw motion, including unassisted maximum mouth opening (MMO), protrusion, and right and left laterotrusion, were observed preoperatively and postoperatively at one-, three-, and six-month follow-up visits.

Results

MMO, movements of the right and the left laterotrusion, and protrusion increased significantly (P<0.05), while VAS ratings decreased significantly at the three follow-up points relative to baseline values (P<0.05).

Conclusion

Botulinum toxin is an effective treatment for patients with temporomandibular myofascial pain and sleep bruxism.

Bruxism, Related Factors and Oral Health-Related Quality of Life Among Vietnamese Medical Students

Although bruxism is a common issue with a high prevalence, there has been a lack of epidemiological data about bruxism in Vietnam. This cross-sectional study aimed to determine the prevalence and associated factors of bruxism and its impact on oral health-related quality of life among Vietnamese medical students. Bruxism was assessed by the Bruxism Assessment Questionnaire. Temporomandibular disorders were clinically examined followed by the Diagnostic Criteria for Temporomandibular Disorders Axis I. Perceived stress, educational stress, and oral health-related quality of life were assessed using the Vietnamese version of Perceived Stress Scale 10, the Vietnamese version of the Educational Stress Scale for Adolescents, and the Vietnamese version of the 14-item Oral Health Impact Profile, respectively. The prevalence of bruxism, sleep bruxism, awake bruxism, and both conditions in Vietnamese medical students were 51.2%, 38.2%, 23.4%, and 10.4% respectively. Stress, temporomandibular joint pain, masticatory muscle pain, and tooth attrition were associated with the presence of bruxism. Vietnamese medical students were negatively affected by bruxism in terms of oral health-related quality of life.

Childhood Trauma, Quality of Life, Sleep Quality, Anxiety and Depression Levels in People with Bruxism

Introduction

The aim was to investigate the relation between sociodemographic features, anxiety, depression, sleep quality, childhood trauma experiences, and quality of life and bruxism determining the risk factors in people with bruxism.

Methods

A total of 200 people were included in the study. Of the patients, 100 were diagnosed with bruxism and 100 were included in the control group. Sociodemographic Data Form, Hospital Anxiety Depression Scale (HAD), The Pittsburgh Sleep Quality Index (PSQI), Childhood Trauma Scale (CTS), Short Form-36 Quality of Life Scale (SF-36) were used.

Results

While there was no significant difference between the case group and the control group in terms of age, gender, marital status, and working status, there was a significant difference between educational levels. When the groups were compared a significant difference was found with regard to HAD-A (p<0.05), HAD-D (p<0.01), PSQI (p<0.01) and CTS (p<0.05) scores. While a significant difference was found when KF-36 subscales were examined, with regard to Physical Function (p<0.01), Pain (p<0.05), Social Function (p<0.05) and Mental Health (p<0.01) scores, no significant difference was detected between the subscales of Role Strength (p>0.05), General Health (p>0.05), Vital Energy (p>0.05) and Emotional Role (p>0.05). Regression analysis shows, (PSQI), HAD-D CTS scores predicted bruxism.

Conclusion

Higher depression scale scores, bad sleep quality, traumatic childhood experiences increase the risk for bruxism. Paying attention to the mental state of people diagnosed with bruxism in the treatment process and incorporating the psychiatrists in this process may increase the success rate of the treatment.

Bruxism, temporomandibular dysfunction and cervical impairments in females - Results from an observational study

PURPOSE

Bruxism is highly prevalent and defined as abnormal habitual mouth activity including clenching of the teeth and increased jaw muscle activity. The association between bruxism and temporomandibular dysfunction (TMD) is debated, in particular the association between cervical spine impairments, bruxism, and TMD. Hence the purpose of this study was to identify the relationship between bruxism, TMD, and cervical spine impairments.

METHODS

This observational study categorized 55 female volunteers suitable for evaluation to a bruxism (n = 33) or non-bruxism group (n = 22) based on comprehensive screening using questionnaires and visual observation of the mouth by 2 independent dentists. Following this, both groups were evaluated for TMD, severity and location of head/neck pain, neck disability index (NDI), cervical spine impairments, and tissue mechanosensitivity. Regression analysis was used to evaluate the relationship between bruxism, TMD severity, and cervical impairments.

RESULTS

Coefficients of pain and bruxism were significantly associated with NDI scores (0.43, p < 0.001; 3.24, p = 0.01) with large and medium sized effects. As a consequence, both severity of TMD and bruxism status are independently associated with cervical impairments. Having TMD is an independent predictor for head/neck pain and cervical impairments. Pain associated with movement tests and tissue mechanosensitivity was found to be an important factor in bruxism.

CONCLUSION

Clinicians need to be aware that signs of cervical movement impairment are not likely to be associated with bruxism, rather they should focus on improving orofacial function and tissue mechanosensitivity.

Psychosocial Predictors of Bruxism

OBJECTIVES

The study aimed to investigate the psychosocial predictors of bruxism. The association of various psychosocial factors such as alexithymia, emotional processing, state and trait anxiety, and stress with awake bruxism was analysed.

METHODS

The study involved 52 volunteers diagnosed with awake bruxism. The toolkit that was used included the Toronto Alexithymia Scale (TAS-20), the Emotional Processing Scale (EPS), the Cohen Perceived Stress Scale (PSS-10), and the State- and Trait-Anxiety Inventory (STAI), with independent individual psychological diagnoses being made for every patient. The results were statistically analysed using IBM SPSS Statistics 24.

RESULTS

The obtained data clearly show that psychological traits-both permanent dispositions (e.g., state anxiety and alexithymia) and temporary states (e.g., trait anxiety, emotional processing deficits, and psychological stress)-are significant determinants of awake bruxism. The percentage of explained variance indicates the presence of other factors as well.

CONCLUSIONS

Psychosocial factors such as state anxiety and trait anxiety, alexithymia, and perceived stress are as important as somatic causes in the occurrence and maintenance of awake bruxism. The profile of the obtained data suggests the possibility of preventing or minimizing the symptoms of awake bruxism through properly constructed psychoprophylactic interactions.

Diagnosis and management of bruxism: Evaluation of clinical practices in France

Objective: The Evaluation of Clinical Practice (ECP) conducted with a sample of French general dental practitioners aimed to measure the methods used to diagnose and manage bruxism.Methods: The ECP was performed using a declarative online questionnaire-based anonymous survey (SurveyMonkey) of 1388 practitioners. Twenty-two questions were grouped in 5 categories: (1) Sociodemographic characteristics (Q1-6); (2) Knowledge of the prevalence and definition of bruxism (Q7-9); (3) Diagnostic approach (Q10-11) and management (Q12-Q13); (4) The use of occlusal splints (Q14-21); (5) Oral rehabilitation (Q22).Results: The answers obtained (233; 16.8%) revealed a wide disparity and insufficient diagnosis (e.g. only 41% looked for sleep disorders, 22.3% for consumption of stimulants, 3% for upper airway obstruction) and management of bruxism (e.g. only 21.9% of participants proposed cognitive-behavioral therapy).Discussion: The discrepancies detected, such as the use of inappropriate splints (30 to 70%), emphasize the need for more prompt research-to-practice transfer of new knowledge.

The correlation between sleep bruxism, salivary cortisol, and psychological status in young, Caucasian healthy adults

Objective: To analyze the association between sleep bruxism (SB), salivary cortisol, and psychological state in healthy adults.Methods: Sixty healthy students (with or without SB) were included in the study. The subjects completed a questionnaire that evaluated the presence of SB and analyzed the general and work-related psychological states and job-related frustration. Clinical examinations of TMJs and dental wear were performed. The salivary cortisol was determined using ELISA technique.Results: Subjects with SB had a general status characterized by anxiety or stress compared to subjects without SB. They also presented a work-induced depressive or anxious attitude compared to healthy individuals. The salivary cortisol levels were higher in subjects with SB and in females and were correlated with subjects' general anxiety, but not with a job-induced psychological state.Conclusion: SB is correlated with general and job-induced psychological changes. Salivary cortisol could be a non-invasive marker for the evaluation of SB severity.

The prevalence of awake bruxism and sleep bruxism in the Dutch adult population

Background

Awake bruxism and sleep bruxism are common conditions amongst adult populations, although prevalence data are scarce.

Objective

This study aimed to assess the prevalence of awake bruxism and sleep bruxism in the Dutch adult population.

Methods

As part of a large epidemiologic survey on oral health of the general Dutch adult population, a total of 1209 subjects were asked about their bruxism behaviour during the day and during their sleep. The collected data were subjected to stratified analysis by five age groups (25‐34, 35‐44, 45‐54, 55‐64 and 65‐74 years), socioeconomic status, and gender.

Results

A prevalence of 5.0% of the total population was found for awake bruxism and of 16.5% for sleep bruxism. Regarding the five age groups, prevalence of 6.5%, 7.8%, 4.0%, 3.2% and 3.0%, respectively, were found for awake bruxism, and of 20.0%, 21.0%, 16.5%, 14.5% and 8.3%, respectively, for sleep bruxism. Women reported both awake bruxism and sleep bruxism more often than men. These differences were statistically significant. Concerning socioeconomic status (SES), both awake bruxism and sleep bruxism were more often found in high SES groups, being statistically significant for awake bruxism only.

Conclusion

Sleep bruxism is a common condition in the Dutch adult population, while awake bruxism is rarer.

Bruxismo do sono: estudo de base populacional em pessoas com 18 anos ou mais na cidade de Rio Grande, Rio Grande do Sul

RESUMO: Objetivos: Avaliar a prevalência do bruxismo do sono, bem como seus principais sinais e sintomas, na cidade de Rio Grande, Rio Grande do Sul. Avaliar a associação do bruxismo do sono com sexo, idade, escolaridade e estresse psicológico. Método: O estudo foi do tipo transversal. Uma amostra representativa da população (1.280 pessoas residentes na zona urbana da cidade com idade maior ou igual a 18 anos de idade) foi entrevistada. A avaliação do bruxismo do sono foi realizada por meio de questionário baseado nos critérios diagnósticos da Classificação Internacional de Distúrbios do Sono. Resultados: A prevalência de bruxismo do sono encontrada na população foi de 8,1% (intervalo de confiança de 95% - IC95% - 6,6 - 9,5). Entre os sinais e sintomas da disfunção utilizados para o diagnóstico de bruxismo do sono, o desgaste dentário (70,3%) e a dor nos músculos mastigatórios (44,5%) foram os mais frequentemente relatados pelas pessoas que declararam ranger os dentes durante o sono. Não houve diferença significativa na prevalência de bruxismo do sono entre os sexos. A faixa etária com mais de 40 anos teve maior prevalência de bruxismo do sono. A disfunção foi associada a um maior nível de escolaridade (razão de prevalência - RP = 1,92; IC95% 1,35 - 2,72) e de estresse psicológico (RP = 1,76; IC95% 1,11 - 2,81). Conclusão: O bruxismo do sono tem uma importante prevalência na população em geral, causando diversos danos ao sistema estomatognático. O estresse psicológico é um fator de risco para essa disfunção.

Effects of Myofascial Trigger Point Dry Needling in Patients with Sleep Bruxism and Temporomandibular Disorders: A Prospective Case Series

Objectives

To investigate the effects of deep dry needling (DN) of myofascial trigger points (MTrPs) of the masseter and temporalis on pain, pressure pain threshold (PPT), pain-free maximal jaw opening and temporomandibular disorder (TMD)-related disability in patients with sleep bruxism (SB) and myofascial TMD.

Methods

Seventeen subjects (11 women, 6 men) aged 39±13 years (range 23–66) diagnosed with SB and myofascial TMD were invited to participate in this prospective case series study. Each subject received a deep DN intervention in the masseter and temporalis MTrPs. Pain intensity, PPT, pain-free maximal jaw opening and TMD-related disability were assessed before treatment, immediately after treatment and at 1-week follow-up. Jaw disability was assessed using the jaw disability checklist (JDC) at baseline and 1 week post-treatment only.

Results

One-way analyses of variance showed significant improvements in pain intensity, PPT and jaw opening (p<0.001). Post-hoc analysis revealed significant differences between baseline and post-intervention follow-up time points in pain (immediate: Cohen's d=1.72, p<0.001; 1 week: d=3.24, p<0.001), jaw opening (immediate: d=0.77, p<0.001; 1 week: d=1.02, p<0.001) and PPT in the masseter (immediate: d=1.02, p<0.001; 1 week: d=1.64, p<0.001) and temporalis (immediate: d=0.91, p=0.006; 1 week: d=1.8, p<0.001). A dependent t-test showed a significant improvement in jaw functioning, reflected by a large reduction in 1-week JDC scores relative to baseline (d=3.15, p<0.001).

Conclusions

Deep DN of active MTrPs in the masseter and temporalis in patients with myofascial TMD and SB was associated with immediate and 1-week improvements in pain, sensitivity, jaw opening and TMD-related disability.

Trial registration number

Results.

Perceived stress and bruxism in university students

BACKGROUND

Many studies have shown the correlation between bruxism and stress that affects the quality of life of university students. The present study highlights this correlation-for the first time-in a group of university students in Italy.

METHODS

We have investigated the prevalence of awake and asleep bruxism and its correlation with perceived stress in a group of 278 Italian undergraduate students (117 M). A self report questionnaire was constructed using a socio-demographic test, the Perceived Stress Scale (PSS) and the item n. 8 of the Fonseca Questionnaire for presence of bruxism.

RESULTS

The perceived stress score using PSS-10 scale was 32.2 (SD 4.6, 95% CL 31.6-32.7) for all the subjects, with significant gender difference: M = 31.2 and F = 32.9 (P = 0.0019). The prevalence for awake bruxism was 37.9% (F = 40.8%; M = 34.2%,), while for sleep bruxism was 31.8% (F = 33.3%; M = 29.1%), both without significant gender difference. A positive correlation, with significant concordance and dependence, between stress score and awake bruxism was present for male students only.

CONCLUSIONS

University students showed higher bruxism and stress levels compared to the general population, with higher stress for females, but, even if female students show higher stress, a correlation between stress and bruxism exists only for male gender. Further studies should be performed.

Prevalence of Bruxism in Patients with Different Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) Diagnoses

The relationship between bruxism and temporomandibular disorders is complex and is not yet clearly understood. The purpose of this study was to investigate the prevalence of clinically diagnosed bruxism in 212 patients with different Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) diagnoses, as compared with that in 77 sex- and age-matched TMD-free subjects. A significant association between bruxism and temporomandibular disorders emerged (p < 0.05). The highest prevalence of bruxism was found in patients with the following diagnoses: combined myofascial pain and disk displacement (87.5%); combined myofascial pain, disk displacement, and other joint conditions (73.3%); and myofascial pain (68.9%). In general, it is suggested that bruxism has a stronger relationship with muscle disorders than with disk displacement and joint pathologies, and that such a relationship seems to be independent from the presence of other RDC/TMD diagnoses along with myofascial pain.

Can palpation-induced muscle pain pattern contribute to the differential diagnosis among temporomandibular disorders, primary headaches phenotypes and possible bruxism?

BACKGROUND

The evaluation of possible differences in the distribution or characteristics of palpation-induced pain in the masticatory muscles could be valuable in terms of diagnostic assessment. The aim of this study was to evaluate the impact of different combinations of anterior temporalis (AT) and masseter palpation-induced pain in the diagnostic of temporomandibular disorder (TMD), primary headaches and bruxism.

MATERIAL AND METHODS

A total of 1200 dental records of orofacial pain adult patients were analyzed. The outcomes were dichotomously classified (presence/absence) as following: a) AT and/or masseter palpation-induced pain; b) myogenous TMD; c) temporomandibular joint (TMJ) arthralgia (arthrogenous TMD); d) migraine; e) tension-type headache (TTH); f) self-reported bruxism. Binomial logistic regression model (α = 5%) was applied to the data considering the palpation-induced muscle pain as the dependent variable.

RESULTS

Mean age (SD) were 35.7 years (13.4) for 635 included dental records (83% females). Myogenous and arthrogenous TMD, migraine, TTH and bruxism were mainly associated with, respectively, masseter palpation-induced pain (p<0.001 - OR=5.77, 95%CI 3.86-8.62), AT or masseter palpation-induced pain (p<0.001 - OR=2.39, 95%CI 1.57-3.63), bilateral AT palpation-induced pain (p<0.001 - OR=2.67, 95%CI 1.64-4.32), masseter and AT palpation-induced pain (p=0.009 - OR=1.62, 95%CI 1.12-2.33) and bilateral masseter palpation-induced pain (p=0.01 - OR=1.74, 95%CI 1.13-2.69).

CONCLUSIONS

Palpation-induced pain in the masticatory muscles may play a role in the differential diagnosis among painful TMD, primary headaches and bruxism.

Orofacial pain and headache: a review and look at the commonalities

Headache and facial pain - in particular, temporomandibular disorders (TMDs) - are very prevalent conditions in the general population. TMDs are defined as a collection of symptoms and signs involving masticatory muscles, the temporomandibular joints (TMJs), or both. The pain reported by TMD patients is typically located in the muscles of mastication, in the preauricular area, or in the TMJs. In many cases, headaches and facial pain will occur in the same patient. Much of the research relative to the relationship of these disorders focuses on statistics of association and prevalence data. This review will provide a brief description of the types and classifications of orofacial pains (OFPs), as well as point to relevant research describing the commonalities and potential comorbid nature of these maladies. Finally, several recent papers describing morphologic changes to the brain in headache and TMD individuals will be discussed in an effort to stimulate further research into the potential common pathophysiologic mechanism that may explain the comorbid nature of these disorders.

Botulinum toxin type A combined with cervical spine manual therapy for masseteric hypertrophy in a patient with Alzheimer-type dementia: a case report

OBJECTIVE

The purpose of this case study is to present the findings of combining botulinum toxin type A (BoNT-A) and cervical spine manual therapy to address masseter muscle spasticity in a patient with Alzheimer-type dementia.

CASE REPORT

A 78-year-old woman with bilateral spasticity of the masseteric regions for 2 years was referred for physiotherapy. She had trismus and bruxism, and could neither close nor open her mouth normally; thus, she was unable to be fed orally in a normal manner.

INTERVENTION AND OUTCOME

The patient underwent combined treatment with BoNT-A and cervical spine manual therapy. A medical physician (neurologist) performed the BoNT-A injections into 2 points at the center of the lower third of the masseter muscle. A physical therapist performed manual therapy interventions targeted at the cervical spine. Manual therapy started the day after the BoNT-A injection and continued for 5 sessions per week for a total period of 2 weeks. Clinical outcomes were measured including spasticity (Modified Ashworth Scale), functionality (Barthel Index), and jaw opening. Outcomes were conducted at baseline, 2 weeks after treatment, and at 2-month follow-up session after finishing the treatment. The patient improved in all of the outcomes at the end of treatment, and these results were maintained during the follow-up. After treatment, the patient was able to feed with minimal caregiver dependency because oral feeding was possible.

CONCLUSION

The patient in this study responded positively to a combination of BoNT-A and manual therapy, resulting in decreased masseter muscles spasticity and improved trismus and bruxism.

Study of temporomandibular joint disorder in older patients by magnetic resonance imaging

OBJECTIVES

To compare characteristics in older patients in a sample of the general population of those with temporomandibular joint disorder (TMJD).

MATERIALS AND METHODS

A prospective study was carried out between 2001 and 2008 in patients with TMJD. The whole sample consisted of 141 patients divided in two groups: 31 patients aged over 60 (median age 67.9, ranging from 60 to 82) and the remaining 110 patients (median age 36.3, ranging from 12 to 59) who were seeking treatment. Clinical diagnostics was confirmed by MRI. Pain intensity was rated on a visual analogue scale (VAS 0-10).

RESULTS

There was no statistical difference between average pain in older patients (6.2) and patients aged up to 59 (5.7) evaluated by VAS. There was a statistically significant difference (p = 0.002) in pain duration: older patients reported shorter duration of experienced pain (7.8 months) than patients aged up to 59 (12.2 months).

CONCLUSION

In this study, it was found that 22% were older patients with TMJD. A higher level of anxiety was shown in both patients' groups, regardless of shorter pain experience in the older patients.

Prevalence of symptoms indicative of temporomandibular disorders in adults: cross-sectional epidemiological investigations covering two decades

OBJECTIVES

The aims were (1) to study possible secular trends in the prevalence of temporomandibular disorder (TMD) symptoms in adults and (2) to analyse possible associations between TMD symptoms and background factors.

MATERIALS AND METHODS

The investigation has a repeated cross-sectional design. Three independent, randomly selected samples of ∼100 individuals in the age groups of 20, 30, 40, 50, 60 and 70 years, a total of 1704 subjects, participated in the Jönköping studies in 1983, 1993 and 2003. All the subjects were evaluated using a questionnaire and a structured interview relating to the presence of TMD symptoms. Associations between symptoms and the Anamnestic Dysfunction Index (Ai) as dependent variables and each of the independent variables, age group, gender, reported bruxism, trauma (1983), self-perceived health impairment and the year of investigation were analysed in binary logistic regression models.

RESULTS

The prevalence of the separate symptoms, apart from for TMJ clicking, did not vary to any statistically significant degree between the different examination years. However, the prevalence of recurrent headache in 20-year-old subjects rose remarkably in 2003 and an increase in the Ai I and Ai II for the whole population was observed during the 20-year period. Reported bruxism, which increased during the study period, and self-perceived health impairment were associated with most of the TMD symptoms and the Ai.

CONCLUSIONS

An increase in the prevalence of TMD symptoms expressed as Anamnestic Dysfunction Index I and II has been noted over a 20-year period.

Correlation between eye and ear symptoms and lack of teeth, bruxism and other parafunctions in a population of 1006 patients in 2003-2008

INTRODUCTION

Parafunctions (harmful habits) play a crucial role in the formation of temporo-mandibular joint (TMJ) dysfunction syndrome with disc displacement. Disorder symptoms in temporo-mandibular joints manifest themselves in the eye and ear but are usually not associated with the dysfunction of temporo-mandibular joints and that might lead to errors in diagnosis. The aim of the study was to examine the influence of missing teeth and parafunctions on the occurrence of ear and eye symptoms in patients treated in the Department of Prosthodontics of the Medical University of Lublin.

MATERIAL AND METHODS

The patient group consisted of 753 women and 253 men aged 10 to 82 years who had been treated in the Department of Prosthodontics, Medical University of Lublin in the years 2003-2008 due to various symptoms associated with temporo-mandibular joint dysfunction.

RESULTS

Eye (24.84%, n = 785) and ear (33.38%, n = 785) syndromes occur on average more often in patients with parafunctions than without them (15.98%, n = 219 and 23.29%, n = 219). However, only parafunctions involving tooth contact should be taken into consideration when diagnosing eye and ear syndromes. The data presented here show that the number of missing teeth does not have a significant influence on the frequency of occurrence of parafunctions. Parafunctions have become a very important factor in the diagnosis of diseases and pathological symptoms of eye and ear as the rate at which they occur is growing.

CONCLUSIONS

The kind of parafunction is very important. Only those involving tooth contact should be taken into consideration when diagnosing eye and ear syndromes.

Self-reported bruxism and temporomandibular disorders: findings from two specialised centres

The aims of this investigation were to report the frequency of temporomandibular disorders (TMD) diagnoses and the prevalence of self-reported awake and sleep bruxism as well as to describe the possible differences between findings of two specialised centres as a basis to suggest recommendations for future improvements in diagnostic homogeneity and accuracy. A standardised Research Diagnostic Criteria for TMD (RDC/TMD) assessment was performed on patients attending both TMD Clinics, viz., at the University of Padova, Italy (n=219; 74% women) and at the University of Tel Aviv, Israel (n=397; 79% women), to assign axis I physical diagnoses and to record data on self-reported awake and sleep bruxism. Significant differences were shown between the two clinic samples as for the frequency of TMD diagnoses (chi-square, P<0·001) and the prevalence of at least one positive response to bruxism items (chi-square, P<0·001). The more widespread use of TMJ imaging techniques in one clinic sample led to a higher prevalence of multiple diagnoses, and the higher prevalence of self-reported bruxism in patients with myofascial pain alone described in the other clinic sample was not replicated, suggesting that the different adoption of clinical and imaging criteria to diagnose TMD may influence also reports on their association with bruxism. From this investigation, it emerged that the features of the study samples as well as the different interpretation of the same diagnostic guidelines may have strong influence on epidemiological reports on bruxism and TMD prevalence and on the association between the two disorders.

Effectiveness of botulinum toxin type A treatment of neck pain related to nocturnal bruxism: a case report

OBJECTIVE

This case report describes a patient with nocturnal bruxism and related neck pain treated with botulinum toxin type A (BTX-A).

CLINICAL FEATURES

The patient was a 27-year-old man with nocturnal bruxism and difficulty in active mouth opening and chewing and neck pain at rest. His numeric pain score was 7 of 10. Surface electromyography of the temporalis and masseter muscles showed typical signs of hyperactivity, characterized by compound muscle action potential amplitude alterations.

INTERVENTION AND OUTCOME

After clinical evaluation, he was treated with BTX-A to reduce masseter and temporalis muscle hyperactivity. After 3 days of treatment with BTX-A, with each masseter muscle injected with a dose of about 40 mouse units with a dilution of 1 mL and with temporal muscle bilaterally injected with 25 mouse units with the same dilution, a decrease in bruxism symptoms was reported. Neck pain also decreased after the first treatment (visual analog scale of 2/10) and then resolved completely. After 4 weeks, electromyography showed the reduction of muscle hyperactivity with a decrease in the amplitude of the motor action potential. The same reduction in signs and symptoms was still present at assessment 3 months posttreatment.

CONCLUSION

These findings suggest that BTX-A may be a therapeutic option for the treatment of bruxism and related disorders.

Prevalence of bruxism awareness in Istanbul, Turkey

The reported prevalence of symptoms related to bruxism varies in the general population because of different investigative methodologies, operational definitions, clinical criteria, and samples of population. Awareness of bruxism in the general population is 15% to 23%, however, this rate increases to 50% to 90% in clinical studies. The aim of this study was to investigate the prevalence of self-reported symptoms associated with bruxism in Istanbul, Turkey and to analyze the correlation between bruxism and factors such as age, gender, marital status, and occupation. Seven-hundred-ninety-five (795) adult subjects who resided in the city of Istanbul were interviewed by telephone about their age, gender, marital status, occupation, and description of the prevalence of bruxism awareness. The overall prevalence of clenching teeth was 45.7% and that of grinding teeth was 21.6%. Women responded positively to the questions more often than men. The data showed significant differences between males and females, regarding clenching teeth OR: 1.41 (95% CI: 1.05-1.87), difficulty opening OR: 2.64 (95% CI: 1.63-4.26), headache on awakening OR: 2.28 (95% CI: 1.58-3.27) joint sounds OR: 1.72 (95% CI: 1.24-2.38), sore on awakening OR: 2.97 (95% CI: 1.91-4.61), influence in daily activity (OR: 2.26 CI: 1.38-3.67). Tooth wear in the married group was higher than the single group. Age distribution showed significant differences related to grinding teeth, tooth wear and joint sounds. There were statistically significant differences between bruxism and job categories. As a conclusion, this study suggest an association between bruxism and stressful events such as marital status and job problems.

Relação entre bruxismo e o grau de sintomatologia de disfunção temporomandibular

OBJETIVO: verificar a ocorrência de bruxismo em sujeitos adultos do sexo feminino com queixa de disfunção temporomandibular e sua relação com o grau de sintomatologia da disfunção. MÉTODOS: participaram deste estudo 28 mulheres na faixa etária de 19 a 56 anos, que apresentavam sintomas de disfunção temporomandibular e que não haviam realizado tratamento anterior. Todas responderam o questionário de Índice Anamnésico proposto por Fonseca et al (1994), o qual possibilita a classificação do grau de sintomatologia de disfunção temporomandibular e verificação da queixa do hábito parafuncional bruxismo; e realizaram uma avaliação odontológica, constituída de exame da musculatura mastigatória, por meio de palpação digital intra e extra-oral, inspeção das articulações temporomandibulares e exame dental. Os resultados foram analisados descritivamente e, para verificar a relação entre o grau de severidade da disfunção temporomandibular com a ocorrência de bruxismo, foram realizados o Teste de Independência do Qui-quadrado e o Teste Exato de Fisher, ambos ao nível de significância de 5%. RESULTADOS: verificou-se que o bruxismo esteve presente em 50% dos casos de disfunção temporomandibular. Não houve relação entre o bruxismo e o grau de sintomatologia de disfunção temporomandibular, estabelecido pelo Índice Anamnésico. CONCLUSÃO: os resultados deste estudo sugerem que sujeitos com sintomas de disfunção temporomandibular devem ser questionados e avaliados quanto à presença de bruxismo, independentemente do grau de sintomatologia da disfunção. Assim como deve ser realizado diagnóstico e tratamento do bruxismo em sujeitos assintomáticos de disfunção temporomandibular como forma de prevenir o desenvolvimento de lesões nas articulações temporomandibulares e demais estruturas do sistema estomatognático.

Massage therapy in the management of myogenic TMD: a pilot study

Introduction:

The Temporomandibular disorder (TMD) is greatly prevalent in the population and can be associated with bruxism. This disorder produces several signs and symptoms. Among them, pain is one of the most important because it reduces life quality and productivity of people who have such disorder. The aim of this research was to study if massage causes pain relief and/or electromyographic (EMG) changes.

Materials and methods:

The subjects were chosen by a questionnaire and divided into 2 different groups. Their ages varied from 19 to 22 years. The experimental group consisted of 6 TMD patients, who were submitted to the massage treatment and 4 EMG-sessions (the 1^st EMG-session occurred before the treatment and the others in the 1^st, 15^th and 30^th days after the treatment). The control group consisted of 6 TMD patients, who were submitted to the same 4 EMG-sessions. While EMG activity was recorded, subjects were asked to keep mandibular rest position (MRP) and to perform maximal voluntary clenching (MVC). The treatment consisted of 15 massage-sessions on face and neck and in application of Visual Analogue Scale (VAS) for measuring pain level. The massage sessions had 30 minutes of duration and were performed daily. The EMG data were processed to obtain the Root Mean Square (RMS), which were normalized by MVC.

Results:

It was demonstrated that (1) RMS-MRP of the right masseter in experimental group at the 1^st EMG-session was higher than at the 2^nd EMG-session and (2) statistically significant reduction was found for VAS values after massage session.

Conclusion:

Unfortunately the sample is insufficient to draw any conclusions, therefore, more studies regarding the use of massage in the management of myogenic TMD are necessary.

Electromyographic standardized indices in healthy Brazilian young adults and data reproducibility

The determination of normal parameters is an important procedure in the evaluation of the stomatognathic system. We used the surface electromyography standardization protocol described by Ferrario et al. (J Oral Rehabil. 2000;27:33-40, 2006;33:341) to determine reference values of the electromyographic standardized indices for the assessment of muscular symmetry (left and right side, percentage overlapping coefficient, POC), potential lateral displacing components (unbalanced contractile activities of contralateral masseter and temporalis muscles, TC), relative activity (most prevalent pair of masticatory muscles, ATTIV) and total activity (integrated areas of the electromyographic potentials over time, IMPACT) in healthy Brazilian young adults, and the relevant data reproducibility. Electromyography of the right and left masseter and temporalis muscles was performed during maximum teeth clenching in 20 healthy subjects (10 women and 10 men, mean age 23 years, s.d. 3), free from periodontal problems, temporomandibular disorders, oro-facial myofunctional disorder, and with full permanent dentition (28 teeth at least). Data reproducibility was computed for 75% of the sample. The values obtained were POC Temporal (88.11 +/- 1.45%), POC masseter (87.11 +/- 1.60%), TC (8.79 +/- 1.20%), ATTIV (-0.33 +/- 9.65%) and IMPACT (110.40 +/- 23.69 microV/microV.s %). There were no statistical differences between test and retest values (P > 0.05). The Technical Errors of Measurement (TEM) for 50% of subjects assessed during the same session were 1.5, 1.39, 1.06, 3.83 and 10.04. For 25% of the subjects assessed after a 6-month interval, the TEM were 0.80, 1.03, 0.73, 12.70 and 19.10. For all indices, there was good reproducibility. These electromyographic indices could be used in the assessment of patients with stomatognathic dysfunction.

Evaluation of the relationship between anxiety and depression and bruxism

This study examined the relationship between anxiety, depression and bruxism in 99 patients with temporomandibular disorders (TMD). Patients were divided into two groups: 58 patients with bruxism and 41 without bruxism. Symptoms of TMD were evaluated according to the Craniomandibular Index. The psychological condition of patients was assessed using the Beck Depression Inventory (BDI), the Hospital Anxiety Depression Scales (HADS) and the Hamilton Anxiety Rating Scale (HAMA). The mean anxiety and depression scores (HADS and HAMA) for patients with bruxism were statistically significant higher in patients with bruxism compared with those without bruxism. Thus, there may be an association between bruxism and higher levels of anxiety and/or depression in patients with TMD.

Temporomandibular disorders and facial pain: a psychophysiological perspective

This article presents a psychophysiological perspective on temporomandibular muscle and joint disorders (TMJD) and facial pain. After a brief introduction to TMJD, the article presents data, largely derived from work carried out in my laboratory, that address four questions: (1) What are the consequences of parafunctional activities? (2) Do TMJD patients engage in parafunctional activities? (3) Why are TMJD patients unaware of these activities? and (4) What are the implications of these findings for treatment? The findings suggest that low-level parafunctions increase pain in otherwise pain-free individuals and can produce symptoms sufficiently severe to meet the diagnostic criteria for TMJD diagnoses of myofascial pain and/or arthralgia. Patients with certain forms of TMJD report very high levels of parafunctional tooth contact. Their lack of awareness of these behaviors may arise from uncertain definitions of the term "clenching", from proprioceptive deficits, or from the presence of adjunctive behaviors. Preliminary work shows that reduction in tooth contact via habit reversal techniques may be a promising mechanism for reducing pain in these patients.

Efficacy of botulinum toxin in treating myofascial pain in bruxers: a controlled placebo pilot study

The present investigation is a preliminary double-blind, controlled placebo, randomized clinical trial with a six month follow-up period. The study aimed to assess the efficacy of type A botulinum toxin (Botox, Allergan, Inc. Irvine, CA) to treat myofascial pain symptoms and to reduce muscle hyperactivity in bruxers. Twenty patients (ten males, ten females; age range 25-45) with a clinical diagnosis of bruxism and myofascial pain of the masticatory muscles were enrolled in a double-blind, controlled placebo, randomized clinical trial, with a treatment group (ten subjects treated with botulinum toxin injections- BTX-A) and a control group (ten subjects treated with saline placebo injections). A number of objective and subjective clinical parameters (pain at rest and during chewing; mastication efficiency; maximum nonassisted and assisted mouth opening, protrusive and laterotrusive movements; functional limitation during usual jaw movements; subjective efficacy of the treatment; tolerance of the treatment) were assessed at baseline time and at one week, one month, and six months follow-up appointments. Descriptive analysis showed that improvements in both objective (range of mandibular movements) and subjective (pain at rest; pain during chewing) clinical outcome variables were higher in the Botox treated group than in the placebo treated subjects. Patients treated with BTX-A had a higher subjective improvement in their perception of treatment efficacy than the placebo subjects. Differences were not significant in some cases due to the small sample size. Results from the present study supported the efficacy of BTX-A to reduce myofascial pain symptoms in bruxers, and provided pilot data which need to be confirmed by further research using larger samples.

Association between sleep bruxism and temporomandibular disorders: a polysomnographic pilot study

The aim of this study was to verify the association between sleep bruxism (SB) and temporomandibular disorders (TMD) in a sample of 14 TMD patients and 12 healthy control subjects. All participants were evaluated using a clinical questionnaire, visual analog scale (VAS) for TMJ/muscle palpation, and by functional examination. The experimental group was divided into three TMD subgroups: joint sounds and pain, muscular tenderness, and mixed diagnosis. All participants underwent polysomnographic recording (PSG). A second clinical examination was then carried out to verify the relationship between rhythmic masticatory muscle activity and pain/tenderness on the following morning. The experimental and control groups presented VAS mean scores of 36.85 +/- 23.73 mm and 0 mm, respectively. The presence of SB was neither associated with TMD (p > 0.05) nor with pain on palpation (p > 0.05). Further research with a more representative sample of each TMD subgroup is necessary to elucidate its interaction with SB.

Dental attrition models predicting temporomandibular joint disease or masticatory muscle pain versus asymptomatic controls

AIMS

To determine whether patients with temporomandibular joint disease or masticatory muscle pain can be usefully differentiated from asymptomatic controls using multifactorial classification tree models of attrition severity and/or rates.

METHODS

Measures of attrition severity and rates in patients diagnosed with disc displacement (n = 52), osteoarthrosis (n = 74), or masticatory muscle pain only (n = 43) were compared against those in asymptomatic controls (n = 132). Cross-validated classification tree models were tested for fit with sensitivity, specificity, accuracy and log likelihood accountability.

RESULTS

The model for identifying asymptomatic controls only required the three measures of attrition severity (anterior, mediotrusive and laterotrusive posterior) to be differentiated from the patients with a 74.2 +/- 3.8% cross-validation accuracy. This compared with cross-validation accuracies of 69.7 +/- 3.7% for differentiating disc displacement using anterior and laterotrusive attrition severity, 68.7 +/- 3.9% for differentiating disc displacement using anterior and laterotrusive attrition rates, 70.9 +/- 3.3% for differentiating osteoarthrosis using anterior attrition severity and rates, 94.6 +/- 2.1% for differentiating myofascial pain using mediotrusive and laterotrusive attrition severity, and 92.0 +/- 2.1% for differentiating myofascial pain using mediotrusive and anterior attrition rates. The myofascial pain models exceeded the > or =75% sensitivity and > or =90% specificity thresholds recommended for diagnostic tests, and the asymptomatic control model approached these thresholds.

CONCLUSION

Multifactorial models using attrition severity and rates may differentiate masticatory muscle pain patients from asymptomatic controls, and have some predictive value for differentiating intracapsular temporomandibular disorder patients as well.

Sleep bruxism and temporomandibular disorder: Clinical and polysomnographic evaluation

OBJECTIVE

To seek better understanding of chronic musculoskeletal facial pain and its relation to sleep bruxism, by comparing patients with sleep bruxism, with and without temporomandibular disorder.

DESIGN

Forty sleep bruxism patients were evaluated according to the Research Diagnostic Criteria for Temporomandibular Disorders: group A-20 patients with myofascial pain, 3 men, 17 women; average age 32.7yr; mean duration of pain 4.37yr; group B-20 without myofascial pain, 5 men, 15 women; average age 30.8yr. Sleep and bruxism were evaluated in one-night polysomnography.

RESULTS

There were no statistically significant differences for bruxism and sleep variables of the two groups: number of bursts and bruxism episodes per hour, amplitude and duration of bruxism episodes, sleep efficiency and latency, percentage of non-REM and REM sleep, respiratory events, periodic limb movements, and micro-arousals.

CONCLUSIONS

The polysomnographic characteristics of patients with sleep bruxism, with and without orofacial pain, are similar. More studies are necessary to clarify the reasons why some sleep bruxism patients develop chronic myofascial pain, and others do not.

The clinical usefulness of surface electromyography in the diagnosis and treatment of temporomandibular disorders

BACKGROUND

This article presents a comprehensive review of the recent literature regarding the scientific support for the use of surface electromyography (SEMG) in diagnosing and treating temporomandibular disorders (TMDs).

TYPES OF STUDIES REVIEWED

The authors conducted a Medline search involving human studies using the key words "surface electromyography or electromyography" and "masticatory muscles or temporomandibular disorders or craniomandibular disorders." They also reviewed relevant articles regarding the clinical usefulness of SEMG based on reliability, validity, sensitivity and specificity, as well as additional references included in some of the articles.

RESULTS

The clinical use of SEMG in the diagnosis and treatment of TMD is of limited value when one considers reliability, validity, sensitivity and specificity as measurement standards. SEMG does not appear to contribute any additional information beyond what can be obtained from the patient history, clinical examination and, if needed, appropriate imaging.

CONCLUSIONS

Clinically, the determination of the presence or absence of TMD does not appear to be enhanced by the use of SEMG. However, the modality may be useful in a meticulously controlled research setting.

CLINICAL IMPLICATIONS

SEMG has limited value in the detection or management of TMD and in some instances may lead to unnecessary dental therapy as a solution for those disorders.