Temporomandibular disorder: otologic implications and its relationship to sleep bruxism

The impact of print orientation and graphene nanoplatelets on biaxial flexural strength and cytotoxicity of a 3D printable resin for occlusal splints

OBJECTIVES

3D printing found its way into various medical applications and could be particularly beneficial for dentistry. Currently, materials for 3D printing of occlusal splints lack mechanical strength compared to polymethyl methacrylate (PMMA) used for standard milling of occlusal splints. It is known that print orientation and graphene nanoplatelets (GNP) can increase biaxial strength in a variety of materials. Thus, the aim of this study was to assess if adjustment of print orientation and addition of GNP improve biaxial strength and if they affect cytotoxicity of a 3D printable resin for occlusal splints.

METHODS

Specimens were printed vertically and horizontally with a stereolithography (SLA) printer and multilayered GNP powder was added to the resin at different concentrations. Printed specimens were characterized by Raman spectroscopy, optical profilometer analysis and scanning electron microscopy. Biaxial strength was evaluated by biaxial flexural testing. Cytotoxicity of specimens on L929 and gingival stromal cells (GSC) was assessed by the toxdent test, the resazurin-based toxicity assay and live-dead staining.

RESULTS

Horizontally printed specimens showed significantly higher biaxial strength and lower deformation. GNP did not improve biaxial strength and material deformation of 3D-printed resins. None of the specimens were cytotoxic to L929 cells or GSC.

SIGNIFICANCE

Print orientation in SLA printing has a significant impact on biaxial strength and material deformation. 3D printable materials can reach comparable or even improved biaxial strength compared to PMMA when using the optimal print orientation while GNP has no beneficial effects on the biaxial strength of resins for 3D printing of occlusal splints.

Knowledge and awareness about temporomandibular disorder among dentists in India: Questionnaire study and review

AIM

Temporomandibular disorders (TMD) comprise ailments involving the jaw joint (temporomandibular joint) and its associated anatomical structures. The complexity involved in TMD is primarily due to its broad spectrum of conditions, clinical signs and symptoms variability, and multifactorial etiology. Considering the above, the present study was performed to help understand the prevailing knowledge and awareness of TMD among Indian dentists in the context of the new specialty "orofacial pain".

SETTINGS AND DESIGN

Questinnaire study and review.

MATERIALS AND METHODS

The questionnaire was distributed using a web-based portal nationwide among Indian dentists. Dentists were invited to participate, clearly stating that the intent and purpose of the questionnaire was to record the existing knowledge and awareness concerning temporomandibular disorders among Indian dentists. The questionnaire was segregated into three sections: pathogenesis, diagnosis, and management of TMDs. The questions were recorded using a Likert three-point scale (1=agree; 2=disagree; 3=not aware). 310 dentists participated in the survey, among which 105 were general dentists (BDS [Bachelor of Dental Surgery] graduates), and 205 were dentists with specialist training (MDS [Masters of Dental Surgery] graduates).

STATISTICAL ANALYSIS USED

The results obtained from the study participants was used to calculate the percentage and frequency, following which tabulations were made based on graduate type and clinical experience. The values obtained from all three sections were recorded, and the responses were analysed using Pearson's Chi-Square test with statistical significance kept at P < 0.05.

RESULTS

Results of the study disclosed that only 58.1% of general dentists and 46.8% of specialists were confident in handling temporomandibular disorder patients. Splint therapy was the preferred treatment modality for general dentists, whereas dentists with specialist training preferred occlusal rehabilitation.

CONCLUSION

The results of the current survey indicate that Indian dentists lack sufficient training in dental schools on all three sections and face difficulty diagnosing and treating TMDs.

Oral Health Implications of Obstructive Sleep Apnea: A Literature Review

BACKGROUND

Obstructive sleep apnea (OSA) is a prevalent sleep disorder characterized by repeated episodes of partial or complete obstruction of the upper airway during sleep. While the systemic implications of OSA are well documented, the dental consequences are less frequently discussed yet equally significant. This review aims to elucidate the oral health impacts of OSA, emphasizing the importance of interdisciplinary care.

METHODS

A comprehensive literature search was conducted across several databases to identify studies examining the relationship between OSA and various oral health parameters. The review included observational studies, clinical trials, and systematic reviews published in English up to January 2024.

RESULTS

OSA was significantly associated with heightened risks of bruxism, dry mouth, periodontal disease, temporomandibular joint disorders, palatal and dental changes, and alterations in taste sensation. Mouth breathing associated with OSA was a critical factor in exacerbating xerostomia and dental caries. Furthermore, the systemic inflammation induced by OSA appeared to correlate with the severity of periodontal disease. Patients using oral appliance therapy for OSA also showed notable changes in dental occlusion and required ongoing dental monitoring.

CONCLUSIONS

The findings underscore the bidirectional relationship between OSA and oral health, highlighting the need for dental professionals to be integral participants in the management of OSA. Early dental evaluation and intervention can contribute to the overall health and quality of life of individuals with OSA. The review advocates for the development of clinical guidelines to facilitate the early identification and management of OSA-related oral health issues within dental practice and encourages a collaborative approach to patient care.

Association Between Oral Behaviors and Painful Temporomandibular Disorders: A Cross-Sectional Study in the General Population

Background

Studies have reported correlations between various oral behaviors and painful temporomandibular disorders (TMD), yet comprehensive research on the independent effects of each oral behavior within the general population remains sparse.

Objective

This cross-sectional study aimed to investigate the association between painful TMD (PT) and various oral behaviors in general population.

Methods

A questionnaire survey was conducted with participants to collect data encompassing demographic characteristics, eight specific oral behaviors, and the 5 major TMD symptoms(5Ts) checklist. Participants were categorized into PT and non-PT (NPT) groups based on their responses to the 5Ts checklist. Those reporting TMJ/facial pain or headaches were assigned to the PT group, while all other participants constituted the NPT group. Both univariate and multivariate logistic regression analyses were employed to evaluate the association between individual oral behavior and the presence of PT, controlling for demographic confounders including age, sex, systemic diseases, and dental treatments history.

Results

A total of 441 valid questionnaires were received, including 156 males and 285 females. The prevalence of PT was identified to be 33.33%, with 61.00% of participants engaging in one or more types of oral behaviors. Each oral behavior was more frequently reported in the PT group compared to the NPT group. The univariate logistic regression analysis identified positive correlations between all eight oral behaviors and PT. In the multivariate logistic regression analysis, these associations persisted after adjustment for demographic confounders including age, sex, history of systemic diseases and dental treatments (P<0.01). The behaviors most strongly associated with PT were "Hold or jut jaw forward/to the side" (OR:4.478), "Hold, tighten or tense muscles without clench" (OR:3.343) and "Hold jaw in rigid or tense position" (OR:3.209).

Conclusion

The presence of oral behaviors has significant association with PT. Individuals exhibiting multiple oral behaviors are more likely to experience PT. Additional studies are needed to clarify the effects of reducing oral behaviors on pain-related symptoms.

Central effects of trigeminal electrical stimulation

This is a review of the literature on the main neuromodulation techniques, focusing on the possibility of introducing sensory threshold ULFTENS into them. Electro neuromodulation techniques have been in use for many years as promising methods of therapy for cognitive and emotional disorders. One of the most widely used forms of stimulation for orofacial pain is transcutaneous trigeminal stimulation on three levels: supraorbital area, dorsal surface of the tongue, and anterior skin area of the tragus. The purpose of this review is to trigger interest on using dental ULFTENS as an additional trigeminal neurostimulation and neuromodulation technique in the context of TMD. In particular, we point out the possibility of using ULFTENS at a lower activation level than that required to trigger a muscle contraction that is capable of triggering effects at the level of the autonomic nervous system, with extreme ease of execution and few side effects.

Predictive model for temporomandibular disorder in adolescents: Decision tree

BACKGROUND

Temporomandibular disorders (TMD) do not only occur in adults but also in adolescents, with negative impacts on their development.

AIM

To propose a predictive model for TMD in adolescents using a decision tree (DT) analysis and to identify groups at high and low risk of developing TMD in the city of Recife, PE, Brazil.

DESIGN

This cross-sectional study was conducted in Recife on 1342 schoolchildren of both sexes aged 10-17 years. The analyses were performed using Pearson's chi-squared test and Fisher's exact test, as well as the CHAID algorithm for the construction of the DT. The SPSS statistical program was used.

RESULTS

The prevalence of TMD was 33.2%. Statistically significant associations were observed between TMD and sex, depression, self-reported orofacial pain, and orofacial pain on clinical examination. The DT consisted of self-reported orofacial pain, orofacial pain on physical examination, and depression, with an overall predictive power of 73.0%.

CONCLUSION

The proposed tree has a good predictive capacity and permits to identify groups at high risk of developing TMD among adolescents, such as those with self-reported orofacial pain or orofacial pain on examination associated with depression.

Temporomandibular treatments are significantly efficient in improving otologic symptoms

Symptoms of temporomandibular disorders (TMD) could be present as otologic symptoms like earache and dizziness in some patients. In most cases, these symptoms are not recognized because otolaryngologists fail to diagnose TMD as a source of the problem. This investigation was conducted to evaluate the effect of TMD treatments on the otologic symptoms which after taking history and clinical examinations seemed to be related to TMD. In the present study, the patients who were complaining of otalgia, ear fullness, tinnitus, hearing loss, and dizziness were evaluated by an ear fellow. Forty patients who had no known otologic or other primary causes to explain their symptoms, were referred to the orofacial pain clinic with the possible diagnosis of TMD. If the diagnosis was confirmed by an orofacial pain specialist, a combination of TMD treatments was administered to each case and the patients were followed up. The results showed that following implementation of treatment protocols for TMD, more than 50% of the patients reported complete or partial recovery in the second follow-up (p < 0.05). The most common otologic symptom of the referred cases was earache, and the most common associated complaint was neck pain. All the patients had one or more parafunctional habits. This study showed that TMD treatments were significantly efficient in improving otologic symptoms partially or completely and the authors concluded that for the patients with otolaryngologic unexplained symptoms, an overhaul examination is needed to assess TMD as a possible cause of the patient complaint. It is recommended that in cases with unexplained otologic symptoms, otolaryngologists care more about the neck trigger points (TP) and ask about the patient's parafunctional habits. Otolaryngologists and dentists need to be aware of the risk of developing otologic symptoms caused by these habits or cervical TPs.

Prevalence of temporomandibular disorders in the Brazilian population: A systematic review and meta-analysis

This systematic review aimed to assess the prevalence of temporomandibular disorders (TMD) in the Brazilian population, with studies that used the RDC/TMD or DC/TMD as diagnostic tools. A total of 6365 people from 11 studies were included. Sample mean age ranged from 12 to 69.5 years. The pooled prevalence of TMD was 33.6% (95% CI 31.5-35.8; I2 = 37.2). Prevalence of TMD was higher in females (37.0%) than in males (29.3%). Our results indicate that TMD is a prevalent condition across Brazil's territories. The results from this meta-analysis can help calculate more accurate sample sizes for future studies.

Prevalence of Possible Sleep Bruxism and Its Association with Social and Orofacial Factors in Preschool Population

The prevalence of bruxism in the preschool population varies according to different investigations. The aim of this study was to investigate the prevalence of sleep bruxism and its relationship with social and orofacial factors in children aged 3 to 5 years. Three hundred forty-three preschool children were divided into two groups, one with nocturnal bruxism, as reported by parents, and another without this disorder. Questionnaires were distributed to the parents to determine the children's family social status and parafunctional habits at the time of the study. The clinical inspection confirmed the presence of certain parafunctional habits and the children's occlusal characteristics. The data obtained were analysed using descriptive statistics such as frequency chi-square tests to identify the influence of qualitative variables. Of the total sample, 28.9% of preschoolers presented sleep bruxism. The highest prevalence was observed in boys (61.6%) at the age of 5 years (41.4%). Characteristics associated with this pathology were lip incompetence, open bite, crossbite, and overbite, with p < 0.05. Sleep bruxism in preschool children has a higher prevalence in boys and is more frequently expressed from 5 years of age. Open bite, overbite, and crossbite should be considered factors associated with parafunction.

Exercise therapy improves pain and mouth opening in temporomandibular disorders: A systematic review with meta-analysis

OBJECTIVE

To analyse the effectiveness of exercise therapy in improving pain and active or passive maximum mouth opening in patients with temporomandibular disorders.

DATA SOURCES

PubMed Medline, Web of Science, Scopus, CINAHL Complete and Physiotherapy Evidence Database, until April 2022, in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

REVIEW METHODS

We included randomized controlled trials evaluating the effect of exercise therapy on pain and on active and passive maximum mouth opening in patients with temporomandibular disorders. Effect size was calculated using Cohen's standardized mean difference (SMD) and their 95% confidence interval (95% CI) in a random-effects model.

RESULTS

A total of 16 studies with 812 participants were included. Exercise therapy is effective in reducing pain (SMD: -0.58; 95% CI: -1.01 to -0.12) and increasing the pain pressure threshold (SMD: 0.45; 95% CI: 0.14-0.76), active and passive maximum mouth opening (SMD: 0.43; 95% CI: 0.14-0.71 and SMD: 0.4; 95% CI: 0.06-0.75, respectively). Subgroup analyses showed more effect of exercise therapy more splints versus splints on pain (SMD: -0.5; 95% CI: -0.73 to -0.26), active and passive maximum mouth opening (SMD: 1.14; 95% CI: 0.22-2.07 and SMD: 0.56; 95% CI: 0.06-1.06, respectively). On pain pressure threshold, exercise therapy was better than physiotherapy approach (manual therapy and electrotherapy) (SMD: 0.48; 95% CI: 0.09-0.87).

CONCLUSIONS

Therapeutic exercise is an effective therapy to reduce pain and increase pain pressure threshold and active and passive maximum mouth opening in patients with temporomandibular disorders.

Association between depression and temporomandibular dysfunction in adults - a systematic review

OBJECTIVE

To critically evaluate the literature and answer the question: "Is there an association between depression and temporomandibular disorder (TMD) in adults?"

METHODS

The personalized search strategy was applied to PubMed, Embase, Web of Science, and Scopus databases. Articles were selected in two stages according to the eligibility criteria. The Joanna Briggs Institute (JBI) tool was used to analyze the risk of bias according to the type of study.

RESULTS

The included articles presented a moderate risk of bias. Based on the studies, individuals with TMD have higher levels of depression compared to the control group. There is also a direct association in that individuals with depression are more susceptible to developing TMD.

CONCLUSION

There is a probable association between depression and TMD in adults. However, more studies with high methodological quality are needed to confirm this finding.

Temporomandibular Disorders as a Risk Factor for Suicidal Behavior: A Systematic Review

BACKGROUND

Temporomandibular disorders (TMD) are a group of common musculoskeletal dysfunctions that affect the temporomandibular joint or masticatory muscles and related structures or are expressed as a clinical combination of these two factors. The etiology of TMD is multifactorial and features related to anxiety, depression and mental disorders can contribute to the predisposition, onset and progression of TMD. The ability to adapt and develop coping attitudes was reduced in patients presenting with chronic pain, while suicidal behavior (suicidal ideation, suicide attempts, and suicide completion) was increased. The objective of this review was therefore to investigate suicidal behavior in relation to TMD.

METHODS

The review was performed according to the PRISMA 2020 guidelines. Six databases (PubMed, MEDLINE, EMBASE, Scopus, Ovid, and Google Scholar) were consulted through the use of keywords related to the review topic. The study is registered on PROSPERO (CRD42022320828).

RESULTS

The preliminary systematic search of the literature yielded 267 records. Excluding duplicates, 15 were considered potentially relevant and kept for title and abstract analysis. Only six articles were considered admissible reporting a single exposure factor, TMD and a single outcome, suicidal behavior, although these were evaluated through different assessment tools. We found a low association of TMD with suicidal behavior in observational studies, with estimates partly provided [prevalence ratio (PR) from 1.26 to 1.35, 95% confidence intervals (CI) from 1.15 to 1.19 (lower) and from 1.37 to 1.54 (higher); and odds ratios (OR) from 1.54 to 2.56, 95% CI from 1.014 to 1.157 (lower) and 2.051 to 6.484 (higher)], a relevant sample size (n = 44,645), but a few studies included (n = 6).

CONCLUSIONS

The results of the included studies showed that the prevalence data of suicidal behavior were more present in young adults with TMD, with a controversial association with gender. Suicidal behavior was also correlated and aggravated by the intensity of pain.

Association between Sleep Disorders and Sleep Quality in Patients with Temporomandibular Joint Osteoarthritis: A Systematic Review

Background: Osteoarthritis (OA) is a leading cause of disability, the most common form of chronic disease in the temporomandibular joint (TMJ), and the most severe disease type of temporomandibular disorders (TMD). The etiology of TMD is multifactorial, considering parafunctional habits, sleep bruxism, or sleep disturbance as common factors. Insomnia and apnea are the two most frequent forms of sleep disorders in TMD patients. Due to this, the objective of this systematic review was to highlight whether there is currently scientific evidence in the literature describing that patients with temporomandibular joint osteoarthritis (TMJ-OA) are associated with increased sleep disorders or impaired sleep quality. Methods: This systematic review was completed in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) statement and was registered with PROSPERO prior to completion of the main search. Original observational studies that analyze the association of sleep disorders and sleep quality in patients with TMJ-OA were included in the present review. Results: 770 studies were screened by abstract and title according to inclusion and exclusion criteria, and finally, 7 articles were included in the qualitative synthesis and a total of 772 patients diagnosed with TMJ-OA. Conclusions: There is insufficient evidence to indicate that patients with TMJ OA are associated with increased sleep disorders or poorer sleep quality.

Characteristics of patients with temporomandibular joint idiopathic condylar resorption

OBJECTIVE

To investigate characteristics of temporomandibular joint (TMJ) idiopathic condylar resorption (ICR) and analyze the related factors.

METHODS

A total of 755 consecutive patients (150 with ICR and 605 with anterior disc displacement [ADD]) from July 2015 to December 2018 were recruited. A comprehensive questionnaire characterizing the multidimensional impact of the TMJ was designed. Clinical examination and radiological evaluation were also performed. The odds ratio for each variable in the ICR group versus the ADD group was computed using logistic regression analysis.

RESULTS

Multivariate logistic regression analysis showed significant correlations between mouth opening restriction, disease course, mandibular retrusion, mandibular retrusion progression, skeletal Class II profile, and overjet in ICR patients.

CONCLUSION

These results suggest that a longer ADD disease course might have a strong relationship with ICR.

Clinical Manifestations, Imaging Features, and Pathogenic/Prognostic Risk Factors for Temporomandibular Disorders (TMD): A Case-Control Study Based on Psychogenic Factors of Patients

Objective. To survey the clinical manifestations and imaging features of temporomandibular disorders (TMD) and analyze the risk factors for pathogenesis/prognosis through a case-control study based on psychogenic factors of patients. Methods. According to the inclusion criteria, 200 adult patients were randomly enrolled from the maxillofacial department of our hospital from January 2020 to May 2021, including 100 patients with TMD as the study group and 100 healthy patients as the control group. The study group can be assigned into four subgroups according to their clinical manifestations: (1) articular area or/and masticatory muscle pain group, (2) mandibular movement abnormality group, (3) joint murmur group, and (4) two or more symptom groups. Based on the study of psychogenic factors of patients, the clinical manifestations and imaging features of TMD were determined, and the risk factors for pathogenesis/prognosis were analyzed. Results. The distribution of psychological status in the TMD group was higher than that in the control group ( $P<0.05$ ). The distribution of anxiety, depression, and somatic symptoms in the TMD group was significantly different from that in the control group ( $P<0.05$ ). Anxiety, depression, and somatic symptoms were the risk factors for TMD. Compared with the control group, the incidence of abnormal MRI images in patients with temporomandibular disorders was significantly different ( $P<0.05$ ). There were significant differences in psychological status (anxiety, depression, and somatic symptoms) among the three groups ( $P<0.05$ ). Anxiety, depression, and somatic symptoms were the risk factors for abnormal mandibular movement and joint tremor and murmur ( $P<0.05$ ). Somatic symptoms were the risk factors for various clinical symptoms of TMD ( $P<0.05$ ). Depression was the risk factor for pain ( $P<0.05$ ). Conclusion. In patients with TMD, MRI can early identify disc abnormalities and other related imaging features, which is helpful for more comprehensive clinical evaluation and treatment of TMD patients. There exhibits no significant difference in psychological status (anxiety, depression, and somatic symptoms) of patients with different clinical symptoms, and abnormal psychological status may be one of the risk factors leading to different clinical symptoms and development of different types of TMD patients.

Otoneurological assessment and quality of life of individuals with complaints of dizziness and temporomandibular disorders: a case-control study

OBJECTIVES

To evaluate the impact of temporomandibular disorders on the quality of life of patients with dizziness.

METHODS

An observational, case-control study evaluated 60 individuals with dizziness (20 cases and 40 controls), who were matched for gender and age. The individuals underwent to anamnesis, overall physical and otoneurological examination, tonal and vocal audiometry and impedanciometry, video head impulse test and the dizziness handicap inventory questionnaire.

RESULTS

The otoscopy was normal for all patients. There was an association between the presence of temporomandibular disorders and aural fullness (p < 0.01) and otalgia (p < 0.01). Audiometry was normal in 90% of the patients in the case group, with a significant association between temporomandibular disorders and normal audiometry (p < 0.01). The video head impulse test findings were normal in 66% of the patients in the case group and 45% of the control group, and there was no association between having temporomandibular disorders and vestibular alterations at the video head impulse test (p = 0.12). There were significant differences in total dizziness handicap inventory and in the functional and emotional domains (p < 0.01), with higher scores in the control group.

CONCLUSION

Aural fullness and otalgia symptoms are associated with temporomandibular disorders in patients with dizziness, and there is an association between normal complementary audiological tests and temporomandibular disorders. Vestibular alterations are not associated with temporomandibular disorders. However, patients with dizziness and without temporomandibular disorders showed greater quality of life impairment.

LEVEL OF EVIDENCE: 3

Original case-control study.

Psychometric Evaluation of the Krogh-Poulsen Test for the Diagnosis of the Temporomandibular Disorders

The Krogh-Poulsen Test is a classic instrument to measure dysfunction of the stomatognathic system whose psychometric properties are unknown. This study aimed to evaluate the psychometric properties of the Krogh-Poulsen Test for the diagnosis of temporomandibular disorders (TMDs). A cross-sectional study was designed, including 119 patients (63 patients with TMD and 56 healthy controls). Factorial validity, inter-rater reliability, error of measurement, diagnostic validity of the Krogh-Poulsen Test, and concurrent validity were analyzed. The Krogh-Poulsen Test showed a three-factor structure. The inter-rater agreement could be considered very good with a kappa index of 0.87 (95% CI 0.83-0.90) and Standard Error of Measurement of 0.79. Correlations were strong with other orofacial instruments, moderate with instruments measuring TMD-related disorders such as neck pain, headache, or dizziness, and poor with generic quality of life instruments. The Area Under the Curve ROC was 0.928 showing, for a cut-off point >1, a sensitivity of 90.48 (95% CI 80.4-96.4) and a specificity of 85.71 (95% CI 73.8-93.6) for the diagnosis of TMD disorders. The Krogh-Poulsen Test showed a three-factor structure, very good inter-rater reliability, a strong correlation with other orofacial instruments, and an excellent capacity to discriminate between patients with or without TMD.

Temporomandibular disorders in patients with polysomnographic diagnosis of sleep bruxism: a case-control study

BACKGROUND

Temporomandibular disorders (TMD) is a collective term that refers to complaints of temporomandibular joint (TMJ) pain, fatigue and/or pain of the craniocervical muscles, limitation of movement of the mandible, and TMJ noises. Sleep bruxism (SB) is a disorder involving rhythmic (phasic) or non-rhythmic (tonic) masticatory muscle activity during sleep and is not a movement disorder or a sleep disorder in otherwise healthy individuals. The present study aimed to support or reject the null hypothesis that there is no association between SB and TMD.

METHODS

The study population was recruited from patients who visited the Artmedica Clinic, Mossoro city, Rio Grande do Norte, Brazil. Patients who underwent polysomnography received information about the research and were invited to participate following the inclusion and exclusion criteria. The study sample consisted of 40 individuals with age ranging from 19 to 76 years. The subjects were administered the questionnaire of the European Academy of Craniomandibular Disorders (AEDC). Those who answered affirmatively to at least one question of the questionnaire were recommended to visit the primary researcher's dental clinic for examination; those who met the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) were evaluated, and their condition was classified into one or more subtypes of TMD. The subjects were divided into 4 groups according to the polysomnographic findings and the responses to the AEDC questionnaire. Of the 40 individuals who answered the AEDC questionnaire and underwent polysomnography, 28 presented with TMD symptoms. The data were expressed as simple frequency and percentage values using statistical software. Values of p < 0.05 were considered to be significant.

RESULTS

The results showed that the frequency of TMD in individuals diagnosed to have SB was 46.4%. According to the DC/TMD of the 28 individuals, the most prevalent TMD subtype was local myalgia (85.7%). Of the total subjects, 32.5% had TMD and SB, 36.4% were males, and in the age range of 31 to 40 years (40%).

CONCLUSION

In this study sample, there was no association between SB as currently defined and TMD, thus confirming previous findings on this topic.

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.

Ear symptoms in patients with orofacial pain and dysfunction - An explorative study on different TMD symptoms, occlusion and habits

Objectives

Ear symptoms coincident with TMD symptoms have been noticed for a long time. The aim was to investigate the relationship between reported ear symptoms in TMD patients and different TMD symptoms, dental occlusion, oral parafunction and habits.

Material and methods

Consecutive patients, ≥18 years of age and referred to a specialist clinic for orofacial pain and dysfunction during a three‐month period, were considered for the study. Patients with poor general or psychiatric health were excluded. One hundred thirty‐two patients were included and studied with regard to reported ear symptoms in relation to clinical dysfunction, occlusion, habits and subjective rating of their symptoms. A clinical examination was performed according to RDC/TMD and extended with occlusal factors, parafunctions and habits.

Results

Ear symptoms were reported by 72% of the TMD patients, with ear fullness in 49% as the most frequent symptom. The patients with ear symptoms were significantly older and proportionally more often females. Ear symptoms were significantly correlated to the subjective index, to myalgia (p = 0.003), decreased opening capacity (p = 0.01), TMJ pain (p = 0.02), parafunctions (p = 0.007), and some occlusal factor (p = 0.018–0.003). Muscle pain on palpation was significantly associated with ear fullness, and changed hearing and sensitivity to sound, on the same side (p < 0.005).

Conclusions

Ear symptoms are frequently reported by TMD patients. Concomitant ear symptoms are associated with oral parafunction and muscle pain on palpation on the same side as the ear symptoms.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Audiological Evaluation of Patients With Somatosensory Tinnitus Attributed to Temporomandibular Disorders

Purpose Tinnitus and temporomandibular disorders have already been associated in the literature, but despite many studies, it is still an intriguing discussion point. This study aimed to evaluate the prevalence of hearing loss among somatosensory tinnitus patients with temporomandibular disorders and to assess the influence of tinnitus on patients' quality of life. Method An otolaryngologist examined 585 patients in order to detect and evaluate the presence of tinnitus. Subjects were evaluated using the Portuguese version of the Research Diagnostic Criteria for Temporomandibular Disorders. An analysis of the somatic component of tinnitus was performed. Tinnitus was rated according to its onset (at least 6 months) and intensity with a visual analog scale. The sample was composed of 100 patients with somatosensory tinnitus divided into two groups: Group 1 (with temporomandibular disorder, n = 85) and Group 2 (without temporomandibular disorder, n = 15). The audiological evaluation was composed of pure-tone audiometry, high-frequency audiometry, tympanometry, and transient-evoked otoacoustic emissions. The impact of tinnitus on quality of life was assessed by the Tinnitus Handicap Inventory adapted and validated to Portuguese language. Results Pure-tone audiometry did not differ with statistical significance between groups (p = .29), neither did the high-frequency audiometry results (p = .74). Tinnitus Handicap Inventory scores also did not show any differences between Groups 1 and 2 (p = .67). Conclusions Subjects with somatosensory tinnitus, who also have temporomandibular disorders, do not seem to have hearing impairment. Also, they do not have a higher quality of life handicap when compared to those without tinnitus and temporomandibular disorder.

Efficacy of topical interventions for temporomandibular disorders compared to placebo or control therapy: a systematic review with meta-analysis

This systematic review focused on the efficacy of topical products in reducing temporomandibular joint disorder (TMD)-associated pain, in comparison to placebo or control interventions. The EMBASE, Web of Science, Cochrane Library, and MEDLINE via PubMed databases were searched for randomized controlled trials (RCTs) using topical interventions in adults diagnosed with TMD. The pain intensity was the primary outcome, and other clinical findings were the secondary outcomes. The risk of bias was evaluated according to the Cochrane's handbook. The search up to February 7, 2020 identified a total of 496 unduplicated references. Nine RCTs with 355 adult patients diagnosed with TMD were included. The meta-analysis did not show a significant reduction in baseline pain intensity in the nonsteroidal anti-inflammatory drug (NSAIDs) group, when compared to the placebo group (P = 0.288). One study demonstrated a statistically significant pain score decrease for Theraflex-TMJ compared to placebo after 10 d of treatment (P = 0.003) and follow-up, 5 d after the last application (P = 0.027). Ping On reduced pain at 4 weeks of application (P < 0.001) but not after 7 d of application (P = 0.136). In one study, cannabidiol (CBD) significantly improved the pain intensity compared to placebo (P < 0.001). However, no differences were found with capsaicin in the two studies (P = 0.465). Evidence was of low quality because the studies were considered as having an unclear or a high risk of bias and a small number of studies were analyzed. The evidence is not sufficient to support the use of topical NSAIDs and capsaicin, and limited evidence was found for Threraflex-TMJ, bee venom, Ping On, and CBD, with only one study reporting for each. Additional studies are recommended to validate these results.

Temporomandibular disorders in ankylosing spondylitis: a cross-sectional, monocentric study

There are contradictory results in the relevant literature about the relationship between objective determinants of craniocervical posture and temporomandibular disorder (TMD), whereas no study has worked on ankylosing spondylitis (AS) and TMD relationship. We conducted this study to test the predictors of TMD in AS patients and its relationship with craniocervical posture. AS patients aged between 18 and 50 years consecutively admitted to our outpatient clinics were recruited. TMD was diagnosed by 'Diagnostic Criteria for Temporomandibular Disorders (DC/TMD)'. Spinal mobility was assessed by BASMI; disease activity by ASDAS-CRP and neck disability by Neck Disability Index. Craniocervical posture was assessed on lateral cervical X-ray by measuring the craniocervical angle, cervical curvature angle, suboccipital distance, atlas-axis distance, and anterior translation distance. A total of 98 (58.2% female) patients with a mean age of 37.4 ± 8.2 years were enrolled in this study. TMD was diagnosed in 58 (59.2%) patients. Spinal mobility and craniocervical posture measurements were similar among the two groups. Smoking, bruxism (in females), neck disability and AS disease activity (in males) were higher in TMD patients. Multivariate analysis revealed active smoking (aOR 6.9; 95% CI 1.8-25.6; p = 0.004), bruxism in females (aOR 17.9; 95% CI 2.0-159.2; p = 0.01), high ASDAS in males (aOR 11.8; 95% CI 1.2-122.5; p = 0.038) and neck disability (aOR 12.7; 95% CI 3.8-42.9; p < 0.001) as independent risk factors for TMD in AS patients. No relationship between the craniocervical posture measurements and TMD was found in AS patients. Active smoking, high disease activity in males, bruxism in females and neck disability were found as predictors of TMD in AS patients.

Cervical spine range of motion, posture and electromyographic activity of masticatory muscles in temporomandibular disorders

Abstract Introduction: Temporomandibular joint disorders (TMD or TMJD) involve clinical problems and symptoms affecting the temporomandibular joint (TMJ) and associated structures. The temporomandibular joints are anatomically connected to the cervical region, where cervical spine movements occur simultaneously to masticatory muscle activation and jaw movements. Objective: Our study sought to assess the relationship between the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD), surface electromyography (sEMG) of the masticatory muscles, posture and cervical flexibility in women with TMD. Method: Fifty women with an average age of 27.0 ± 6.37 years, diagnosed with TMD according to RDC/TMD, were assessed for craniocervical posture, cervical flexibility and sEMG of the masticatory muscles. Results: There were no differences in jaw function limitations, depression, pain level and its interference in work ability and daily activities, posture and sEMG between TMD diagnoses or between muscle classification (p > 0.05). Depression scores were higher among participants with biarticular dysfunction (p = 0.023). The group with bruxism exhibited a higher pain level at assessment (p = 0.001) and a greater reduction in work ability (p = 0.039). Subjects with muscular and mixed TMD showed less cervical rotation to the right when compared with those with articular TMD. Conclusion: There was no difference in posture or sEMG values for TMD diagnoses, joint and muscle dysfunctions and the presence of bruxism. Muscle dysfunction is associated with reduced cervical rotation to the right. Jaw function limitations did not interfere in posture or sEMG and depression was associated with pain.

Prevalence of otological symptoms and parafunctional habits in patients with temporomandibular dysfunction

ABSTRACT Objective: to verify the relationship between otological symptoms and parafunctional habits in individuals with temporomandibular joint dysfunction. Methods: evaluations were based on the clinical records of 768 patients treated at a temporomandibular joint diagnostic center from 2010 to 2016. The inclusion criteria were completely filled out charts of adult patients (> 18 years of age) and the final sample comprised 516 clinical records. The presence/absence of parafunctional habits and otological symptoms (tinnitus, hearing impairment, dizziness, the sensation of plugged ears and imbalance) was recorded. Results: statistically significant associations were found between otological symptoms and both sex and the presence of parafunctional habits, as otological symptoms were more prevalent among women and individuals with at least one parafunctional habit. Conclusion: in the present sample, otological symptoms were positively associated with parafunctional habits in individuals with temporomandibular joint dysfunction.