To Temporomandibular Disorders Research Articles

Effects of botulinum toxin type A in patients with painful temporomandibular joint disorders: a systematic review and meta-analysis.

To assess the therapeutic efficacy of botulinum toxin type A (BTX-A) for managing myofascial pain related to temporomandibular disorders (TMDs). This study was conducted according to the PRISMA 2020 statement guidelines. The PubMed, Embase, and Cochrane Library databases were searched. Only randomized controlled trials were included. The primary outcome was a pain score on the visual analog scale, and the secondary outcomes were maximum mouth opening and adverse effects. The Cochrane risk of bias tool was used to assess risk bias. A meta-analysis of studies with the same interventions, controls, assessment methods, and follow-up durations was performed. A total of 519 studies were retrieved, of which 20 randomized controlled trials were included in the qualitative analysis and six were included in the meta-analysis. The results showed that, compared with placebo, BTX-A injection was more effective at relieving myofascial pain, and its effect was similar to that of conventional methods. However, there was no difference in maximum mouth opening between the two groups. After the study assessment with the RoB 2.0 tool, six studies showed a low risk of bias, 13 studies showed some concerns regarding the reported results, and only one study showed a high risk of bias. Adverse effects of BTX-A injection were observed in four studies. In conclusion, BTX-A is effective at relieving pain in TMD patients but does not improve mouth opening. To minimize adverse effects, we recommend a low dose of BTX-A for TMD patients who do not experience complete pain relief from conservative treatments.

Risk factors associated with symptoms of temporomandibular disorders among women with hypermobile Ehlers-Danlos syndrome: Questionnaire-based study in Finland and Sweden.

Generalized joint hypermobility as a characteristic feature of Ehlers-Danlos syndromes (EDS) is among the factors contributing to temporomandibular disorders (TMD). To evaluate the prevalence of TMD symptoms and their risk factors among women born in Sweden or Finland who were 27- to 78-year-olds with diagnosed hypermobile EDS (hEDS). A cohort of women with confirmed hEDS (n = 185) was constructed from the members of the National EDS Associations in both countries. Based on questionnaire data, frequency of independent variables in terms of socio-demographic, general health and oral health-related factors, comorbid symptoms and psychological distress for self-reported TMD symptoms as the dependent variables, were calculated first. Prevalence ratios (PR) and their 95% confidence interval (95% CI) were estimated for the association between independent and dependent variables. Nearly all participants reported TMD symptoms (98%) with TMD pain (95%), TMJ clicking (90%) and jaw fatigue (80%) as the most common symptoms and TMJ crepitation (63%) and luxation (44%) as the least common symptoms. Risk factors for TMD among 27- to 50-year-olds participants were Finland as a country of birth, living alone and self-reported worst pain in the body (not the joints). The respective risk factors among the 51- to 78-year-olds were Finland as a country of birth, family history of EDS, tinnitus and regularly taking contraceptives. Among adult women with confirmed hEDS, socio-demographic and health-related factors and comorbid symptoms were significantly associated with TMD but with differences regarding age group. Therefore, management of TMD requires a multidisciplinary approach among the affected.

A multidisciplinary approach to temporomandibular disorders (TMD): The role of physical therapy

A multidisciplinary approach to temporomandibular disorders (TMD): The role of physical therapy

Associations between oral behaviors, temporomandibular disorder subtypes and psychological distress in adult women: a retrospective case-control study

Oral behaviors and psychological distress are known to be related to temporomandibular disorders (TMDs). However, the relationship between various oral behaviors and specific TMD subgroups in adult women experiencing psychological distress is still unclear. To investigate the relationship between various oral behaviors and different TMD subgroups with different psychological distress states. A total of 210 female TMD patients were divided into 3 subgroups according to their symptoms: pain-related (PT), intra-articular (IT) and combined pain-related and intra-articular (CT). Another 70 participants without TMDs were recruited as the non-TMD (NT) control group. We used reduced Chinese versions of the Oral Behavior Checklist (OBC-Ch 8), including awake (OBC-Ch 6) and sleep-related activities, the 9-item Patient Health Questionnaire (PHQ-9) and the 7-item Generalized Anxiety Disorder Scale (GAD-7) to assess oral behaviors and psychological distress. Differences in OBC scores among TMD subgroups were analyzed using Chi-square, Kruskal-Wallis H and post hoc tests, with significance set at p < 0.05. Oral behavior subscale scores significantly differed among TMD subgroups (p < 0.01). The OBC-Ch 8 scores of PT, IT and CT subjects were significantly higher than the NT group. PT and CT groups also had significantly higher GAD-7 and PHQ-9 scores. Sleep-related OBC scores of the PT, IT and CT groups were higher than those in the NT group, regardless of psychological states (p < 0.001). In psychologically distressed subjects, OBC-Ch 8 scores for PT and CT subgroups were significantly higher than those in the NT group. Oral behaviors are differentially associated with various TMD subgroups in female adults, and a correlation exists between individual psychological status and OBC scores.

Biomechanical behavior of customized splint for the patient with temporomandibular disorders: A three-dimensional finite element analysis

The mechanical overloading of temporomandibular joint (TMJ) is generally linked to temporomandibular disorders (TMD). However, in patients with a typical combination of maxillofacial morphology and occlusal features, the reduction of joint load and treatment with general occlusal splints are often ineffective. This study investigates the biomechanical behavior of the stomatognathic system in a TMD patient with personalized splints by finite element analysis. The therapeutic position, determined based on the intercuspal position, served as the basis for designing personalized customized splints. The design of occlusal contact and splint structure was evaluated in terms of their impact on the maximum stress level in the TMJ and the biting forces on the dentition. The relationship between joint stress and biting force was further examined during treatment with different customized splints. In preoperative case, there was a significant increase in stress level and stress concentration in the medial to posterior band of the articular disc. However, in all customized splint cases, the highest stress area shifted to the intermediate zone and exhibited a decrease. Notably, the bi-splints demonstrated superior ability in relieving overloading and balancing the occlusal force on both sides of the dentition, as verified by clinical treatment. The predictable simulated results offer valuable interactive information regarding TMJ overload, aiding doctors in making better-informed clinical decisions in future.

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

Bruxism is defined as a repetitive jaw-muscle activity characterised by clenching or grinding of the teeth and/or by bracing or thrusting of the mandible. Bruxism can occur during sleep (sleep bruxism, SB) or during wakefulness (awake bruxism, AB). To date, the effect of AB on the purported negative consequences of bruxism has remained unclear. The assessment of AB, its relation to temporomandibular disorders (TMD) treatment modalities, and their possible outcomes were investigated among TMD patients resistant to treatment in primary care and referred to a tertiary care clinic. The records of 115 patients were studied. Patients were referred to the Head and Neck Centre, Department of Oral and Maxillofacial Diseases, Helsinki University Central Hospital, for TMD treatment between 2017 and 2020. The data derived from the eligible patients' records included the following: background data (age and sex), referral data (reason and previous treatment), medical background (somatic and psychiatric), clinical and possible radiological diagnoses at a tertiary care clinic, treatment modalities for masticatory muscle myalgia, bruxism assessment, its possible treatment modalities and their outcomes, and overall management outcome. We analysed the outcomes of single treatment modalities and combined groups of modalities. For the demographic data, the Chi-squared test and Fischer's Exact test were used to determine the associations between the categorical variables. A Sankey-diagram was used to describe the flow of treatment. Temporomandibular joint-pain-dysfunction syndrome (K07.60) was the most frequent single reason to refer a patient to tertiary care (17.4%). At referral, men had myalgia (M79.1) significantly more often (p = .034) than women. Similarly, men had depression (p = .002) more often and other psychiatric diagnoses (p = .034). At tertiary care, the presence of AB was assessed in 53.9%, and self-reported AB was recorded in 48.7%. In patients with possible AB, those who were prescribed neuropathic pain medication showed significantly less improvement in symptoms (p = .021) than those who underwent splint therapy (p = .009). Overall, half of the patients showed overall improvement in their TMD symptoms from the treatment combinations. Despite several treatment modalities, only half of the patients showed improvement in their symptoms in the present study. A standardised assessment method encompassing all factors contributing to bruxism behaviours and their consequences is suggested.

Prevalence of signs and symptoms related to temporomandibular disorders and orofacial pain in patients indicated for orthognathic surgery: a meta-analysis.

To evaluate the prevalence of signs and symptoms related to temporomandibular disorders (TMD) and orofacial pain in patients with indication for orthognathic surgery. The search was carried out in seven electronic databases and gray literature. Studies that evaluated the frequency of signs and symptoms related to TMD and orofacial pain were included. The risk of bias was assessed using the Joanna Briggs Critical Appraisal tool. A meta-analysis of proportions with a random effect model was performed and the GRADE tool judged the certainty of evidence. After searching the databases, 1859 references were retrieved, 18 of which were selected for synthesis. The prevalence of individuals with at least one TMD symptom was 51% [CI95% = 44-58%], and 44% of the subjects had temporomandibular joint click/crepitus [CI95% = 37-52%]. Additionally, 28% exhibited symptoms related to muscle disorders [CI95% = 22-35%], 34% had disc displacement with or without reduction [CI95% = 25-44%], and 24% had inflammatory joint disorders [CI95% = 13-36%]. The prevalence of headache was 26% [CI95% = 8-51%]. The certainty of evidence was considered very low. Approximately 1 in 2 patients with dentofacial deformity presents some sign and symptom related to TMD. Myofascial pain and headache may be present in approximately a quarter of patients with dentofacial deformity. A multidisciplinary treatment is necessary for these patients, involving a professional with expertise in the management of TMD.

Major clinical approaches of prefabricated and customized prostheses for the temporomandibular joint: a systematic review

Introduction: The temporomandibular joint (TMJ) is composed of dense fibrocartilage formed between the mandibular condyle and the temporal bone. The high collagen content of this disc provides great rigidity and durability. Osteoarthritis-like degenerative joint disease belonging to temporomandibular disorder (TMD) is a destruction of bone and cartilage with a consequent inflammation that enhances tissue destruction. As a treatment, the implantation of a total alloplastic TMJ prosthesis is an innovative approach to the treatment of TMD. There are two types of prefabricated (stock) and custom computer-aided design/computer-aided manufacturing (CAD/CAM) systems. Objective: The present study aimed to carry out a concise systematic review of the major clinical approaches of prefabricated and customized prostheses for the temporomandibular joint. Methods: The systematic review rules of the PRISMA Platform were followed. The search was carried out from February to May 2023 in the Scopus, PubMed, Science Direct, Scielo, and Google Scholar databases, using articles from 2018 to 2023. Results and Conclusion: A total of 107 articles were found, 34 articles were evaluated and 19 were included and developed in this systematic review study. Considering the Cochrane tool for risk of bias, the overall assessment resulted in 21 studies with a high risk of bias and 15 studies that did not meet GRADE. It was concluded that the clinical results of the stock and CAD/CAM prostheses suggested major improvements in mouth opening and reduced pain as a result of the rehabilitation of temporomandibular joint function. The results showed comparable data for the two types of prosthesis design at 6 months postoperatively. Thus, both temporomandibular joint and custom implants work well despite the additional advantages of custom prostheses, along with increasing access to digital technology, which may result in custom devices dominating the market in total temporomandibular joint replacement systems.

Abdominal Acupuncture for Non-Responding TMD Patients: a Retrospective Observational Study in General Practice

Pain related to Temporomandibular Disorders (TMD) is severe, negatively affecting patients' quality of life, and often resistant to conventional treatments. Abdominal Acupuncture (AA) is known to be particularly effective for pain, especially chronic and musculoskeletal pain, but it is still poorly studied and never investigated in TMD patients. To analyze the efficacy of AA for the treatment of patients with subacute and chronic pain related to TMD and non-responding to previous conventional therapies (occlusal splint, medications, physical therapy). Twenty-eight patients, 24 F and four M (mean age 49.36 years), were recruited from January 2019-February 2021. All patients underwent AA treatment: two sessions per week for four weeks, for a total of eight sessions. At the beginning of therapy (T0) and at the end of the cycle (T1) the following data were evaluated: maximum mouth opening (MMO); cranio-facial pain related to TMD (verbal numeric scale, VNS); pain interference with normal activities and quality of life of patients (Brief Pain Inventory, BPI); oral functioning (Oral Behavior Checklist, OBC); impression of treatment effectiveness (Patients' Global Impression of Improvement, PGI-I Scale). Statistical comparison of data before and after the AA treatment was performed by Wilcoxon's signed-rank test (significance level p < 0.05). The MMO values were significantly improved after one cycle of AA (p = 0.0002). In addition, TMD-related pain had a statistically significant decline following AA treatment (all p < 0.001). Patients' general activity and quality of life (BPI) were described as improved following a course of AA, with statistically significant values for all aspects considered (all p < 0.05). Abdominal acupuncture resulted in effective treatment of subacute/chronic-resistant pain related to TMD, capable of improving mandibular function and facial pain, and reduced the interference of pain affecting patients' quality of life.

Clinical and imaginological characterization of synovial chondromatosis in the temporomandibular joint: A systematic review

Introduction: Synovial Chondromatosis (SC) is a metaplastic rheumatologic condition that manifests itself in the Temporomandibular Joints (TMJs). This causes common symptoms related to Temporomandibular Disorders (TMD). Differential diagnosis is obtained through clinical and imaging evaluation. Objective: To clarify, through a systematic review, the manifestations that characterize, differentiate and relate SC in the TMJ from the point of view of clinical and imaging diagnosis. Material and methods: The PubMed database and the keywords were used: Synovial Chondromatosis, Clinical Diagnosis, Imaging Tests, TMD Patient, Healthy Patients, Signs and Symptoms. Inclusion criteria were: five years, English language, title covering the keywords and clinical and original research in humans, literature reviews and case reports. As exclusion criteria: cases that did not deal with SC in the ATM, articles that do not match the objective of the work. The characteristiSC, differences and relationships between TMD and SC were the main variables analyzed. Results: Initially, 335 articles were found, after application of filters, inclusion criteria and evaluation of abstracts, nine were selected. Five relevant publications were added. The signs and symptoms common to the alterations: localized joint pain, edema, limitation of mouth opening and joint noises. Magnetic resonance images, computed tomography and TMJ radiographs were fundamental for the differential diagnosis and indicated the presence of intraarticular fibrocartilaginous bodies in the SC. Conclusion: It is necessary to interpret the imaging tests in order to establish the differential diagnosis between TMD and SC.

Temporomandibular disorders-related videos on YouTube are unreliable sources of medical information: A cross-sectional analysis of quality and content.

The amount of online medical information available is rapidly growing and YouTube is considered as the most popular source of healthcare information nowadays. However, no study has been conducted to comprehensively evaluate YouTube videos related to temporomandibular disorders (TMD). So this study aimed to evaluate the content and quality of YouTube videos as a source of medical information on TMD. A total of 237 YouTube videos that were systematically searched using five keywords (temporomandibular disorders, tmd, temporomandibular joint, tmj, and jaw joint) were included. Included videos were categorized by purpose and source for analysis. The quality (DISCERN, Health on the Net (HON), Ensuring Quality Information for Patients (EQIP), and Global Quality Scale (GQS)) and scientific accuracy of video contents were evaluated. Total content, DISCERN, HON, EQIP, and GQS scores were 7.5%, 38.9%, 35.2%, 53.0%, and 48.6% of the maximum possible score, respectively. Only 69 videos (29.1%) were considered as "useful" for patients. News media, physician, and medical source videos showed higher evaluation scores than others. Quality evaluation scores were not significantly correlated or negatively correlated with public preference indices. In the ROC curve analysis, content and DISCERN score showed above excellent discrimination ability for high-quality videos based on GQS (P < 0.001) and total score (P < 0.001). YouTube videos related to TMD contained low quality and scientifically inaccurate information that could negatively influence patients with TMD.

EFFECTS OF MYOFASCIAL RELEASE IN TEMPOROMANDIBULAR DYSFUNCTION

The temporomandibular joint (TMJ), associated with factors that cause dental disharmony, such as wrong bites and stress, can affect the joint and progress to temporomandibular disorder (TMD). The objective was to evaluate the effects of manual techniques of myofascial release (LM) of the face and neck muscles in the quality of life and in the psychological conditions, during the beginning and end of the treatment. Participated in the study 15 participants, aged between 18 and 55 years, with signs and symptoms of TMD. The treatment consisted of LM associated with stretching and pomping techniques cervical, as well as health education. There was a significant reduction in the pain domain values and a significant increase in the SF-36 total score, indicating an improvement in quality of life. Regarding HADS, there were no significant changes.

Temporal changes and gender differences related to orofacial symptoms in two cohorts of 75-year-old Swedish subjects examined in 2007 and 2017: A repeated cross-sectional study.

To compare two cohorts of 75-year-old persons, born 10 years apart, in regard to reported symptoms related to temporomandibular disorders (TMD) and orofacial complaints with special reference to gender differences. In 2007, a questionnaire comprising questions on social factors, general and oral health, and a series of attitude-related questions was mailed to all individuals born in 1932 living in two Swedish counties (N = 5195), and in 2017 to all born in 1942 (N = 7204). The response rate for the cohort examined in 2007 was 71.9% (n = 3735) and 70.7% (n = 5091) for the cohort examined in 2017. Bivariate statistical analyses were applied. Reported bruxism and pain from the temporomandibular joint were significantly higher in the 1942 cohort compared to the 1932 cohort, while reports of oral lesions and daytime dry mouth were lower. Women reported problems significantly more frequently in most of the domains investigated in both 2007 and 2017, that is,TMD, burning mouth, sensitive teeth, oral lesions, taste changes, daytime/night-time dry mouth, except bad breath. TMD-related symptoms increased while complaints from oral lesions and daytime mouth dryness decreased between 2007 and 2017. Temporal changes were otherwise few, but the findings underline the gender inequalities that exist, to the disadvantage of women. This must be considered when planning for clinical care/dental education to appropriately address the needs of older people.

A Comparative Evaluation of Malocclusion and Associated Risk Factors in Patients Suffering with Temporomandibular Disorders: A Systematic Review and Meta-analysis of Observational Studies

AbstractAn association of malocclusion as potent risk factor to temporomandibular disorders (TMDs) has been under question since ages. A systematic review and meta-analysis of case–control and cohort studies was performed following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses)guidelines to compare the prevalence of TMDs in subjects with malocclusion to patients with normocclusion. The study was registered on the PROSPERO database (identifier: CRD42022315863). An elaborate electronic database (PubMed, DOAJ, and Google Scholar) and manual search resulted in 325 articles, among which 7 and 3 articles were shortlisted for qualitative and quantitative review, respectively, for articles published from January 2000 until December 2021. A total of 4,183 participants were included in this review with age range of 5 to 75 years. New–Castle Ottawa tool was employed for quality assessment, while I 2 statistical value for meta-analysis was interpreted in accordance with the Cochrane Handbook for Systematic Reviews of Interventions. Fixed effect model was applied as, I 2 = 0. Pooled odds ratio with 95% confidence interval for all three studies was 14.64 [4.43, 48.36] suggesting that TMDs were 14.64 times more associated in patients with malocclusion (cases) than patients without malocclusion (controls). Within the limitations and fair quality of evidence of the current review and analysis, TMDs and associated symptoms are more prevalent in patients with malocclusion with or without more associated factors.

Prevalence of sagittal molar and canine relationships, asymmetries and midline shift in relation to temporomandibular disorders (TMD) in a Finnish adult population

Objective To examine the prevalence of sagittal relationships, asymmetries and midline shift, and their associations with temporomandibular disorders (TMD) in the Northern Finland Birth Cohort 1966 (NFBC1966). Materials and methods 1845 subjects participated in a clinical examination at the age of 46. Occlusal measurements were performed using 3D models. Symptoms of TMD were screened using validated questions, and signs and diagnoses of TMD were assessed using a modified protocol of the Diagnostic Criteria for TMD (DC/TMD) and questionnaires. Associations between variables of occlusion and TMD were evaluated with χ 2-test and Fisher's exact test and using logistic regression analyses, adjusted for self-reported general health, mental health, bruxism, and rheumatoid arthritis. Results The most common sagittal relationships were Class I and normal canine relationship. Half-cusp Class II and post-normal canine relationship were more frequent in females, and Class III and pre-normal canine relationship in males. Deviations from normal cuspid or molar relationships showed a weak but statistically significant association with TMD, especially in females. Half-cusp Class II and Class II relationships were more frequent in relation to joint-related TMD signs and diagnoses while missing canines were associated with pain-related TMD diagnoses. Conclusions The present study findings gave some indications that canine relationships are associated with pain-related TMD, whereas Angle II sagittal occlusal relations may associate with joint-related TMD. Occlusal characteristics should therefore be taken into account as one possible associating factor in subjects with TMD.

Influência do autocuidado utilizando as práticas integrativas e complementares durante a pandemia da COVID-19 em crianças e adolescentes de 4 a 13 anos com bruxismo e disfunção temporomandibular

Bruxism is a behavior of the mandibular muscles, characterized by clenching and/or dental grinding, both in wakefulness and in sleep, which can lead to Temporomandibular Disorders (TMD). Highly prevalent in children and possessing a multifactorial etiology, psychosocial aspects stand out, especially stress and anxiety. The need for social distancing during the COVID-19 pandemic has had consequences for children and has given rise to new formats of actions in Dentistry. This study evaluated the influence of self-care on the manifestations of Bruxism/TMD in children who were undergoing treatment, before the pandemic, Care Center for children with Bruxism and TMD, whose acronyms in Portuguese is SABDI, located in Ribeirão Preto School of Dentistry (FORP-USP), through assisted interventions, implemented remotely, of Complementary and Integrative Therapies (CIT). Prior to the interventions (T0), the parents answered the questionnaire (Q1) about the child (in Google Forms, sent by WhatsApp and e-mail). The proposed practices were explained in virtual meetings (Google Meet) and performed for 21 days and recorded in a “Control Diary”. A new questionnaire (Q2) was completed for comparative analysis after the interventions (T1). Of the 37 children who were undergoing treatment, the final sample of 18 who completed all the proposed steps showed a quantitative difference in the items: “pain in the mouth/face when chewing”; “pain or difficulty opening and closing the mouth”; “waking up with pain in the face or headache” and “headache during the day or night”; “grinding teeth while awake”; “frequency grinding teeth while awake”; “grinding teeth while sleeping”; “frequency grinding teeth while sleeping”; “restless sleep”; “nightmare”; and “insomnia”. Evidence of statistical difference was observed with a P value &lt;0.05, in the item “clenches teeth while awake” (p=0.0057). It is concluded that the proposed interventions influenced the manifestations of Bruxism, favoring its control.

Relationship of bruxism with oral health-related quality of life and facial muscle pain in dentate individuals.

BackgroundTo determine whether there is a correlation of bruxism (sleep, daytime, or both) with oral health-related quality of life and facial pain of muscular origin in dentate individuals. Material and MethodsSeventy-four dentate patients (complete dentition) were included in this study. These individuals had pain in the facial muscles due to temporomandibular disorder (TMD). Smokers; and those with obstructive sleep apnea, TMD of joint origin associated or not with pain, malocclusion, and cancer; and users of illicit drugs, psychiatric medications, and alcohol were excluded. Obstructive sleep apnea, bruxism (of sleep and/or daytime), facial muscle pain, and oral health-related quality of life were assessed by the following questionnaires: Berlin Questionnaire, Pintado et al. questionnaire, VAS (Visual Analog Scale) facial muscle pain questionnaire, and Oral Health Impact Profile – 14. Four groups were created: 1) no bruxism; 2) sleep bruxism; 3) daytime bruxism; and 4) sleep and daytime bruxism. Spearman’s correlation test was applied to verify if there was a correlation between the collected data. P values less than 0.05 were considered statistically significant. ResultsThere was a positive correlation of daytime bruxism with mean pain in the last 3 months (P<0.05) and the worst pain experienced in the last 3 months (P<0.05). ConclusionsBruxism (sleep, daytime, or both) showed a positive correlation with lower oral health-related quality of life (P<0.05). Key words:Bruxism, facial pain, temporomandibular joint disorders, surveys and questionnaires, health-related quality of life.

Is the Course of Headache Complaints Related to the Course of Orofacial Pain and Disability in Patients Treated for Temporomandibular Pain? An Observational Study

Migraine, tension-type headache (TTH) and headaches attributed to temporomandibular disorders (TMD) are prevalent in patients with TMD-pain. The objective was to describe the course of headache complaints as compared to the course of TMD complaints in TMD-pain patients with headache during usual care multidisciplinary treatment for TMD. This was a 12-week longitudinal observational study following adults with TMD-pain and headache during a usual-care multidisciplinary TMD-treatment. The Graded Chronic Pain Scale was used for both TMD and headache to measure pain-related disability (primary outcome measure), pain intensity, days with pain and days experiencing disability (secondary outcome measures). Stratified for the headache type, general linear modelling for repeated measures was used to analyze changes over time in the TMD complaints and the headache complaints. TMD-pain patients with migraine (n = 22) showed significant decrease of pain-related disability for both TMD and headache complaints over time. No difference in the effect over time was found between the two complaints. Patients with TMD-pain and TTH (n = 21) or headache attributed to TMD (n = 17) did not improve in disability over time. For the secondary outcome measures, the results were equivocal. In conclusion, TMD-pain patients with migraine, improvement in TMD-related disability was comparable to headache-related disability for TMD-pain patients with TTH or with headache attributed to TMD, no improvements in disability were found.

Association of temporomandibular disorders with pain sensitivity: A cohort study.

Pain related to temporomandibular disorders (TMD) can be linked with multiple site pain (MSP), and may associate with increased pain sensitivity, more frequently among women than men. The aim of the study was to examine the associations of pressure pain threshold (PPT) and tolerance (PPTo) with TMD and associated MSP in the Northern Finland Birth Cohort 1966 (NFBC1966) study. Altogether 1961 NFBC1966 subjects attended clinical medical and dental examination at the Institute of Dentistry, University of Oulu in 2012-2013. Clinical examinations were carried out using a modified Diagnostic Criteria for TMD protocol (DC/TMD). MSP was defined based on questions regarding body pain sites. Additionally, PPT and PPTo were assessed using algometer measurements. Mann-Whitney U-test and Tobit regression models were used to analyse associations between TMD sub-diagnoses, MSP, PPT and PPTo, stratified by sex. Further models were adjusted with anxiety and depressive symptoms, which were assessed using Hopkins Symptom Checklist-25 (HSCL-25) and two-way interaction terms. Among females, lower PPT and PPTo were associated with myalgia and arthralgia. Among males, lower PPT and PPTo were associated with MSP-linked TMD. Tobit regression analysis showed significantly lower PPT and PPTo values in the myalgia and arthralgia subgroups among female TMD subjects. Among females, disc displacement with reduction had an inverse association with PPT and PPTo. Among males, lower PPTo was associated with degenerative joint disease and MSP-linked TMD. The pain regulatory mechanisms behind TMD act differently between the genders as local TMD among females and MSP-linked TMD among males were associated with pain sensitivity. The study shows that there are differences in the associations of painful TMD with pressure pain tolerance, pressure pain sensitivity and MSP between male and female subjects.

Disturbed sleep may be a core risk factor for jaw functional limitation in patients with painful temporomandibular disorders.

Pain related to temporomandibular disorder (TMD) usually affects jaw function. In patients with TMD, little is known about the biopsychosocial relevance to jaw functional limitations. This study explored the impact of biopsychosocial risk factors on jaw functional limitation in patients with painful TMD. A comprehensive set of patient-reported outcomes (PROs), consisting of pain severity (Brief Pain Inventory), psychological stress (Symptom Checklist-90-Revised), catastrophising thought (Pain Catastrophizing Scale), kinesiophobia (Tampa Scale for Kinesiophobia-TMD), sleep quality (Pittsburgh Sleep Quality Index) and jaw functional limitation (Jaw Functional Limitation Scale-20), were administered, and clinical examinations were performed in patients with TMD. This study included the data obtained from 131 patients with painful TMD. In the logistic regression analysis, biomedical factors (age, sex, pain duration and TMD phenotype) were not associated with jaw functional limitation. Correlations were higher in the order of sleep quality (ρ=0.946), pain severity (ρ=0.582), pain catastrophising (ρ=0.535), kinesiophobia (ρ=0.486) and emotional distress (ρ=0.268). Multiple regression analysis demonstrated three predictors, including pain severity (p=.001), kinesiophobia (p=.023) and sleep quality (p<.001) for jaw functional limitation. In the mediation analysis, the indirect effect of pain severity on the association between sleep and limitation was significant (p<.0001). Jaw functional limitation is associated with biopsychosocial factors. In particular, sleep may be a core risk factor for functional limitation in patients with painful TMD.