Chronic Temporomandibular Disorders Research Articles

Construction of the chronic temporomandibular disorder patients: the association between neural and psychological pathways.

Chronic temporomandibular disorder (cTMD) as a term based on the diagnostic criteria for temporomandibular disorders (DC/TMD) classification refers, in this paper, to the condition listed that has a non-mechanical association without any obvious organic cause. Specifically, this is the condition that falls under the International Classification of Diseases 11th revision (ICD-11) classification of chronic primary and chronic secondary pains. This implies that there is increased responsiveness of nociceptive neurons in the central nervous system, a phenomenon known as central sensitisation. cTMD patients may have their beginning with genetic susceptibility to pain. Although no single gene is exclusively linked to cTMD, various genes associated with nervous and musculoskeletal systems are believed to play a role. Environmental triggers and epigenetic changes are also thought to contribute to cTMD development. The biopsychosocial model emphasises the need to comprehensively address biological, psychological and social factors in cTMD assessment and management. In this study, we leverage the cyclic causation framework within the biopsychosocial model to illuminate the intricate interplay between biological and psychosocial factors in the context of cTMD. The conceptualisation of cTMD involves the dynamic evolution of genetic predispositions, influenced by life events and other biological susceptibilities. These factors collectively contribute to the emergence of nociplastic changes, ultimately manifesting as the distinctive features observed in individuals afflicted with cTMD.

Minimum clinically important difference and substantial clinical benefit in patients with chronic temporomandibular disorders.

Research on temporomandibular disorder (TMD) responsiveness is scarce and limited regarding patients' representativeness. This study aimed to estimate minimum clinically important difference (MCID) and substantial clinical benefit (SCB) among a large and diverse patient population regarding sex and age. In this study, 162 patients participated from five hospitals. MCID and SCB in pain, functional disability and quality of life were examined with anchor-based methods. Patients' global impression of change was used as the anchor. Area under the curve (AUC) values were determined for testing accuracy. Changes from baseline and coefficient of variation by responsiveness status were calculated to explain the results of accuracy. SCB was estimated to be 2.18 for the numeric rating scale (NRS) for pain (AUC: 0.80 [95% CI: 0.72-0.88]) in all patients and 2.50 in women (AUC: 0.81 [95% CI: 0.71-0.89]). The estimated SCB of NRS for discomfort (1.50) and Jaw Functional Limitation Scale for mastication (1.35) had wide CIs for AUCs. Likewise, the estimated MCIDs of NRS for pain (0.80) and NRS for discomfort (1.50) had wide CIs for AUCs. Among non-responders who did not achieve the MCID of NRS for pain, the coefficient of variation was very high for all outcomes other than the NRS for pain. This study investigated the responsiveness of patients with TMD using a large and diverse patient sample. SCB in pain decrease can be used to assess the responsiveness of patients with TMD. Composite outcomes should be developed to estimate MCID.

Effectiveness and safety of hominis placental pharmacopuncture for chronic temporomandibular disorder: A multi-center randomized controlled trial

BackgroundHominis placental (HPP) extract has been approved by the Ministry of Food and Drug Safety in Korea for treating chronic liver diseases and postmenopausal syndrome. However, its efficacy and safety for treating chronic temporomandibular disorder (TMD) remains unclear. We aimed to assess the effectiveness and safety of HPP for treating chronic TMD compared with physical therapy (PT). MethodsThis study is a 2-arm parallel, multi-center, randomized controlled trial. We enrolled 82 chronic TMD patients from 2 Korean medicine hospitals between December 2019 and January 2021. We included patients with chronic TMD and randomly assigned them to undergo HPP or PT. The primary outcome was the difference in the scores for temporomandibular joint (TMJ) pain at baseline and week 6. The secondary outcomes were the scores for TMJ pain and bothersomeness, TMJ range of motion, the Korean version of Beck's depression index-Ⅱ, jaw functional limitation scale (JFLS) score, patient global impression of change (PGIC) scores, EuroQoL 5-dimension 5-level score, and short form-12 health survey (SF-12) scores. ResultsCompared with PT, HPP showed significantly superior effects on TMJ pain and bothersomeness, protrusive movement pain, JFLS (verbal, emotional, and global), SF-12, and PGIC scores at week 6 (P < 0.05). Compared with the PT group, the HPP group showed a significantly higher recovery rate (≥50 % reduction in the scores for TMJ pain at the 24-week follow-up). ConclusionHPP was more effective than PT managing pain and improving function and quality of life. Our findings demonstrate the effectiveness and safety of HPP for TMD treatment. Trial registrationThis study has been registered at clinicalTrials.gov (NCT04087005), Clinical Research Information Service (CRIS) (KCT0004437), and Ministry of Food and Drug Safety (No. 31886).

How do the mindfulness and sensory-behavioural-emotional aspects influence the painful experience related to temporomandibular disorder?

Chronic pain is persistent or recurrent pain lasting longer than 3 months. The experience of temporomandibular disorder (TMD)-related pain is modulated by emotional and social factors, with mindfulness encapsulating these aspects. To investigate the association between cognitive-behavioural-emotional characteristics, mindfulness and the painful experience in women with chronic pain-related TMD. A cross-sectional study was conducted, including 90 women aged between 18 and 61 years old, diagnosed with chronic pain-related TMD according to the Diagnostic Criteria for Temporomandibular Disorder, considering both temporomandibular joint and muscle pain. Specific instruments were employed to assess cognitive-behavioural-emotional aspects. The Mindful Attention Awareness Scale and the Five Facets of Mindfulness Questionnaire scales evaluated the level and construct of mindfulness. The relationship between variables was analysed using bivariate association tests (.05 > p < .20), followed by multiple regression tests (p < .05). The heightened experience of pain correlated with increasing age, a low level of education, the attribution of the locus of control by chance, and lower levels of mindfulness (p < .05). The heightened experience of pain was negatively influenced by mindfulness levels (p < .05). On the other hand, the painful experience was mainly influenced by facets describing negative formulation, distraction, non-reactivity and non-judgement (p < .05). Demographic, cognitive-behavioural-emotional data and levels of mindfulness and its facets presented different influence weights on the painful experience. These findings provide support for future studies focusing on mindfulness strategies, education and pain management in women with chronic pain-related TMD.

Age distribution of East Asian TMD patients and age-related differences in DC/TMD axis I findings.

The pattern of age distribution in East Asian temporomandibular disorder (TMD) patients and age-related differences in DC/TMD diagnostic subtypes/categories were evaluated. TMD patients from two University-based centers in China and South Korea were enrolled. Axis I physical diagnoses were rendered according to DC/TMD. Patients were categorized into six age groups (15-24, 25-34, 35-44, 45-54, 55-64, and 65-84 years; Groups A-F respectively). Youths/young adults (Groups A-C) formed 74.1% of TMD patients. TMJ disc displacements (74.9%), arthralgia (49.2%), and degenerative joint disease [DJD] (36.8%) were the most common TMD subtypes. The majority had combined (54.0%) and chronic (58.5%) TMDs. Youths/young adults and middle-aged/old adults had substantially lower frequencies of merely pain-related (6.2-14.5%) and intra-articular (13.8-16.8%) TMDs correspondingly. "Being female" increased the prospects of pain-related/combined TMDs by 96%/49%, respectively. East Asian TMD patients comprised mostly of youths/young adults who had an alarmingly high prevalence of TMJ DJD.

Chronic temporomandibular disorder pain patients with a history of neuropathic pain treatment: a narrative research on their diagnosis and treatment history

The aims of this qualitative research were (1) to gain more insight in the diagnostic and treatment history of patients with chronic temporomandibular disorder (TMD) pain; (2) to get a deeper understanding of possible factors that are involved in the possible delay in setting a TMD-pain diagnosis and receiving appropriate treatment; and (3) to get a deeper understanding of the perspectives and experiences of chronic TMD-pain patients on the possible improvement of various aspects of their diagnostic and treatment journey.MethodsIn this narrative research, semi-structured interviews took place with patients who experienced chronic orofacial pain (OFP) for at least three years before getting diagnosed with, and treated for, TMD pain by an OFP specialist in an interprofessional setting.ResultsIn total, ten patients were interviewed in-depth. Patients experienced their chronic OFP in different ways, but all reported a significant impact of their pain on their quality of life. All patients visited numerous health care professionals before their TMD diagnosis was set. Among others, they underwent anti-neuropathic pain medication therapies and invasive surgeries, which did not significantly reduce their chronic OFP. The interprofessional TMD-pain treatment reduced the suffering of the chronic OFP substantially, also 6 months after the start of therapy, and improved the quality of life for all patients. In most of them, the OFP intensity was also decreased.ConclusionChronic TMD-pain patients with a history of neuropathic pain treatment may experience a long journey until receiving the appropriate diagnosis and treatment. This stresses the need to improve the implementation of chronic TMD-pain guidelines.

Effectiveness of an 8-week neck exercise training on pain, jaw function, and oral health-related quality of life in women with chronic temporomandibular disorders: a randomized controlled trial

To test the effectiveness of an 8-week exercise program targeted to the neck muscles compared to manual therapy, and placebo treatments on orofacial pain intensity, jaw function, oral health-related quality of life (OHRQoL), and jaw range of motion (ROM) in women with Temporomandibular Disorders (TMD). In this randomized controlled trial, fifty-four women (between 18–45 years old) with a diagnosis of myofascial or mixed TMD according to the Research Diagnostic Criteria for TMD (RDC/TMD) were randomized into three groups: Neck motor control training (NTG), Manual Therapy Group (MTG), and Placebo Group (PG). All patients were evaluated with the Visual Analog Scale, Mandibular Function Impairment Questionnaire, Oral Health Impact Profile-14, and jaw Range of Motion (ROM) at baseline, immediately after treatment (after 8 weeks of treatment), one month, and three-month follow-up. For all outcomes, a mixed analysis of variance (ANOVA) with repeated measures was conducted with a Bonferroni post hoc test. NTG was significantly better than the PG group on pain and jaw function at the end of treatment, one- and three-month follow-up (Effect Size (ES) &gt;0.7). For OHRQoL, NTG was significantly better than MTG and PG at the end of treatment and at three-month follow-up (ES &gt;0.7). The results of this project are encouraging, and they could be used to guide clinical practice in this field. Exercises targeted to the neck (which require low therapeutic supervision) could be a simple and conservative way to improve pain and disability for women with TMD with neck involvement.

Management of chronic pain secondary to temporomandibular disorders: a systematic review and network meta-analysis of randomised trials

ObjectiveWe explored the comparative effectiveness of available therapies for chronic pain associated with temporomandibular disorders (TMD).DesignSystematic review and network meta-analysis of randomised clinical trials (RCTs).Data sourcesMEDLINE, EMBASE, CINAHL, CENTRAL, and...

Whole-genome methylation profiling reveals regions associated with painful temporomandibular disorders and active recovery processes.

Temporomandibular disorders (TMDs), collectively representing one of the most common chronic pain conditions, have a substantial genetic component, but genetic variation alone has not fully explained the heritability of TMD risk. Reasoning that the unexplained heritability may be because of DNA methylation, an epigenetic phenomenon, we measured genome-wide DNA methylation using the Illumina MethylationEPIC platform with blood samples from participants in the Orofacial Pain: Prospective Evaluation and Risk Assessment (OPPERA) study. Associations with chronic TMD used methylation data from 496 chronic painful TMD cases and 452 TMD-free controls. Changes in methylation between enrollment and a 6-month follow-up visit were determined for a separate sample of 62 people with recent-onset painful TMD. More than 750,000 individual CpG sites were examined for association with chronic painful TMD. Six differentially methylated regions were significantly ( P < 5 × 10 -8 ) associated with chronic painful TMD, including loci near genes involved in the regulation of inflammatory and neuronal response. A majority of loci were similarly differentially methylated in acute TMD consistent with observed transience or persistence of symptoms at follow-up. Functional characterization of the identified regions found relationships between methylation at these loci and nearby genetic variation contributing to chronic painful TMD and with gene expression of proximal genes. These findings reveal epigenetic contributions to chronic painful TMD through methylation of the genes FMOD , PM20D1 , ZNF718 , ZFP57 , and RNF39 , following the development of acute painful TMD. Epigenetic regulation of these genes likely contributes to the trajectory of transcriptional events in affected tissues leading to resolution or chronicity of pain.

Investigating the effect of obsessive-compulsive disorder on clinical symptoms of temporomandibular joint disorders.

Temporomandibular disorders (TMD) are a group of clinical conditions involving muscles of mastication, temporomandibular joint (TMJ), and related structures or both. TMD is characterized by facial pain in TMJ and muscles of mastication, limitation or deviation of jaw movement, and TMJ sounds during jaw movement and function. The highest risk of TMD prevalence is between 18 and 24 years, and a relationship is between chronic TMD and psychological disorders such as stress and depression. The knowledge of the function of this joint and those with TMD symptoms when visiting the dentist will help to provide an ideal treatment plan for the patient. Therefore, if the therapist is familiar with the various etiological factors of this disorder, he will provide better treatment, especially if the simultaneous effect of psychological factors such as stress and obsessive-compulsive disorder (OCD) along with occlusal factors such as posterior cross-bite, overjet, and overbite is measured, it can be a valuable guide for clinicians. In this study, 385 patients were examined by DASS42 and Maudsley's test and classified into normal, with stress, and stress plus OCD groups. TMJ was examined for each of them by the TMD-RDC test. The presence or absence of TMD was noted in their file. The prevalence of TMD was 20.7% in the normal group, 30.70% in the stress group, and 44.68% in the stress and OCD group. After analyzing the data by SPSS 24 and performing analysis of variance and Duncan tests, no significant difference was found between the probability of TMD in normal and stressed groups, but the stress and OCD group has a higher chance of TMD. Although the co-occurrence of stress and OCD is associated with the prevalence of TMD, it cannot be considered a cause of TMD.

Knowledge and Awareness of Temporomandibular Disorders (TMDs) among Post-graduate residents

INTRODUCTION: Malocclusion and TMD were believed to have a correlation when it is associated that the alteration of form might cause alteration in the stomatognathic system function. A multidisciplinary approach is particularly important for the successful treatment of chronic TMD cases. Management of TMD involves the work of dentists from various specialities. It is multifactorial in nature and requires proper examination and treatment planning. Thus, the primary purpose of this study is to find out the awareness of TMDs among postgraduate students. MATERIALS AND METHODOLOGY: The present study was retrospective in nature. A questionnaire involving TMDs was sent to all postgraduates involved in patient treatment through google forms. All participants were asked to anonymously answer the structured questionnaire containing multiple-choice and open-text questions in google forms. The questionnaire was specially developed for students and was organized into three sections. RESULTS: 204 participants responded and returned the completed questionnaires. Results showed that 98 % of the respondent’s occlusal disturbance causes TMD and TMJ problems are associated with malocclusion. The majority of the participants were aware of the aetiology and diagnosis but only 53% of them were aware of the treatment protocols. CONCLUSION: The causes and diagnosis domains of the questionnaire yielded a high degree of agreement while the treatment modalities were not known. Most of them were not aware of the treatment modalities reason being a lack of knowledge during the course of their undergraduate and postgraduate study.

Is low back pain a risk/prognostic factor for the development and/or progression of temporomandibular disorders? A systematic review with meta-analysis.

To evaluate the association between low back pain (LBP) and painful temporomandibular disorders (TMDs). Systematic review of observational studies. Searches were conducted using OVID MEDLINE, CINHAL, Web of Science and PUBMED databases up to 21 October 2022. Qualitative and quantitative analyses were performed. Risk of bias (RoB) was assessed using the Quality in Prognosis Studies tool (QUIPS). Eight studies were included in the present review with meta-analysis. The first onset of TMDs was more likely in patients with previous chronic LBP (hazard ratio (HR) 1.53 [95% confidence interval (CI): 1.28; 1.83, p < .00001]). In addition, patients with chronic LBP had 3.25 times the odds (OR) [95% CI: 1.94; 5.43, p < .00001] of having chronic TMDs than those who did not have chronic LBP. In addition, the higher the exposure to chronic LBP, the higher the risk of developing a first onset of TMDs. Chronic LBP can be considered a risk/contributing factor for painful TMDs. Although there is a high certainty in the evidence linking chronic LBP with the risk of a first onset of TMDs, there are insufficient studies to draw definitive conclusions. Furthermore, while an association between chronic LBP and chronic TMDs and a dose-effect was observed between these two conditions, a limited number of studies and evidence exist to support these findings. Future studies are needed to increase the body of evidence.

O.3.2-8 Sedentary behaviour, physical activity, and sleep patterns of women with chronic temporomandibular disorders on days with and without pain: a cross-sectional study

Abstract Purpose Sedentary behaviour (SED) and low level of physical activity (PA) might be associated with the development or worsening of pain. Still, studies assessing physical behaviours by accelerometry in individuals with orofacial pain are limited. This study aims to assess whether women with temporomandibular disorders (TMD) present different patterns of physical behaviours in days with (DWP) or without pain (DWoP). Methods Twenty-nine out of forty-four women (mean age 29.21 sd 7.96) were diagnosed with TMD and monitored over seven days using a thigh-worn accelerometer. DWP was determined when subjects presented pain in one of the craniocervical regions (head, jaw and neck) with intensity of at least 3 in the numerical rating scale. To be considered a DWoP, the individual presented less than 3 points in the three regions. Daily time-use compositions were described in terms of SED in short (&amp;lt;30 min) and long (≥30 min) bouts, light PA (LPA), moderate-to-vigorous PA (MVPA), and time-in-bed. Isometric log-ratios (ilr) were calculated to express the ratio of time-in-bed to time spent awake, SED relative to LPA and MVPA, SED in short relative to long bouts, and LPA relative to MVPA. Differences between DWP and DWoP were examined using MANOVA, followed by univariate post-hoc tests of pairwise differences. Results During DWP, women with TMD spent more time in SED in short (239 min) and long bouts (419 min), less time in LPA (245 min), MVPA (68 min), and in bed (468 min) compared with DWoP (235, 378, 263, 70 and 493 min, respectively). The MANOVA showed that all sets of ilrs did not differ statistically (ηp2 = 0.19, p = 0.25). Still, the post-hoc tests showed a trend that time spent SED relative to LPA and MVPA was larger in DWP than in DWoP (Cohen’s d = 0.36, p = 0.05). Conclusions Women with TMD did not show different patterns of physical behaviours in DWP or DWoP. However, there is a trend of more sedentary behaviour and less physical activity in DWP compared to DWoP. Future studies should consider other pain intensity cut-offs, isolated pain locations, and larger sample sizes to confirm these results.

Management of Pain Symptoms and Contractures in Patients with Chronic Temporomandibular Disorders and Psychosocial Comorbidities Using Gaalas Phototherapy

Abstract The most important clinical indicators of temporomandibular disorders (TMD) are pain in the temporomandibular joints, masticatory and cervical muscles, as well as a reduction in the opening capacity of the mouth. Psychosocial factors have a significant impact in the persistence of the disease and should be taken in consideration in the treatment plan. The aim of the present study was to perform clinical and statistical evaluation on the management of pain symptoms and overcome of pronounced arthro- and myogenic mandibular contractures in GAD 7 positive patients with chronic temporomandibular disorders using combined irradiation with infrared gallium-aluminum-arsenide laser (785 nm), superluminescent visible red (633 nm) and infrared (880 nm) light emitting devices. Materials and methods. The study included 62 individuals with various types of temporomandibular disorders, which were established using the latest diagnostic criteria – DC/TMD, 2014, revision 2020. Fifteen out of 62 patients responded positively to the GAD 7 questionnaire, which indicates depression and/or anxiety. In 8 out of these 15 cases, the presence of pain symptoms, mandibular contractures and psychosocial comorbidities exceeded 6 months. According to DC/TMD standards, these are patients with chronic temporomandibular disorders and they were the target group for our study. The average interincisal distance from this eight-member group was 27.62 mm (SD – 8.17). Results. The Student t-test for the dependent samples showed a significant reduction in VAS pain scores and an increased interincisal distance after phototherapy procedures. Conclusions. Combined phototherapy has proven to be an effective treatment of mandibular contractures, joint and muscle pain in TMD patients with psychosocial comorbid conditions.

An Update on Temporomandibular Disorders (TMDs) and Headache.

To provide an overview and highlight recent updates in temporomandibular disorders (TMDs) and their comorbidity with headache disorders regarding pathophysiology and management. In the last decade, there have been great advancements in the understanding of TMDs and their relationship with neurovascular pains such as headaches. Understanding of TMDs is necessary for the context of its comorbidity with primary headache disorders. The literature regarding management of these comorbidities is scarce but points to combination therapy including pharmacological and non-pharmacological approaches to optimize management. The use of CGRP receptor-targeted monoclonal antibodies or CGRP receptor antagonists should be explored for the management of chronic TMDs. It could also be used as a novel monotherapy or in combination with non-pharmacological approaches for TMDs' comorbidity with headache, particularly migraine. Research is needed to support evidence-based management protocols. A team involving neurology (headache medicine) and dentistry (orofacial pain) is critical for optimal management.

Awake and Sleep Oral Behaviours in Patients With Painful Temporomandibular Disorders

The aim of this research was to explore the oral behaviours exhibited by individuals with and without temporomandibular disorders (TMD) pain, and with various pain characteristics; and to determine which oral behaviour is correlated with painful TMD. 328 patients with TMD who visited Orofacial Pain Clinic were included in this retrospective cross-sectional study. The patients were categorised into 2 groups-painful TMD and non-painful TMD-based on pain status; their other pain characteristics were recorded. To evaluate oral behaviours, researchers utilised the Oral Behaviors Checklist (OBC) and categorised into 3 levels based on the Diagnostic criteria for TMD scoring manual. To investigate the associations amongst demographic information, oral behaviour levels, and TMD pain status and characteristics, logistic regression was employed, whilst t tests were used to analyse OBC scores. Logistic regression was also used to examine individual oral behaviours in relation to specific pain characteristics. Age and marital status were associated with TMD pain status. Significantly higher OBC scores were observed in chronic pain compared to acute pain group, but the scores were not significantly different for pain status and other pain characteristics. OBC score and level were associated solely with TMD pain chronicity. According to multivariate logistic regression, "clench or grind teeth when sleeping" was the strongest predictor of TMD pain and "place tongue forcibly against teeth" was the strongest predictor of chronic painful TMD. High oral behaviour level and OBC scores were associated with chronic painful TMD. Sleep bruxism was the strongest predictor of TMD pain. Age and marital status were correlated with TMD pain status. In the treatment of TMD, there can be potential benefits in addressing and managing oral parafunctional behaviours.

The Contribution of Insomnia and Obstructive Sleep Apnea on the Transition from Acute to Chronic Painful Temporomandibular Disorders and their Persistence: A Prospective 3-Month Cohort Study

ABSTRACT Background Insomnia, and Excessive Daytime Sleepiness (EDS), a surrogate marker of Obstructive Sleep Apnea (OSA), are common sleep-related conditions among painful temporomandibular disorders (TMD) patients. OSA was found to increase the risk of chronic painful TMD. Aims This prospective cohort study aims to determine the contribution of insomnia and EDS on acute to chronic painful TMD transition as well as its persistence when chronic pain is defined by: (i) duration (> 3 months), and (ii) dysfunction (Graded Chronic Pain Scale [GCPS II-IV]). Methods From 456 patients recruited between 2015 to 2021, through four locations in Canada, 378 completed the follow-up. A diagnosis was obtained using the Research Diagnostic Criteria or the Diagnostic Criteria for TMD. Insomnia was assessed with the Insomnia Severity Scale (ISS), and OSA was assessed using the Epworth Sleepiness Scale (ESS) which measures EDS, both at baseline. Patients completed the GCPS form at baseline and 3-month follow-up. Results Borderline associations were found between EDS and the transition or persistence of chronic painful TMD when chronic pain was defined by pain duration (RR adjusted_duration = 1.11, P = 0.07) and dysfunction (RRadjusted_dysfunction =1.40, P = 0.051). Furthermore, EDS was specifically associated with persistent painful TMD when chronic pain was defined by pain duration (RR = 1.13, 95%CI: 1.00-1.26, P = 0.04). Insomnia was not related to the study outcomes (RRadjusted_duration = 0.94, P = 0.27, RRadjusted_dysfunction =1.00, P = 0.99). Conclusion Results indicate that EDS contrary to insomnia predicted the persistence of chronic painful TMD at a 3-month follow-up.

Evaluation of Plasma Calcitonin Gene-Related Peptide as a Biomarker for Painful Temporomandibular Disorder and Migraine.

To assess associations of plasma calcitonin gene-related peptide (CGRP) with chronic temporomandibular disorder (TMD) myalgia/arthralgia or frequent/chronic migraine, alone and in combination, and to evaluate relations between the CGRP concentration and clinical, psychological, and somatosensory characteristics of participants. The cross-sectional study selected four groups of adult volunteers: healthy controls (HCs), TMD without migraine, migraine without TMD, and TMD with migraine. Each group comprised 20 participants, providing 94% power to detect statistically significant associations with CGRP concentration for either TMD or migraine. TMD and headache were classified according to the Diagnostic Criteria for TMD and the International Classification for Headache Disorders, 3rd edition, respectively. Plasma CGRP was quantified with a validated high-sensitivity electrochemiluminescent Meso Scale Discovery assay. Questionnaires and clinical examinations were used to evaluate characteristics of TMD, headache, psychological distress, and pressure pain sensitivity. Univariate regression models quantified associations of the CGRP concentration with TMD, migraine, and their interaction. Univariate associations of the CGRP concentration with clinical, psychological, and pressure pain characteristics were also assessed. Among 80 participants enrolled, neither TMD nor migraine was associated with plasma CGRP concentration (P = 0.761 and P = 0.972, respectively). The CGRP concentration (mean ± SD) was similar in all 4 groups: HCs 2.0 ± 0.7 pg/mL, TMD 2.1 ± 0.8 pg/mL, migraine 2.1 ± 0.9 pg/mL, and TMD with migraine 2.2 ± 0.7 pg/mL. CGRP concentration was positively associated with age (P = 0.034) and marginally with body mass index (P = 0.080) but was unrelated to other participant characteristics. In this well-powered study, interictal plasma concentration of CGRP was a poor biomarker for TMD and migraine.

Remodeling dental anatomy vs sham therapy for chronic temporomandibular disorders. A placebo-controlled randomized clinical trial

BackgroundEvidence regarding the etiology or effective treatments for chronic orofacial pain, the majority diagnosed as temporomandibular disorder (TMD), is limited. PurposeTo investigate whether occlusal equilibration therapy (ET) and decreasing the (higher) angle of the lateral guidance on the nonworking-side leads to a reduction in chronic TMDs intensity. MethodsIt was conducted a randomized, explanatory, single blind with blinded assessment, placebo-controlled trial with strong protection against bias involving patients with chronic TMDs. Participants were randomly assigned to receive equilibration therapy or sham therapy. ET in this study consisted of minimal invasive occlusal remodeling to obtain balanced occlusion with reduction of the steeper angle of lateral mandibular movement with respect to the Frankfort plane. The primary outcome was a change in the pain intensity score (on a 0–10 point scale, with 0 indicating no pain and 10 the worst possible pain) at month 6. Secondary outcomes include maximum unassisted mouth opening and psychological distress. ResultsA total of 77 participants underwent randomization, 39 of whom received ET and 38 sham therapy. The trial was stopped early for efficacy, according to preestablished rules when 67 participants (n = 34, n = 33, respectively) had completed the analysis. At month 6, the mean unadjusted pain intensity score was 2.1 in the ET and 3.6 in the sham therapy group (adjusted mean difference, −1.54; 95% confidence interval [CI] −0.5 to −2.6; P = 0.004; ANCOVA model). The mean increase in maximum unassisted mouth opening (main secondary outcome) was significantly higher in the real therapy group (adjusted mean difference 3.1 mm, 95% CI 0.5–5.7, p = 0.02). ConclusionET significantly reduced the intensity of facial pain associated with chronic TMDs and increased maximum unassisted mouth opening, as compared with sham therapy, over the course of 6 months. There were no serious adverse events.Funded by the Instituto de Salud Carlos III from the Ministry of Science and Innovation of the Government of Spain and European Regional Development Fund, Grant nº PI11/02507; “una manera de hacer Europa”.

Pressure release technique versus placebo applied to cervical and masticatory muscles in patients with chronic painful myofascial temporomandibular disorder: A randomised clinical trial.

The therapeutic approach to myofascial TMD should focus on pain relief and rehabilitation of function. This study investigated whether pressure release technique (PRT) is effective for reducing pain in people with chronic myofascial temporomandibular disorders (TMD). A single-blinded randomised parallel-group trial, with 3 months follow-up was conducted. A total of 72 patients were randomly allocated to receive PRT or sham PRT. Primary outcome was pain assessed with a visual analogue scale (VAS). Secondary outcomes included pressure pain thresholds (PPTs), range of opening of the mouth (ROM), Neck Disability Index (NDI), Pain Catastrophizing Scale (PCS), Tampa Scale for Kinesiophobia (TSK-11), State-Trait Anxiety Index (STAI) and State-Trait Depression Index (ST-DEP). All parameters were assessed at baseline, at the end of the treatment and at 3 months follow-up. Statistical analysis was performed by ANOVA. There were significant main effects of time, group and interaction between time and group (F ≥ 21.92; p < .001) on VAS pain. Post hoc tests showed a significant reduction in VAS pain scores in the PRT group (≥31.9%; p < .001). Effect sizes were moderate in the PRT group at all follow-up periods (≥1.25 Cohen's d). Also, there were significant effects of time in secondary outcomes (F ≥ 9.65; p < .001), and there were also interactions between time and group (F ≥ 3.82; p < .002) with better effects in the PRT group. The inclusion of PRT to conventional management with occlusal splints and self-care management appears to be effective to improve self-reported levels of pain in patients with chronic myofascial TMD pain. Retrospectively registered (ClinicalTrials.gov: NCT03619889).