Current thinking in the management of temporomandibular disorders in children: A narrative review.

The aim of this narrative review is to discuss current opinions on paediatric temporomandibular disorders (TMDs) due to their increasing incidence in routine secondary care maxillofacial clinics. A MEDLINE and EMBASE search was performed of the literature published in the past three years concerning paediatric TMD. Of 261 papers identified, 89 were selected for relevance, of which 52 full texts were eligible and 41 included. The narrative of this paper follows three domains: myogenous and arthogenous pain, juvenile idiopathic arthritis (JIA), and reconstruction. The principles of treating mild TMD in children are similar to those in adults, with even more emphasis on the management of psychosocial issues and self-care. The use of medication, however, needs to be more cautious. Symptomatic disc displacement should be treated to reduce inflammation, so early arthrocentesis or arthroscopy is relevant. Controversy exists on disc repositioning to reduce or even reverse condylar degeneration in the growing condyle. If undertaken it should ideally be performed arthroscopically by surgeons with significant experience. Arthritic disease is usually associated with JIA so a multidisciplinary approach is the focus of treatment. The role of arthroscopy in the management of symptoms is increasing but it does not prevent disease progression. Surgical correction may be required for secondary deformity. Reconstruction remains a challenge with no ideal autogenous method. Alloplastic joints are gaining popularity, but the long-term outcomes are unknown. Surgery can be undertaken with minimal morbidity, and the use of joint replacements, even as space maintainers, may therefore be more beneficial than repeated failed autogenous treatments.

Chronic Overlapping Pain Conditions in people with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): a sample from the Multi-site Clinical Assessment of ME/CFS (MCAM) study.

BACKGROUND: Chronic overlapping pain conditions (COPCs), pain-related conditions that frequently occur together, may occur in patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and could impact illness severity. This study aimed to identify comorbid COPCs in patients with ME/CFS and evaluate their impact on illness severity. METHODS: We used data from 923 participants in the Multi-Site Clinical Assessment of ME/CFS study, conducted in seven U.S. specialty clinics between 2012 and 2020, who completed the baseline assessment (595 ME/CFS and 328 healthy controls (HC)). COPCs included chronic low back pain (cLBP), chronic migraine/headache (cMHA), fibromyalgia (FM), interstitial cystitis/irritable bladder (IC/IB), irritable bowel syndrome (IBS), temporomandibular disorder (TMD). Illness severity was assessed through questionnaires measuring symptoms and functioning. Multivariate analysis of variance and analysis of covariance models were used for analyses. Log-binomial regression analyses were used to compute prevalence of COPCs and prevalence ratios (PR) between groups with 95% confidence intervals. Both unadjusted and adjusted results with age and sex are presented. RESULTS: 76% of participants with ME/CFS had at least one COPCs compared to 17.4% of HC. Among ME/CFS participants, cMHA was most prevalent (48.1%), followed by FM (45.0%), cLBP (33.1%), and IBS (31.6%). All individual COPCs, except TMD, were significantly more frequent in females than males. The unadjusted PR (ME/CFS compared to HC) was highest for FM [147.74 (95% confidence interval (CI) = 20.83-1047.75], followed by cLBP [39.45 (12.73-122.27)], and IC/IB [13.78 (1.88-101.24)]. The significance and order did not change after age and sex adjustment. The COPC comorbidities of cLBP and FM each had a significant impact on most health measures, particularly in pain attributes (Cohen's d effect size 0.8 or larger). While the impact of COPC comorbidities on non-pain attributes and quality of life measures was less pronounced than that on pain, statistically significant differences between ME/CFS participants with and without COPCs were still evident. CONCLUSIONS: More than 75% of ME/CFS participants had one or more COPCs. Multiple COPCs further exacerbated illness severity, especially among females with ME/CFS. Assessment and management of COPCs may help improve the health and quality of life for patients with ME/CFS.

Pain Catastrophizing and Functional Activation During Occlusion in TMD Patients-An Interventional Study.

In temporomandibular disorder (TMD), the effects of standard interventions such as using an occlusal splint and its impact on pain relief and pain catastrophizing are poorly understood. Earlier work pointed to a crucial role of insula activation with changes in pain relief by occlusal splint treatment. We performed a functional imaging study using specially developed splint systems to allow for a placebo-controlled longitudinal design. Using functional MRI we examined 20 TMD patients during repetitive occlusal movements at baseline and over the course of splint therapy and also collected self-reported pain catastrophizing. For balancing performance between baseline and after intervention we used occlusion force measures in an individualized fMRI-splint system. Splint therapy lasted for approximately 7 weeks with one group selected by randomization wearing a palatine placebo splint over the first 3 weeks (delayed start; 11 individuals). As expected, fMRI activation in areas involved in pain processing (insula, primary and secondary somatosensory cortex) decreased with intervention. At baseline a positive correlation between activation of the left anterior insula and pain catastrophizing was present. Both parameters decreased over intervention while associations were primarily observable for patients with rather mild TMD.

Impact of applying different levels of threshold-based artifact correction on the processing of heart rate variability data in individuals with temporomandibular disorder.

Although heart rate variability (HRV) is a valid method to evaluate the behavior of the autonomic nervous system in individuals with temporomandibular disorder (TMD), the measurement can easily be biased by factors involving the analysis methodology, such as the removal of artifacts. Therefore, the objective of this investigation is to evaluate the impact of using different levels of threshold-based artifact correction to process HRV data in individuals with TMD. This cross-sectional observational study. Adults aged 18 to 55 years old with a diagnosis of myogenic TMD, score ≥ 50 on the Fonseca Anamnestic Index (FAI) and pain ≥ 3 on the Numerical Pain Scale (NPS) participated. The HRV was registered in the supine position (short-term) using a Polar S810i. Kubios software was used for HRV analysis using all filters. One-way ANOVA with Tukey-Kramer post-hoc was used to test the differences in HRV using the different Kubios Software artifact correction filters. The effect size was calculated based on the Cohen d. The very strong filter was statistically different (p < 0.05) compared to the no filter in all overview and time domain variables. In the frequency domain, the variables VLF, LF, HF and Total Power showed statistical differences (p < 0.05) when using the very strong filter. The same occurred with the variables SD1, SD2 and DFA α2 of the non-linear analysis (p < 0.05). The most restrictive filter of the Kubios software (very strong) significantly impacts the quantification of HRV parameters in individuals with TMD.

A Comparative Analysis of Botulinum Toxin Use Versus Other Therapies for Temporomandibular Disorders: A Systematic Review.

Existing literature regarding the efficacy of Botulinum toxin A (BoNT-A) therapy in improving the clinical outcomes of temporomandibular disorders (TMDs) is ambiguous and lacks consistency. Thus, this study aimed to evaluate the efficacy of BoNT-A in reducing pain, occlusal force, electromyographic (EMG) changes, and maximum mouth opening compared with placebo and other interventions. An electronic database search was conducted using MEDLINE, PubMed, Google Scholar, the Cochrane Library, and ClinicalTrials.gov from January 2000 to June 2024 to identify randomized controlled trials (RCTs). A manual search complemented the electronic search. The Risk of Bias 2 (RoB 2) assessment was used to evaluate the internal validity of the included studies. A total of 1719 studies were identified, of which 23 fulfilled the inclusion criteria. Nineteen of these studies evaluated pain levels (primary outcome) after BoTN-A therapy, with six of them observing a decrease. In terms of secondary outcomes, seven of 10 studies noted an increase in maximum mouth opening, while all six reported a drop in EMG activity, and all four found a decrease in occlusal force following BoNT-A therapy. Muscle activity and biting force were significantly reduced in the therapeutic groups. Clinicians must consider these adverse events before treating patients with BoNT-A therapy. Additional regulatory guidelines and standardization of injection protocols are essential in improving therapeutic outcomes and patient safety. These findings suggest that BoNT-A may be a feasible option for TMD management but should be used with caution in clinical settings.

Comparative Evaluation and Correlation of Hyoid Bone Position, Airway Dimension, and Psychological Status in Class II Vertical and Horizontal Malocclusion Cases With Temporomandibular Disorder Compared to Class I Non-Temporomandibular Disorder Cases.

Introduction Temporomandibular disorder (TMD) involves discomfort and impaired function in the masticatory muscles and temporomandibular joint (TMJ), with a multifaceted etiology that includes biomechanical, neuromuscular, psychological, and biological factors. This research aims to assess and correlate the hyoid bone position, airway dimensions, and psychological status in class II Hz (horizontal) and Vt (vertical) malocclusion cases with TMD in contrast to non-TMD class I cases. Methodology This research was carried out at the Orthodontics Department, Sharad Pawar Dental College and Hospital, Sawangi, with consent obtained from the ethical committee. A total of 63 adult patients with class I, class II horizontal, and class II vertical malocclusions were selected. TMD was diagnosed using the Helkimo index, and patients were categorized accordingly. Psychological status was evaluated using the Warwick-Edinburgh scale, while the placement of hyoid bone and airway dimensions were assessed using lateral cephalograms. Statistical analysis involved descriptive and inferential statistics using SPSS version 27.0, with a significance level of p < 0.05. Results The research showed a noteworthy difference in the hyoid bone's location, airway dimensions, and psychological status among the three groups. Class II TMD patients (both vertical and horizontal) exhibited higher hyoid bone positions and larger Go-Hy-Me angles (angle formed by the gonion-hyoid line and the hyoid-menton line) compared to class I patients. In addition, class II vertical TMD patients showed the most reduced airway dimensions. Psychological assessments indicated higher stress, anxiety, and depression levels in class II TMD patients, particularly in the vertical group, compared to class I non-TMD patients. Conclusion This study highlights the intricate relationships between hyoid bone position, airway dimensions, and psychological status in TMD patients. TMD patients present with hyoid bones positioned closer to the cranium and mandible, larger Go-Hy-Me angles, and reduced airway dimensions. Psychological distress exacerbates TMD symptoms, negatively impacting overall well-being and quality of life. Orthodontists should consider these interrelated factors when devising treatment plans to improve patient outcomes. Future longitudinal studies with larger samples and advanced imaging techniques are recommended to further elucidate these interactions.

Ultrasonographic assessment of the lateral pterygoid muscle for BoNT-A injection.

The upper head of the lateral pterygoid muscle (LPM) is known to insert into the capsule of the temporomandibular joint and articular disc, and therefore its relationship with temporomandibular disorders (TMD) has been consistently suggested. The aim of the study was to determine the anatomical features of the LPM using ultrasonographic (US) imaging. Around 120 hemifaces from 60 healthy Korean volunteers were included in this study. US images were taken with the subject's mouth 2 cm open. The transducer was placed at a position where the infratemporal fossa could be observed through the mandibular notch, and its position was recorded. The locations of the coronoid process (CorP), lateral margin of the condylar process (ConP), and midpoint of CorP and ConP (MP) were measured with reference to the ala-tragus line. The thicknesses of the skin and subcutaneous tissue, the masseter muscle, the temporalis muscle, and the depth of the LPM were measured at the MP. The masseter muscle, temporalis muscle, and LPM were observed in all cases and located in order from superficial to deep. The MP was located 39.6 ± 3.3 mm anterior and 7.8 ± 1.6 mm inferior to the tragus. The thicknesses of the skin and subcutaneous tissue, the masseter muscle, the temporalis muscle, and the depth of the LPM at the MP were 9.7 ± 1.0, 10.3 ± 1.3, 10.9 ± 1.6, and 30.9 ± 1.9 mm, respectively. The information reported in this study may be useful for determining the location of the LPM and adjacent anatomical structures in TMD patients and provide accurate and safe injection guidelines.

3D printed versus milled stabilization splints for the management of bruxism and temporomandibular disorders: study protocol for a randomized prospective single-blinded crossover trial.

BACKGROUND: Nowadays, stabilization splints for the management of bruxism and temporomandibular disorders (TMD) can be produced utilizing a digital workflow comprising a digital impression of the teeth, digital splint design, and computer-aided manufacturing of the splints. The latter is usually a milling process, however, more recently 3D printing gained popularity due to its better cost and time efficiency. It remains unknown whether 3D printed stabilization splints are inferior to milled splints regarding clinical outcomes. METHODS: This clinical trial assesses the non-inferiority of 3D printed occlusal splints compared to milled occlusal splints in a monocentric prospective randomized single-blinded crossover trial with two cohorts. One cohort includes 20 participants with bruxism, the other 20 participants with pain-related TMD, i.e., myalgia, myofascial pain, or arthralgia of the jaw muscles/the temporomandibular joint(s) diagnosed according to the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD). Michigan-type stabilization splints are fabricated in a digital workflow by milling or 3D printing using CE-marked materials within their intended purpose. The participants wear a milled and a 3D printed splint in a randomized order for 3 months each, with follow-up visits after 2 weeks and 3 months. Investigated outcome parameters are oral health-related quality of life (OHRQoL) evaluated by the Oral Health Impact Profile (OHIP-G14), participant satisfaction as rated on a visual analog scale, therapeutic efficacy, and technical result of the splints. In this context, therapeutic efficacy means antagonist wear and-in the TMD group-reduction of pain/disability assessed by the Graded Chronic Pain Scale (GCPS v2.0) and clinical assessment following the DC/TMD standard, while technical outcome measures splint fit, wear and fracture rate. DISCUSSION: The trial will provide important information on the clinical outcome of 3D printed stabilization splints in comparison to milled splints and will, therefore, enable an evidence-based decision in favor of or against a manufacturing process. This, in turn, will guarantee for a maximum of the patient's OHRQoL during splint therapy, therapeutic efficacy, and longevity of the splints. TRIAL REGISTRATION: German Clinical Trials Register (DRKS) DRKS00033904. Registered on March 15, 2024.

The Prevalence of Temporomandibular Disorders Among Dental and Medical Students in Taif, Saudi Arabia: A Cross-Sectional Study.

Objectives  This study was undertaken to investigate the prevalence of temporomandibular disorders (TMDs) and the impact of various contributing factors among undergraduate healthcare students in the region of Taif, Saudi Arabia. Methods A total of 100 undergraduate students were recruited from both the College of Medicine and the College of Dentistry at Taif University, Taif, Saudi Arabia. Data were collected on demographic parameters and the Helkimo's index (anamnestic {Ai} and clinical dysfunction {Di} component) using an anonymous self-administered questionnaire, as well as clinical examinations.  Results A significantly high prevalence (97%) of TMDs was observed among the sampled students, with most of them (44.0%) experiencing severe symptoms that might negatively impact their quality of life. On clinical examinations, most of the students (75.0%) showed signs of mild clinical dysfunction, which might indicate an early stage of TMD. Moreover, factors that include older age, majoring in "dentistry" studies, being allergic, having oral habits, poor mental health, and previous COVID-19 infections were found to be significantly associated with TMDs. Conclusion The findings indicate a relatively high TMD prevalence among the sampled undergraduate healthcare students, especially those studying "dentistry". Curriculum modifications, coupled with more awareness and education, are recommended to achieve early diagnosis and help in reducing the incidence of TMD among this population.

Critical Appraisal of Clinical Trials Evaluating Physical Therapy Treatments for Temporomandibular Disorders: A Scoping Review.

BACKGROUND: Physical therapy seems the most promising treatment for temporomandibular disorders (TMD), although their effectiveness is controversial in general, due to high heterogeneity regarding study designs, applied treatments and outcomes measures. OBJECTIVES: The aim of this scoping review is to analyse the methodological characteristics of clinical trials evaluating physical therapy treatments in subjects with TMD. METHODS: A systematic search was conducted in Medline/PubMed, SPORTDiscus, Scopus, Web of Science, SciELO, Cochrane, ScienceDirect and EMBASE databases on 31 October 2023. Clinical trials evaluating physical therapy interventions in patients older than 18 years with TMD, published in English or Spanish languages. Data regarding content reporting of study designs, sample characteristics, interventions and outcome measures was extracted. Descriptive summary statistics were reported. RESULTS: The search retrieved 15 322 records, and 136 were included. There were 107 randomised clinical trials, 5 non-randomised controlled trials and 24 non-controlled trials. Most studies had moderate to high risk of bias, small sample sizes (median, 44 subjects) and short follow-up periods (1-3 months). The most common diagnostic criteria used was the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) (48.9%). The most reported experimental interventions were manual therapy (40.4%), exercise (30.2%) and electrotherapy modalities (27.2%), and the most common outcome measure domains were pain (83.8%), range of movement (61.8%), disability (45.6%) and mechanosensitivity (29.4%). There was poor content reporting of experimental interventions. CONCLUSIONS: Current literature of clinical trials of physical therapy interventions for TMD has moderate to high risk of bias, poor content reporting, small sample size and short-term follow-ups which limit internal and external validity, as well as applicability into clinical practice.

Stress is simultaneously related to sleep and temporomandibular disorders.

PURPOSE: This study aimed to clarify the relationship between the oral environment and psychological factors as predictor variables of sleep quality, in addition to inferring the relevant mechanisms of sleep and temporomandibular disorders (TMDs) by analyzing the relationship between TMDs and stress. METHODS: This cross-sectional study analyzed data from 1,032 participants, comprising 420 men and 612 women, from the 2017 Iwaki Health Promotion Project using multiple regression analysis. The primary endpoints were the scores of each item in the Pittsburgh Sleep Quality Index (PSQI) and its sum. Predictor variables included the number of teeth; TMDs; stress, assessed using the World Health Organization-5 (WHO-5); sleep bruxism; and oral health-related quality of life, assessed using the oral health impact profile-14 (OHIP14). The confounding factors included age, body mass index, and alcohol intake. RESULTS: Multiple regression analysis revealed that TMDs (ß value = 0.293, p = 0.034) and stress (ß value = 1.3, p < 0.001) were significantly correlated with the PSQI total score. In addition, TMDs were significantly correlated with stress (ß value = 0.076, p = 0.007). CONCLUSION: The significant relationship between sleep and TMDs suggests that mental stress contributes to the development sleep disorders and consequently is associated with the development of TMD symptoms.

Sleep bruxism in children main methods of treatment: a systematic review with meta-analysis.

Sleep bruxism is both masticatory muscle activities characterized by repeated or prolonged tooth contact as well as bracing or thrusting of the jaw. This meta-analysis evaluates the differences between sexes and which therapy is most effective in treating bruxism. A literature search was performed on PubMed, Lilacs, Web of Science and Scopus, and articles published from 2000 to 2022 were considered according to the keywords entered. The term "Bruxism" has been combined with "Children" using the boolean connector AND. At the end of the research, 1462 studies were identified from the search conducted on the three engines. Only four were chosen to draw up the present systematic study. The Forrest plot found that photo biomodulation therapy has a higher efficacy (Odds Ratio (OR) 0.10; 95% Confidence Interval (CI) from 0.03 to 0.43), followed by treatment with hydroxyzine (OR 0.19; 95% CI from 0.03 to 1.04). The average between girls and boys with bruxism is 18.5 for boys and 19.5 for girls. This meta-analysis showed that treatment by photobiomodulation has more significant effects on bruxism, followed by treatment with hydroxyisalazine. However, this meta-analysis has limitations due to the diversity of treatment evaluation methods.

Comparison of the effects of acupuncture methods on the temporomandibular disorder: A network meta-analysis.

OBJECTIVES: A network meta-analysis (NMA) was applied to compare the therapeutic effect of different acupuncture methods on temporomandibular disorder (TMD). MATERIALS AND METHODS: A computer retrieval was carried out in the English databases of Cochrane, PubMed, Embase and Web of Science, as well as the Chinese databases of CNKI, Wanfang and VIP for randomized controlled trials on the effect of acupuncture on TMD, with a retrieval deadline of January 21, 2024. Data analysis was conducted using R software and Bayesian method. The pain score served as the primary outcome measure, with the mouth opening as the secondary outcome measure. RESULTS: Thirty-five articles were included in the analysis, involving 1937 TMD patients. The NMA results suggested that DN-PT had the best effect on relieving pain and improving mouth opening. (Description of all abbreviations in Supplementary Material S3). CONCLUSIONS: Based on the available evidence, the results of the NMA suggest that DN-PT is most effective in relieving TMD pain and increasing mouth opening. However, due to the fact that some acupuncture therapies are only reported in a small number of research reports, this may lead to an increase in the randomness of the results and a decrease in the reliability.

Physical therapy and non-surgical manual disc reduction combined with anterior repositioning splint for acute disc displacement without reduction of the temporomandibular joint in adolescents.

OBJECTIVES: Current studies on the treatment of adolescent patients with disc displacement without reduction (DDWOR) are limited by short follow-up periods and small sample sizes, and there are few comparative studies on the efficacy of conservative treatment with and without disc reduction for acute DDWOR. This study compared the therapeutic effects of two conservative treatment methods: physical therapy alone and physical therapy combined with non-surgical manual disc reduction and anterior repositioning splints (ARS), in adolescent patients with acute DDWOR. MATERIALS AND METHODS: This retrospective study included adolescent patients with DDWOR who underwent physical therapy at the Temporomandibular Joint Rehabilitation Department of the Shanghai Ninth People's Hospital from January 2018 to December 2021. Patient assessment data were collected before and after treatment. Patients were followed up through telephone and online questionnaires from March to August 2023. RESULTS: The results indicate that compared to physical therapy alone, the combination of physical therapy and non-surgical manual disc reduction with ARS showed better short-term efficacy, improved mouth opening, and better long-term pain control. Also, it may be effective in preventing degenerative joint disease. CONCLUSIONS: This combination therapy is recommended for clinical application in adolescent patients with acute DDWOR. CLINICAL RELEVANCE: The present research demonstrates the superior efficacy of physical therapy and non-surgical manual disc reduction combined with anterior repositioning splint in adolescent patients with acute DDWOR.

Clinical decision of centric relation.

Centric relation (CR) was used in the complete dentures for edentulous jaws firstly. Then, CR was gradually applied in the clinical diagnosis and treatment of dentate jaws. Regarding the application of CR in dentate jaws, there are many doubts about its rationality. For instance, should CR be the core of diagnosis and treatment of temporomandibular disorders? Should CR be used as the jaw position of establishing occlusion in occlusal reconstruction? Should CR serve as the target jaw position in orthodontic treatment? Meanwhile, varieties of CR clinical applications are objective. According to the existing evidence, this paper summarizes the applicable conditions of several main clinical situations with little controversy. We preliminarily put forward the decision tree for the clinical application of CR, which can be used as a reference in clinical practice.

Counselling for patients with a temporomandibular disorder: A scoping review and concept analysis.

BACKGROUND: An integral component of comprehensive temporomandibular disorder (TMD) treatment involves what is commonly referred to in literature as patient counselling or patient education. Despite its importance, a clear definition of the concept is lacking. OBJECTIVES: To describe the concept of counselling (i.e. what is it, what should it consist of, and when should it be given) through a concept analysis of the literature. ELIGIBILITY CRITERIA: All papers that include a description of counselling or education for TMD are included. SOURCES OF EVIDENCE: Literature searches were performed in the electronic databases PubMed, Cinahl, and PsycInfo. CHARTING METHODS: A qualitative analysis was done using the principle-based concept analysis approach, where descriptions of counselling from the included papers were analysed by the researchers. RESULTS: A total of 71 articles were included. Based on the qualitative analysis of the included articles and descriptions of counselling, the following content themes were identified: (1) general information on TMD; (2) overuse of the masticatory system; (3) posture education; (4) lifestyle and psychosocial factors; (5) exercise- and thermotherapy; and (6) additional information and therapies. CONCLUSIONS: A definition and framework of counselling for TMD has been provided, which can be used in the clinic, research, and educational programs.

Multidisciplinary treatment of a patient with TMJ ankylosis and a severe dentofacial discrepancy: A case report.

INTRODUCTION: Temporomandibular joint (TMJ) ankylosis is a debilitating condition characterised by the fusion of bony or fibrous tissues in the TMJ, resulting in restricted mouth opening, functional challenges and facial deformities. This report highlights the complexity and multifaceted nature of TMJ ankylosis and emphasises the significance of early intervention and a multidisciplinary approach. Distraction osteogenesis has emerged as a successful method for managing TMJ ankylosis and associated facial asymmetry. Post-distraction orthodontic management is essential to address occlusal changes, including posterior open bite and crossbite. DIAGNOSIS AND TREATMENT PLAN: A 17-year-old boy with unilateral right-sided TMJ ankylosis presented with restricted mouth opening, facial asymmetry and functional difficulties. Multidisciplinary treatment planning involved distraction osteogenesis, condylectomy, coronoidectomy and orthodontic correction to achieve proper occlusion and facial aesthetics. RESULTS: The treatment significantly improved facial aesthetics, mouth opening, occlusion and the patient's confidence and self-esteem. CONCLUSION: This case report underscores the complexity of TMJ ankylosis and the need for a comprehensive approach, including surgical and orthodontic interventions. Collaboration among healthcare professionals and ongoing research is vital to refine treatment approaches and improve the quality of life for patients with TMJ ankylosis.

The Potential of Percent Agreement as an Adjunctive Diagnostic Tool for Acute Temporomandibular Disorder.

Background/Objectives: It is well established that individuals with chronic temporomandibular disorder (TMD) exhibit differences in their physical and psychosocial characteristics from those with acute TMD. However, few studies have analyzed the physical and psychosocial characteristics of patients with acute TMD. The objective of this cross-sectional study is twofold: first, to ascertain whether there are differences in physical and psychosocial factors among patients with acute TMD based on the percent agreement between patient-reported pain sites and pain sites identified through standardized palpation and, second, to determine the potential of percent agreement as a diagnostic and prognostic factor. Methods: We analyzed physical and psychosocial factors in 309 patients diagnosed with acute TMD. Of these, 171 patients were selected for an analysis of their response to treatment. These patients were divided into three groups based on their percent agreement: Group A (agreement under 80%), Group B (agreement 80-89%), and Group C (agreement 90% or over) in the initial analysis and Group a (agreement under 80%), Group b (agreement 80-89%), and Group c (agreement 90% or over) in the subsequent analysis. This study was approved by the Ethics Committee of Pusan National University Dental Hospital (IRB No. 2023-05-011, 25 May 2023). Results: The lower the percent agreement, the greater the parafunctional oral habits, stress, chronicity, somatization, depression, anxiety, and number of painful sites. A lower percent agreement was associated with poorer treatment outcomes. The percent agreement demonstrated a 41.2% capacity to predict residual pain after treatment. Conclusions: Clinicians can utilize percentage agreement as an adjunctive diagnostic tool to provide more suitable treatments to patients.

Up-regulation of IL-1ß and sPLA2-III in the medial prefrontal cortex contributes to orofacial and somatic hyperalgesia induced by malocclusion via glial-neuron crosstalk.

The medial prefrontal cortex (mPFC) has been identified as a key brain region involved in the modulation of chronic pain. Our recent study demonstrated that unilateral anterior crossbite (UAC) developed the comorbidity model of temporomandibular disorders (TMD) and fibromyalgia syndrome (FMS), which was characterized by both orofacial and somatic hyperalgesia. In the present study, UAC rats exhibited significant changes in gene expression in the mPFC. Enrichment analysis revealed that the significantly involved pathways were cytokines-cytokine receptor interaction and immune response. The expression of group III secretory phospholipase A2 (sPLA2-III) was significantly increased in the mPFC of UAC rats. Silencing sPLA2-III expression in the mPFC blocked the orofacial and somatic hyperalgesia. Immunofluorescence showed that sPLA2-III was mainly localized in neurons. The expression of interleukin-1ß (IL-1ß) in the mPFC significantly increased after UAC. Injection of IL-1ß antibody into the mPFC blocked orofacial and somatic hyperalgesia. IL-1ß was mainly localized in microglia cells. Furthermore, injection of IL-1ß antibody significantly reduced the expression of sPLA2-III. These results indicate that neuroinflammatory cascade responses induced by glial-neuron crosstalk in the mPFC may contribute to the development of TMD and FMS comorbidity, and IL-1ß and sPLA2-III are identified as novel potential therapeutic targets for the treatment of chronic pain in the comorbidity of TMD and FMS.

Sleep misperception in women with myofascial temporomandibular disorder.

STUDY OBJECTIVES: Temporomandibular disorders (TMD) were linked to poor sleep on the Pittsburgh Sleep Quality Index (PSQI), whereas polysomnography (PSG) revealed no major sleep disturbances, implying sleep state misperception (SSM). This study investigates SSM in TMD and control participants; correlates SSM with objective short sleep duration (SSD), depression symptoms, daytime sleepiness, and orofacial pain; and compares objective SSD between the groups. METHODS: General linear models were used to compare second-night PSG total sleep time (TST), sleep latency (SL), sleep efficiency (SE) and wake after sleep onset (WASO) with homologous PSQI-derived variables in 124 women with myofascial TMD and 46 age and BMI matched controls. PSQI variables were regressed onto objective SSD, depression symptoms, daytime sleepiness, and pain. Lastly, objective SSD was related to TMD presence. RESULTS: Compared to controls, TMD cases misperceived SE (p = 0.02); depression symptoms explained PSQI-derived SE (p = 0.002) and mediated the effect of pain (p <.001). PSQI variables were unrelated to respective PSG measures or objective SSD, except a significant subjective-objective correlation in SE among controls only (p = 0.002). Objective SSD was more frequent in TMD cases (p = 0.02, OR = 2.95), but it was unrelated to depression symptoms, daytime sleepiness or pre-PSG pain. CONCLUSIONS: The study demonstrates misperception of SE among TMD cases, which was accounted for by depression symptoms. Objective SSD nearly tripled in TMD cases; however, it was unrelated to PSQI variables, depression, daytime sleepiness, or pain, suggesting that SSM and objective SSD are two independent sleep features in TMD.