High prevalence of orofacial pain in juvenile fibromyalgia as detected by a novel tool specifically devised for children and adolescents.

OBJECTIVES: To examine the prevalence of temporomandibular disorders (TMD) in patients with juvenile fibromyalgia syndrome (JFS) and identify TMD characteristics specifically associated to JFS. METHODS: Signs and symptoms of TMD were assessed using a novel clinical tool specifically devised for children that consists of: 1. a self-report multiple-choice questionnaire; 2. a protocol for the clinical examination of the orofacial region. Multivariate logistic regression model was used to identify TMD features associated with JFS. RESULTS: Thirty JFS patients (median age 15.5 years) and 45 healthy controls (median age 15.0 years) were included in this cross-sectional study. Orofacial pain was reported by 26 of 30 JFS patients (86.7%) and by 3 of 45 controls (6.7%; p<0.001). Pain on TMJ palpation was present in 18 of 30 JFS patients (60%) and in 5 of 45 controls (11.1%; p<0.001). Median values of maximum spontaneous mouth opening, voluntary active opening and assisted passive opening were significantly higher in JFS patients than in controls. On multiple regression analysis spontaneous orofacial pain (OR: 21.0; p=0.005), diffuse tenderness on palpation of the masticatory muscles (OR: 14.9; p=0.026) and TMJ hypermobility (OR 1.42; p=0.008) were independently associated with JFS. CONCLUSIONS: The high prevalence of TMD in JFS highlights the need for a broader interdisciplinary evaluation of JFS patients. TMJ hypermobility, in addition to orofacial and masticatory muscle pain, is an important clue for the diagnosis of TMD in adolescents with JFS. Elucidating the link between these disorders will advance individualised management and improve treatment efficacy.

Modern Approaches to the Treatment of Acute Facial Pain.

PURPOSE OF REVIEW: Acute facial pain presents a complex challenge in medical practice, requiring a comprehensive and interdisciplinary approach to its management. This narrative review explores the contemporary landscape of treating acute facial pain, delving into pharmacological, non-pharmacological, and advanced interventions. The significance of tailored treatment strategies, rooted in the diverse etiologies of facial pain, such as dental infections, trigeminal neuralgia, temporomandibular joint disorders, sinusitis, or neurological conditions like migraines or cluster headaches, is underscored. We particularly emphasize recent advances in treating trigeminal neuralgia, elucidating current treatment concepts in managing this particular acute facial pain. RECENT FINDINGS: Recent research sheds light on various treatment modalities for acute facial pain. Pharmacotherapy ranges from traditional NSAIDs and analgesics to anticonvulsants and antidepressants. Non-pharmacological interventions, including physical therapy and psychological approaches, play pivotal roles. Advanced interventions, such as nerve blocks and surgical procedures, are considered in cases of treatment resistance. Moreover, we explore innovative technologies like neuromodulation techniques and personalized medicine, offering promising avenues for optimizing treatment outcomes in acute facial pain management. Modern management of acute facial pain requires a nuanced and patient-centric approach. Tailoring treatment strategies to the individual's underlying condition is paramount. While pharmacotherapy remains a cornerstone, the integration of non-pharmacological interventions is essential for comprehensive care. Advanced interventions should be reserved for cases where conservative measures prove inadequate. Furthermore, leveraging innovative technologies and personalized medicine holds promise for enhancing treatment efficacy. Ultimately, a holistic approach that considers the diverse needs of patients is crucial for effectively addressing acute facial pain.

Does the Use of Botulinum Toxin in Treatment of Myofascial Pain Disorder of the Masseters and Temporalis Muscles Reduce Pain, Improve Function, or Enhance Quality of Life?

BACKGROUND: The efficacy of botulinum toxin for management of myofascial pain disorder (MPD) remains controversial. PURPOSE: The purpose was to determine if the use of onabotulinumtoxinA (onabotA) in patients with MPD reduces pain, improves function, or enhances quality of life (QoL). STUDY DESIGN, SETTING, AND SAMPLE: This is a multicenter, prospective, randomized, double-blinded, placebo-controlled clinical trial. Subjects with orofacial pain were screened for MPD as defined by the Diagnostic Criteria for Temporomandibular Disorders. PREDICTOR VARIABLE: The primary predictor variable was MPD treatment with random assignment to onabotA or placebo (saline). MAIN OUTCOME VARIABLE: The primary outcome variable was pain before treatment (T0) and at 1 month (T1) using a visual analog scale. Secondary outcome variables included pain at 2 months (T2) and 3 months (T3), maximal incisal opening (MIO), jaw function (jaw functional limitation scale), and QoL (Short Form 36) measured at T0, T1, T2, and T3. COVARIATES: Covariates included subject demographics, prior treatments, and temporomandibular joint signs/symptoms. ANALYSES: Descriptive and bivariate statistics included χ2 test, Fisher's exact test, or t-test. RESULTS: Seventy five subjects with a mean age of 37 (±11) and 35 (±12) years in the onabotA and placebo groups, respectively (P = .6). Females represented 32 (86%) and 29 (76%), respectively (P = .3). Mean visual analog scale pain score in the onabotA group was 58 (±15), 39 (±24), 38 (±23), and 38 (±20) at T0, T1, T2, and T3, respectively; and the placebo group was 54 (±14), 40 (±23), 34 (±20), and 36 (±22) at T0, T1, T2, and T3, respectively. There was no statistically significant difference in pain between groups at any time point (P = .36). There was no statistically significant difference between groups in MIO (P = .124), jaw function (P = .236), or QoL domains (P > .05) at any time point. Within-group improvement in pain was seen in both groups (P < .005). Within-group improvement in jaw function was seen in the onabotA (P = .007) and placebo (P = .005) groups. There was no within-group improvement in MIO or QoL with either group (P > .05). CONCLUSIONS: OnabotA and saline (placebo) injections both decrease pain and improve jaw function in subjects with MPD.

A critical look at outcome measures: Comparison between four dental research journals by use of a hierarchical model.

AIM: To assess the status quo of outcome measures used in treatment studies in Endodontics, and potentially identify strategies for improvement, by (i) systematically assessing the outcome measures using a conceptual model and (ii) comparing these with measures used in corresponding studies in the adjacent fields. METHODOLOGY: The International Endodontic Journal, Caries Research, The Journal of Clinical Periodontology and The Journal of Oral & Facial Pain and Headache were selected to cover four adjacent dental disciplines. In each journal, the 50 most recent consecutive publications fulfilling inclusion criteria were included. A hierarchical model for diagnostic imaging studies was modified to assess studies related to treatment. The model comprised six levels, with technical as the lowest level and societal as the highest. Extracted data included study origin, study type, and identified outcome measures. Fisher's Exact Tests with Bonferroni corrections compared studies. p < .05 was considered statistically significant. RESULTS: Amongst 756 publications, the 200 most recent studies matching the inclusion criteria were identified. Less than half (36.5%) assessed the clinical, patient, or societal aspects of treatment; 10.0% in International Endodontic Journal, 28.0% in Caries Research, 38.0% in Journal of Clinical Periodontology, and 70.0% in Journal of Oral & Facial Pain and Headache (p < .001). CONCLUSIONS: According to included publications, research on treatment within the endodontic field is mainly focusing on technical and biological outcomes. The benefits of patients and society were less frequently examined than in corresponding journals in adjacent disciplines. When designing studies, including higher-level outcomes should be considered.

Effectiveness of photobiomodulation and orofacial myofunctional therapy in orofacial pain disorders. A systematic review of randomized control trials.

Orofacial pain can significantly affect physical, psychological, and overall quality of life. This study aimed to compare the effectiveness of combining photobiomodulation (PBM) with orofacial myofunctional therapy (OMT) in managing orofacial pain disorders. An electronic search of randomized controlled trials in electronic databases was performed until March 2024. Randomized controlled trials (RCTs) focusing on PBM and OMT for the management of orofacial pain were included. Risk of bias across individual studies was performed using the Cochrane risk of bias tool for interventions. A total of 10 RCTs were included, out of which 7 RCTs revealed that the combined approach of PBM and OMT had a more pronounced impact on diminishing pain and enhancing functional activity in patients with orofacial disorders. One study reported significant increases in pressure pain threshold for TMJ, masseter, and anterior temporalis muscles at both sides in the post-treatment compared with the pre-treatment in both groups. The risk of bias was low in 7, moderate in 2, and high in 1 study. The efficacy of a combined modality treatment of PBM with OMT for orofacial pain disorder shows promising results. However, further randomized controlled trials with extended follow-up periods standardized PBM and OMT parameters are warranted to obtain firm conclusions.

Time-course of pain and salivary opiorphin release in response to oral capsaicin differ in burning mouth syndrome patients, temporomandibular disorders patients and control subjects.

OBJECTIVES: Opiorphin is an analgesic peptide released by salivary glands and capsaicin an agonist of TRPV1 receptors eliciting burning sensations. The primary objective of this study was to assess opiorphin release after stimulation of the tongue by capsaicin (STC). The secondary objectives were to compare opiorphin release after STC in 3 groups of subjects [healthy (CTRL), Burning Mouth Syndrome (BMS), painful Temporomandibular disorders (TMDp)] and pain evoked by STC in these 3 groups. MATERIALS AND METHODS: Salivary opiorphin was assessed with high-performance liquid chromatography at 3 different time points (baseline, after 5 min and 20 min of STC). Pain was self-reported on a (0-10) numeric rating scale. RESULTS: Three groups (N = 16) of adults were recruited at the Clinical Hospital Centre and School of Dental Medicine in Zagreb. Opiorphin levels were higher (1) in TMDp compared to CTRL in 1st (2.23 ± 1.72 pg/ul vs. 0.67 ± 0.44 pg/ul, p = 0.002) and 3rd sampling (2.44 ± 2.01 pg/ul vs. 0.74 ± 0.52 pg/ul, p = 0.020) and (2) within BMS group at 3rd sampling vs. baseline (p < 0.025). Pain scores were higher in BMS compared to TMDp (p < 0.025) and CTRL (p < 0.025). CONCLUSION: This study evidenced (1) a differential basal amount of opiorphin in two pain conditions and control subjects (2) a differential kinetic of release of opiorphin after STC in CTRL, BMS and TMDp (3) a differential pain perception after STC in BMS and TMDp vs. CTRL, which can provide a readout for animal models. CLINICAL RELEVANCE: The specific regulation of opiorphin release in patients with orofacial painful conditions provides valuable insights for clinicians and researchers in physiology and pathology and encourages further research in this area. TRIAL REGISTRATION: ClinicalTrials.gov NCT04694274. Registered on 01/05/2021.

Is it possible to extract primary maxillary molars without palatal injection?: a controlled clinical trial.

OBJECTIVES: The absolute necessity of a palatal injection for the extraction of primary maxillary molars has never been explored, despite the fact that it is widely known that children do not tolerate local anesthetic injections into the palatal tissue well. The aim of this study was to compare separately the perception of pain in the absence of palatal injection after anesthesia and maxillary primary molar tooth extraction using different anesthetic solutions and different post-anesthetic waiting times. MATERIALS AND METHODS: A single-blinded randomized controlled study was conducted in 78 participants (26 patients with palatal anesthesia (the control groups), and 26 patients with 5 min and 26 patients with 8 min post-anesthetic waiting time without palatal anesthesia (the study groups)). Subjective experiences of pain were evaluated separately after anesthesia and tooth extraction using the Visual Analog Scale (VAS) and the Wong-Baker Faces Pain Rating Scale (WBS). RESULTS: In terms of VAS scores obtained following administration of anesthesia, there was a statistically significant difference between the groups (p<0.05). VAS pain scores were reported to be lower in the groups without palatal anesthesia than in the groups with palatal anesthesia. No statistically significant difference was observed in VAS and Wong-Baker scores after tooth extraction between the groups with and without palatal anesthesia (P>0.05). CONCLUSIONS: While the pain reported following administration of anesthesia was found to be higher in the groups receiving palatal anesthesia, no difference was found between the groups in the pain reported after tooth extraction. CLINICAL RELEVANCE: Extraction of maxillary primary molars is possible without palatal injection by injecting 4% articaine or 2% lidocaine into the buccal vestibule of the tooth with a waiting time of 5 or 8 min.

Pain symptoms are associated with two-point discrimination threshold in patients with temporomandibular disorders.

OBJECTIVE: This study aimed to explore the associations of orofacial two-point discrimination (2-PD) test result with pain symptoms and psychological factors in patients with Temporomandibular Disorders (TMDs). METHODS: 193 patients with TMDs were included in this study. Patients' demographics, pain intensity, and psychological status were recorded. The 2-PDs in the bilateral temporal, zygomatic, mandibular, and temporomandibular joint (TMJ) regions of the patients were measured. Statistical analyses were conducted to observe the associations between variables. RESULTS: For Pain-related TMDs (PT) patients, Monthly Visual Analogue Scale (VAS-M) and Current Analogue Scale (VAS-C) were correlated with TMJ, zygomatic and temporal 2-PDs. Patients with PT tended to have higher TMJ 2-PDs[Right: ß = 1.827 mm, 95%CI(0.107, 3.548), P = 0.038], zygomatic 2-PDs[Right: ß = 1.696 mm, 95%CI(0.344, 3.048), P = 0.014], temporal 2-PDs[Left: ß = 2.138 mm, 95%CI(0.127, 4.149), P = 0.037; Right: ß = 1.893 mm, 95%CI(0.011, 3.775), P = 0.049]. Associations were also observed between VAS-C and TMJ 2-PDs[Left: ß = 0.780, 95%CI(0.190, 1.370), P = 0.01; Right: ß = 0.885, 95%CI(0.406, 1.364), P = 0.001], Zygomatic 2-PDs[Right: ß = 0.555, 95%CI(0.172, 0.938), P = 0.005]; VAS-M and TMJ 2-PDs[Left: ß = 0.812, 95%CI(0.313, 1.311), P = 0.002; Right: ß = 0.567, 95%CI(0.152, 0.983), P = 0.008], zygomatic 2-PDs[Left: ß = 0.405, 95%CI(0.075, 0.735), P = 0.016; Right: ß = 0.545, 95%CI(0.221, 0.870), P = 0.001], and temporal 2-PDs [Left: ß = 0.741, 95%CI(0.258, 1.224), P = 0.003; Right: ß = 0.519, 95%CI(0.063, 0.975), P = 0.026]. CONCLUSION: TMJ, zygomatic, and temporal 2-PDs were significantly associated with PT and pain intensity. Age, gender and psychological factors were not associated with orofacial 2-PDs. PT patients exhibited weaker tactile acuity compared to Non-PT patients. Further discussion on the underlying mechanism is needed. CLINICAL RELEVANCE: Orofacial tactile acuity of TMDs patients was associated with their pain symptoms, which researchers should take account into when performing 2-PD tests for TMDs patients. The 2-PD test can be considered as a potential tool along with the current procedures for the differentiations of PT and Non-PT.

Self-reported bruxism in patients with post-traumatic stress disorder.

OBJECTIVE: The present study aimed to investigate the association between self-reported awake/sleep bruxism, and orofacial pain with post-traumatic stress disorder (PTSD). METHODS: A case-control study with a convenience sample was designed. Participants were recruited from a university-based Trauma Ambulatory. The diagnosis of PTSD was established through a clinical interview and the Structured Clinical Interview (SCID-I/P). Thirty-eight PTSD patients and 38 controls completed the Research Diagnostic Criteria for Temporomandibular Disorders Axis-II to categorize awake/sleep bruxism and orofacial pain. Following this, we performed a short clinical examination of the temporomandibular joint and extraoral muscles. RESULTS: Adjusted logistic regression analysis showed that awake bruxism was associated with PTSD (OR = 3.38, 95% CI = 1.01-11.27, p = 0.047). Sleep bruxism was not associated with any covariate included in the model. In a Poisson regression model, PTSD (IRR = 3.01, 95% CI = 1.38-6.55, p = 0.005) and the muscle pain/discomfort (IRR = 5.12, 95% CI = 2.80-9.36, p < 0.001) were significant predictors for current orofacial pain. CONCLUSIONS: PTSD was associated with self-reported awake bruxism and low-intensity orofacial pain. These conditions were frequent outcomes in patients previously exposed to traumatic events. CLINICAL RELEVANCE: We suggest including a two-question screening for bruxism in psychiatry/psychology interviews to improve under-identification and to prevent harmful consequences at the orofacial level.

Influence of malocclusion on sleep bruxism and orofacial pain: data from a study in school children.

OBJECTIVES: This cross-sectional school-based study explored the influence of malocclusion on temporomandibular disorders (TMD) pain complaints, and whether this association would be mediated by sleep bruxism in a representative sample of 7- to 8-year-old children. METHODS: Path analysis estimated direct, indirect, and total effects of occlusal features on sleep bruxism and TMD pain in 7- to 8-year-old children. Occlusal features were assessed with Dental Aesthetic Index (DAI), orofacial pain complaints using the TMD pain screener, possible sleep bruxism based on self-reports, and probable sleep bruxism based on self-reports combined with clinical findings. Structural equation modeling analyzed data with confounding factors. RESULTS: From 580 participants, possible sleep bruxism was observed in 136 children (31.5%), probable sleep bruxism in 30 children (6.7%), and TMD pain complaints in 78 children (13.8%). Malocclusion had no direct effect on either possible sleep bruxism [standardized coefficient (SC) 0.000; p = 0.992], or TMD pain complaints (SC - 0.01; p = 0.740). When probable sleep bruxism was set as the mediator of interest, malocclusion did not directly affect probable sleep bruxism (SC 0.01; p = 0.766), nor TMD pain complaints (SC - 0.02; p = 0.515). A direct effect of probable sleep bruxism on TMD pain complaints was observed with an SC of 0.60 (p < 0.001). However, in neither case, malocclusion indirectly affected TMD pain complaints via bruxism. CONCLUSION: Malocclusion in 7- to 8-year-old children did not directly influence possible or probable sleep bruxism or TMD pain complaints. Instead, probable sleep bruxism was strongly associated with TMD pain complaints. CLINICAL SIGNIFICANCE: The impact of occlusal features on TMD pain complaints and bruxism has been a long-standing controversy in dentistry. However, the scientific literature linking this association may be inconsistent, mainly due to biased sample selection methods with inadequate consideration of confounders. Further research should try to identify additional risk factors for TMD pain in addition to probable sleep bruxism in children.

Constructing the brief diagnostic criteria for temporomandibular disorders (bDC/TMD) for field testing.

BACKGROUND: Despite advances in temporomandibular disorders' (TMDs) diagnosis, the diagnostic process continues to be problematic in non-specialist settings. OBJECTIVE: To complete a Delphi process to shorten the Diagnostic Criteria for TMD (DC/TMD) to a brief DC/TMD (bDC/TMD) for expedient clinical diagnosis and initial management. METHODS: An international Delphi panel was created with 23 clinicians representing major specialities, general dentistry and related fields. The process comprised a full day workshop, seven virtual meetings, six rounds of electronic discussion and finally an open consultation at a virtual international symposium. RESULTS: Within the physical axis (Axis 1), the self-report Symptom Questionnaire of the DC/TMD did not require shortening from 14 items for the bDC/TMD. The compulsory use of the TMD pain screener was removed reducing the total number of Axis 1 items by 18%. The DC/TMD Axis 1 10-section examination protocol (25 movements, up to 12 sets of bilateral palpations) was reduced to four sections in the bDC/TMD protocol involving three movements and three sets of palpations. Axis I then resulted in two groups of diagnoses: painful TMD (inclusive of secondary headache), and common joint-related TMD with functional implications. The psychosocial axis (Axis 2) was shortened to an ultra-brief 11 item assessment. CONCLUSION: The bDC/TMD represents a substantially reduced and likely expedited method to establish (grouping) diagnoses in TMDs. This may provide greater utility for settings requiring less granular diagnoses for the implementation of initial treatment, for example non-specialist general dental practice.

Mental health and jaw function of patients with anterior disc displacement with reduction.

BACKGROUND: The mental health of patients with temporomandibular disorder or other jaw dysfunction is a primary concern in clinical practice, but the extent of these symptoms in this patient subset is not yet well understood. OBJECTIVES: This cross-sectional study aimed to compare the mental health and jaw function between patients with anterior disc displacement with reduction (ADDWR) and healthy individuals. METHODS: In total, 170 patients with ADDWR and 163 healthy participants enrolled in this study from March 2020 to December 2021. All participants completed a single assessment, including a pain rating and several questionnaires to assess jaw dysfunction, depression, and anxiety. All scores and the grade distribution of somatization, depression and anxiety were analysed between groups. RESULTS: Significant differences were found in measures of pain, jaw function and somatization; the ADDWR group had significantly higher pain and functional jaw limitations than the healthy group. The grade distribution of somatic symptoms also differed between groups: the distribution of patients who reported mild and above scores in the ADDWR group was significantly higher than that of the healthy group. Depression and anxiety scores or grade distributions were not significantly different by group. CONCLUSION: The jaw function of patients seeking treatment for ADDWR was lower than that of non-TMD individuals. They did not show high anxiety and depression symptoms, but their somatic symptoms were more apparent.

Are orofacial pain and xerostomia associated with differences in diet, sensory perception, appetite and enjoyment of eating?-An explorative study.

BACKGROUND: Orofacial function is believed to influence an individual's diet. knowledge on appetite and enjoyment of eating in orofacially impaired individuals is scarce. OBJECTIVE: We aimed to explore potential associations between impaired orofacial function, that is, orofacial pain, jaw function limitation and xerostomia, respectively, and diet, appetite, taste perception, as well as the enjoyment of eating. METHODS: An online questionnaire was shared among Aarhus University's dental patients and through social media. A convenience sample of 351 individuals responded (97 men, 254 women, aged 18-86 years). Participants were divided into groups with and without orofacial pain or xerostomia based on responses. Questions about food intake, appetite, meal-related well-being and oral/general health were included. Data were analysed using Mann Whitney U tests, Spearman's correlation, Chi-square tests, and t-tests. RESULTS: Participants with (n = 123) and without (n = 228) orofacial pain differed significantly regarding age, perceived oral/general health, frequency of consumption of for example cooked vegetables and raw whole fruit, perception of sourness, chewiness, and nausea/pain when eating (p ≤ .031). Participants with (n = 101) and without (n = 250) xerostomia differed significantly regarding perceived oral/general health, intake of prepared fruit, alcohol, ice cream/mousse/pudding, general appetite, intake of breakfast and liquid snacks, nausea/pain when eating, taste and chewiness of food (p ≤ .038). CONCLUSION: Diet, appetite, taste and sensory perception, as well as enjoyment of eating of individuals reporting orofacial pain and/or xerostomia differed slightly to that of individuals free of such symptoms. However, due to the explorative nature of this study, the results should be interpreted with caution pending further research on potential long-term effects on nutritional status and well-being.

Genetic influence on treatment outcomes in patients with pain-related temporomandibular disorders.

BACKGROUND: Single nucleotide polymorphisms (SNPs) may influence pain susceptibility and impact treatment response in pain-related temporomandibular disorders (TMDp). OBJECTIVE: Explore the role of COMT (rs4646310, rs6269, rs4818, rs4680) and OPRM1 (rs1799971) genotypes in regulating treatment response. METHODS: Sixty TMDp patients (55 females and 5 males), diagnosed with the Diagnostic Criteria for TMD (DC/TMD), underwent standardised treatment (information and education, home physical therapy, occlusal splint) for 6 months. Treatment outcomes included: pain intensity, pain-free mouth opening, jaw functional limitation, depression, and anxiety. Genotyping for COMT and OPRM1 SNPs was performed using DNA from buccal mucosa swabs and TaqMan assays. Statistical analysis was carried out to compare the changes in treatment outcomes and the influence of genotypes on treatment response. RESULTS: Significantly less pain reduction was observed in minor allele carriers of rs4646310, and rs4680 compared to dominant homozygous (p < .025). Minor allele carriers of rs1799971 and rs4646310 demonstrated worsening in pain-free mouth opening while dominant homozygous exhibited improvement (p < .025). Significantly less anxiety reduction was observed in minor allele carriers of rs4646310 compared to dominant homozygous (p = .003). Of the all variables assessed in the regression model, carrying a minor allele of rs1799971 predicted a poorer treatment response considering pain-free mouth opening while carrying a minor allele of rs4646310 predicted less pain and less anxiety reduction. CONCLUSION: Our findings indicate that certain SNP variants of the COMT and OPRM1 genes were associated with poorer treatment response and may therefore play a significant role in the classification of TMDp patients. Also, assessment of patient genotype could potentially aid in predicting treatment response.

Bruxism and oro-facial pain not related to temporomandibular disorder conditions: Comorbidities or risk factors?

INTRODUCTION: Bruxism has historically been of particular interest to the field of dentistry, primarily due to the inferred damage it may cause to the dentition and supporting periodontal structures. The definition of bruxism itself has undergone multiple changes over time. In addition, the effects of bruxism as it relates to oro-facial pain conditions has remained a debatable topic. PURPOSE: To review the available literature relating to bruxism and non-temporomandibular disorder (TMD) pain conditions. METHODS: A literature search was conducted with the assistance of an expert librarian. The following databases were reviewed: PubMed, MEDLINE, EMBASE and Google Scholar. For additional references, articles were also retrieved by hand search from the selected papers. Any articles that were not published in English, or the focus were related to temporomandibular disorders were excluded. CONCLUSIONS: While bruxism and certain headache conditions do tend to occur together frequently, evidence relating to any clear common pathophysiological mechanism has yet to be fully elucidated. Robust evidence as it relates to the relationship between bruxism and other non-TMD oro-facial pains is also lacking.

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

BACKGROUND: Research on temporomandibular disorder (TMD) responsiveness is scarce and limited regarding patients' representativeness. OBJECTIVE(S): 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

The effect of different pain characteristics on jaw functional limitations in patients with temporomandibular disorders.

BACKGROUND: Patients with painful temporomandibular disorders (TMD) more often experience jaw functional limitations. The study of jaw functional limitations should be primarily focused on painful TMD. OBJECTIVES: The impact of TMD pain characteristics (source, chronicity and intensity) on jaw functional limitations were evaluated using Jaw Functional Limitation Scale (JFLS). METHODS: This cross-sectional study reviewed the dental records and self-report questionnaires of patients with painful TMD. The pain source, chronicity and intensity were evaluated to study the TMD pain characteristics. The jaw functional limitations were analysed using the Thai version of the JFLS. RESULTS: A total of 176 patients with painful TMD were included in this study. The jaw functional limitations were affected only by pain intensity. Patients with TMD with severe pain intensity had significantly higher jaw functional limitations than those with mild-to-moderate pain intensity (p < .05). A significant association was observed between pain intensity and jaw functional limitations (p < .05). Mastication was highly restricted by pain intensity (odd ratio = 1.39, 95% confidence interval = 1.16-1.67). CONCLUSION: The present study found a significant effect of TMD pain intensity on jaw functional limitations. Patients with severe TMD pain intensity were more likely to experience jaw functional limitations, particularly mastication limitation. Management focusing on reduction of pain intensity may improve jaw functions in patients with TMD.

The effectiveness of cervical rehabilitation interventions for pain in adults with myogenic temporomandibular disorders: A systematic review and meta-analysis.

OBJECTIVE: Little evidence exists for the most effective conservative treatment approach for adults with myogenic temporomandibular disorders (MTMD). We aim to assess the effectiveness of cervical rehabilitation interventions on pain intensity and sensitivity in adults with MTMD compared to comparison intervention such as placebo, sham treatment, education or no intervention. METHODS: For this systematic review and meta-analysis, we searched PubMed, EMBASE, Medline, PEDro databases, forward and backward citations and grey literature studies through PROSPERO, clinical trials and data registries without language or date restrictions between inception and 1 December 2021. We selected randomised controlled trials (RCTs) based on adult populations with MTMD who had a cervical rehabilitation intervention which was defined as any conservative intervention targeting the anatomical structures of the cervical spine. The primary outcome measures for pain were self-reported pain intensity and pain sensitivity through the pressure pain threshold (PPT) of the masseter and temporalis muscles. Secondary outcome measures of maximal mouth opening (on MMO) were included. Included studies were assessed for bias with the Cochrane risk of bias tool for randomised trials. Evidence from RCTs was synthesised to determine treatment effect size as differences between standardised mean difference (SMD) for changes in pain intensity, PPT and MMO comparing adults with MTMD who were treated with cervical rehabilitation interventions compared to a control group. This study is registered on Prospero, number CRD 42021289299. RESULTS: Our general search yielded 2647 studies where seven RCTs met eligibility criteria with low to some concerns in their risk of bias. Pain intensity (five studies, n = 223, SMD -0.98, 95% CI -1.67 to -0.28, I2 = 79%), PPT of the masseter muscle (six studies, n = 395, SMD 0.64, 95% CI 0.43 to 0.86, I2 = 90%) and the temporalis muscles (five studies, n = 295, SMD 0.76, 95% CI 0.07 to 1.45, I2 = 84%) showed large treatment effect estimates favouring cervical rehabilitation interventions compared to no treatment, sham cervical treatment, patient education or non-cervical neuromuscular techniques. Compared to control interventions, one type of cervical rehabilitation intervention, cervical manual therapy alone or in combination with a neck exercise program was associated with statistically significant, large treatment effect estimates on pain intensity (four studies, n = 203, SMD -1.52, 95% CI -2.50 to -0.55). CONCLUSIONS: This review found that in the short-term, cervical rehabilitation interventions especially upper cervical MT alone or in combination with a neck exercise program are effective in improving multiple pain outcomes in adults with MTMD. However, further research is needed to measure the long-term effects of this type of intervention.

Prevalence of temporomandibular disorders in clear aligner patients using orthodontic intermaxillary elastics assessed with diagnostic criteria for temporomandibular disorders (DC/TMD) axis II evaluation: A cross-sectional study.

BACKGROUND: The objective of this investigation is to assess the relationship between the utilisation of orthodontic intermaxillary elastics and temporomandibular disorder (TMD) symptoms in clear aligner patients and to examine the correlation between the elastic usage time with the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD)-Axis II Evaluation Forms. METHODS: This study was carried out on a total of 40 clear aligner patients using intermaxillary elastics in the experimental group and 30 clear aligner patients who did not use any intermaxillary elastics in the control group. The data were evaluated using the Mann-Whitney U, chi-square, Fisher's exact chi-square, and Fisher Freeman Halton exact chi-square tests. RESULTS: The characteristic pain intensity, mastication, mobility, communication, global and PHQ-9 scores of the experimental group were significantly higher than those of the control group (p < .05). The characteristic pain intensity score, interference score and chronic pain grade score of patients using Class III elastics were statistically significantly higher than those of patients using Class II elastics (p < .05). Patients who used elastics for less than 6 months had statistically significantly higher PHQ-9 scores than those who used elastics for more than 6 months (p < .05). CONCLUSIONS: Orthodontic treatment may affect occlusion, bite force and jaw movement, which may cause or worsen TMD symptoms, and the DC/TMD questionnaires can determine if orthodontic patients acquire TMD by assessing their psychosocial state and pain-related problems.

Pain and salivary biomarkers of stress in temperomandibular disorders were affected by maxillary splints.

BACKGROUND: Longitudinal intervention studies on treatment options in temporomandibular dysfunction (TMD) including self reports and salivary biomarkers of stress are rare and the exact therapeutic function of occlusal splints widely unknown. METHODS: We examined the therapeutic effects of a Michigan splint with occlusal relevance in patients with TMD using a placebo-controlled, delayed-start design. Two intervention groups received a Michigan splint, while one of them had a placebo palatine splint for the first 3 weeks. We collected pain intensities (at rest and after five occlusal movements), salivary measures associated with stress (cortisol and alpha-amylase) and self-reported psychological distress (stress, anxiety, catastrophizing) at baseline and 3 and 7 weeks after onset of intervention. RESULTS: At baseline, we observed increased pain intensity and psychological distress in TMD patients compared to 11 matched healthy controls. Baseline anxiety was linked to movement pain intensity through stress. Over therapy reductions in pain intensity and morning cortisol were more pronounced in those patients starting immediately with the Michigan splint, while psychological distress decreased similarly in both groups. CONCLUSION: Our results suggest that perceived stress plays a role for the association between anxiety and TMD pain and underlines the need for an interdisciplinary perspective on the pathogenesis and therapy of TMD in a setting where psychotherapeutic knowledge is still scarce or rarely applied.