Journal of Oral & Facial Pain and Headache, 03/2020

Aims: To investigate the effectiveness of a novel jaw-opening–force measuring device as a screening tool to aid in the diagnosis of temporomandibular disorders (TMD). Methods: Symptomatic TMD patients (n = 58) and control TMD-free participants (n = 56) were screened by an oral medicine specialist according to the Diagnostic Criteria for TMD (DC/TMD). TMD patients were divided into three subcategories based on TMD symptoms (myofascial pain, disc displacement, and both combined). Jaw-opening forces were measured in both groups with an adjustable head device connected to a 1,000-N–load cell. Seven attempts were recorded at 10-second intervals by a data-capturing system. The geometric mean force values were obtained after discarding the first and last attempts. Results: TMD-free participants had greater jaw-opening forces than TMD patients both without and with adjustments for age, sex, height, and weight (both P .001). The geometric mean ± standard deviation values for TMD patients were 18.5 ± 1.62 N and 47.7 ± 1.53 N for TMD-free participants. Differences in jaw-opening forces among the three TMD subcategories were not statistically significant; however, patients with disc displacement (23.7 ± 1.46 N) had greater jaw forces than patients with myofascial pain (17.0 ± 1.74 N) and both myofascial pain and disc displacement (17.0 ± 1.56 N). Conclusion: This study demonstrated that differences in jaw-opening forces could be used as a diagnostic tool for TMD. Future studies should explore the potential of this device to measure improvement in jaw-opening forces following Keywords: diagnostic tool, jaw-opening forces, myofascial pain, temporomandibular disorders, temporomandibular joint

Within the orofacial pain discipline, the most common group of afflictions is temporomandibular disorders (TMD). The pathologic and functional disorders included in this condition closely resemble those that are seen in the orthopedic medicine branch of the medical profession, so it would be expected that the same principles of orthopedic diagnosis and treatment are applied. Traditional orthopedic therapy relies on a "Two Pathway" approach involving conservative and/or surgical treatments. However, over the course of the 20th century, some members of the dental community have created another way of approaching these disorders— referred to in this paper as the "Third Pathway"—based on the assumption that signs and symptoms of TMD are due to a "bad" relationship between the mandible and skull, leading to a variety of irreversible occlusal or surgical corrective treatments. Since no other human joint is discussed in these terms within the orthopedic medicine communities, it has become progressively clear that the Third Pathway is a unique and artificial conceptual creation of the dental profession. However, many clinical studies have utilized the medically oriented conservative/ surgical Two-Pathway model to diagnose and treat TMD within a biopsychosocial model of pain. These studies have shown that TMD comprise another domain of orthopedic illness that requires a medically oriented approach for good outcomes while avoiding the irreversible aspects of the Third Pathway. This review presents historical and current evidence that the Third Pathway is an example of unorthodox medicine that leads to unnecessary overtreatment and further proposes that it is time to abandon this approach as we move forward in the TMD field. Keywords: dental occlusion, jaw repositioning, orthopedics, temporomandibular disorders, TMD

Aims: To assess the effect of geographic tongue (GT) on taste, salivary flow, and pain characteristics in burning mouth syndrome (BMS) to determine whether GT is a contributing factor to BMS and whether BMS and GT represent similar patient populations. Methods: A retrospective chart study was conducted. Patients with a diagnosis of BMS or BMS/GT were included. Data regarding smell testing, spatial taste-testing, salivary flow, oral pH, and subjective pain rating on a generalized labeled magnitude scale (gLMS) were collected. Results: No significant differences in age, gender, oral pH, smell, or pain were found between groups. Stimulated and unstimulated salivary flow were significantly lower in BMS/GT. Taste responses to all taste stimuli and to ethanol were significantly lower in BMS, with the exception of sour at the fungiform papillae. Conclusion: BMS and BMS/GT present with similar clinical pain phenotype and demographics; however, taste was more intact in BMS/GT, suggesting that GT may be a contributing factor in the development of BMS through a mechanism that does not involve taste. Keywords: burning mouth syndrome, geographic tongue, pain intensity, taste

Aims: To evaluate the available literature on structural and functional brain abnormalities in trigeminal neuralgia (TN) using several brain magnetic resonance imaging (MRI) techniques to further understand the central mechanisms of TN. Methods: PubMed and Web of Science databases and the reference lists of identified studies were searched to identify potentially eligible studies through January 2019. Eligible articles were assessed for risk of bias and reviewed by two independent researchers. Results: A total of 17 articles meeting the inclusion criteria were included in this study. The methodologic quality of the included studies was moderate. A total of 10 studies evaluated structural gray matter (GM) changes, and there was reasonable evidence that the GM of some specific brain regions changed in TN patients. In addition, there was a significant change in the root entry zone of the trigeminal nerve and in several regions of white matter. Functional changes in resting state were assessed in 9 studies. TN patients showed increased activation of resting state, and this activation was reduced in specific brain regions. There were several studies that focused on the correlation between functional parameters or strength of functional connectivity and clinical features (eg, visual analog score and pain duration), but each study focused on different brain areas or different functional connectivities within the brain. Conclusion: There is moderate evidence that TN patients show structural brain differences in specific cortical and subcortical regions. In addition, TN patients show changes in pain-related functional connections in the resting state. Future research should focus on longitudinal designs and integration of different brain-imaging techniques. Keywords: functional connectivity, gray matter, trigeminal neuralgia, white matter

Exacerbation of nighttime sleep-related oromotor activity is often recognized as a relevant clinical entity commonly known as sleep bruxism (SB). Many pragmatic issues about SB diagnosis and management remain controversial. Therefore, within a critical review of the literature, this article proposes an operational clinical approach for SB diagnosis and management, with a focus on three comorbidities frequently occurring in relation to sleep: obstructive sleep apnea (OSA), gastroesophageal reflux disease (GERD), and insomnia. In the absence of any comorbidities, and if clinically justified, short-term medication and/or splints may be considered. If a comorbid condition is suspected, then the patient should be screened for OSA, GERD, and insomnia. For OSA screening, the Epworth Sleepiness Scale, STOP-Bang, and NoSAS questionnaires are available validated tools. For GERD screening, a positive patient report, whether associated or not with clinical signs and symptoms of heartburn and/or regurgitation, can be tested. For insomnia screening, report of difficulties initiating or maintaining sleep or of early morning awakening more than three times a week may be useful for diagnosis clarification. An adequate clinical approach for comorbid SB requires that both SB and the related comorbid condition be properly assessed and managed. Very often, improvement of SB with treatment of the associated condition will confirm the relationship and establish a more precise diagnosis (ie, secondary SB). Clinicians intending to manage SB should be able to identify these possible clinical interactions, and, if needed, perform an integrative multidimensional approach. Some approaches will benefit from a multidisciplinary approach for achieving therapeutic success. Keywords: gastroesophageal reflux, insomnia, obstructive sleep apnea, sleep bruxism

Aims: To assess the effectiveness of a variety of physical treatments in the management of tension-type headache (TTH) in children. Methods: This review is reported in accordance with the PRISMA guidelines and was registered in the PROSPERO database (CRD42014015290). Randomized and nonrandomized controlled trials that examined the effects of all treatments with a physical component in the management of TTH in children and compared these treatments to a placebo intervention, no intervention, or a controlled comparison intervention were included. The Physiotherapy Evidence Database (PEDro) criteria for bias assessment and the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) Working Group criteria were used to assess the quality of the body of evidence. The outcome measures were pain, functioning, and quality of life. Only RCTs were included in the meta-analyses. Results: An initial search produced 10,464 published articles. Of these, 17 were relevant trials, including 1,815 participants. The overall GRADE rating of the included studies was moderate, and 11 of the 17 studies could be used in the meta-analyses. The effectiveness of physical treatments in terms of a reduction of pain of 50% or more showed a risk ratio (RR) of 2.37 (95% CI: 1.69 to 3.33). Relaxation training was the most evaluated intervention and proved to be significantly effective (RR: 3.00 [95% CI: 1.94 to 4.63]). In children having TTH combined with temporomandibular disorders, occlusal appliances were effective (RR: 2.58 [95% CI: 1.37 to 4.85]). Conclusion: This review supports the use of physical treatments to reduce pain in children with TTH. Keywords: child, headache, meta-analysis, myofascial, pain, systematic review, temporomandibular disorders, therapeutics, therapy, treatment

Entrustable professional activities (EPAs) are a curriculum development and learner assessment tool that ensure a trainee is able to safely translate the skills they have learned during residency into unsupervised clinical practice. Although EPAs are used extensively across various health professions worldwide, dentistry is just beginning to call for their development at both the predoctoral and postgraduate levels. Given the complex, multifactorial nature of orofacial pain disorders and the need for an interdisciplinary approach to management, the specialty of orofacial pain is well suited to embracing EPAs to ensure program graduates are prepared for practice. Therefore, 10 EPAs have been developed in a combined effort from program directors from every CODA-accredited postgraduate orofacial pain residency program. Keywords: competency, entrustable professional activity, EPA, pain education

Aims: To examine the associations of self-reported presence of tinnitus with subtypes of temporomandibular disorders (TMD) as assessed by Axis I of the Diagnostic Criteria for TMD (DC/TMD) and with psychologic characteristics as assessed by Axis II. Methods: This retrospective controlled study included 108 consecutive TMD patients referred to the Tel Aviv University Orofacial Pain Clinic. Each patient received full Axis I and Axis II diagnoses according to the DC/TMD. The patients were asked about currently experiencing tinnitus. Pearson chisquare test and Fisher exact test were used to test the associations between categorical variables. Mann-Whitney test was used to assess differences in continuous variables between categories. A P value .05 was considered statistically significant. Results: Thirty-three (30.6%) TMD patients reported experiencing tinnitus. There was a significantly higher prevalence of myofascial pain with referral (P = .008) and nonspecific physical symptoms (P = .014) among the TMD patients who reported tinnitus. In addition, those patients reported significantly longer pain duration compared to TMD patients without tinnitus (P = .039). Conclusion: This study emphasizes the necessity of assessing both Axes I and II according to the DC/TMD in future studies and supports creating a standardized tinnitus screener tailored to TMD patients for future studies on tinnitus in TMD patients. Keywords: diagnostic criteria for TMD, myofascial pain with referral, nonspecific physical symptoms, temporomandibular disorders, tinnitus

Aims: To examine if the existence of an association between self-reported awake oral behaviors and orofacial pain depends on the belief of patients that these behaviors are harmful to the jaw and to investigate if an additional variable (ie, somatic symptoms, depression, and/or anxiety) indirectly affects the association between the causal attribution belief and the report of awake oral behaviors. Methods: Prior to the first clinical visit, patients referred to a specialized clinic for complaints of orofacial pain and dysfunction completed a digital questionnaire. Data of 329 patients diagnosed with myalgia according to the Diagnostic Criteria for Temporomandibular Disorders (82.4% women; mean ± SD age = 41.9 ± 14.7 years) were analyzed. Results: Causal attribution belief moderated the association between awake oral behaviors and orofacial pain intensity. In addition, the relationship between causal attribution belief and self-reported oral behaviors was partially mediated by the presence of somatic symptoms (8%), depression (9%), and anxiety (16%). Conclusion: Awake oral behaviors were positively associated with orofacial pain, but only under the condition of a strong belief of the patients in causal attribution of these behaviors to the jaw pain complaint. No such association was present in case of a low causal attribution belief. It appeared that, within this patient cohort, the relationship between causal attribution belief and self-reported oral behaviors was (in part) the result of shared psychologic risk factors. Keywords: associations, awake oral behaviours, causal attribution belief, pain-related temporomandibular disorders, psychological factors

Aims: To investigate pain sensitivity in the masseter muscle and index finger in response to acute psychologic stress in healthy participants. Methods: Fifteen healthy women (23.7 ± 2.3 years) participated in two randomized sessions: in the experimental stress session, the Paced Auditory Serial Addition Task (PASAT) was used to induce acute stress, and in the control session, a control task was performed. Salivary cortisol, perceived stress levels, electrical and pressure pain thresholds (PTs), and pain tolerance levels (PTLs) were measured at baseline and after each task. Mixed-model analysis was used to test for significant interaction effects between time and session. Results: An interaction effect between time and session occurred for perceived stress levels (P .001); perceived stress was significantly higher after the experimental task than after the control task (P .01). No interaction effects occurred for salivary cortisol levels, electrical PTs, or pressure PTLs. Although significant interactions did occur for electrical PTL (P .05) and pressure PT (P .001), the simple effects test could not identify significant differences between sessions at any time point. Conclusion: The PASAT evoked significant levels of perceived stress; however, pain sensitivity to mechanical or electrical stimuli was not significantly altered in response to the stress task, and the salivary cortisol levels were not altered in response to the PASAT. These results must be interpreted with caution, and more studies with larger study samples are needed to increase the clinical relevant understanding of the pain mechanisms and psychologic stress. Keywords: analgesia, facial pain, hyperalgesia, pain, stress