Increasing gender differences in the prevalence and chronification of orofacial pain in the population

Implementing Telemedicine During the COVID-19 Pandemic: Disparities in Utilization in an Urban Pain Medicine Practice

Purpose

The COVID-19 pandemic led to a drastic expansion in utilizing telemedicine, circumventing some of the geographical barriers to accessing pain care. However, uncertainties around the impact of telemedicine across various sociodemographic groups still exist, prompting further exploration. Therefore, this study aimed to evaluate the impact of sociodemographic factors in telemedicine utilization during and after the COVID-19 pandemic.

Patients and methods

All outpatient non-procedural visits at the pain medicine division of a large academic institution in the epicenter of the pandemic (New York, USA), between March 2019 and October 2021, were retrospectively included. Sociodemographic data including gender, age, ethnicity/race, postal code, and type of health insurance, across three time periods associated with the COVID-19 pandemic - pre-lockdown (in-office visits only), lockdown (telemedicine visits only) and post-lockdown (offering both in-office and telemedicine visits) - were analyzed and compared.

Results

In total, 12,615 unique patients - The majority being women (58%) - were seen during the whole study period. In the post-lockdown period, telemedicine was utilized by 42% of all patients. Follow-up visits, younger patients, white patients, patients residing further away from the hospital, and privately insured patients were more likely to utilize telemedicine post-lockdown (p <0.05). Older patients, minorities, Manhattan residents, and Medicare/Medicaid recipients, were more likely to use in-office visits post-lockdown (p <0.05).

Conclusion

We identified disparities in the utilization of telemedicine in Pain Medicine, which may be due to socioeconomic factors such as lack of access to reliable internet access, cost of devices, and technological know-how. This emphasizes the need for further studies to better understand the reasons for and barriers to telemedicine use. This could help inform policymaking to safeguard equitable access to telemedicine use for pain care.

DC/TMD Axis I diagnostic subtypes in TMD patients from Confucian heritage cultures: a stratified reporting framework

OBJECTIVES

This study proposed a conceptual framework for reporting Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) Axis I conditions and investigated the prevalence of TMD subtypes/categories in patients from Confucian heritage cultures. Variances in gender, age, and TMD chronicity between Chinese (CN) and Korean (KR) patients were also explored.

MATERIALS AND METHODS

Subjects were recruited from consecutive patients seeking care at two University-based centers in Beijing and Seoul. Eligible patients completed a demographic survey as well as the DC/TMD Symptom Questionnaire and were clinically examined according to the DC/TMD methodology. Axis I diagnoses were subsequently rendered with the DC/TMD algorithms and documented using the stratified reporting framework. Statistical evaluations were performed with chi-square, Mann-Whitney U tests, and logistic regression analysis (α = 0.05).

RESULTS

Data of 2008 TMD patients (mean age 34.8 ± 16.2 years) were appraised. Substantial differences in female-to-male ratio (CN > KR), age (KR > CN), and TMD duration (KR > CN) were observed. Ranked frequencies of the most common Axis I diagnoses were: CN - disc displacements (69.7%) > arthralgia (39.9%) > degenerative joint disease (36.7%); KR - disc displacements (81.0%) > myalgia (60.2%) > arthralgia (56.1%). Concerning TMD categories, notable differences in the prevalence of intra-articular (CN 55.1% > KR 15.4%) and combined (KR 71.8% > CN 33.4%) TMDs were discerned.

CONCLUSIONS

Though culturally similar, the two countries require disparate TMD care planning/prioritization. While TMJ disorders in children/adolescents and young adults should be emphasized in China, the focus in Korea would be on TMD pain in young and middle-aged adults.

CLINICAL RELEVANCE

Besides culture, other variables including socioeconomic, environmental, and psychosocial factors can influence the clinical presentation of TMDs. Chinese and Korean TMD patients exhibited significantly more intra-articular and combined TMDs respectively.

Effectiveness of Physical Therapy Interventions for Temporomandibular Disorders Associated with Tinnitus: A Systematic Review

Temporomandibular disorders (TMDs) refers to different clinical conditions affecting the temporomandibular joints, masticatory muscles, and adjacent structures. Although TMDs signs and symptoms (e.g., pain and limited mouth opening) are common, otological symptoms, such as tinnitus, might also be present. This study aims to summarize the evidence of the effectiveness of physical therapy interventions in individuals with TMDs associated with tinnitus. Randomized controlled trials investigating the effectiveness of physical therapy in individuals of both genders aged 18 or older with TMDs associated with tinnitus were included. The electronic search was performed in the following databases: MEDLINE, EMBASE, CINAHL, PEDro and CENTRAL. A total of four studies were included. All studies showed that physical therapy reduced the intensity of tinnitus, and two trials showed a decrease in the pain intensity caused by TMDs, an increase in the pressure pain thresholds in the masticatory muscles and an improvement of mandibular function. Two studies presented a low risk of bias. Despite a low certainty of the evidence, this review showed that physical therapy reduces the intensity or severity of tinnitus associated with TMDs. Results may support future research on the topic and evidence-based practice by recommending the best physical therapy approach for patients, clinicians, researchers, and health system managers.

Sex-dependent Differences in the Genomic Profile of Lingual Sensory Neurons in Naïve and Tongue-Tumor Bearing Mice

Mechanisms of sex-dependent orofacial pain are widely understudied. A significant gap in knowledge exists about comprehensive regulation of tissue-specific trigeminal sensory neurons in diseased state of both sexes. Using RNA sequencing of FACS sorted retro-labeled sensory neurons innervating tongue tissue, we determined changes in transcriptomic profiles in males and female mice under naïve as well as tongue-tumor bearing conditions Our data revealed the following interesting findings: 1) Tongue tissue of female mice was innervated with higher number of trigeminal neurons compared to males; 2) Naïve female neurons innervating the tongue exclusively expressed immune cell markers such as Csf1R, C1qa and others, that weren't expressed in males. This was validated by Immunohistochemistry. 4) Accordingly, immune cell markers such as Csf1 exclusively sensitized TRPV1 responses in female TG neurons. 3) Male neurons were more tightly regulated than female neurons upon tumor growth and very few differentially expressed genes (DEGs) overlapped between the sexes, 5) Male DEGs contained higher number of transcription factors whereas female DEGs contained higher number of enzymes, cytokines and chemokines. Collectively, this is the first study to characterize the effect of sex as well as of tongue-tumor on global gene expression, pathways and molecular function of tongue-innervating sensory neurons.

Standardized Centella asiatica (ECa 233) extract decreased pain hypersensitivity development in a male mouse model of chronic inflammatory temporomandibular disorder

Chronic inflammatory temporomandibular disorder (TMD) pain has a high prevalence, and available nonspecific treatments have adverse side effects. ECa 233, a standardized Centella asiatica extract, is highly anti-inflammatory and safe. We investigated its therapeutic effects by injecting complete Freund's adjuvant (CFA) into right temporomandibular joint of mice and administering either ibuprofen or ECa 233 (30, 100, and 300 mg/kg) for 28 days. Inflammatory and nociceptive markers, bone density, and pain hypersensitivity were examined. CFA decreased ipsilateral bone density, suggesting inflammation localization, which ipsilaterally caused immediate calcitonin gene-related peptide elevation in the trigeminal ganglia (TG) and trigeminal subnucleus caudalis (TNC), followed by late increase of NaV1.7 in TG and of p-CREB and activation of microglia in TNC. Contralaterally, only p-CREB and activated microglia in TNC showed delayed increase. Pain hypersensitivity, which developed early ipsilaterally, but late contralaterally, was reduced by ibuprofen and ECa 233 (30 or 100 mg/kg). However, ibuprofen and only 100-mg/kg ECa 233 effectively mitigated marker elevation. This suggests 30-mg/kg ECa 233 was antinociceptive, whereas 100-mg/kg ECa 233 was both anti-inflammatory and antinociceptive. ECa 233 may be alternatively and safely used for treating chronic inflammatory TMD pain, showing an inverted U-shaped dose-response relationship with maximal effect at 100 mg/kg.

The Longitudinal Relationship between Jaw Catching/Locking and Pain

Orofacial pain and joint-related dysfunction can negatively affect daily jaw function. A common cause for limitations in jaw movements is joint-related dysfunction such as various forms of catching and locking. However, knowledge is limited regarding the development and natural course of joint-related jaw dysfunction and its relationship to the onset and course of orofacial pain. Therefore, the aim was to evaluate the incidence, prevalence, and gender differences in jaw catching/locking over time and in relation to orofacial pain in the general population. Data from 3 validated screening questions on orofacial pain and jaw catching/locking were collected from all routine dental checkups in the Public Dental Health Services in Västerbotten, Sweden, from 2010 to 2017. Logistic generalized estimating equation was used to account for repeated observations and Poisson regression for incidence analysis. In total, 180,308 individuals (aged 5-104 y) were screened in 525,707 dental checkups. In 2010, based on 37,647 individuals, the prevalence of self-reported catching/locking was higher in women than in men (3.2% vs. 1.5%; odds ratio, 2.11; 95% confidence interval [CI], 1.83-2.43), and this relationship and magnitude remained similar throughout the study period. The annual incidence rate was 1.1% in women and 0.5% in men. Women were at a higher risk than men for reporting both first onset (incidence rate ratio [IRR], 2.29; 95% CI, 2.11-2.49) and persistent (IRR, 2.31; 95% CI, 2.04-2.63) catching/locking. For the onset subcohort (n = 135,801), an independent onset of orofacial pain or jaw catching/locking exclusively was reported by 84.1%, whereas a concurrent onset was reported by 13.4%. Our findings of higher incidence, prevalence, and persistence in women than in men indicate that the gender differences seen for orofacial pain are evident also for jaw catching/locking. The findings also suggest independent onset of self-reported catching/locking and orofacial pain, which reinforces the pathophysiological differences between these conditions.

Clinical signs in the jaw and neck region following whiplash trauma-A 2-year follow-up

BACKGROUND

Pain in the orofacial region is often reported after whiplash trauma. However, prospective studies evaluating clinical signs related to orofacial pain and disability in whiplash populations are rare. The aim of the present study was to evaluate clinical signs related to pain and dysfunction in orofacial and neck regions after whiplash trauma, in a short- and long-term perspective.

METHODS

In total, 84 cases (48 women) diagnosed with neck distortion after a car accident and 116 controls (68 women) were examined within 1 month, and 49 cases (27 women) and 71 controls (41 women) were re-examined 2 years later. Outcome measures were pain on palpation of jaw and neck muscles and maximal jaw opening. Analysis was performed using mixed-models.

RESULTS

Cases and women were at higher risk for pain on palpation of jaw muscles (OR:7.7; p < 0.001 and OR:3.2; p = 0.010 respectively) and neck muscles (OR:12.7; p < 0.001 and OR:2.9; p = 0.020 respectively) but with no significant effect of time. Cases and women also had lower maximal jaw opening (-3.1; p = 0.001 and -3.3; p = 0.001 respectively). There was no significant time effect, but a significant interaction between cases and time (2.2; p = 0.004).

CONCLUSION

Individuals with a whiplash trauma present a higher risk for pain on palpation in jaw and neck muscles both in a short- and long-term perspective, but show normal jaw movements. No time effect suggests that cases do not spontaneously improve nor get worse. Investigating pain on palpation in the jaw and neck muscles after whiplash trauma can identify individuals at risk for developing long-term orofacial pain and dysfunction.

SIGNIFICANCE

Orofacial pain is often reported after whiplash trauma but most previous studies concerning orofacial pain in whiplash populations have been questionnaire studies. Cases with a previous whiplash trauma and women, in general, had higher risk for pain on palpation in the jaw and neck region. Investigating pain on palpation after a whiplash trauma can help to identify individuals at risk of developing long-lasting pain in the orofacial region.

Persistent Orofacial Pain Attendances at General Medical Practitioners

Patients with persistent orofacial pain (POFP) can go through complex care pathways to receive a diagnosis and management, which can negatively affect their pain. This study aimed to describe 44-y trends in attendances at Welsh medical practices for POFP and establish the number of attendances per patient and referrals associated with orofacial pain and factors that may predict whether a patient is referred. A retrospective observational study was completed using the nationwide Secure Anonymised Information Linkage Databank of visits to general medical practices in Wales (UK). Data were extracted using diagnostic codes ("Read codes"). Orofacial and migraine Read codes were extracted between 1974 and 2017. Data were analyzed using descriptive statistics and univariate and multivariable logistic regression. Over the 44-y period, there were 468,827 POFP and migraine diagnostic codes, accounting for 468,137 patient attendances, or 301,832 patients. The overall attendance rate was 4.22 attendances per 1,000 patient-years (95% confidence interval [CI], 4.21-4.23). The attendance rate increased over the study period. Almost one-third of patients (n = 92,192, 30.54%) attended more than once over the study period, and 15.83% attended more than once within a 12-mo period. There were 20,103 referral codes that were associated with 8,183 patients, with over half these patients being referred more than once. Odds of receiving a referral were highest in females (odds ratio [OR], 1.23; 95% CI, 1.17-1.29), in those living in rural locations (OR, 1.17; 95% CI, 1.12-1.22), and in the least deprived quintile (OR, 1.39; 95% CI, 1.29-1.48). Odds also increased with increasing age (OR, 1.03; 95% CI, 1.03-1.03). The increasing attendance may be explained by the increasing incidence of POFP within the population. These patients can attend on a repeated basis, and very few are referred, but when they are, this may occur multiple times; therefore, current care pathways could be improved.

Dietary experiences during fixed orthodontic treatment

Objectives:

Orthodontists generally recommend avoidance of certain foods during fixed appliance (FA) treatment, based on anecdotal information. This study aimed to identify the dietary preferences and experiences of patients undergoing FA treatment as a step toward the preparation of evidence-based dietary guidelines.

Material and Methods:

Questionnaires regarding dietary preferences and experiences of patients undergoing FA treatment were applied to a convenience sample of 38 adolescents (12 M; 26 F). Open-ended responses were summarized and visualized in a world cloud generator. 5-point Likert and Visual Analog Scales (VAS) were used to record the closed-ended responses. Descriptive statistics and multivariate analysis of variance were used to analyze questionnaire findings.

Results:

Lollies, apples, and nuts frequently caused problems with FA. The most frequent reason for avoiding certain types of food was worry about appliance breakage, followed by pain and sensitivity. VAS scores indicated that toffee and caramel scored highest (65.1% F and 54.1% M) for discomfort followed by corn on the cob (64.4% F and 48.7% M) and apples (56.6% F and 55.3% M). VAS scores did not differ significantly between the sexes (P > 0.05). Nearly, a quarter of the sample reported that FA negatively affected their eating behaviors, causing pain and discomfort during eating. No sex differences (P > 0.05) were found for negative experiences with food.

Conclusion:

Dietary preferences and experiences of patients undergoing FA treatment were identified concerning a New Zealand diet profile. A future study with a larger sample size will help formulate evidence-based dietary guidelines during FA treatment.

Antinociceptive and anxiolytic-like effects of Lavandula angustifolia essential oil on rat models of orofacial pain

BACKGROUND

Nociceptive and inflammatory orofacial pain is highly prevalent in the population, which justifies the search for safer analgesics. There is increasing evidence of the analgesic and anxiolytic potential of Lavandula angustifolia essential oil (LAV EO), which may represent, when administered through inhalation, may represent a safer alternative for pain treatment.

OBJECTIVE

to evaluate whether LAV EO has antinociceptive effect in the formalin test, and anti-hyperalgesic and anxiolytic-like effects in rats subjected to a model of orofacial postoperative pain.

METHODOLOGY

Female Wistar rats were exposed to LAV EO (5%) by inhalation for 30 minutes. After exposure, animals were injected with formalin (2.5%, 50 μL) or saline into the hind paw or upper lip and the number of flinches or facial grooming time, respectively, were evaluated. Likewise, on day 3 after intraoral mucosa incision, the animals were exposed to LAV EO and facial mechanical, and heat hyperalgesia were assessed. The influence of LAV EO inhalation on anxiety-like behavior was assessed in operated rats by testing them on the open field (OF) and elevated plus maze (EPM).

RESULTS

LAV EO reduced the phase II of the paw formalin test and both phases of the orofacial formalin test. On day three post-incision, LAV EO reduced heat and mechanical hyperalgesia, from 30 minutes up to three hours, and reduced the anxiety-like behavior in operated rats without causing locomotor deficit.

CONCLUSION

LAV EO inhalation results in antinociceptive and anxiolytic-like effects in orofacial pain models, which encourages further studies on LAV EO indications and effectiveness on orofacial pain conditions.

Continued persistent facial pain despite several surgical interventions in the temporomandibular joint

This article describes a woman in her forties who spontaneously developed facial pain 19 years after double-jaw orthognathic surgery. The focus of her pain was the left side of the face, including the temporomandibular joint (TMJ). Conservative treatment was initiated, including several occlusal splints, in addition to injections with local anesthesia, botulinum toxin, and corticosteroids, with limited effects. Surgical treatments with arthroscopy and discectomy, and ultimately a TMJ prosthesis, improved the patient's joint function but did not reduce pain. The question is whether the degenerated joint was due to progression of the original disease process or to multiple surgical procedures.

Sex Differences in Pain and Its Treatment

Pain is a highly personal experience. Pain is often considered to be a purely neurologic phenomenon, but in actuality, it is a combination of both sensory and emotional experiences. This has sometimes been translated clinically toward a more mechanistic approach to the assessment and treatment of pain instead of one that does not discount pain mechanisms, but also is more inclusive of the need for humanism - considering the individual. In today's medical environment, more than ever before there is a significant amount of attention being paid to educating clinicians to better understand that several physiological, neurophysiological, and psychosocial factors can significantly impact responses to pain. The composition of these factors will be unique to that individual's life narrative, context, sex, and prior life experiences. Thus, the concept that a templated approach to pain assessment and pharmacotherapeutic treatment planning should not be expected to provide optimal patient satisfaction and treatment outcomes in the majority. The hypotheses that there may be sex-based differences in the pain experience in a variety of ways including pain sensitivity, tolerance to pain, threshold at which something becomes painful, and the effectiveness of endogenous pain modulation systems are not new and have been well represented in the literature. This chapter reviews important key findings in the scientific literature with respect to sex-based differences in pain and pain responses to experimentally induced painful stimuli, pain experienced in commonly occurring painful medical conditions, and variations in responses to pain treatments. Possible explanations to account for observed differences or similarities will also be discussed.

A Review on Autophagy in Orofacial Neuropathic Pain

Orofacial neuropathic pain indicates pain caused by a lesion or diseases of the somatosensory nervous system. It is challenging for the clinician to diagnose and manage orofacial neuropathic pain conditions due to the considerable variability between individual clinical presentations and a lack of understanding of the mechanisms underlying the etiology and pathogenesis. In the last few decades, researchers have developed diagnostic criteria, questionnaires, and clinical assessment methods for the diagnosis of orofacial neuropathic pain. Recently, researchers have observed the role of autophagy in neuronal dysfunction as well as in the modulation of neuropathic pain. On this basis, in the present review, we highlight the characteristics, classification, and clinical assessment of orofacial neuropathic pain. Additionally, we introduce autophagy and its potential role in the modulation of orofacial neuropathic pain, along with a brief overview of the pathogenesis, which in future may reveal new possible targets for treating this condition.

Association of climacterium with temporomandibular disorders at the age of 46 years – a cross-sectional study

OBJECTIVE

Hormonal factors have been suggested to contribute to female dominance among subjects with temporomandibular disorders (TMD). Aim of the study was to examine the association of climacteric status with TMD amongst female participants in the Northern Finland Birth Cohort (NFBC) 1966 at 46 years of age.

MATERIAL AND METHODS

Among female subjects in NFBC1966, climacteric status was determined based on menstrual anamnesis and measurement of blood follicle-stimulating hormone (FSH) levels. Women with FSH > 25 IU/L and amenorrhoea > 4 months were defined as climacteric (case group, n = 71); women not diagnosed as climacteric were defined as preclimacteric (control group, n = 656). Differences between cases and controls were evaluated on self-reported TMD pain, clinical TMD signs and TMD diagnoses using modified Diagnostic Criteria for TMD (DC/TMD) protocol. Crosstabulation and logistic regression models were used to analyse differences between cases and controls.

RESULTS

Compared to preclimacteric women, climacteric women had significantly more often pain on palpation in temporomandibular joints (TMJs) (OR = 2.64, 95% CI 1.12-6.21, p= .026) and more crepitus in TMJs (OR = 2.92, 95% CI 1.13-7.56, p= .027). Degenerative joint disease diagnoses were more common in climacteric than preclimacteric women (OR = 2.27, 95% CI 1.05-4.91, p= .037). Differences were statistically significant after adjusting for confounding factors (body mass index (BMI), smoking, parity). No statistically significant differences in self-reported TMD pain were noted between groups.

CONCLUSION

Among females at the age of 46 years, climacterium seems associated with TMD by increasing pain on palpation in TMJs, subjective symptoms, and clinical signs indicating degenerative changes in TMJs when using DC/TMD.

The Chinese version of the Oral Health Impact Profile-14 (OHIP-14) questionnaire among college students: factor structure and measurement invariance across genders

Background

The Oral Health-related Quality of Life (OHRQoL) is a multi-dimensional concept commonly used to examine the impact of health status on quality of life, and the Oral Health Impact Profile-14 (OHIP-14) questionnaire is a good self-assessment tool. This study was designed to investigate the factor structure of the OHIP-14 scale Chinese version, measurement invariance and latent mean differences across genders among college students.

Methods

The online survey was completed by 919 college students. This study used confirmatory factor analysis (CFA) to check the structural models of the OHIP-14 scale, The correlation of each item with the scale total score could test homogeneity, and Cronbach’s alpha (Cronbach’s α) could evaluate internal consistency. Multi-group CFA was used to explore whether the Chinese version of the OHIP-14 scale was used in male and female populations for measurement consistency. T-test compared scores between men and women. Regression analyses were used to evaluate the relationship between age, gender, education, subject, and the score on the OHIP-14 scale.

Results

We found that the 7-factor structure had the best fit index in the sample. According to Cronbach’s α, the overall score of OHIP was 0.958, and Cronbach’s α for 7 factors was: functional limitation was 0.800, physical pain was 0.854, psychological discomfort was 0.902, physical disability was 0.850, psychological disability was 0.768, social disability was 0.862, social handicap was 0.819 and the test–retest reliability interval was 0.723. Multi-group confirmatory factor analysis supported residual measurement invariance across gender. T-test for scores showed that females scored higher significantly than men as did the overall score, in terms of physical pain (p<0.001), physical disability (p<0.001), and psychological disability (p<0.001).

Conclusions

This study found the OHIP-14 Chinese version to be a good tool for assessing the college students' OHRQoL in China, allowing people to conduct self-assessments.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-022-02441-6.

The Role of Mental Health and Behavioral Disorders in the Development of Temporomandibular Disorder: A SWEREG-TMD Nationwide Case-Control Study

Purpose

There is a well-known association between mental and behavioral disorders (MBD) and temporomandibular disorder (TMD), although the association has not been established in population-based samples. This study aimed to investigate this relationship using national population-based registry data.

Patients and Methods

This case-control study used prospectively collected data from Swedish national registries to investigate exposure to MBD and the probability of developing TMD in all Swedish citizens with hospital-diagnosed or surgically treated TMD between 1998 and 2016. Odds ratios were calculated using conditional logistic regression adjusted for educational level, living area, country of birth, musculoskeletal comorbidity, and history of orofacial/neck trauma.

Results

A statistically significant association between MBD and TMD was found for mood affective disorders (OR 1.4), neurotic, stress-related and somatoform disorders (OR 1.7), behavioral syndromes associated with psychological disturbances and physical factors (OR 1.4), disorders of adult personality and behavior (OR 1.4), disorders of psychological development (OR 1.3), behavioral and emotional disorders with onset usually occurring in childhood and adolescence (OR 1.4), and unspecified mental disorder (OR 1.3). The association was stronger for TMD requiring surgery, with the strongest association in patients with disorders of psychological development (OR 2.9). No significant association was found with schizophrenia, schizotypal and delusional disorders, or mental retardation.

Conclusion

The findings indicate an increased probability of TMD among patients with a history of certain MBD diagnoses, and a stronger association with TMD requiring surgery, specifically repeated surgery. This highlights the need for improved preoperative understanding of the impact of MBD on TMD, as TMD and chronic pain itself may have a negative impact on mental health.

Clinical factors affecting depression in patients with painful temporomandibular disorders during the COVID-19 pandemic

Temporomandibular disorders (TMD) are a multifactorial condition associated with both physical and psychological factors. Stress has been known to trigger or worsens TMD. We aimed to investigate whether the novel coronavirus disease-2019 (COVID-19) pandemic aggravates depression in patients with painful TMD, and the factors that affect their level of depression. We included 112 patients with painful TMD (74 females, 38 males; mean age: 35.90 ± 17.60 years; myalgia [n = 38], arthralgia [n = 43], mixed joint-muscle TMD pain [n = 31]). TMD was diagnosed based on the Diagnostic Criteria for TMD Axis I. Physical pain intensity was recorded using the visual analog scale (VAS); psycho-emotional status (depression: Beck Depression Inventory [BDI], anxiety: Beck Anxiety Inventory [BAI], and generalized stress related to COVID19: Global Assessment of Recent Stress [GARS]) was investigated twice (before [BC] and after COVID-19 [AC]). Additionally, factors affecting BDI-AC were investigated. BDI (p < 0.001), BAI (p < 0.001), GARS (p < 0.001), and VAS (p < 0.01) scores were significantly increased at AC than BC. The depression, anxiety, and stress levels were significantly positively correlated, and the AC and BC values of each factor showed a high correlation. In the mixed TMD group, BDI-AC was positively correlated with VAS-AC (p < 0.001). In the multiple regression analysis, clenching habit was the strongest predictor of an increase in the BDI scores from moderate to severe, followed by psychological distress, muscle stiffness, female sex, BAI-AC, and TMJ sounds. COVID-19 has negatively affected the psycho-emotional state of patients with painful TMD, and several clinical factors, including female sex and clenching habits, have influenced depression.

"No One Truly Understands What We Go through and How to Treat It": Lived Experiences with Medical Providers among Patients with Orofacial Pain

Orofacial pain affects 10-15% of adults, yet treatments are limited. The gaps in care are frustrating for both patients and providers and can negatively impact patient-provider interactions. These interactions are key because they impact patient-reported outcomes and satisfaction with care.

PURPOSE

Our study aims to understand the nuanced experiences with medical providers among patients with orofacial pain.

METHODS

In a cross-sectional survey, 260 patients provided written responses describing their experiences with medical providers. Using an inductive-deductive approach to thematic analysis, we identified themes and subthemes and organized them into four domains based on the Patient-Centered Model of Communication.

RESULTS

Patients reported feeling hopeless about treatment options, frustrated with lack of provider knowledge, disappointed in ineffective care, and stigmatized and dismissed by providers. Patients also said they learned to advocate for their health, were grateful for effective care, and felt lucky when providers listened and showed compassion. Patients identified key barriers that interfere with care (e.g., insurance, transportation, limited providers, lack of team coordination).

CONCLUSIONS

Findings can help inform training programs and psychoeducation that target patient-provider communication to improve patient-reported outcomes, the quality of care delivered, and health care utilization and costs.

The TMD-7 as a Brief Measure for Assessing Temporomandibular Disorder

OBJECTIVES

 The aim of this cross-sectional prospective study was to determine the internal consistency of the TMD-7, and compare prevalence of TMD symptoms in an adult population.

MATERIALS AND METHODS

 Upon presenting to the orthodontic screening appointment, a total of 440 subjects (316 females and 124 males) were asked to complete the TMD-7 questionnaire. A total of 108 of the participants were later excluded from the study either due to the duplicate or missing responses. The final sample consisted of data from 332 participants (232 females and 100 males), aged between 18 and 64 (mean age: 42.9 ± 9.0) years.

STATISTICAL ANALYSIS

 Cronbach's α statistics were calculated to assess internal consistency. Comparisons between genders, among age categories, and between subjects with versus without prior orthodontic treatment were performed using Wilcoxon ranks sum and Kruskal-Wallis tests. Comparisons for differences in the individual TMD-7 item ratings were performed using Mantel-Haenszel chi-square tests for ordered categorical responses.

RESULTS

 The calculated Cronbach's α for TMD-7 scale was 0.77. No statistically significant differences were found in the TMD-7 scale score or the individual TMD-7 item ratings between age categories (p = 0.993). Females had significantly higher TMD-7 scale score and higher ratings for headache, pain in jaw, pain in neck, pain in forehead, difficulty opening mouth, and difficulty while eating (p < 0.05). No statistically significant differences were found in the TMD-7 scale score or the individual TMD-7 item ratings between subjects with versus without previous orthodontic treatment (p = 0.075).

CONCLUSION

 The TMD-7 tool has good internal consistency and can be used reliably for assessment of TMD symptoms in adults. The use of this tool revealed no significant differences between age groups or between subjects with or without previous orthodontic treatment. However, a significant female gender predisposition for TMD symptoms in the adulthood was determined.

The Global Need for Easy and Valid Assessment Tools for Orofacial Pain

The World Health Organization recently adopted a historic resolution (WHA74.5) on the urgent need for global oral health improvement. This resolution is particularly relevant in the perspective of the high prevalence of untreated oral diseases. However, one important aspect has been mentioned only in passing, namely that poor oral health often leads to orofacial pain, which is the most common reason for emergency dental visits worldwide. Therefore, an evidence-based decision-making process on oral health should include data related to orofacial pain complaints. To that end, the availability of reliable and valid assessment tools of orofacial pain and related treatment outcomes is essential. INfORM (International Network for Orofacial Pain and Related Disorders Methodology) of the International Association for Dental Research has been one of the driving forces behind the development and implementation of comprehensive sets of tools for such assessments. However, as a prerequisite for the desired global implementation, reliable and valid tools that are also brief, easy to translate, and culturally adaptable need to be further developed and tested. Some of the groundwork to facilitate this process has already been carried out. In addition, a working group within INfORM has developed a short clinical assessment tool for orofacial pain diagnostics that is near completion and will soon be ready for dissemination. Ultimately, reliable and valid orofacial pain assessment is a necessary step toward the development and implementation of appropriate "best buy" interventions that address this major driver of need for oral health care worldwide.

The Role of Pain Inflexibility and Acceptance among Headache and Temporomandibular Disorders Patients

Temporomandibular disorders (TMD) and headache are complex. This study aims to assess the association between TMD, headache, and psychological dimensions such as psychological inflexibility and pain acceptance. The sample consisted of 120 participants following a non-probabilistic convenience sampling strategy through a direct invitation to the patients attending our facilities and their relatives (n = 61 diagnosed with headache, n = 34 diagnosed with TMD-headache, n = 25 control group). Diagnostic Criteria for Temporomandibular Disorders (DC-TMD), International Classification of Headache Disorders (ICHD-3 beta version), Chronic Pain Acceptance Questionnaire (CPAQ-8), and Psychological Inflexibility in Pain Scale (PIPS) were used as assessment tools. One-way ANOVA, multiple regression analysis (MRA), and the Johnson-Neyman approach were run by IBM SPSS, version 27 (IBM^® Company, Chicago, IL, USA). The significance level was 0.05. One third of our sample presented with headache with TMD. Females were predominant. Males with headache, no systemic disease, less pain severity but higher frequency, living longer with the disease and having sensitive changes, showed higher pain acceptance. When headache occurs with TMD, women with higher education, no headache family history, less pain, and no motor changes showed higher pain acceptance. Patients with both conditions are more liable to have chronic pain and pain inflexibility. Pain intensity and willingness explain 50% of the psychological inflexibility in the headache group. In our sample, individuals suffering from both conditions show greater pain inflexibility, implicating more vivid suffering experiences, leading to altered daily decisions and actions. However, further studies are needed to highlight this possible association.

Fear of Movement and Catastrophizing in Participants with Temporomandibular Disorders

AIMS

To assess differences in catastrophizing and kinesiophobia in relation to areas of pain and somatic symptoms among participants with temporomandibular disorders (TMDs) and controls.

METHODS

In total, 401 participants (333 women, 68 men, mean age: 45.8 years) in the TMJ Impact Project were examined in accordance with the Diagnostic Criteria for TMD, including clinical examination (Axis I) and psychosocial assessment (Axis II) augmented with imaging of the temporomandibular joint (TMJ). Of these, 218 participants had a painful TMD pain diagnosis, 63 had a nonpainful TMD diagnosis, and 111 had no TMD. Nine participants had missing data. Participants completed the Pain Catastrophizing Scale, Tampa Scale for Kinesiophobia, Areas of Pain figure, and the Patient Health Questionnaire-15 for assessing somatic symptoms.

RESULTS

Compared to controls, participants with TMD pain showed higher levels of catastrophizing (P = .017), kinesiophobia (P < .001), areas of pain (P < .001), and somatic symptoms (P < .001). Participants with nonpainful TMD showed a higher level of kinesiophobia (P < .001) than controls. There was a positive correlation between catastrophizing and kinesiophobia for participants with TMD pain (r = 0.33, P < .001) and nonpainful TMD (r = 0.42, P < .001).

DISCUSSION

The results suggest more fear of movement, as well as an association between catastrophizing and fear of movement, in participants with TMD pain and in participants with nonpainful TMD compared to controls. Assessment and management of fear of movement as well as catastrophizing may be useful as part of individualized treatment strategies for patients with TMD.

Sociodemographic trends in a UK temporomandibular joint disorder clinic

Introduction Temporomandibular disorders (TMD) are a common source of facial pain, resulting from an interaction of biopsychosocial factors. However, social risk factors related to TMD have been researched very little, particularly in patients attending a tertiary care service.Aims To review sociodemographic trends among patients referred to a UK tertiary TMD clinic for specialist management. To provide an insight into the sociodemographic risk factors associated with TMD in patients referred for specialist input and to discuss the surrounding literature.Methods Retrospective review of notes of patients referred to a UK tertiary TMD clinic. Trends in areas of deprivation from which patients came from were quantified into deciles using the English Multiple Indices of Deprivation.Results The mean age of patients was 41.1 years, with women being overrepresented compared to men. Most patients were referred by their general dental practitioner, although a variety of secondary care specialties also referred to this service. A disproportionate number of patients came from the highest decile of deprivation, a trend seen throughout the entire sample and in patients seen by dental professionals specifically. There was no apparent association between this and longer symptom duration.Conclusion Women and those from areas with the highest levels of deprivation were overrepresented in this tertiary clinic setting. Dentists should maintain an awareness of the risk factors for TMD development as well as those which may complicate its management in cases requiring specialist input.

The impact of gender of the examiner on orofacial pain perception and pain reporting among healthy volunteers

Objectives

Pain on palpation of jaw muscles is a commonly used diagnostic criterion when examining patients with orofacial pain. It is not known, however, if pain reports are affected by the gender of the examiner. Our aim was to investigate if pressure pain threshold (PPT), pressure pain tolerance (PTol), and pain intensity assessed over the masseter muscles in healthy individuals are affected by the gender of the examiner.

Materials and methods

Healthy, pain-free individuals were recruited on a voluntary basis. PPT and PTol were assessed using pressure algometry. At the PTol level, participants also rated pain intensity on a 0–10 numeric rating scale. Assessments of PPT and PTol were conducted with six repeated measurements performed twice, separately by one female and one male examiner, on each participant.

Results

In total, 84 participants (43 women; median age 24, IQR 6) were included. With a female examiner, women reported higher pain intensity than men (Mann Whitney U, p = 0.005). In the multivariable analysis, significantly higher PTol was predicted by male examiner. Also, a higher ratio between PTol and reported pain intensity was predicted by male examiner.

Conclusions

The gender of the examiner influences pain reporting and perception in an experimental setting. This effect on pain perception related to gender of the examiner is probably related to normative gender behaviors rather than to biological alterations within the examined individual.

Clinical relevance

In clinical and experimental settings, gender of the examiner may affect not only pain perception but also pain reporting, with potential implications for diagnostics in patients with pain.

Effects of Warm Needle Acupuncture on Temporomandibular Joint Disorders: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Temporomandibular joint disorders (TMDs) are a common and prevalent disease with main symptoms of pain, joint sounds, and mandibular movement disorders, which seriously affects the mental health and quality of life of the sufferers. In recent years, there have been an increasing number of studies utilizing warm needle acupuncture (WNA) for the treatment of TMD, and the quality of the studies has gradually improved. However, evidence from evidence-based medicine is lacking. This study aims to use a systematic review and meta-analysis method to understand the efficacy of WNA for the treatment of TMD. Methods and Analysis. We searched randomized controlled trials (RCTs) of WNA for the treatment of TMD from 9 electronic databases, including 5 English databases (PubMed, EMBASE, Cochrane Library, Web of Science, and MEDLINE) and 4 Chinese databases (Chinese National Knowledge Infrastructure (CNKI), Chinese VIP Information, Wanfang Database, and Chinese Biomedical Literature Database (CBM)) from their inception to May 2021. The included RCTs compared WNA with acupuncture, electroacupuncture, pharmacological therapy, or other therapies. And outcome indicators such as total effective rate and cure rate were assessed. All analyses were conducted using RevMan software V5.3 and Stata16. Measurement count data used the relative risk (RR) as the efficacy statistic, and each effect size was given its point estimate value and 95% confidence interval (CI).

RESULTS

The meta-analysis included 10 studies with a total of 670 patients, which included 340 patients in the experimental group and 330 patients in the control group. The data in this review showed that WNA is superior to treatments such as acupuncture alone, acupuncture therapy combined with TDP, drug therapy, and ultrasonic therapy in terms of effective rate (RR = 1.20; 95% CI, 1.06 to 1.35; and P = 0.003) and cure rate (RR = 1.82; 95% CI, 1.46 to 2.28; and P < 0.00001) for the treatment of TMD.

CONCLUSIONS

This systematic review and meta-analysis provides new evidence for the effectiveness of WNA for the treatment of TMD. However, the above conclusions need to be further verified by multicenter prospective studies of larger samples and higher-quality RCTs. Protocol registration number: INPLASY202160030.

A Multidisciplinary Approach to Simultaneously Monitoring Real-Time Neuronal Activity and Pain Behaviors During Optogenetic Stimulation of Brain Neurons in Freely Moving Mice

Background

Highlighted by the current opioid epidemic, identifying novel therapies to treat chronic trigeminal neuropathic pain is a critical need. To develop these treatments, it is necessary to have viable targets in the brain to act on. Historically, neural tracing studies have been extremely useful in determining connections between brain areas but do not provide information about the functionality of these connections. Combining optogenetics and behavioral observation allows researchers to determine whether a particular brain area is involved in the regulation of such behavior. The addition of multi-channel electrophysiological recording provides information on real-time neuronal activity in the specific neuronal pathway.

Methods

Male C57/BL/6J mice (8-week-old) underwent either chronic constriction injury of infraorbital nerve (CCI-ION) or a sham surgery and were injected with either channelrhodopsin (ChR2) or a control virus in the hypothalamic A11 nucleus. Two weeks after CCI-ION, they were tested in real-time place preference (RTPP), while neuronal activity in the spinal trigeminal nucleus caudalis (Sp5C) was recorded.

Results

Optogenetic excitation of the A11 neurons results in more time spent in the stimulation chamber during RTPP testing. Additionally, stimulation of the A11 results in a greater number of neuronal activity increase in the Sp5C in animals with the injection of AAV carrying ChR2 compared to animals injected with a control virus or that underwent a sham surgery.

Conclusion

In vivo multi-channel electrophysiological recording, optogenetic stimulation, and behavioral observation can be combined in a mouse model of chronic trigeminal neuropathic pain to validate brain areas involved in the modulation of such pain.

Unsupervised Machine Learning Identified Distinct Population Clusters Based on Symptoms of Oral Pain, Psychological Distress, and Sleep Problems

Objectives:

The aims of this study were to explore the use of unsupervised machine learning in clustering the population based on reports of oral pain, psychological distress, and sleep problems and to compare demographic and socio-economic characteristics as well as levels of functional domains (work, social, and leisure) between clusters.

Materials and Methods:

In this cross-sectional study, a total of 1613 participants from the National Health and Nutrition Examination Survey in 2017–2018 were analyzed. Five variables, including oral pain, depression, anxiety, sleep apnea, and excessive daytime sleepiness, were selected for cluster analysis using the k-medoids clustering algorithm. The distribution of categorical variables between clusters was assessed using χ² test. One-way analysis of variance and Kruskal–Wallis H test were used to compare numerical variables as appropriate.

Results:

Five distinct clusters were identified: healthy, norm, anxiety, apnea-comorbid, and pain-comorbid. The apnea-comorbid cluster had mean age of 59 years and higher proportion of men. The pain-comorbid cluster had mean age of 56 years and higher proportion of women. Whites constituted a majority of both comorbid clusters. The pain-comorbid cluster demonstrated the least percentage of individuals with college degree, the lowest income, and significant impairment in all functional domains.

Conclusion:

Through the use of unsupervised machine learning, the clusters with comorbidity of oral pain, psychological distress, and sleep problems have emerged. Major characteristics of the comorbid clusters included mean age below 60 years, White, and low levels of education and income. Functional domains were significantly impaired. The comorbid clusters thus call for public health intervention.

Even mild catastrophic thinking is related to pain intensity in individuals with painful temporomandibular disorders

AIMS

Temporomandibular disorders (TMD) are often associated with psychological comorbidities. One such comorbidity is pain catastrophising, that is, exaggeration of negative consequences of a painful event. The aim was to investigate catastrophising in individuals with painful TMD compared to controls and the association between catastrophising and pain intensity, number of pain sites and functional limitations.

METHODS

A community-based sample of 110 individuals (83 women; 20-69 yrs) with painful TMDs (myalgia/arthralgia as per Diagnostic Criteria for TMD) and 190 age- and gender-matched controls (119 women; 20-69 yrs) from the Public Dental services in Västerbotten, Sweden, participated. Associations between catastrophising and functional jaw limitations, respectively, and painful TMD were evaluated with ordinal regression adjusted for the effect of gender and age. Associations (Spearman's correlation) of the Pain catastrophising Scale (PCS) with Jaw Functional Limitation Scale (JFLS-20), pain site number (whole-body pain map), and characteristic pain intensity (CPI) and intergroup comparisons (Mann-Whitney U test) of these variables were also calculated.

RESULTS

Levels of catastrophising were associated with TMD pain (OR 1.6, 95%CI 1.1-2.6). Among individuals with painful TMD, catastrophising was correlated to pain intensity (r=0.458, p<0.01) and functional limitations (r=0.294-0.321, p≤0.002), but not to number of pain sites.

CONCLUSION

Compared to controls, community-based individuals with painful TMD demonstrated higher levels of pain catastrophising, and this catastrophising was associated with increased pain intensity and jaw dysfunction. The relatively low scores of pain catastrophising suggest that even mild catastrophic thinking is associated with pain perception and jaw function, and should be considered in patient management.

DEEP Study: Utility of the multidimensional pain inventory in persistent oro-facial pain

BACKGROUND

Persistent oro-facial pain (POFP) is disabling, and patients' treatment outcomes are difficult to predict; psychosocial factors play a role. The West Haven-Yale Multidimensional Pain Inventory (MPI) is a self-report measure, which to our knowledge, has not been studied across primary and secondary care in heterogeneous POFP.

OBJECTIVE

Assess the MPI's ability to predict clinical outcome in POFP patients across primary and secondary care settings receiving usual care.

METHODS

About 146 patients receiving usual care for POFP were recruited from primary and secondary care medical and dental practices in north-east England. Participants completed the MPI (v3) and Graded Chronic Pain Scale (GCPS) at recruitment, and after 6, 12, 18 and 24 months. The Patient Health Questionnaire-4 (PHQ-4) was completed at recruitment, 12, and 24 months. 'Good' and 'poor' outcome status was assigned to participants based on their mode dichotomised GCPS score across timepoints. Logistic regression was used with overall GCPS outcome (good/poor) as the dependent variable and MPI subscale scores, demographic variables, and PHQ-4 scores as predictors.

RESULTS

110 participants had a 'good', and 36 had a 'poor' outcome. In the 'poor' outcome group, age, mean income, and life control scores were lower; deprivation, months in pain, PHQ-4, pain severity, interference, and affective distress scores were higher. In the 'good' group, MPI scores improved over time. Interference was the only consistent predictor of 'poor' outcome in the logistic regression model (OR: 1.14-1.98, p < 0.05).

CONCLUSION

The MPI interference subscale may help to identify patients with POFP who are likely to have consistent pain-related disability over time; it may therefore be useful clinically to identify patients likely to need early intervention.

Profiling of Patients with Temporomandibular Disorders: Experience of One Tertiary Care Center

Objectives

The aim of this study was to assess typical and most prevalent characteristics of patients suffering from temporomandibular disorders (TMD) by a retrospective assessment of their medical records.

Material and Methods

Demographic data and data on the characteristics of TMD were collected from the existing medical documentation of 304 TMD patients (250 females and 54 males) who had been referred to the Department of Dentistry, Clinical Hospital Center Zagreb from October 2016 to October 2020 due to temporomandibular pain. For the purpose of analysis, three age groups were formed: i) "children and adolescents" (up to 19 years of age); ii) "middle age" (from 20 to 50 years of age); iii) "older age" (>50 year- olds). A two-step cluster analysis was performed with the aim of classifying TMD patients into homogenous groups.

Results

The mean age of patients whose data were included in the study was 33.8 ± 16.66, with a significantly higher age in the group of women (p<0.001). Most of the patients had chronic pain (67.4%), with the ratio in favor of chronic patients being significantly higher in women than in men (p=0.001). Data on parafunctional behavior were confirmed in 14.5% of patients. Data on the onset of symptoms during/just after orthodontic treatment were present in 14.5% of patients. Data on spontaneous pain, assessed with a visual analogue scale, were recorded in 87 patients, with a mean of 6.14 ± 1.79 and with the highest pain in the "older age" group. Physical therapy was the most common therapeutic modality (56.3%) followed by an occlusal splint (40.5%). The analysis revealed 5 different clusters in the TMD patient data set.

Conclusions

Our results are largely in line with current epidemiological knowledge on TMD. Women predominated in all age groups and most of the patients experienced chronic pain. Classifying patients into homogeneous groups using the clustering method could provide better identification of subgroups of conditions that mainly occur together in these patients, thus providing the basis for more specific management.

Altered trigeminal pain processing on brainstem level in persistent idiopathic facial pain

ABSTRACT

Persistent idiopathic facial pain (PIFP) is a poorly understood chronic pain syndrome of the face, formerly known as atypical facial pain. It is characterized by a constant painful sensation without neurological abnormalities and without clinically objectifiable cause. Similarities to neuropathic pain conditions have been discussed and are currently thought to be relevant for the pathophysiology of this disease. In this study, we aim to characterize the trigeminal pain processing in PIFP using functional magnetic resonance imaging of the brainstem. Twenty-five patients suffering from PIFP and 25 healthy controls underwent a standardized and well-established paradigm of painful stimulation of the trigeminal nerve using gaseous ammonia. Functional images were acquired within a 3T magnetic resonance imaging scanner using an optimized protocol for high-resolution echo planar brainstem imaging. Patients with PIFP show exclusively a stronger activation to painful stimulation in the spinal trigeminal nucleus when contrasted against healthy controls. Our data suggest that abnormal central pain processing plays a role in the pathophysiology of PIFP. An integration of these findings into neuropathic pain models might help to gain a better general understanding of the pathophysiology of PIFP.

Knee orthopedics as a template for the temporomandibular joint

Although the knee joint and temporomandibular joint (TMJ) experience similar incidence of cartilage ailments, the knee orthopedics field has greater funding and more effective end-stage treatment options. Translational research has resulted in the development of tissue-engineered products for knee cartilage repair, but the same is not true for TMJ cartilages. Here, we examine the anatomy and pathology of the joints, compare current treatments and products for cartilage afflictions, and explore ways to accelerate the TMJ field. We examine disparities, such as a 6-fold higher article count and 2,000-fold higher total joint replacement frequency in the knee compared to the TMJ, despite similarities in osteoarthritis incidence. Using knee orthopedics as a template, basic and translational research will drive the development and implementation of clinical products for the TMJ. With more funding opportunities, training programs, and federal guidance, millions of people afflicted with TMJ disorders could benefit from novel, life-changing therapeutics.

Transient Receptor Potential (TRP) Ion Channels in Orofacial Pain

Orofacial pain, including temporomandibular joint disorders pain, trigeminal neuralgia, dental pain, and debilitating headaches, affects millions of Americans each year with significant population health impact. Despite the existence of a large body of information on the subject, the molecular underpinnings of orofacial pain remain elusive. Two decades of research has identified that transient receptor potential (TRP) ion channels play a crucial role in pathological pain. A number of TRP ion channels are clearly expressed in the trigeminal sensory system and have critical functions in the transduction and pathogenesis of orofacial pain. Although there are many similarities, the orofacial sensory system shows some distinct peripheral and central pain processing and different sensitivities from the spinal sensory system. Relative to the extensive review on TRPs in spinally-mediated pain, the summary of TRPs in trigeminally-mediated pain has not been well-documented. This review focuses on the current experimental evidence involving TRP ion channels, particularly TRPV1, TRPA1, TRPV4, and TRPM8 in orofacial pain, and discusses their possible cellular and molecular mechanisms.

Prevalence of temporomandibular disorder in adult patients with chronic pain

Objectives

Chronic pain patients often suffer in multiple locations. In health care, examinations of bodily pain usually do not include questions about temporomandibular disorders (TMD); hence TMD symptoms and potential comorbidities are not regularly assessed. Therefore, the primary aim was to evaluate the prevalence of TMD in patients referred to a pain rehabilitation clinic, and the secondary aim was to evaluate possible factors associated with TMD symptoms.

Methods

Consecutive chronic pain patients referred to the Pain Rehabilitation Clinic at the Umeå University Hospital in Sweden were included. TMD symptoms were assessed using three valid screening questions – 3Q/TMD. Pain sites, emotional distress, kinesiophobia, and demographics were obtained from the Swedish Quality Registry for Pain Rehabilitation.

Results

In total, 188 (144 women) chronic pain patients (mean age 41.8 years) were included. Of these, 123 (96 women) answered affirmatively to at least one of the 3Q/TMD. The relative risk of TMD symptoms among the patients with chronic pain, in comparison to the general population, was 7.1 (95% CI 5.9–8.4). Age was the only independent variable associated with TMD among the patients (p = 0.018).

Conclusions

The prevalence of TMD symptoms was higher in a chronic pain population compared to the general population. The 3Q/TMD questionnaire could be a suitable screening tool at pain rehabilitation clinics to identify patients for further examination of involvement of pain in the trigeminal region. Our results reinforce the clinical importance of paying attention to concurrent widespread pain and local TMD symptoms.