Temporomandibular Disorders and Facial Pain: A Psychophysiological Perspective

This article presents a psychophysiological perspective on temporomandibular muscle and joint disorders (TMJD) and facial pain. After a brief introduction to TMJD, the article presents data, largely derived from work carried out in my laboratory, that address four questions: (1) What are the consequences of parafunctional activities? (2) Do TMJD patients engage in parafunctional activities? (3) Why are TMJD patients unaware of these activities? and (4) What are the implications of these findings for treatment? The findings suggest that low-level parafunctions increase pain in otherwise pain-free individuals and can produce symptoms sufficiently severe to meet the diagnostic criteria for TMJD diagnoses of myofascial pain and/or arthralgia. Patients with certain forms of TMJD report very high levels of parafunctional tooth contact. Their lack of awareness of these behaviors may arise from uncertain definitions of the term “clenching”, from proprioceptive deficits, or from the presence of adjunctive behaviors. Preliminary work shows that reduction in tooth contact via habit reversal techniques may be a promising mechanism for reducing pain in these patients.     

Comparison of Habit Reversal and a Behaviorally-Modified Dental Treatment for Temporomandibular Disorders: A Pilot Investigation

This study tested the hypothesis that a habit reversal program emphasizing awareness and reduction of masticatory muscle activity would significantly reduce pain in patients diagnosed with chronic temporomandibular disorder (TMD) and would be a competitive alternative to a behaviorally-modified dental intervention. Eight individuals diagnosed with TMD were randomly assigned to a splint therapy or habit reversal group. Patients in the splint group received an interocclusal appliance (splint) fabricated from acrylic and were instructed to wear the splint day and night up to a maximum of 20 h per day. Patients in the habit reversal group were given a pager and instructed to check tooth position and masticatory muscle tension when paged. Paging occurred approximately once every 2 h during the day, but not at night. Both groups were instructed to avoid tooth contact and relax the masticatory muscles during the 4 weeks of active treatment. Outcome data were collected at 1 month and 1 year post-treatment intervals. Pain decreased significantly for both groups and did not differ between groups. Habit reversal may be as effective as a behaviorally-modified splint therapy for TMD-related pain.     

Influence of a Scheduled-Waiting Task on EMG Reactivity and Oral Habits Among Facial Pain Patients and No-Pain Controls

Recent research has strongly implicated the role of psychological stress in the development of temporomandibular disorders (TMD). It is widely reported that oral habits (e.g., teeth grinding) probably provide a behavioral link between stress and the development of TMD symptomatology. Extrapolation of research in the field of adjunctive behavior to the TMD disorders suggests that oral behaviors may develop conjointly with fixed-time (FT) stimulus presentation. The current experiment extended previous research examining this possibility by assessing the influence of experimental stress on masseter EMG and oral habits among persons who met broadband criteria for TMD and no-pain controls. Oral habit activity was assessed via self-report questionnaire whereas masseter muscle activity was measured continuously via electromyography across four phases (Adaptation, Free-Play, Scheduled-Play, Recovery). The Scheduled-Play phase was designed as a stress-reactivity task that included an FT schedule. Results indicated that, consistent with the stress-reactivity model, the Scheduled-Play phase resulted in a significant increase in masseter EMG levels relative to Free-Play and Adaptation, and that this effect was significantly larger for the TMD group relative to controls. The results suggest an adjunctive behavior effect although the effect was not specific to those with facial pain. Oral habit data showed a significant phase effect with oral habits that was significantly higher during the Scheduled-Play phase relative to Adaptation. The findings are the impetus for further study regarding the mechanisms whereby oral habits are developed and maintained despite their painful consequences.     

Awareness of physiological responding under stress and nonstress conditions in temporomandibular disorders

To test the hypothesis that individuals with temporomandibular disorders (TMD) have deficits in proprioceptive awareness, 20 TMD patients were compared with 20 nonpain individuals matched to the TMD patients on age and gender. Left and right frontalis, masseter, and temporalis were monitored, as were forearm extensor, heart rate, and skin conductance while the participants viewed a nonstressful film segment. Following the film segment, participants provided self-reports of these physiological responses. This sequence was repeated for a second, stressful film segment and for a third, non-stressful film segment. Correlations between physiological activity and self-report were used as measures of proprioceptive awareness. The results indicated that TMD subjects were most accurate in their awareness of facial muscle activity during the stress condition and least accurate in the two nonstress periods. Control subjects increased their accuracy of awareness at each time period, showing significantly greater accuracy than the TMD group in the last, nonstress period. TMD subjects more accurately perceived activity of the nonfacial muscle variables in the two nonstress periods than during the stress period. These findings may provide a mechanism for understanding clinical observations showing that TMD patients with myofascial pain engage in high levels of parafunctional oral activity without awareness.Portions of this study were supported by the Weldon Spring Foundation and by a grant from the National Institute of Dental Research (DE 11017). I thank Drs. Ernest G. Glass and Edward Mosby for their assistance in identifying patients. I also thank Natalie Beltgens, Stella Brown, Linda Coates, Elbert Darden, Ben Javid, and Susan Sherrick for their assistance in recruiting nonpain participants and in helping carry out this study.     

EMG Reactivity and Oral Habits Among Facial Pain Patients in a Scheduled-Waiting Competitive Task

For individuals with temporomandibular disorder (TMD) it has been theorized that stressful events trigger oral habits (e.g., teeth grinding), thereby increasing masticatory muscle tension and subsequent pain. Recent research involving adjunctive behaviors found an increase in masseter surface EMG (sEMG) and oral habits when students with TMD symptomatology were placed on a fixed-time reinforcement schedule. The current study used a treatment-seeking community sample with TMD symptomatology in a competitive task designed to be a more naturalistic Fixed Time task. The experiment consisted of Adaptation, Free-Play, Scheduled-Play, and Recovery phases. During the Scheduled-Play phase participants played, and waited to play, an electronic poker game. Results indicated that masseter muscle tension in the Scheduled-Play phase was significantly higher (p<.001) than in any other phase. Moreover, during the Scheduled-Play phase masseter sEMG was higher (p#60;.001) when participants waited to play. Self-reported oral habits and overall affect were significantly higher (p's<.05) in the Free-Play and Scheduled-Play phases relative to Adaptation and Recovery. The observation that masseter sEMG was elevated during the Scheduled-Play phase relative to all other phases, and within the Scheduled-Play phase sEMG was highest while waiting, suggests that adjunctive oral habits may lead to TMD symptomatology.     

Malocclusion trait and the parafunctional effect among young female school students

Extraneous activities of either the mouth, tongue or the jaw comprise the oral parafunctional habits of the stomatognathic system. This denominated habit is expressed through bruxism, digit sucking, nail biting to name a few, have led to hypothesizing the possible relationship of evolution of occluso-facial abnormalities such as malocclusion thereby hindering the conventional developmental process. Hence, the present study aimed to determine the prevalence and the possible relationship of parafunctional oral habits with the types of malocclusions among 12–16 years old females in Jeddah, Saudi Arabia. This cross-sectional study was conducted through questionnaire and clinical examinations, where the sagittal abnormalities within a randomly selected 672 participants who met the eligibility criteria were tabulated and analyzed. A positive history of the presence of parafunctional habit was recorded among all the participants with nasal and mouth breathing [46.6%], nail biting [39.6%] being predominant. 36.4% presented with significantly higher prevalence of bi-maxillary protrusion in mouth breathers while 17.1% with moderate overbite in participants with nail biting habit. Therefore, within the limitations of the present study, the findings do support the literature on the prevalence and the possible association of these habits with the malocclusion development thereby emphasizing on the importance of early recognition, management and prevention of them.     

Analysis of Trigger Factors in Episodic Migraineurs Using a Smartphone Headache Diary Applications

Background

Various stimuli can trigger migraines in susceptible individuals. We examined migraine trigger factors by using a smartphone headache diary application.

Method

Episodic migraineurs who agreed to participate in our study downloaded smartphone headache diary application, which was designed to capture the details regarding headache trigger factors and characteristics for 3 months. The participants were asked to access the smartphone headache diary application daily and to confirm the presence of a headache and input the types of trigger factors.

Results

Sixty-two participants kept diary entries until the end of the study. The diary data for 4,579 days were analyzed. In this data set, 1,099 headache days (336 migraines, 763 non-migraine headaches) were recorded; of these, 772 headache events had with trigger factors, and 327 events did not have trigger factors. The common trigger factors that were present on headache days included stress, fatigue, sleep deprivation, hormonal changes, and weather changes. The likelihood of a headache trigger was 57.7% for stress, 55.1% for sleep deprivation, 48.5% for fatigue, and 46.5% for any trigger. The headaches with trigger factors were associated with greater pain intensity (p<0.001), headache-related disability (p<0.001), abortive medication use (p = 0.02), and the proportion of migraine (p < 0.001), relative to those without trigger factors. Traveling (odd ratios [OR]: 6.4), hormonal changes (OR: 3.5), noise (OR: 2.8), alcohol (OR: 2.5), overeating (OR: 2.4), and stress (OR:1.8) were significantly associated with migraines compared to non-migraine headaches. The headaches that were associated with hormonal changes or noise were more often migraines, regardless of the preventive medication. The headaches due to stress, overeating, alcohol, and traveling were more often migraines without preventive medication, but it was not evident with preventive medication.

Conclusion

Smartphone headache diary application is an effective tool to assess migraine trigger factors. The headaches with trigger factors had greater severity or migraine features. The type of triggers and the presence of preventive medication influenced the headache characteristics; hence, an investigation of trigger factors would be helpful in understanding migraine occurrences.     

Headaches in Multiple Sclerosis Patients Might Imply an Inflammatorial Process

Recent studies on Multiple Sclerosis (MS) pathology mention the involvement of “tertiary B cell follicles” in MS pathogenesis. This inflammatory process, which occurs with interindividually great variance, might be a link between MS pathology and headaches. The aim of this study was to detect the prevalence of headaches and of subtypes of headaches (migraine, cluster, tension-type headache [TTH]) in an unselected MS collective and to compile possibly influencing factors. Unselected MS patients (n = 180) with and without headache were examined by a semi-structured interview using a questionnaire about headache, depression and the health status. Additionally clinical MS data (expanded disability state score [EDSS], MS course, medication, disease duration) were gathered. N = 98 MS patients (55.4%) reported headaches in the previous 4 weeks. We subsequently grouped headache patients according to the IHS criteria and detected 16 (16.3%) MS patients suffering from migraine (migraine with aura: 2 [2%]; migraine without aura: 14 [14.3%]), 23 (23.5%) suffering from TTH and none with a cluster headache. Thus, headaches of 59 (60.2%) MS patients remained unclassified. When comparing MS patients with and without headaches significant differences in age, gender, MS course, physical functioning, pain and social functioning occurred. MS patients with headaches were significantly younger of age (p = 0.001), female (p = 0.001) and reported more often of a clinically isolated syndrome (CIS) and relapsing/remitting MS (RRMS) instead of secondary chronic progressive MS (SCP). EDSS was significantly lower in MS patients suffering from headaches compared to the MS patients without headaches (p = 0.001). In conclusion headache in MS patients is a relevant symptom, especially in early stages of the MS disease. Especially unclassified headache seems to represent an important symptom in MS course and requires increased attention.     

Migraine: Intelligence,Social Class,and Familial Prevalence

Groups of individuals with headache, unilateral headache, and migraine, and a fourth group who had not had a headache in the previous year, were identified by questionnaire from a random sample of adults in the general population. Intelligence and social class were assessed in about 400 individuals. There was no evidence that individuals with migraine were more intelligent or of higher social class. There was, however, a suggestion that the more intelligent individuals with migraine, and those in social classes I and II, were more likely to consult a doctor for their headaches. This trend might explain the origin of the hypotheses associating migraine with intelligence and with social class.Random samples of individuals with migraine with headache and without headache in the previous year were the probands for a family study. There were 524 first-degree relatives over 21 years of age who lived in South Wales. Headache histories, obtained “blindly” from over 99% of these relatives with a standard questionnaire, were classified as migraine, possible migraine, headache, or without headache in the previous year. The prevalence of migraine in the families of the migrainous probands was nearly twice as high as the prevalence in the other families, but this difference was not statistically significant. It is suggested that family history should not be included in the definition of migraine and that heredity is much less important in migraine than is usually supposed.     

Effectiveness of two physical therapy interventions, relative to dental treatment in individuals with bruxism: study protocol of a randomized clinical trial

Background

Bruxism is a parafunctional habit characterized by grinding and/or clenching of the teeth. It may happen while awake (awake bruxism) or while sleeping (sleep bruxism). In adults, the prevalence is 20% for the awake bruxism and 8% for the sleep bruxism. Peripheral, central, and psychosocial factors influence the disorder, which may predispose to pain in the masticatory muscles and neck, headache, decreased pain thresholds in the masticatory and cervical muscles, limitation mandibular range of motion, sleep disorders, stress, anxiety, depression, and overall impairment of oral health. The aim of this study is to compare two distinct physical therapy interventions with dental treatment in pain, mandibular range of motion, sleep quality, anxiety, stress, depression, and oral health in individuals with bruxism.

Methods/Design

Participants will be randomized into one of three groups: Group 1 (n?=?24) intervention will consist of massage and stretching exercises; Group 2 (n?=?24) will consist of relaxation and imagination therapies; and Group 3 (n?=?24) will receive dental treatment. The evaluations will be performed at baseline, immediately after treatment, and at 2-month follow-up. Pain intensity will be assessed using the visual analogical scale, while pain thresholds will be determined using dolorimetry. Mandibular range of motion will be assessed using digital pachymeter. Sleep quality will be assessed by the Pittsburgh Sleep Quality Index, anxiety by the State-Trait Anxiety Inventory, stress by the Perceived Stress Scale-10, depression by the Beck Depression Inventory, and oral health will be assessed using the Oral Health Impact Profile - 14. Significance level will be determined at the 5% level.

Discussion

This project describes the randomization method that will be used to compare two physical therapy interventions with dental treatment in the management of pain, mandibular range of motion, sleep quality, anxiety, stress, depression, and oral health in individuals with bruxism. The study will support the practice of evidence-based physical therapy for individuals with bruxism. Data will be published after study is completed.

Trial registration

ClinicalTrials.gov, NCT01778881     

Headache and Blood Pressure in the Community

Following a survey of headaches, in which questionnaires were sent to a random sample of the general population, groups of individuals with headache, unilateral headache, or migraine, and a fourth group who had not had a headache in the previous year were examined. Measurements of arterial blood pressure on 414 individuals gave no evidence of any differences between these groups for either systolic or diastolic pressure. The number of individuals that could be regarded as hypertensive in this community-based study was small, but it is concluded that most individuals with headache, and with migraine, have blood pressures similar to those who do not have headaches.     

Learning from Our Treatment Failures

Barton and Blanchard's report that multicomponent behavioral treatment fails to modify chronic daily headaches is discussed with reference to the effectiveness of behavioral and drug treatments for chronic tension-type headache, the distinction between chronic tension-type headache and chronic migraine, and the psychophysiology of episodic vs. persistent pain (K. A. Barton & E. B. Blanchard, 2001). It is suggested that the treatment of chronic daily headache can be improved through research on the benefits of combined behavioral and drug therapy, the psychophysiology of persistent pain, and methods of preventing episodic headaches from evolving to daily headaches.     

Relaxation training as a treatment for chronic headaches in an individual having severe developmental disabilities

We have assessed effects of a simplified relaxation training on the frequency of headaches and consumption of analgesic headache medication in an adult male with severe developmental disabilities as well as chronic mixed headaches. The subject received Behavioral Relaxation Training (BRT) after a baseline period during which frequency of headache complaint, analgesic medication consumption, and independent relaxation behaviors were monitored. BRT consists of the utilization of modeling, prompting, feedback, and positive reinforcement in order to establish and maintain the subject's participation in 10 overt relaxed postures. The behaviors were learned to at least an 80% proficiency during a 10-minute alternating self-regulatory (1 min)/corrective feedback (1 min) relaxation phase across several sessions. Headache complaints were reduced by 48% and analgesic medication consumption by 51% as assessed during a 2-month posttreatment evaluation. These results should be considered not only as support of BRT as a viable method of relaxation training but also as a suggestion that BRT and other self-regulatory treatment should be considered for use with individuals having moderate to severe developmental disabilities.     

Relationship between symptoms of temporomandibular disorders and dental status, general health and psychosomatic factors in two cohorts of 70-year-old subjects

Objective: To study the prevalence of symptoms of temporomandibular disorders (TMD) in two cohorts of 70‐year‐old subjects examined 8 years apart and analyse the relationship between such symptoms and dental status, general health and various background factors. Materials and methods: Two cohorts of 70‐year‐old subjects, born in 1922 (n = 422) and 1930 (n = 491) respectively, were examined with an interval of 8 years. A TMD symptom index (0–5) was established on answers to five questions related to TMD symptoms. Results: There were no statistically significant differences between the two cohorts for prevalence of TMD symptoms and TMD index, neither for headache, neck ache, bruxism and chewing ability. TMJ sounds was the most prevalent symptom, 14%, whereas other TMD symptoms had low prevalence. The distribution of the TMD symptom index showed that 81% reported no symptoms, 15% one symptom, 3% two symptoms and 1% three to five symptoms. Single TMD symptoms and the TMD index exhibited significant associations (p < 0.001) with bruxism, headache, neck pain and several general health and psychosomatic factors, but with dental status only in women. Logistic regression showed that bruxism, neck pain, mouth dryness and a number of psychosomatic factors were associated with the TMD index. Conclusions: Besides TMJ sounds (14%), other TMD symptoms were rarely reported by the 70‐year‐old subjects. The TMD index was significantly associated with bruxism and several general health and psychosomatic complaints but with dental status only in women.     

Dysregulation of the Descending Pain System in Temporomandibular Disorders Revealed by Low-Frequency Sensory Transcutaneous Electrical Nerve Stimulation: A Pupillometric Study

Using computerized pupillometry, our previous research established that the autonomic nervous system (ANS) is dysregulated in patients suffering from temporomandibular disorders (TMDs), suggesting a potential role for ANS dysfunction in pain modulation and the etiology of TMD. However, pain modulation hypotheses for TMD are still lacking. The periaqueductal gray (PAG) is involved in the descending modulation of defensive behavior and pain through μ, κ, and δ opioid receptors. Transcutaneous electrical nerve stimulation (TENS) has been extensively used for pain relief, as low-frequency stimulation can activate µ receptors. Our aim was to use pupillometry to evaluate the effect of low-frequency TENS stimulation of μ receptors on opioid descending pathways in TMD patients. In accordance with the Research Diagnostic Criteria for TMD, 18 females with myogenous TMD and 18 matched-controls were enrolled. All subjects underwent subsequent pupillometric evaluations under dark and light conditions before, soon after (end of stimulation) and long after (recovery period) sensorial TENS. The overall statistics derived from the darkness condition revealed no significant differences in pupil size between cases and controls; indeed, TENS stimulation significantly reduced pupil size in both groups. Controls, but not TMD patients, displayed significant differences in pupil size before compared with after TENS. Under light conditions, TMD patients presented a smaller pupil size compared with controls; the pupil size was reduced only in the controls. Pupil size differences were found before and during TENS and before and after TENS in the controls only. Pupillometry revealed that stimulating the descending opioid pathway with low-frequency sensory TENS of the fifth and seventh pairs of cranial nerves affects the peripheral target. The TMD patients exhibited a different pattern of response to TENS stimulation compared with the controls, suggesting that impaired modulation of the descending pain system may be involved in TMD.     

Preliminary Study of a Self-Administered Treatment for Irritable Bowel Syndrome: Comparison to a Wait List Control Group

Despite the accumulation of efficacy data for cognitive-behavioral treatment of Irritable Bowel Syndrome (IBS), efforts to investigate methods for increasing access to psychological treatments are in their infancy. The current study examined the efficacy of self-administered treatment in comparison to a wait list control. Twenty-eight participants monitored gastrointestinal (GI) symptoms and completed measures of quality of life (QOL) and psychological distress prior to randomized assignment to self-help treatment or wait list. Wait listed participants later received treatment. A 3 month post-treatment follow-up was included. Seven participants completed immediate treatment; nine the wait list. The self-help treatment significantly decreased composite GI symptom scores in comparison to the wait list, but did not lead to significant improvements in QOL or distress. In the entire treated sample, including wait list crossovers, analyses showed significant improvement in abdominal pain, average GI symptoms, and perceived health and well-being. Interpretation of these results should be considered in the context of several limitations, including small sample size, brief baseline symptom monitoring, and high drop out rate. Despite these limitations, this study is an important first step in empirically validating low-cost, self-administered treatments as a first line psychological intervention for IBS.     

Relaxation training as a treatment for chronic headaches in an individual having severe developmental disabilities

We have assessed effects of a simplified relaxation training on the frequency of headaches and consumption of analgesic headache medication in an adult male with severe developmental disabilities as well as chronic mixed headaches. The subject received Behavioral Relaxation Training (BRT) after a baseline period during which frequency of headache complaint, analgesic medication consumption, and independent relaxation behaviors were monitored. BRT consists of the utilization of modeling, prompting, feedback, and positive reinforcement in order to establish and maintain the subject's participation in 10 overt relaxed postures. The behaviors were learned to at least an 80% proficiency during a 10-minute alternating self-regulatory (1 min)/corrective feedback (1 min) relaxation phase across several sessions. Headache complaints were reduced by 48% and analgesic medication consumption by 51% as assessed during a 2-month posttreatment evaluation. These results should be considered not only as support of BRT as a viable method of relaxation training but also as a suggestion that BRT and other self-regulatory treatment should be considered for use with individuals having moderate to severe developmental disabilities.This research was supported in part by grants from NIMH, MH-41341, and NINCDS, NS-23440.     

Glycoprotein electrophoretic patterns have potential to monitor changes associated with neoplastic transformation in oral cancer

Alterations in glycoproteins, important cell surface constituents, have long been associated with various malignancies. The present investigation therefore explored the clinical significance of a glycoproteomics approach in patients with oral precancerous conditions (OPC) and patients with oral cancer. The study included 80 oral cancer patients, 50 patients with OPC, and 84 controls. Native polyacrylamide gel electrophoresis followed by Schiff’s staining was carried out to study the alterations in glycoproteins. The results showed significant elevation (p<0.0001) of 192 kDa, 170 kDa, 116 kDa and 44 kDa glycoproteins in oral cancer patients and patients with OPC compared with controls. The odds ratio indicated a significantly higher risk for oral cancer among users and especially chewers of tobacco. The levels of all the glycoprotein bands (192 kDa, 170 kDa, 116 kDa and 44 kDa) were higher in patients with a habit of tobacco use (WHT) than in patients with no habit of tobacco (NHT) and were also higher in WHT controls than in NHT controls. Moreover, a 230 kDa glycoprotein consistently appeared only in individuals with tobacco habits and an increasing trend was observed from WHT controls to patients with OPC to WHT oral cancer patients. In conclusion, the results indicated the potential utility of glycoprotein alterations in monitoring sequential changes occurring due to tobacco consumption during neoplastic transformation.

     

Controlled Clinical Trial of Ergotamine Tartrate

A double-blind controlled clinical trial of cross-over design for the treatment of headache was conducted in 88 women identified during a community survey as having headaches with the features of migraine. Of 79 subjects who completed the trial, 40 benefited from oral ergotamine tartrate and 46 benefited from the placebo. There was no evidence that ergotamine in doses of 2 or 3 mg. was more effective than the placebo. Ergotamine aggravated the attack significantly more often than the placebo. Neither the colour of the tablets nor the order of therapy significantly affected the results of the treatment.     

Influence of depression and somatization on acute and chronic orofacial pain in patients with single or multiple TMD diagnoses

To examine whether psychological variables such as depression and non-specific physical symptoms (somatization) influence pain entity among acute and chronic TMD patients with one or more TMD diagnoses (muscle disorders, MD; disc displacements, DD; and arthralgia, arthritis, arthrosis, AAA). One hundred and fifty-four patients (37 male and 117 female; mean age, 39.0 +/- 14.5 years) with Research Diagnostic Criteria for Temporomandibular Disorders (RDC/ TMD) protocol were selected. Differences in mean depression and somatization scores between acute and chronic TMD patients, as well as TMD patients with one or multiple TMD diagnoses were compared by using the parametric T-test for independent samples. The majority of patients were acute TMD patients (81.8%), while the remaining 28 patients (18.2%) were chronic TMD patients. 62% of patients had only one TMD diagnosis (MD or DD or AAA), 31% of patients had two diagnoses (MD+DD, MD+AAA, DD+AAA) and, finally, 7% of patients had three diagnoses (MD+DD+AAA) according to the RDC/TMD protocol. According to the SCL-90 psychometric evaluation, 19.5% of patients presented a severe depression score (> 1.105), 27.3% of participants presented a severe somatization score with pain items included (> 1.000). The results of the t-test for independent samples showed statistically significant differences between acute and chronic TMD patients (p < 0.001), as well as between patients who were assigned one diagnosis (p = 0.019) and patients who had two or more diagnoses (p < 0.001); for mean levels of depression and somatization scores. Chronic TMD patients and patients with multiple TMD diagnoses had higher rates of depression and somatization in this study. These results could be used in a tailored strategy of TMD treatment.