Short-term treatment of a resilient appliance in TMD pain patients: a randomized controlled trial

Summary  To investigate the short-term efficacy of a resilient appliance in patients with temporomandibular disorders (TMD) suffering from pain, a randomized, controlled trial was performed in 80 recruited TMD pain patients. They were randomly allocated to one of two groups: treatment with a resilient appliance or treatment with a hard, palatal, non-occluding appliance. The primary treatment outcome measure was judged positive when patients' TMD pain at worst, according to the Visual Analog Scale (VAS), decreased by at least 30%. One additional treatment outcome was reduction of characteristic pain intensity. Number needed to treat was measured on the basis of primary treatment outcome at 10 weeks. At baseline, patient characteristics and TMD pain did not differ between the groups. There were no significant differences between groups regarding a 30% reduction in VAS-reported TMD pain at worst at 10 weeks' follow-up; 61% in the treatment group and 46% in the control group. After 6 and 10 weeks of treatment, CPI decreased in both groups. Number needed to treat was 9·1 for both the resilient and the control appliance therapy during 10 weeks. There was no statistically significant difference between the resilient appliance and the non-occluding control appliance in reducing TMD pain from a short-term perspective.     

A retrospective analysis of temporomandibular findings among Israeli-born patients based on the RDC/TMD

Summary  The purpose of this study was to evaluate temporomandibular disorders (TMD) Axis I and II among Israeli-Jewish patients using the Hebrew version of the Research Diagnostic Criteria (RDC) for TMD and to compare the results with Swedish, United States, Asian and Israeli-Arab populations. The study consisted of 298 Israeli-born, Jewish patients (male/female ratio 3·5:1), arriving at an Orofacial Pain Clinic during the year 2001–2004. A complete clinical examination was carried out according to the RDC/TMD protocol. Axis I diagnoses: 65% of the Israeli-Jewish patients exhibited myofacial pain (Group I disorder), 38% disc displacement (Group II disorder) and 18% arthralgia, osteoarthritis or osteoarthrosis (Group III disorder). Axis II diagnoses: 20% of the patients scored severe depression and 35% scored somatization. Pain was reported in 82% of the patients (mean pain duration 35·7–33·8 months for women, 44·1 for men). Patients had an average disability score of 30·0 ± 30·2. Chronic pain grade IV was present in 4% of the patients. Israeli-Jewish temporomandibular disorder patients showed results similar to those reported for other countries, further supporting the use of the RDC/TMD internationally as a reliable epidemiological tool. Globally, Axis I scores were similar, while Axis II scores were more susceptible to geographic/ethnic differences. Gender can influence Axis I and Axis II as well as possible gender specific association with socio-economic status. In future comparisons, men and women should be considered separately.     

Biopsychosocial correlations in patients with chronic oro-facial pain. Part II. Experiences of pain and dramatic events before the 16th year of life

Summary  Before the sixteenth year of life, biopsychosocial influences such as self-experienced and observed accidents/illnesses, adverse medical/dental treatments, dangerous events and self-experienced or observed force seem to affect the manifestation of chronic pain in the oro-facial area in the forms of temporomandibular disorder (TMD) and psychogenic denture-intolerance (PDI)/somatoform oro-facial pain (SOP). We evaluated the occurrence of these types of events before the age of 16 years in 50 TMD patients, 55 PDI/SOP patients and 55 randomly selected pain-free control group (CG) using the medical questionnaire 'Physical well-being and traumatic experiences (PTE). A separate dental questionnaire determined the effects of previous experiences of pain or force on the emotional self-assessment of the patients (pain localization and body feeling). The TMD group was significantly more likely to have experienced an accident and an illness before the age of 16 years than were the other two groups (PDI/SOP and CG) ( P  <   0·039). Temporomandibular disorder and PDI/SOP patients suffered frequent backaches significantly more than CG patients ( P  <   0·028). The PDI/SOP patients were least likely to report having felt threatened before or after the age of 16 years ( P  <   0·003) compared with the PDI/SOP and CG group. Sociodemographic parameters, experiencing an accident, previous medical incidents, experiences of force and emotional self-assessment influence the biopsychosocial dynamics that directly influence oro-facial symptoms with psychogenic components. Similar to medical history, age seems to play a decisive role in the manifestation of oro-facial psychic symptoms.     

Diagnostic sub-types, psychological distress and psychosocial dysfunction in southern Chinese people with temporomandibular disorders

Summary  The study aimed to assess the distribution of temporomandibular disorders (TMD) sub-types, psychological distress and psychosocial dysfunction in southern Chinese people seeking treatment for TMD using Research Diagnostic Criteria for TMD (RDC/TMD) and investigate potential cross-cultural differences in sub-type prevalence and psychosocial impact. Eighty-seven consecutive patients (77 females; 10 males) with a mean age of 39·3 years (s.d. 12·8) newly referred to the specialist TMD clinic at the Prince Philip Dental Hospital, Hong Kong over a 20-month period took part in the study. RDC/TMD history questionnaire and clinical assessment data were used to derive Axis I and II findings. Group I muscle disorders were the most common and found in 57·5% of patients. Group II (disc displacement) disorders were found in 42·5% and 47·1% of the right and left temporomandibular joints (TMJ) respectively. Group III disorders (arthralgia/arthrosis/arthritis) were revealed in 19·5% and 23·0% of right and left TMJ's respectively. In the Axis II assessment, 42·5% of patients had moderate/severe depression scores, 59·7% had moderate/severe somatization scores and based on graded chronic pain scores 15·0% had psychosocial dysfunction (grade III and IV). While acknowledging the small sample size, the distribution of RDC/TMD Axis I and II diagnoses was fairly similar in Chinese TMD patients compared with Western and other Asian patient groups. However, in Chinese patients, myofascial pain with limited jaw opening and TMJ disc displacement with reduction were more common and a significant number experienced psychological distress and psychosocial dysfunction. The findings have implications for the management of TMD in Chinese people.     

Depression and diffuse physical symptoms in southern Chinese with temporomandibular disorders

Summary  The study investigated the experience of depressive symptoms and the relationship with diffuse physical symptoms reporting in southern Chinese seeking professional care for temporomandibular disorders (TMD) in Hong Kong. Eighty-seven new patients [77 females/10 males; mean age 39·3 years (SD 12·7)] referred to the specialist TMD clinic at the Prince Philip Dental Hospital, Hong Kong participated in this study. The Research Diagnostic Criteria (RDC)/TMD history questionnaire was used to derive Axis II psychological data. Psychological status was assessed through depression and non-specific physical symptoms (NPS) scores (pain items included and excluded) measured with RDC/TMD Axis II instruments; 42·5% of patients experienced moderate/severe depression symptoms; 59·8% and 57·5% had moderate/severe NPS scores when pain items were included and excluded, respectively. Strong, positive and statistically significant correlations were noted between depression scores and the NPS scores that included pain items ( r  = 0·80) and those that did not ( r  = 0·80). The correlations remained consistent and were of similar magnitude when male patients were excluded from the computation and also when the possible effect of patient age was controlled. While taking into account the modest patient sample which was related to a low rate of treatment seeking, depressive symptoms were common and similar to other western and Chinese patient groups. NPS reports were higher than in Singapore Chinese patients. There appeared to be a clear association between depression and diffuse physical symptoms. The findings should be considered in the holistic care of Chinese people with TMD.     

Self-reported symptoms of temporomandibular dysfunction in a female university student population in Saudi Arabia

The symptoms of temporomandibular dysfunction (TMD), reported by 705 female university students of Riyadh, Saudi Arabia, are analysed. The population is representative of the educated class of Saudi Arabia. The most frequently reported symptoms were jaw feeling tired (34·5%), awareness of uncomfortable bite (31·3%), pain in front of the ear (22·4%) and discomfort upon wide opening (22·4%). The frequency of subjective reactions was, pain interferes with activity (42%), disturbed sleep (40·6%), taking of medication (27·8%) and pain being frustrating or depressing (26·8%). Some interesting relationships were found between the reported symptoms and marital status, residence and college of education. These findings are similar to those reported in a Bedouin community in Egypt, but lower than that in a Saudi Arabian population attending dental clinics, Saudi male dental students and high school students.     

Correlation between the levels of non‐specific physical symptoms and pressure pain thresholds measured by algometry in patients with temporomandibular disorders

Recent studies showed that patients with chronic TMD pain also feature increased sensitivity in other craniofacial regions, and even in remote peripheral areas, suggesting that nociceptive processing is centrally facilitated in this patient population. The aim of this study was to investigate the existence of a negative correlation between the levels of non‐specific physical symptoms and pressure pain thresholds measured by algometry at sites distant from the chief complaint of oro‐facial pain in patients with TMD. A total of 20 female patients were evaluated comprising 11 patients diagnosed with myofascial pain (Group I of RDC/TMD) and 9 patients with arthralgia (Group III of RDC/TMD), with both reporting chronic TMD pain for at least 3 months. Patients were tested by the pressure algometry technique, and, in the same visit, clinical diagnosis and levels of non‐specific physical symptoms, including pain‐related issues or not, were obtained. The raw scores were then standardised into a T‐score. The possible correlation between the dependent variable levels of non‐specific physical symptoms and pressure pain thresholds measured by algometry at sites distant from the chief complaint of oro‐facial pain was assessed with Spearman's correlation coefficient. Results were considered statistically significant, which stood a lower than 5% probability of occurring by chance (P < 0·05). A statistically significant (P = 0·02) negative correlation (?0·51) was found to exist between the levels of non‐specific physical symptoms, only if including issues involving pain‐related symptoms, and experimental pressure pain thresholds in patients with painful TMD.     

Self-reported chewing side preference and its associations with occlusal, temporomandibular and prosthodontic factors: results from the population-based Study of Health in Pomerania (SHIP-0)

Summary  This study investigated the prevalence of a preferred chewing side (PCS) and associations between a PCS and signs of temporomandibular disorders (TMD), antagonist contact and prosthetic restoration. A population representative sample of 4086 adults of the cross-sectional epidemiologic 'Study of Health in Pomerania' (SHIP-0) (age range 20–80 years, female 50·2%) was divided in two groups by the presence or absence of a PCS. PCS was evaluated by a questionnaire. Chi-squared tests and multiple logistic regression were used to determine the impact of the relation between a PCS and signs and symptoms of TMD as well as dental factors. The prevalence of a PCS was 45·4%. Women between 40 and 69 years reported more frequently a PCS. There was a preference for the right side (64%). The following independent variables were significantly associated with a PCS: subjective unilateral pain in the temporomandibular joint (TMJ), odds ratio (OR) 2·4; subjective unilateral joint clicking, OR 1·7; unilateral TMJ/muscle pain on palpation, OR 1·6/OR 1·3; loss of one supporting zone (Eichner-Classification), OR 1·9; loss of both supporting zones on one side, OR 2·2, one supporting zone left, OR 1·4; presence of a removable partial denture, OR 1·6; presence of an attachment restoration, OR 1·5. A PCS was found in almost half the study population and was associated with unilateral signs of TMD, most of all TMJ pain and asymmetrical loss of antagonist contact. Despite replacement of lost teeth not all restorations seemed to support bilateral mastication.     

Incidence of symptoms and signs of TMD following third molar surgery: a controlled, prospective study

Summary  The purpose of this prospective study was to investigate if third molar surgery is associated with the development of symptoms and signs of temporomandibular disorders (TMD) during a 6-month post-operative observation period using the Research Diagnostic Criteria for TMD (RDC/TMD) instrument. Seventy-two subjects eligible for third molar surgery under local anaesthesia (patients) were included. Patients were examined according to the RDC/TMD instrument at baseline, 1 week, 1 and 6 months after surgery. Twenty-five age- and sex-matched healthy non-operative control subjects (controls) were included and examined at baseline and at 6 months. In the patient group, we found: (i) reduced range of maximum jaw opening at one week after surgery ( P  < 0·001), (ii) increased characteristic pain intensity 1 week after surgery ( P  < 0·05), (iii) increased disability up to 1 month after surgery ( P  < 0·05), (iv) increased incidence of muscle pain on palpation up to 6 months after surgery ( P  < 0·05), (v) increased incidence of pain on palpation of the temporomandibular joint up to 6 months after surgery ( P  < 0·05) and (vi) increased incidence of painful TMD 6 months after surgery. But, when compared with untreated controls, subjects undergoing third molar surgery have a statistically insignificant increased incidence of TMD 6 months post-operatively.     

TMD chronic pain and masseter silent period in psychiatric patients on antidepressive therapy

Summary  The aim of the study was to evaluate the long-term effects of antidepressive therapy on chronic pain and related disability, and masseter silent period in psychiatric depressive patients with temporomandibular disorders (TMD). The study included hospitalized psychiatric depressive patients on antidepressive therapy protocol (tetracyclic antidepressant-maprotiline and anxiolytic-diazepam) ( n  = 30) and non-psychiatric patients seeking prosthodontic treatment (control group, n  = 38). TMD were diagnosed by Research Diagnostic Criteria for temporomandibular disorders proposed by Dworkin and LeResche. The surface electromyography was recorded from left and right masseter muscles and masseter inhibitory reflex (masseter silent period) was recorded after mechanical stimulation. The incidence of TMD appearance was very similar, of aproximately 40% in both group of patients. The results of the study also indicated a higher prevalence of joint related TMD, a lower prevalence of muscular subtype of TMD and a lower grade of chronic pain and related disability in the psychiatric group of patients on antidepressive therapy in comparison with findings in the control group. In the patients on antidepressive therapy with TMD masseter silent period was not prolonged, while in the control group of patients with TMD the prolongation of the silent period was observed. The study provided evidence that long-term, combined therapy (maprotiline and diazepam) in psychiatric depressive patients significantly modulated signs and symptoms of TMD in comparison with the control group.     

Psychosocial profiles of painful TMD patients

Summary  The aim of the present investigation is to test the null hypothesis that the presence of psychopathology in patients with temporomandibular disorders (TMD) is related to the presence of pain, independent of its location [(i.e. myofascial and/or temporomandibular joint (TMJ) pain]. Ninety-six ( n  = 96) patients affected by painful TMD underwent a clinical assessment in accordance with the research diagnostic criteria for TMD (RDC/TMD) guidelines and filled out the Symptoms Check List – Revised (SCL-90-R) instrument to investigate the presence of symptoms of psychopathology. Patients with myofascial pain, alone or combined with TMJ pain, endorsed the highest scores in all SCL-90-R scales and showed the highest percentage of abnormal values in the depression (DEP) and somatization (SOM) scales for the assessment of depressive and somatization symptoms. Nonetheless, anova revealed no significant differences between groups in any of the SCL-90-R scales, except than in the Positive Symptom Total Index ( F  = 3·463; P  = 0·035), and the chi-squared test did not detect any significant differences between groups for the prevalence of abnormal scores in the DEP and SOM scales. The existence of a close association between pain and psychosocial disorders in TMD patients was supported by the present study. The null hypothesis is that no differences exist between patients with different painful TMD cannot be fully accepted for the presence of psychosocial disorders because of the trend evidencing higher SCL-90-R scores for myofascial pain patients, alone or combined with TMJ pain, with respect to TMJ pain alone.     

Temporomandibular disorder pain in adult Saudi Arabians referred for specialised dental treatment

The aim of this study was to determine the frequency of Temporomandibular Disorders (TMD) pain in Saudi Arabians,aged 20-40, who were referred to the Specialist Dental Centre in Makkah. The material included 325 patients (135 males,190 females) who answered a history questionnaire. Patients reportingTMD pain in the last month were offered a clinical examination. History questionnaires and clinical examinations were done according to the Arabic version of the Research Diagnostic Criteria for TMD (RDC/TMD). Fifty-eight patients (18%) reported TMD pain; 46 were clinically examined. Mean age of clinically examined TMD pain patients was 30 +/- 7 years with a male-female ratio of 1:6 (P < 0.001). All TMD pain patients had a diagnosis of myofascial pain, and 65% had diagnoses of arthralgia or osteoarthritis. Headaches or migraines in the last 6 months and headaches in the last month were reported in high frequencies in the TMD pain group, 93% and 71% respectively, with differences (P < 0.001) between the TMD pain and non-TMD pain groups. Graded Chronic Pain Scale assessments classified 45% of the TMD pain patients in grade 1, 53% in grade II, 2% in grade III, and 0% in grade IV. Severe depression scores were found in 38% of the TMD pain patients and severe somatisation scores in 60% with differences (P < 0.001) between the TMD pain and non-TMD pain groups. In conclusion, the study found a frequency of TMD pain in this Saudi Arabian cohort of 18%. The TMD pain group presented high scores of depression and somatisation but low disability grades on the Graded Chronic Pain Scale.     

Clinical value of 12 occlusal features for the prediction of disc displacement with reduction (RDC/TMD Axis I group IIa)

Summary  The purpose of this study is to quantify the clinical value of 12 occlusal variables for the prediction of disc displacement with reduction diagnosed according to research diagnostic criteria (RDC)/temporomandibular disorder (TMD). Twelve occlusal features were clinically assessed by the same three operators. The sample consisted of 165 TMD patients (65 males, 100 females; mean age: 32·55 ± 11·685years) with only disc displacement with reduction (RDC/TMD Axis I group IIa) and a control sample of 145 healthy subjects (65 males, 80 females; mean age: 31·24 ± 12·436 years) diagnosed with RDC/TMD Axis I group 0. A stepwise multiple logistic regression model was used to identify the significant correlation between occlusal features and disease. The odds ratio for disc displacement was 2·84 for absence of canine guidance, 2·14 for mediotrusive interference and 1·75 for retruded contact position (RCP)/maximum intercuspation (MI) slide ≥2 mm. Other occlusal variables did not reveal to be statistically significant. The percentage of the total log likelihood for disc displacement explained by the significant occlusal factors was acceptable with a Nagelkerke's R² = 0·124. The final model including the significant occlusal features revealed an optimal discriminant capacity to predict patients with disc displacement with a sensitivity of 63·6% or with a specificity of 64·8% for healthy subjects and an accuracy of 64·2%. Occlusal features showed a low predictive value for detecting disc displacement. Multifactorial complex pathologies such as TMD should be investigated using a multivariate statistical analysis; moreover, the future of aetiopathogenic research in this matter requires a multifactorial approach.     

The diagnostic value of pressure algometry in myofascial pain of the jaw muscles

Recent evidence suggests that evaluation of muscle tenderness in temporomandibular disorders (TMDs) patients might be improved by the use of pressure algometry; nevertheless, the evaluation of the diagnostic value of this tool has received little attention. The aim of this study was to assess the diagnostic value of pressure algometry in myofascial pain of the jaw muscles, by calculation of sensitivity (Se), specificity (Sp) and positive predictive values (PPV). Pressure pain thresholds (PPTs) of masseter and anterior temporalis muscles were assessed in 40 female myogenous TMD patients and 40 age-matched female controls. PPTs were significantly lower ( P <0·001) in TMD patients than in control subjects for both masseter and temporalis muscles, being 40–50% of the control values. Setting a cutoff value 1 s.d. below the mean PPT values of control subject, sensitivity and specificity were 0·67 and 0·85, respectively, for the masseter muscle and 0·77 and 0·87, respectively, for the temporalis muscle. When taking into account the prevalences of myofascial pain in the general population and in TMD clinics, the PPV ranged from 0·5 to 0·7. As a result of the low PPV, pressure algometry has strong limitations when used as a solitary diagnostic tool.     

Comparison of pain thresholds and pain tolerance levels between Middle Easterners and Swedes and between genders

Summary  Objective: This study evaluates the presence of culture and gender differences in pain thresholds and pain tolerance levels between Middle Easterners and Swedes. Methods: Sixty-four healthy individuals, 32 Middle Easterners (16 men and 16 women, mean age: 24·6 ± 3·4 years) and 32 Swedes (16 men and 16 women, mean age: 24 ± 3·5 years) participated in the study. Three experimental pain tests were conducted in each participant. Pain thresholds and pain tolerance levels were measured using an algometer (mechanical stimulus), the PainMatcher^® (electric stimulus) and cold pressor test (thermal stimulus). Results: While no significant differences in pain thresholds were observed between Middle Easterners and Swedes in algometer and cold pressor tests, differences in pain tolerance levels were significant ( P  < 0·01 for both tests). All between-culture differences in pain perception, pain threshold and pain tolerance level were non-significant when measured with the PainMatcher. Significant between-gender differences were observed only in pain threshold with the PainMatcher ( P  <   0·05) and in pain tolerance level with the algometer ( P  <   0·01) and the PainMatcher ( P  <0·001). Conclusion: This study found significant differences in two out of three pain tolerance level tests – but not pain threshold tests – between the Middle Eastern and Swedish cultures and between genders. These differences were more pronounced between Middle Eastern and Swedish men than between Middle Eastern and Swedish women. Gender differences were more pronounced within the Swedish than the Middle Eastern culture. These findings indicate that culture and gender influence pain experience.     

Salivary cortisol and IgA levels in patients with myofascial pain treated with occlusal appliances in the short term

Summary  In many studies, the endocrinological response of individuals to different kinds of stresses has been tested. There seems to be widespread agreement that stress, depression, disability and dysfunctional illness behaviors are critical aspects of patients suffering from symptoms like pain, arising out of temporomandibular disorders (TMD). We aimed to explore treatment-induced changes in salivary cortisol, IgA and flow rate values in TMD patients suffering from myofascial pain. Temporomandibular disorders patients ( n  = 39) were randomized into two groups and treated with two different occlusal appliances. Perceived stress regarding family, work, economy, relationships, general health and stress in general was evaluated at baseline according to a verbal scale. Paraffin-stimulated saliva samples were collected before treatment and during follow-up at 6 and 10 weeks. Flow rate was measured immediately after the saliva collection while salivary cortisol and IgA were determined from samples stored at −70 °C. No clear association between reported stress and cortisol or IgA values could be observed at baseline. At 10 weeks follow-up, 92% of the patients felt 'better, much better, symptom-free' and no difference was found between the two appliance groups. Cortisol, IgA and flow rate values showed no systematic between appliance groups' differences. All salivary parameters showed interindividual differences but stayed intra-individually on a similar level throughout the study and no statistically significant changes could be observed when comparing before and after treatment levels. To conclude, there were no treatment-induced changes in saliva parameters despite successful appliance therapy in myofascial pain patients.     

Examining the Sensitivity and Specificity of 2 Screening Instruments: Odontogenic or Temporomandibular Disorder Pain?

Introduction

Two groups of patients with orofacial pains that are clinically important to distinguish from each other are patients with odontogenic pain and temporomandibular disorder (TMD) pain. The aim of this study was to determine the sensitivity and specificity of 2 screening instruments in distinguishing between patients with these types of pain.

The effect of tooth clenching on the sensory and pain perception in the oro-facial region of symptom-free men and women

Summary  The aim of this study was (i) to examine the effect of light tooth contact as in diurnal tooth clenching on the tactile detection threshold (TDT), the filament-prick pain detection threshold (FPT) and the pressure pain threshold (PPT) in the oro-facial region and (ii) to examine the possible gender difference in this effect on the tactile and pain perception. Twenty healthy volunteers participated. The TDT and the FPT were measured by means of Semmes-Weinstein monofilaments, on the cheek skin (CS) overlying the masseter muscles (MM) and on the skin overlying the palm side of the thenar skin (TS). The PPT was measured at the central part of the MM using a pressure algometer. Each parameter was measured before and after keeping light tooth contact for 5 min (session 1) and after keeping the jaw relaxed for 5 min (session 2) as a control. Although there were no significant session effects on any of the parameters, there were significant effects of experimental condition on the TDT in both men and women ( P  <   0·001). Men had a significant higher FPT of the left CS ( P  <   0·05) and TS ( P  <   0·01) and a significant higher PPT of the MM than women ( P  <   0·001). These results illustrate that sensitivity to pain (FPT, PPT) was higher in women than in men. Although there were no significant gender differences in habituation of sensory perception, the increase of TDT after clenching/no clenching was larger in women, which warrants further study.