Temporomandibular joint internal derangements and associated neuromuscular disorders

Treatment of temporomandibular joint internal derangement using MESNA injection

INTRODUCTION

The development of temporomandibular disorders specifically emphasizes the biochemical changes occurring in the synovial fluid at different stages of temporomandibular joint disease. Research has indicated that inflammation may be a primary reason behind the pain and dysfunction in temporomandibular joint diseases. Since its clearance several years ago, MESNA (sodium 2-mercaptoethanesulfonate) has been used in various formulations as a mucolytic drug in the respiratory domain. It operates by disrupting the disulfide bonds present between polypeptide chains within mucus. MESNA exhibits minimal tissue distribution, with the material being swiftly and thoroughly eliminated via the kidneys.

OBJECTIVES

To assess the efficacy of injecting MESNA directly into the Temporomandibular Joint to treat internal derangement.

MATERIALS AND METHODS

A randomized clinical trial was conducted on sixty patients who exhibited non-responsiveness to conventional treatment and were diagnosed with TMJ anterior disc displacement with reduction. The patients were chosen from the outpatient clinic of the Oral and Maxillofacial Surgery Department at Tanta University Faculty of Dentistry. Two equal groups of patients were randomly assigned to each other. Group I (Mesna group) received intra-articular injection with MESNA solution. Group II (Standard group) received arthrocentesis with lactated ringer solution followed by injection of Hyaluronic Acid (HA). The data was gathered by functional examinations such as maximum interincisal opening (MIO) and clicking. A Visual Analogue Scale (VAS) assessed pain severity before and after treatments.

RESULTS

Both MESNA and HA showed significant improvement up to six months of the follow-up compared to preoperative status, as evidenced by better mouth opening, lateral excursion, lower clicking, and reduced pain score in patients with TMDs. MESNA showed significant improvement during follow-up compared to HA.

CONCLUSION

Compared to HA, MESNA showed a more noticeable improvement during the follow-up period.

Temporomandibular Joint Disorders: A Pictorial Review

Temporomandibular joint (TMJ) disorders are commonly encountered in the general population but often ignored or unrecognized. The detection and characterization of lesions has drastically improved over the years due to technological advances in cone beam computed tomography (CBCT) and magnetic resonance imaging (MRI). However, adequate knowledge of the normal imaging appearance on different imaging modalities as well as the broad variety of pathology is required to provide a proper radiologic assessment. This pictorial review focuses on TMJ pathology and its appearance on CBCT and MRI. A short overview of the technical aspects and normal anatomy are provided to round out this complete summary on the subject.

A new biofeedback approach for the control of awake bruxism and chronic migraine headache: utilization of an awake posterior interocclusal device

BACKGROUND

The relationship of bidirectional comorbidity between chronic migraine and pain in the cephalic segment led us to evaluate the improvement in reducing the pain in patients diagnosed with chronic migraine headache and awake bruxism, when undergoing treatment with a partial posterior interocclusal device designed for the management and control of awake bruxism through biofeedback.

METHODS

Seventy-four patients were evaluated during the following periods: pretreatment, seven, thirty, ninety, one hundred and eighty days, and one year. The evaluation was carried out by measuring the pain in the pretreatment period and pain reduction after awake bruxism treatment, using clinical evaluation and numerical scales for pain.

RESULTS

Most of the patients who complained of headache migraine pain, masticatory myofascial pain, temporomandibular joint and neck pain experienced a significant reduction in overall pain, including headaches, between t0 and t30 (p<0.0001). After 30 days of using the device, it was observed that the improvement remained at the same level without any recurrence of pain up to t90. At t180 and t360, it was observed that even with the device withdrawal (at t90) the improvement remained at the same level.

CONCLUSION

The utilization of a posterior interocclusal device designed for the management and control of awake bruxism through biofeedback seems to contribute to the reduction of pain (including migraine headache) in the majority of patients, and, even with the device withdrawal (at t90), the improvement remained at the same level, suggesting the patients succeeded in controlling their awake bruxism and consequently the pains.

A new biofeedback approach for the control of masseter and temporal myalgia: Utilization of an awake posterior interocclusal device

Objective: To evaluate the improvement in reducing the pain of patients diagnosed with masticatory myofascial pain and bruxism when undergoing treatment with a partial posterior interocclusal device for the management and control of awake bruxism through biofeedback. Methods: Sixty patients were evaluated during the following periods: pretreatment, 7, 30, and 90 days. The evaluation was carried out by measuring the reduction in pain using clinical and numerical scales. Results: The majority of the patients who complained of masticatory myofascial pain, TMJ, and neck pain experienced a significant reduction in pain between t0 and t30 (p < 0.0001). After 30 days of using the device, the improvement remained at the same level, without any recurrence of pain up to t90. Conclusion: The utilization of a posterior interocclusal device for the management and control of awake bruxism through biofeedback contributed to the reduction of pain in the majority of patients.

Perspectives on next steps in classification of oro-facial pain - part 1: role of ontology

The purpose of this study was to review existing principles of oro-facial pain classifications and to specify design recommendations for a new system that would reflect recent insights in biomedical classification systems, terminologies and ontologies. The study was initiated by a symposium organised by the International RDC/TMD Consortium Network in March 2013, to which the present authors contributed. The following areas are addressed: problems with current classification approaches, status of the ontological basis of pain disorders, insufficient diagnostic aids and biomarkers for pain disorders, exploratory nature of current pain terminology and classification systems, and problems with prevailing classification methods from an ontological perspective. Four recommendations for addressing these problems are as follows: (i) develop a hypothesis-driven classification structure built on principles that ensure to our best understanding an accurate description of the relations among all entities involved in oro-facial pain disorders; (ii) take into account the physiology and phenomenology of oro-facial pain disorders to adequately represent both domains including psychosocial entities in a classification system; (iii) plan at the beginning for field-testing at strategic development stages; and (iv) consider how the classification system will be implemented. Implications in relation to the specific domains of psychosocial factors and biomarkers for inclusion into an oro-facial pain classification system are described in two separate papers.

Trends in management of myofacial pain

We systematically reviewed the myofascial pain publications in the literature. The aim of this article is to review the methods of management and their outcome and factors associated with prognosis. The topics of interest in the diagnostic process are myofascial trigger points electromyography, jaw tracking, joint sound recorder, sonography, and vibratography, exclusion of other orofacial pain and temporomandibular disorders. Management modalities are occlusal therapy, physiotherapy, multidimensional rehabilitation antinociceptive therapy, anti-inflammatory and analgesics, muscle relaxants, stretch, and spray technique, transcutaneous electric nerve stimulation, and in severe cases botulinum toxin may be tried. The disease required interdisciplinary interaction in terms of occlusal therapy, antinociceptive therapy and physiotherapy because management of the disease may be influenced by the specialist primarily treating the patients.

[Craniomandibular disorder/dysfunction. Characteristics and disorders of the masticatory organ]

The practising physician often meets patients with pain located in different parts of the face and facial skull, mouth opening restriction or other motion disorder of the mandible. It is not always easy to identify and explain the cause. It is not widely known among doctors that most of these problems are due to masticatory dysfunction. There is a special group of patients showing functional disorders and there are some others who present a variety of different symptoms and visit several doctors. The masticatory organ, a functional unit of the human organism has a definite and separate task and function. In the early years of life it is capable of adaptation, while later on it tends to compensation. The authors outline the functional anatomy of the masticatory organ and the characteristics of multicausal pathology, the dynamics of the process of the disease and their interdisciplinary aspects. They discuss the basic elements of craniomandibular dysfunction. Based on the diagnostic algorithm, they summarize treatment options for masticatory function disorders. They emphasize the importance that physicians should offer treatment, especially an irreversible treatment, without a diagnosis. It occurs very often that the causes are identified after the patients become symptom-free due to treatment. The aim of this report is to help the general practitioners, dentists, neurologists, ear-nose-throat specialists, rheumatologists or any other specialists in the everyday practice who have patients with different symptoms such as pain in the skull, acoustic phenomenon of the joint or craniomandibular dysfunction.

Signal intensity on fluid-attenuated inversion recovery images of condylar marrow changes correspond with slight pain in patients with temporomandibular joint disorders

OBJECTIVES

Edema and necrosis of the temporomandibular joint (TMJ) have been described in terms of bone marrow signal abnormalities in magnetic resonance imaging (MRI). However, painful joints often show no such signaling abnormalities, making the diagnosis of TMJ disorders difficult in the clinical setting. An association has been suggested between TMJ bone marrow change and TMJ pain, but even when such change results in slight pain, it may be too slight to be visually apparent on MR images. We hypothesized that fluid-attenuated inversion recovery (FLAIR) can be used to detect such minimal changes. The purpose of this study was to determine whether there is an association between signal intensity on FLAIR images and pain in the TMJ.

METHODS

The study included 85 TMJs in 45 patients referred to our department for MRI. The signal intensity on FLAIR images was measured. Pain was evaluated based on the visual analog scale. An unpaired t test and Pearson's product-moment correlation coefficient were used for the statistical analysis. A p value of <0.05 was considered statistically significant.

RESULTS

Signal intensity on the FLAIR images was significantly higher in painful than in nonpainful TMJs, although a significant correlation was not observed between the signal intensity and the pain score.

CONCLUSIONS

The results of this study suggest an association between abnormalities in the marrow of the mandibular condyle and pain. They also indicate that FLAIR imaging is a useful tool in the clinical diagnosis of painful TMJs.

The relationship between malocclusion, benign joint hypermobility syndrome, condylar position and TMD symptoms

The current study investigated the association between temporomandibular disorders, malocclusion patterns, benign joint hypermobility syndrome and the initial condylar position. One hundred sixty-two subjects were analyzed using the Rocabado Temporomandibular Pain Analysis; Helkimo Index parameters; the Carter-Wilkinson modified test; and a mounting cast with condylar position indicator registration (MPI). The study revealed a significant association between: 1. Delta H, skeletal pattern (p = 0.034); 2. Delta Y, transversal malocclusion (p = 0.04); 3. right and left, Delta Z, right and left posteroinferior synovial pain (p < 0.05); 4. hypermobility scale, gender (p < 0.001), malocclusion pattern (p = 0.021); 5. TMJ function impairment, gender (p = 0.043); 6. sagittal malocclusion pattern, right temporomandibular pain analysis joint (TPAJ) (p = 0.0034); 7. TMJ function impairment, left and right TPAJ (p = 0.007); and 8. mandibular motion, left and right TPAJ (p = 0.035, p = 0.015). The conclusion was that anterior crossbite and condylar displacements in the vertical plane are risk factors in developing TMJ symptoms.

Os efeitos da desativação dos pontos-gatilho miofasciais, da mobilização articular e do exercício de estabilização cervical em uma paciente com disfunção temporomandibular: um estudo de caso

INTRODUÇÃO: A disfunção temporomandibular (DTM) pode alterar o equilíbrio dinâmico das estruturas, levando a uma série de sinais e sintomas característicos dessa disfunção, sendo a dor a principal delas. A DTM acomete grande parte da população mundial, o que torna essencial o desenvolvimento de técnicas terapêuticas para seu tratamento. OBJETIVO: O objetivo deste estudo foi verificar a eficácia do tratamento fisioterapêutico em uma paciente com DTM. MATERIAIS E MÉTODOS: Pesquisa experimental, um relato de caso com uma paciente com disfunção temporomandibular, tratamento fisioterapêutico com técnicas de desativação de pontos-gatilho, mobilização articular, estabilização segmentar e exercícios funcionais, sendo realizados duas vezes por semana, com duração de 30 minutos, durante oito semanas. RESULTADOS: A paciente apresentou melhora na dor, na função muscular, na amplitude de movimento e na postura. Portanto, podemos concluir que a intervenção fisioterapêutica tem grandes chances de melhorar o quadro clínico da DTM, juntamente com outras áreas, por ser uma patologia multifatorial.

Orthodontic Effects on Dentofacial Morphology in Women with Bilateral TMJ Disk Displacement

OBJECTIVE

To determine the difference in skeletal response to orthodontic treatment between patients with bilateral disk derangement and normal disk position of the temporomandibular joint (TMJ).

MATERIALS AND METHODS

Subjects consisted of 46 women whose malocclusions were treated only by orthodontics. All patients had TMJ magnetic resonance imaging (TMJ MRI) taken prior to orthodontic treatment. They were classified into three groups according to results of the TMJ MRI: bilateral normal disk position (BN), bilateral disk displacement with reduction (BDDR), and bilateral disk displacement without reduction (BDDNR). Twenty cephalometric variables were evaluated by the Kruskal-Wallis test to identify any differences in morphological changes between the three groups during orthodontic treatment.

RESULTS

This study showed that patients with BDDNR had more severe sagittal and vertical skeletal discrepancies than those with BN and BDDR at the pretreatment stage with discrepancies maintained after treatment. Compared to patients with BN, BDDR patients exhibited significant changes in SNB, N perpendicular to pogonion, SN to mandibular plane angle, total anterior facial height, ramus inclination, and effective mandibular length during treatment. This means that patients with BDDR showed more backward movement and rotation of the mandible than those with BN. In contrast, patients with BDDNR who had the most severe skeletal discrepancies did not show any significant skeletal changes during orthodontic treatment compared to those with BN or BDDR.

CONCLUSION

In patients with bilateral TMJ disk displacement, orthodontic treatment should be undertaken carefully to prevent backward rotation and movement of the mandible.

Discrimination of internal derangement of temporomandibular joint by lateral cephalometric analysis

INTRODUCTION

The purposes of this study were to analyze the progress of internal derangement (ID) of the temporomandibular joint (TMJ) and to find critical yardsticks that can be used during lateral cephalometric analysis to identify subjects with potential ID.

METHODS

The sample consisted of 134 women whose primary complaints were malocclusions. They were divided into 5 groups based on the results of magnetic resonance imaging of bilateral TMJs: bilateral normal disc position, unilateral disc displacement with reduction (DDR) and contralateral normal disc position, bilateral DDR, unilateral DDR and contralateral disc displacement without reduction (DDNR), and bilateral DDNR. Thirty-six cephalometric variables from their lateral cephalograms were analyzed with 1-way ANOVA and discriminant analysis to determine the key factors in identifying subjects with TMJ ID.

RESULTS

Backward positioning of the mandible, clockwise rotation of the mandible, proclination of the mandibular incisors, and increase in overjet intensified gradually with the progression of TMJ ID, and the subjects with bilateral DDNR showed the greatest changes in dentofacial morphology. Stepwise variable selection in discriminant analysis identified the following 2 variables: mandibular incisor to Frankfort horizontal plane angle and overjet. Discriminant analysis resulted in the correct classification of 79.1% of the subjects and showed that those with smaller mandibular incisor to Frankfort horizontal plane angles and larger overjets had high possibilities of TMJ ID.

CONCLUSIONS

This study suggests that some cephalometric variables can be used as an auxiliary diagnostic tool to help identify patients with potential TMJ ID.

3-D sonography for diagnosis of disk dislocation of the temporomandibular joint compared with MRI

This study determines the value of three-dimensional (3-D) sonography for the assessment of disk dislocation of the temporomandibular joint (TMJ). Sixty-eight patients (i.e.,136 TMJ) with clinical dysfunction were examined by 272 sonographic 3-D scans. An 8- to 12.5-MHz transducer, angulated by step-motor, was used after picking a volume box on 2-D scan; magnetic resonance imaging followed immediately. Every TMJ was scrutinized in closed- and open-mouth position for normal or dislocated disk position. Fifty-three patients had complete data sets, i.e., 106 TMJ, 212 examinations. Sonographic examination took 5 min, with 74% specificity (62% closed-mouth; 85% open-mouth); sensitivity 53% (62/43%); accuracy 70% (62/77%); positive predictive value 49% (57/41%); and negative predictive value 77% (67/86%). This study encourages more research on the diagnostic capacity of 3-D TMJ sonography, with the advantage of multidimensional joint visualization. Although fair in specificity and negative predictive value, sensitivity and accuracy may ameliorate with future higher-sound frequency, real-time 3-D viewing and automated image analysis.

Reliability of clinical temporomandibular disorder diagnoses

Temporomandibular disorders (TMD) diagnoses can be viewed as the most useful clinical summary for classifying subtypes of TMD. The Research Diagnostic Criteria for TMD (RDC/TMD) is the most widely used TMD diagnostic system for conducting clinical research. It has been translated into 18 languages and is used by a consortium of 45 RDC/TMD-based international researchers. While reliability of RDC/TMD signs and symptoms of TMD has been amply reported, the reliability of RDC/TMD diagnoses has not. The aim of the study was to determine the reliability of clinical TMD diagnoses using standardized methods and operational definitions contained in the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). Data came from reliability assessment trials conducted at 10 international clinical centers, involving 30 clinical examiners assessing 230 subjects. Intraclass correlation coefficients (ICC) were calculated to characterize the reliability. The reliability of the diagnoses was fair to good. Median ICCs for the diagnoses myofascial pain with and without limited opening were 0.51 and 0.60, respectively. Median ICC for arthralgia was 0.47 and 0.61 for disc displacement with reduction. RDC/TMD diagnoses of disc displacement without reduction, osteoarthritis and osteoarthrosis were not prevalent enough to calculate ICC's, but percent agreement was always >95%. The reliability of diagnostic classification improved when diagnoses were grouped into pain versus non-pain diagnoses (ICC=0.72) and for detecting any diagnosis versus no diagnosis (ICC=0.78). In clinical decision-making and research, arriving at a reliable diagnosis is critical in establishing a clinical condition and a rational approach to treatment. The RDC/TMD demonstrates sufficiently high reliability for the most common TMD diagnoses, supporting its use in clinical research and decision making.

Diagnostic quality of dynamic high-resolution ultrasonography of the TMJ--a pilot study

The aim of this study was to compare sensitivity, specificity, accuracy and positive and negative predictive value for high-resolution ultrasonography (HR-US) in diagnosing degenerative changes, effusion and disk displacement using magnetic resonance imaging (MRI) as a reference. Over a period of 6 months, 100 patients with TMJ disorders (200 TMJs) were investigated by an experienced radiologist with HR-US and magnetic resonance imaging (MRI). The MRI investigation showed degenerative changes in 190 joints (95%), while an effusion was found in 59 (29.5%) joints. At closed-mouth position a disc dislocation was found in 138 joints (69%) and in maximum-mouth-opening position disc dislocation was diagnosed in 76 joints (38%). In the determination of degenerative changes HR-US showed a sensitivity of 94%, a specificity of 100% and an accuracy of 94%. In the detection of effusion HR-US yielded a sensitivity of 81%, a specificity of 100% and an accuracy of 95%. In the determination of disk displacement at closed-mouth position HR-US showed a sensitivity, specificity and an accuracy of 92% each. At maximum-mouth-opening position HR-US reached a sensitivity of 86%, a specificity of 91% and an accuracy of 90%. The results of the current study imply that HR-US is a valuable diagnostic imaging method of the TMJ which can be used as an alternative method to a MRI-investigation, but is yet not able to replace it. Further studies have to be done to reduce false-negative results.

Chronic myofascial pain, disk displacement with reduction and psychosocial factors in Finnish non-patients

This study aimed to determine chronic groups of myofascial pain and chronic disk displacement with reduction over a 1-year period, and to study the relationship between psychological status and these chronic subgroups of temporomandibular disorders (TMD) in non-patients. A total of 211 subjects (males 47%, mean age 46 years; standard deviation 6) attended examinations in 1999 and 2000 performed according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). Chronic myofascial pain was found in 7% and chronic disk displacement with reduction in 11% of subjects; new diagnoses were made in only 4% and 1% of the subjects, respectively. An increase in the level of somatization by 1 step increased the probability of having chronic myofascial pain by over 3 times (P = 0.006). Myofascial pain and disk displacement with reduction seem to be relatively common and fluctuating in nature in non-patients. As somatization associated significantly with myofascial pain, this should be borne in mind in the management of TMD. The results strengthen the rationale of the biopsychosocial orientation in health care.

Cephalometric keys to internal derangement of temporomandibular joint in women with Class II malocclusions

The aim of this study was to find cephalometric keys to provide information on the progression of temporomandibular internal derangement. The sample consisted of 58 women with Class II malocclusions. They were examined with routine lateral cephalograms and magnetic resonance imaging of the temporomandibular joint (TMJ) before orthodontic treatment. They were classified into 3 groups according to the results of the magnetic resonance imaging: normal disk position, disk displacement with reduction, and disk displacement without reduction. Thirty-four cephalometric variables regarding their pretreatment lateral cephalograms were analyzed by 1-way analysis of variance to evaluate the differences in the dentofacial morphology among the 3 groups. The results showed a decrease in posterior facial height, a decrease in ramus height, and backward rotation and retruded position of the mandible in the subjects with internal derangement of the TMJ. These changes were less severe in those with disk displacement with reduction and more severe as internal derangement progressed to disk displacement without reduction. The results suggest that internal derangement of the TMJ might induce dentofacial changes, and that some cephalometric variables can assist in identifying potential patients with internal derangement of the TMJ.

Convergence of nociceptive information from temporomandibular joint and tooth pulp afferents on C1 spinal neurons in the rat

The aim of the present study was to test the hypothesis that there is a convergence of afferent inputs from the temporomandibular joint (TMJ) on C1 spinal neurons responding to electrical stimulation of the tooth pulp (TP). In 14 pentobarbital anesthetized rats, the extracellular single unit activity of 31 C1 spinal neurons and the amplitude in a digastric muscle electromyogram (n = 31) increased proportionally during 1.0-3.5 times the threshold for the jaw-opening reflex (JOR). Of 31 C1 spinal neurons responsive to TP afferents, 28 (approximately 90%) were also excited by electrical stimulation of the ipsilateral TMJ capsule. All neurons tested were divided into three categories of nociceptive specific, wide dynamic range and non-responsive as to their responsiveness to mechanical stimuli (pin prick and touch) of the somatic receptive field (skin of the face, neck, jaw and upper forearm) and TMJ capsule. Nineteen (68%) of 28 C1 spinal neurons received nociceptive information from C fibers of the TMJ capsule. These results suggest that there is a convergence of noxious information from the TMJ and TP afferents on the same C1 spinal neurons, which importantly contribute to pain perception from the TMJ region.

Pain from the oral cavity

The head, face, mouth, and throat collectively is the most frequent site of pain in humans. Facial pain is a particularly distressing problem because identification and effective treatment of the underlying cause is often challenging and sometimes elusive. This article focuses on the more common causes of facial pain that originate in the oral cavity and associated structures and outlines a general approach to diagnosis and management of these problems.

Temporomandibular joint internal derangement: detection with 12.5 MHz ultrasonography

The purpose of this study was to determine whether 12.5 MHz ultrasonography (US) could be used to assess the presence or absence of temporomandibular joint (TMJ) internal derangement (ID). In 48 consecutive patients with TMJ disorders 192 TMJ positions were investigated by US to analyse the functional disc-condyle relationship (DCR). In order to compare the respective findings with those of a diagnostic method offering a high accuracy, coronal and sagittal magnetic resonance imaging was carried out immediately afterwards. With US showing a sensitivity of 0.58 and 0.75, and a specificity of 0.92 and 0.84 for disc displacement with and without reduction, the data revealed US to be marginal in detecting the presence, but sensitive in detecting the absence of the respective types of a TMJ ID. In addition, with a positive predictive value of 0.83 and 0.71, and a negative predictive value of 0.81 and 0.87 for disc displacement with and without reduction, the results indicate that US may be insufficient in establishing a correct diagnosis for the presence or absence of the respective types of TMJ ID. Regarding the diagnosis of absence or presence of TMJ ID, the results demonstrate high-resolution (HR)-US to be sensitive in detecting the absence, and reliable in predicting the presence of TMJ ID. In view of the fact that the 12.5 MHz US technique proved to be a reliable diagnostic aid for the detection of normal, and the prediction of abnormal DCR, the results of this study should be of further interest and encourage research in its potential uses and diagnostic capabilities.

Facial arthralgia and myalgia: can they be differentiated by trigeminal sensory assessment?

Heat and electrical detection thresholds were assessed in 72 patients suffering from painful temporomandibular disorder. Employing widely accepted criteria, 44 patients were classified as suffering from temporomandibular joint (TMJ) arthralgia (i.e. pain originating from the TMJ) and 28 from myalgia (i.e. pain originating from the muscles of mastication). Electrical stimulation was employed to assess thresholds in large myelinated nerve fibers (Abeta) and heat application to assess thresholds in unmyelinated nerve fibers (C). The sensory tests were performed bilaterally in three trigeminal nerve sites: the auriculotemporal nerve territory (AUT), buccal nerve territory (BUC) and the mental nerve territory (MNT). In addition, 22 healthy asymptomatic controls were examined. A subset of ten arthralgia patients underwent arthrocentesis and electrical detection thresholds were additionally assessed following the procedure. Electrical detection threshold ratios were calculated by dividing the affected side by the control side, thus reduced ratios indicate hypersensitivity of the affected side. In control patients, ratios obtained at all sites did not vary significantly from the expected value of 'one' (mean with 95% confidence intervals; AUT, 1:0.95-1.06; BUC, 1.01:0.93-1.11; MNT, 0.97:0.88-1.05, all areas one sample analysis P>0.05). In arthralgia patients mean ratios (+/-SEM) obtained for the AUT territory (0.63+/-0.03) were significantly lower compared to ratios for the MNT (1.02+/-0.03) and BUC (0.96+/-0.04) territories (repeated measures analysis of variance (RANOVA), P<0.0001) and compared to the AUT ratios in myalgia (1.27+/-0.09) and control subjects (1+/-0.06, ANOVA, P<0.0001). In the myalgia group the electrical detection threshold ratios in the AUT territory were significantly elevated compared to the AUT ratios in control subjects (Dunnett test, P<0.05), but only approached statistical significance compared to the MNT (1.07+/-0.04) and BUC (1.11+/-0.06) territories (RANOVA, F(2,27)=3.12, P=0.052). There were no significant differences between and within the groups for electrical detection threshold ratios in the BUC and MNT nerve territories, and for the heat detection thresholds in all tested sites. Following arthrocentesis, mean electrical detection threshold ratios in the AUT territory were significantly elevated from 0.64+/-0.06 to 0.99+/-0.04 indicating resolution of the hypersensitivity (paired t-test, P=0.001). In conclusion, large myelinated fiber hypersensitivity is found in the skin overlying TMJs with clinical pain and pathology but is not found in controls. In patients with muscle-related facial pain there was significant elevation of the electrical detection threshold in the AUT region.

An audit of 405 temporomandibular joint arthrocentesis with intra-articular morphine infusion

The management of refractory pain in the temporomandibular joint (TMJ) is both challenging and controversial. Arthrocentesis is a simple technique that can be used instead of more invasive procedures in patients with pain that fails to respond to conventional conservative measures. We undertook an audit of 405 arthrocenteses in 298 patients over a 10-year period who had refractory pain in the TMJ. The pain was assessed subjectively by a visual analogue scale, both before arthrocentesis and at 1 and 6 months, and 1 year afterwards. A significant reduction in pain score was found after arthrocentesis (P < 0.001) and 269 patients (90%) found the procedure beneficial. We recommend arthrocentesis as an effective, minimally invasive technique in patients with continuing pain in the TMJ that is unresponsive to conservative management.

Are high-resolution ultrasonographic signs of disc displacement valid?

PURPOSE

The study goal was to define the positive predictive value (PPV) for the diagnosis of disc displacement of the temporomandibular joint (TMJ) with the use of high-resolution ultrasonography (HR-US).

MATERIALS AND METHODS

The HR-US reports for 29 patients aged 19 to 62 years who had a prospective clinical diagnosis of TMJ internal derangement were correlated with magnetic resonance results.

RESULTS

For the prospective HR-US interpretation, the PPV for disc displacement was 97% at the closed-mouth position and 88% at the maximum-mouth opening position.

CONCLUSION

The PPV for the HR-US diagnosis of disc displacement is high.

The biological concept of "internal derangement and osteoarthrosis": a diagnostic approach in patients with temporomandibular joint pain?

OBJECTIVES

We sought to investigate whether the finding of temporomandibular joint (TMJ)-related pain may be linked to magnetic resonance (MR) imaging findings of TMJ internal derangement and TMJ osteoarthrosis.

STUDY DESIGN

The study consisted of 194 consecutive TMJ patients. Criteria for including a patient with a painful TMJ were as follow: report of orofacial pain in the TMJ, with the presence of unilateral or bilateral TMJ pain during palpation, function, and unassisted or assisted mandibular opening. Criteria for including a patient with a nonpainful TMJ were as follow: absence of a TMJ with pain during palpation, function, and unassisted or assisted mandibular opening. Application of the criteria resulted in a study group of 150 patients with unilateral TMJ pain, 10 with bilateral TMJ pain, and 34 without TMJ pain. Bilateral sagittal and coronal MR images were obtained to establish the presence or absence of TMJ internal derangement or osteoarthrosis, or both.

RESULTS

A comparison of the TMJ-related data showed a significant relationship between the clinical finding of TMJ pain and the MR imaging diagnoses of TMJ internal derangement (P =.002) and TMJ osteoarthrosis (P =.004). Significant increases in risk of pain occurred with "disk displacement without reduction and osteoarthrosis" (P =.000), "disk displacement without reduction and absence of osteoarthrosis" (P =.000), and "disk displacement with reduction and osteoarthrosis" (P =.036).

CONCLUSIONS

The results suggest that TMJ-related pain is correlated with TMJ-related MR imaging diagnoses of internal derangement and osteoarthrosis. The data confirm the biological concept of "internal derangement and osteoarthrosis," yet re-emphasize that internal derangement and osteoarthrosis may not be regarded as the unique and dominant factors in the definition of TMJ pain.

Long-term outcome after treatment of temporomandibular joint osteoarthritis with exercise and manual therapy

In a previous study, exercise and manual therapy demonstrated a 90% success rate in patients with osteoarthrosis of the temporomandibular joints in the short-term. The aim of this follow-up study was to assess the long-term effect of these treatment modalities. Seventeen patients were evaluated. All patients suffered from osteoarthrosis of the temporomandibular joints with pain in the temporomandibular joint at baseline and were treated successfully in a prior short-term study. The parameters were pain at rest and at chewing, impairment in daily life, and mouth opening. At follow-up, 11 patients (65%) experienced no pain and 13 patients (76%) had no pain at rest (Fisher's Exact Test: p<0.02). Thirteen patients (76%) had a normal incisal edge clearance, and ten patients (59%) felt no impairment due to the disease (Fisher's Exact Test: p=0.01). Thirteen patients (76%), who had been treated once successfully, have not needed treatment within the three years after cessation of their therapy. Exercise therapy is an effective tool to treat osteoarthrosis of the temporomandibular joints.

High-resolution ultrasonography of the TMJ: helpful diagnostic approach for patients with TMJ disorders ?

PURPOSE

The purpose of this study was to investigate patients with a clinical diagnosis of internal derangement to determine the diagnostic value of static high resolution ultrasonography (HR-US) when compared with magnetic resonance imaging (MRI).

PATIENTS

Sixty-six patients (132 temporomandibular joints [TMJs]) with a clinical diagnosis of internal derangement were investigated by HR-US and MRI.

METHODS

MRI and HR-US investigations were performed by experienced radiologists. The sonograms were done with a real-time 12-Mhz linear-array scanner. The HR-US interpretation errors were re-evaluated retrospectively by the same radiologist knowing the MRI results by comparing these with the 'prospective' and 'retrospective' diagnoses. The prospective and retrospective diagnoses were also compared with each other.

RESULTS

Eighty-seven of the 132 TMJs had a disc displacement proved by MRI in the closed-mouth position. At maximum mouth opening, 54 TMJs had a disc displacement. The prospective interpretations showed a sensitivity and specificity of 78% each, accounting for an accuracy of 78%. At maximum mouth opening, HR-US resulted in a sensitivity of 61%, a specificity of 88% and an accuracy of 77%. The retrospective interpretations yielded a sensitivity of 90%, a specificity of 84% and an accuracy of 88% in the closed-mouth position. At maximum mouth opening, HR-US showed a sensitivity of 73%, a specificity of 95% and an accuracy of 86%.

CONCLUSION

HR-US is suitable for the detection of disc displacements in the TMJ. However, further studies may be warranted to reduce the proportion of false-positive interpretations, thereby avoiding the application of unnecessary treatment.

Magnetic resonance imaging findings of internal derangement and effusion in patients with unilateral temporomandibular joint pain

OBJECTIVES

The purpose of this study was to investigate the relationship between the presence of temporomandibular joint (TMJ) pain and the magnetic resonance (MR) imaging findings of internal derangement (ID) and effusion.

STUDY DESIGN

The study was comprised of 41 consecutive patients with TMJ pain. Criteria for including a patient were report of unilateral pain near the TMJ, with the presence of unilateral TMJ pain during palpation, function, and/or unassisted or assisted mandibular opening, and the absence of a specific clinical TMJ-related diagnosis of disk displacement with or without reduction. Bilateral sagittal and coronal MR images were obtained to establish the presence or absence of TMJ ID or effusion, or both.

RESULTS

Comparison of the TMJ side-related data showed a significant relationship between the clinical finding of TMJ pain and the MR imaging diagnoses of TMJ ID (P =.001), and TMJ effusion (P =.004). Furthermore, there was a significant relationship between the MR imaging diagnosis of TMJ ID and TMJ effusion (P =.000). Use of the kappa statistic test indicated poor diagnostic agreement between the presence of TMJ pain and the MR imaging diagnosis of TMJ ID (kappa = 0.34), TMJ effusion (kappa = 0.32), and TMJ ID and effusion (kappa = 0.27).

CONCLUSIONS

The study's findings suggest that although clinical pain is correlated with TMJ-related MR imaging findings, clinical pain in and of itself is not reliable for predicting the presence of TMJ ID or effusion, or both. Therefore, MR imaging appears to be a warranted and necessary supplement to the clinical findings.

Prevalence of cervical spinal pain in craniomandibular pain patients

It has often been suggested that patients with a craniomandibular disorder (CMD) more often suffer from a cervical spine disorder (CSD) than persons without a CMD. However, in most studies no controlled, blind design was used, and conclusions were based on differing signs and symptoms. In this study, the recognition of CMD and CSD was based upon the presence of pain. The aim of this study was to determine the prevalence of cervical spinal pain in persons with or without craniomandibular pain, using a controlled, single-blind design. From 250 persons, a standardised oral history was taken, and a physical examination of the masticatory system and the neck was performed. Three classification models were used: one based on symptoms only; a second on signs only; and a third one based on a combination of symptoms and signs. The CMD patients were also subdivided in three subgroups: patients with mainly myogenous pain; mainly arthrogenous pain; and both myogenous and arthrogenous pain. Craniomandibular pain patients more often showed cervical spinal pain than persons without craniomandibular pain, independent of the classification model used. No difference in the prevalence of cervical spinal pain was found between the three subgroups of craniomandibular pain patients.

Possible association of temporomandibular joint pain and dysfunction with a polymorphism in the serotonin transporter gene

The purpose of this study was to evaluate the relationship between temporomandibular joint pain and dysfunction and serotonin transporter (5-HTT) gene polymorphism. Forty-eight patients with temporomandibular joint pain and 111 healthy control subjects were examined. The results for the patients and control subjects were not significantly different (P >.05). The analysis of genotype distribution (homozygous for STin 2.10 genotypes of the variable-number tandem-repeat polymorphism) showed significant differences between the patients and control subjects (P =.003). ST 2.10 allele was more frequent in the patients with temporomandibular joint pain and dysfunction. In the control group, however, STin 2.12/12 genotype was significantly higher (P =.017). In the patients who were homozygous or heterozygous for variable-number tandem-repeat variants of 5-HTT STin 2.12 copies, the average scores of somatization and anger were significantly higher than those who were homozygous for STin 2.10 variant (P <.05). The patients who were homozygous for STin 2.10 genotype were also homozygous for "L" genotype (P =.019). However, this was not the condition in the control subjects. This study does not provide evidence to support the involvement of 5-HTT gene-linked polymorphic region in temporomandibular joint pain and dysfunction. Our findings indicated that only the presence of the homozygous STin 2.10 genotype of variable-number tandem-repeat is likely to play a substantial role in the genetic predisposition to temporomandibular joint pain and dysfunction and that the STin 2.12/12 genotype may have a protective role against temporomandibular joint pain and dysfunction.

Psychological distress in chronic craniomandibular and cervical spinal pain patients

Recent studies to chronic pain have shown that the number of painful body areas is related to the level of psychological distress. Therefore, the first aim of this study was to analyse differences in level of psychological distress between craniomandibular pain patients with or without cervical spinal pain. In this analysis, the number of painful body areas below the cervical spine was also taken into account. The second aim was to determine psychological differences between subgroups of craniomandibular pain patients. In this study, 103 out of 250 persons with or without craniomandibular pain were included in the final analyses. Patients who suffered from both craniomandibular and cervical spinal pain showed higher levels of psychological distress, as measured with the Symptom Checklist 90 (SCL-90) than patients with local craniomandibular pain and persons without pain. Further, a positive relationship was found between the number of painful body areas below the cervical spine, as measured on a body drawing, and the SCL-90 scores. No psychological differences were found between myogenous and arthrogenous craniomandibular pain patients. In conclusion, chronic craniomandibular pain patients with a coexistent cervical spinal pain showed more psychological distress compared to patients with only a local craniomandibular pain and asymptomatic persons.

Relationship between temporomandibular joint pain and magnetic resonance imaging findings of internal derangement

In terms of clinical decision-making in instances of temporomandibular disorders (TMD) and orofacial pain, there is controversy in the literature over the diagnostic significance of the temporomandibular joint (TMJ)-related variable disk-condyle relationship (DCR). The purpose of this study was to investigate whether in patients with TMJ-related pain, the variable of TMJ pain may be linked to magnetic resonance (MR) imaging findings of internal derangement (ID). The study comprised 163 consecutive TMJ pain patients. Criteria for including a patient were report of orofacial pain referred to the TMJ, and the presence of uni- or bilateral TMJ pain during palpation, during function, and/or during unassisted or assisted mandibular opening. Bilateral sagittal and coronal MR images were obtained to establish the prevalence of TMJ ID types. Analysis of the data revealed the presence of TMJ pain to be associated with significantly more MR imaging diagnoses of ID than an absence of ID (P<0.001), and disk displacement without reduction than disk displacement with reduction (P<0.001). Using chi-square analysis, the results showed a significant relationship between the presence of TMJ-related pain and the MR imaging diagnosis of TMJ ID (P=0.001), and TMJ ID type (P=0.000). Use of the Kappa statistical test indicated poor diagnostic agreement between the presence of TMJ pain and the MR imaging diagnosis of ID (K=0.16). The results suggest that the clinical variable of TMJ pain may have a significant effect on the prevalences of MR imaging diagnoses of TMJ ID. The data confirm the biological concept of DCR as a diagnostic approach in patients with signs and symptoms of TMJ-related pain.

Temporomandibular joint pain analgesia by linearly polarized near-infrared irradiation

OBJECTIVE

The objective of this study was to describe a pilot treatment of temporomandibular joint pain by linearly polarized near-infrared irradiation.

DESIGN

A prospective clinical study.

SETTING

University teaching hospital.

PATIENTS

Patients comprised 20 women (mean age +/- SD: 26.6 +/- 15.2 years) with unilateral temporomandibular pain. The patients had already received other conservative treatments, but temporomandibular pain did not attenuate.

INTERVENTION

Linearly polarized near-infrared irradiation with the Super Lizer was used.

RESULTS

The painless interincisal distance of the mouth opening, which is one of the objective parameters of temporomandibular dysfunction, and the visual analogue scale of the affected temporomandibular joint before treatment were 33.4 +/- 6.5 mm and 5.0 +/- 2.7 points, respectively. Pilot linearly polarized near-infrared irradiation was applied weekly to the skin areas overlying four painful points. The present treatment alleviated temporomandibular pain after the patients had received only four weekly irradiation treatments, with final measured values of the visual analogue scale being 1.4 +/- 1.6 points. The final painless mouth-opening distance increased by 7.6 +/- 4.6 mm compared with the first measured distance without complications.

CONCLUSION

This pilot treatment using the Super Lizer provided relief from temporomandibular pain over a period of 4 weeks.

Temporomandibular joint pain: relationship to internal derangement type, osteoarthrosis, and synovial fluid mediator level of tumor necrosis factor-alpha

OBJECTIVES

The purpose of this study was to investigate whether patients with temporomandibular joint (TMJ)-related pain classified as capsulitis/synovitis may be linked to magnetic resonance imaging (MRI) findings of internal derangement, osteoarthrosis, or the synovial fluid aspirate findings of tumor necrosis factor-alpha (TNF-alpha) level.

STUDY DESIGN

The study comprised 23 patients with temporomandibular disorders (TMD), who had nonchronic pain (pain onset < or =6 months) and a unilateral TMJ-related diagnosis of capsulitis/synovitis. Bilateral sagittal and coronal magnetic resonance images were obtained to establish the presence or absence of internal derangement, osteoarthrosis, or both. TMJ synovial fluid aspirates were obtained from the pain and contralateral nonpain sides to determine the TNF-alpha level.

RESULTS

Comparison of the TMJ side-related data showed a significant relationship between the clinical TMD diagnosis of capsulitis/synovitis and the MRI diagnoses of TMJ internal derangement (P =.002) and of TMJ internal derangement type (P =.04). The mean TNF-alpha level in synovial fluid aspirates from TMJs assigned a clinical TMD diagnosis of capsulitis/synovitis was significantly higher than in those obtained from contralateral nonpain sides (P =.001). There was no correlation between the clinical diagnosis of capsulitis/synovitis and the MRI diagnosis of TMJ osteoarthrosis (P =.13) or between the MRI diagnosis of TMJ osteoarthrosis and that of TMJ internal derangement (P =.70) or TMJ internal derangement type (P =.33).

CONCLUSIONS

The results suggest that the TMJ pain condition of capsulitis/synovitis is related to TMJ-side specific MRI diagnoses of internal derangement and internal derangement type, and synovial fluid aspirate findings of TNF-alpha level. The data confirm the concept of elevated mediator level as a diagnostic approach for patients presenting with TMJ-related pain. MRI and synovial fluid aspirates may be used as diagnostic methods for evaluating TMJ-related pain conditions.

Exercise therapy for craniomandibular disorders

OBJECTIVE

To evaluate the use of exercise therapy for the treatment of craniomandibular disorders (CMDs).

DESIGN

Before-after trial. All patients were assigned to a waiting list, serving as a no-treatment control period.

SETTING

Outpatient clinic for physical medicine and rehabilitation of the University of Vienna.

PATIENTS

Thirty consecutive patients suffering from CMD with anteridr disc displacement with reduction who were consulting a CMD service.

INCLUSION CRITERIA

(1) symptoms lasting at least 3 months, (2) pain in the temporomandibular region, (3) a positive axiography, and (4) evidence of postural dysfunction. Twenty-six patients completed the study; no adverse effects occurred.

INTERVENTIONS

Active and passive jaw movement exercises, correction of body posture, and relaxation techniques.

MAIN OUTCOME MEASURES

(1) Pain at rest, (2) pain at stress, (3) impairment, and (4) mouth opening at baseline, before and after treatment, and at 6-month follow-up.

RESULTS

During the control period, no changes occurred. After the treatment, pain and impairment were significantly reduced (Wilcoxon test, p < .001). Four patients had a restricted mouth opening, in contrast to 15 before treatment (chi2 test, p < .005). Joint clicking vanished in 13.3% and was reduced in another 13.3% (chi2 test, p < .01). These results did not change until follow-up. Seventy-five percent of the patients were treated successfully.

CONCLUSION

Exercise therapy seems to be useful in the treatment of anterior disc displacement with reduction.

Effect of arthrocentesis and hydraulic distension on the temporomandibular joint disk position

OBJECTIVE

Recent studies have suggested arthrocentesis and hydraulic distension as an effective treatment modality in patients demonstrating clinical findings consistent with the diagnosis of disk displacement without reduction, normal range of motion thereby being restored and pain of the temporomandibular joint reduced. In view of the fact that only a few studies have been performed to verify the biologic concept of disk displacement without reduction as a diagnostic and therapeutic approach in patients with "closed-lock" symptoms, the purpose of this study was to investigate whether temporomandibular joint-related variable disk position might be linked to cessation of related signs and symptoms associated with the performance of arthrocentesis and hydraulic distension.

STUDY DESIGN

The study compared 15 patients, each of whom was assigned a clinical unilateral temporomandibular joint-related diagnosis of internal derangement (ID) type III (disk displacement without reduction) in combination with capsulitis/synovitis. Clinical diagnoses were made according to the Clinical Diagnostic Criteria for Temporomandibular Disorders. Bilateral sagittal and coronal magnetic resonance images were obtained immediately preoperatively and at 2-month follow-up to establish the presence or absence of associated types of ID. Temporomandibular joint-related pain, level of function, and mandibular range of motion were assessed preoperatively and the data were compared with the respective 2-month follow-up findings.

RESULTS

Comparison of the pretreatment temporomandibular joint side-related data revealed the temporomandibular joint side with an ID-III in combination with capsulitis/synovitis to be associated with significantly more magnetic resonance imaging diagnoses of ID than of an absence of ID (P <.001) and with significantly more disk displacement without reduction than disk displacement with reduction (P <.001). At the 2-month follow-up, clinical evaluation showed a significant reduction in temporomandibular joint-related pain during function (P <.001), a significant reduction in the prevalence of temporomandibular joint-related diagnoses of capsulitis/synovitis (P <.001) and ID-III (P <.01), and a significant increase in mandibular range of motion (P <.01). There was no change in the prevalence rates of associated temporomandibular joint side-related IDs.

CONCLUSIONS

The results confirm the concept of disk displacement as a diagnostic approach but not as a therapeutic approach for patients presenting with signs and symptoms of unilateral ID-III in combination with capsulitis/synovitis. In terms of clinical decision-making in temporomandibular disorder-related instances of ID, magnetic resonance imaging may be used as a diagnostic method for identifying the diagnostic validity of the variable "disk-condyle relationship."

Diagnoses among referrals to a Swedish clinic specialized in temporomandibular disorders

The purpose was to describe the distribution of diagnoses among all referrals to a clinic specialized in temporomandibular disorders (TMD). A series of 1500 consecutive patients, evaluated by 1 dentist, were diagnosed according to the criteria of The International Classification of Diseases, 9th Revision, Clinical Modification: ICD-9-CM. Some referrals (12%) were never evaluated, were symptom-free, or were forwarded to other clinics. Various dental, neurogenic, occlusal, dentofacial, and other problems occurred. Vague orofacial pain was common, as was tension-type headache (6% each). More than 5% of the patients were affected by systemic disorders with manifestations in the temporomandibular joints. About half of all referrals could be strictly diagnosed with TMD. Myalgia was diagnosed as the main complaint in 19%. Internal derangement 'clicking' (15%) and 'closed lock' (6%) were more common than traumatic/ unspecified arthritis (6%) or osteoarthrosis (5%). A combination of myalgia and clicking appears to be the core sign in patients referred with TMD.

The diagnostic value of ultrasonography to determine the temporomandibular joint disk position

OBJECTIVE

Temporomandibular joint (TMJ) arthrography and magnetic resonance imaging are the imaging techniques of choice in patients presenting with signs and symptoms of TMJ disorders suggesting soft tissue pathosis. With the disadvantage of arthrography as an invasive procedure and magnetic resonance imaging posing a problem in clinical availability and cost, the purpose of this study was to determine whether ultrasonography could be used to assess the presence or absence of disk displacement in patients with TMJ disorders.

STUDY DESIGN

In 17 patients, 100 TMJ positions were investigated by static and dynamic ultrasonography to analyze the disk-condyle relationship. To compare the respective findings with those of a diagnostic method offering high accuracy, coronal and sagittal magnetic resonance imaging was carried out immediately afterwards.

RESULTS

With static ultrasonography showing a sensitivity of 0.41 and a specificity of 0.70 and dynamic ultrasonography a sensitivity of 0.31 and a specificity of 0.95, the data revealed that static and dynamic ultrasonography are marginal in detecting the presence of disk displacement, but dynamic ultrasonography is sensitive in detecting the absence of disk displacement. However, with a positive predictive value of 0.61 and a negative predictive value of 0.51 for static ultrasonography, and a positive predictive value of 0.88 and a negative predictive value of 0.55 for the dynamic technique, the results indicate that both modalities are insufficient in establishing a correct diagnosis for the presence or absence of disk displacement.

CONCLUSION

In view of the fact that dynamic ultrasonography proved to be a reliable diagnostic aid for the detection of normal disk position, the results of this study should be of further interest and encourage research in its potential uses and diagnostic capabilities.

History and evolution of TMD concepts

Historically the field of temporomandibular disorders (TMD) has been based on testimonials, clinical opinion, and blind faith rather than on science. Reparative procedures to the joints, jaws, or occlusal surfaces of the teeth to develop idealized structural relationships that may be required for dental health and function are less likely to be required for the management of chronic musculoskeletal disorders. Because of the concerns of many people today regarding professional credibility and intellectual honesty, the need for a scientific foundation to support the various belief systems is of paramount importance. In fact, therapeutic approaches for TMD are undergoing a major evolution away from the traditional mechanistic dental concepts of the past to the more current biopsychosocial medical concepts that emphasize multidisciplinary approaches. Recent advances in the understanding of pain mechanisms and management of chronic pain have improved long-term treatment outcome. The emphasis is on treatment that involves the patient in the physical and behavioral management of their own problem. The majority of patients with TMD achieve good relief of their symptoms with noninvasive, conservative therapy.

Sensitivity of patients with painful temporomandibular disorders to experimentally evoked pain

Temporomandibular disorders (TMD) represent a group of chronic painful conditions involving the muscles of mastication and the temporomandibular joint. We determined whether patients with painful TMD are more sensitive to noxious stimuli than age-matched control subjects. Fifty-two TMD patients (16 with muscle pain and 36 with combined muscle and joint pain) and 23 age-matched and gender-matched volunteers participated. Forearm thermal pain threshold and tolerance values were determined. A submaximal effort tourniquet procedure was used to evoke ischemic muscle pain. Relative to control subjects, TMD patients had significantly lower thermal pain threshold, ischemic pain threshold, and ischemic pain tolerance values; and thermal pain tolerance values also tended to be lower. Pain sensitivity did not differ between the two groups of TMD patients. Furthermore, the submaximal effort tourniquet procedure, which is capable of altering acute orofacial pain (Sigurdsson and Maixner, 1994) did not produce a consistent reduction in orofacial pain associated with TMD. We concluded that TMD patients are more sensitive to noxious stimuli than pain-free controls. These findings provide additional evidence that TMD is a psychophysiological disorder of the central nervous system which modulates emotional, physiological and neuroendocrine responses to emotional and physical stressors.

Current trends in temporomandibular joint imaging

Diagnostic imaging of the temporomandibular joint has undergone a revolutionary development during the last two decades. With advanced modalities we have been able to differentiate between different articular entities in patients with temporomandibular joint disorders. The purpose of this article is to review and discuss these modalities and their contribution to our present knowledge, with emphasis made on current trends in diagnostic temporomandibular joint imaging. The main section deals with diagnostic imaging of the subgroup of disorders with internal derangement caused by disk displacement including posttreatment imaging. Imaging of pathologic entities characterized by chronic inflammation such as rheumatoid arthritis are discussed in the second section. Finally, the potential of diagnostic imaging of infrequent conditions such as tumors is briefly reviewed. Magnetic resonance imaging has surpassed arthrography and computed tomography for the evaluation of most patients in these three subgroups. In patients who have various forms of disk displacements with or without accompanying bone abnormalities, a diagnostic accuracy of at least 90% may be achieved by oblique sagittal and coronal magnetic resonance imaging. In addition, alterations in the condylar marrow may be detected. T2-weighted magnetic resonance imaging can make a significant diagnostic contribution by demonstrating inflammatory reactions such as joint effusion and marrow edema. In the subgroup of patients with chronic inflammatory diseases, magnetic resonance imaging may also demonstrate abnormalities not shown with other imaging modalities. Disk deformation, fragmentation, and destruction may indirectly suggest the presence of synovial proliferation/pannus formation, which in selected cases may be directly depicted with intravenous gadopentetate dimeglumine. For more detailed evaluation of the bone condition and of soft tissue calcifications in joints with inflammatory diseases, tumors, or other disorders, computed tomography is the preferable imaging modality.

Differential treatment responses of TMD patients as a function of psychological characteristics

A number of studies have reported that psychological factors play a significant role in TMD. Several studies have identified subgroups of patients based on their responses to psychological assessments; however, none of these studies have reported on the clinical utility of classifications of TMD patients on these various measures. In this study, the differential response of 133 TMD patients classified within 3 psychosocial-behaviorally based subgroups to a conservative, standardized treatment was examined. The treatment consisted of the combination of an intra-oral appliance, biofeedback, and stress management. Follow-up assessments were conducted 6 months after treatment termination. The results demonstrated that overall as a group patients significantly improved and maintained improvements on physical, psychosocial, and behavioral measures (P < 0.0001). Comparisons across patient subgroups, however, revealed differential patterns of improvement on the outcome measures. Most notably, reliable change indices demonstrated that the patients classified into a subgroup characterized by the greatest degree of psychological distress (Dysfunctional) demonstrated significantly greater improvements on measures of pain intensity (P < 0.001), perceived impact of TMD symptoms on their lives (P < 0.001), depression (P < 0.01), and negative thoughts (P < 0.001), compared with groups characterized by greater interpersonal problems (Interpersonally Distressed) and those patients who appeared to be the least disabled by TMD (Adaptive Copers). These data provide support for the clinical utility of a psychosocial-behavioral classification system and suggest that in future research individualizing treatments and outcome measures based on patient characteristics may improve treatment efficacy and outcome evaluation.

Use of superoxide dismutase (SOD) in patients with temporomandibular joint dysfunction--a preliminary study

The aim of this preliminary study was to investigate and assess the effect of intra-articular injection of superoxide dismutase (SOD) in patients with temporomandibular joint (TMJ) dysfunction who had not responded to conservative therapy in a first study. Thirty joints in 29 patients were studied. The results showed that intra-articular injection of superoxide dismutase was effective in 25 joints (83%). It was concluded that intra-articular injection of superoxide dismutase may be an alternative therapy for patients with TMJ dysfunction who fail to respond to conservative treatment.

Multidimensional evaluation of craniomandibular dysfunction. II: Pain assessment

To standardize clinical history taking, a comprehensive anamnestic questionnaire was developed (Screen). Screen includes questions about: (i) pain, (ii) other symptoms of craniomandibular dysfunction (CMD), (iii) correlates of CMD, (iv) psychosocial factors, and (v) general health. The current study focuses on variables in Screen concerning pain reported somewhere in the head, neck and/or shoulders. This study was performed to assess whether subgroups of patients with signs and symptoms of CMD and a control group of dental patients with and without signs and symptoms of CMD can be characterized by differences in areas reported to be painful, in quantitative and qualitative characteristics of pain, and in factors exacerbating pain. Results indicate that several characteristics of pain as measured in Screen can be used to discriminate between: (i) subgroups of subjects with signs and/or symptoms of CMD and controls without signs or symptoms of CMD, (ii) subgroups of clinical cases and controls with signs or symptoms of CMD, and (iii) patients with CMD with mainly a myogenous component and patients with CMD with mainly an arthrogenous component. The results of logistic regression analysis indicate that four adverbs describing pain correctly classified 75% of patients with CMD-myo and patients with CMD-arthro. Differences between patients and controls are interpreted with regard to the correct classification of patients with CMD with a mainly myogenous component and patients with CMD with a mainly arthrogenous component and the subjective treatment need for CMD. Implications for further research are discussed.

Temporomandibular disorders and chronic pain: disease or illness?

Temporomandibular disorders (TMD) are examined from a biopsychosocial or illness perspective. Data are reviewed in accordance with the concept that TMD is a chronic pain condition that shares many features with other common chronic pain conditions. TMD is placed within the same biopsychosocial model currently used to study and manage all common chronic pain conditions. The concept of chronic pain dysfunction, which has emerged as a critical consideration for chronic pain research and management, is also reviewed. Most chronic pain patients seem to bear their condition adequately and thus maintain adaptive levels of psychosocial function. By contrast, a psychosocially dysfunctional segment of the chronic pain population appears unable to cope as well and demonstrate higher rates of depression, somatization, and health care use, even though persons in this segment are not different from their functional peers on the basis of observable organic pathology. Finally, data are reviewed from longitudinal, epidemiologic, and experimental intervention studies that substantiate these two perspectives.

The functional impact of extraction and nonextraction treatments: a long-term comparison in patients with "borderline," equally susceptible Class II malocclusions

Discriminant analysis was used to identify in retrospect a sample of 63 patients who had presented initially with Class II malocclusions that, according to then prevailing standards of specialty practice, could have been treated either with or without the extraction of premolars. These "borderline" subjects (33 extraction, 30 nonextraction) were then recalled for a long-term evaluation (on average, about 14 years after treatment) of the functional status of both the head and the neck musculature and the temporomandibular joints. In terms of a menu of 62 signs and symptoms (muscle palpation, joint function) that are commonly thought to be characteristic of craniomandibular disorders, there were no significant differences between the extraction and nonextraction samples. The present data therefore fail to support the popular notion that "premolar extraction causes 'TMJ'".

Anatomic basis for disk displacement in temporomandibular joint (TMJ) dysfunction

This study was designed to investigate the site of lateral pterygoid muscle insertion into the temporomandibular joint (TMJ) disk, and the relationship between that attachment and the disk displacement. One hundred and ten TM joints from 78 cadavers were collected and sectioned in the sagittal plane. Sixty-two unilateral specimens were available and 16 additional specimens were selected randomly from the remaining cadavers in which both condyles were available. Thus statistical comparisons were not confounded by autocorrelation and were based on 78 independent specimens. The sites of muscle attachment in relation to the disk were identified histologically. Of the 78 joints 49 had anterior disk displacement. Of the 42 cases with insertion directly into the disk, 30 had anterior disk displacement. In contrast, only 19 of the 36 disks without direct muscle insertion were displaced. This finding indicated a statistically significant relationship between functional muscle attachment and disk displacement (chi 2 = 9.28, df = 1, p = 0.006). However, the superior head of the lateral pterygoid muscle (SLP) may not be the precipitating factor for anterior disk displacement even though it does coordinate disk movement on closure. Since other factors (e.g., trauma) can result in disk displacement, the SLP can maintain disk displacement only when it inserts directly into the disk. In cases of normal disk arrangement and condylar attachment, the muscle may not play a clinically significant role in disk displacement because disk attachment at the medial and lateral poles of the condyle allows the disk to move freely with the condyle.(ABSTRACT TRUNCATED AT 250 WORDS)