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[High dosage intravenous gamma globulin therapy in juvenile dermatomyositis].

In the last few years high-dose intravenous therapy with gammaglobulin in juvenile dermatomyositis with steroid resistant myopathy has been discussed as an alternative to cytostatic therapy. The 12-year-old Filipinogirl suffered from dermatomyositis with pronounced weakness of the limbs and masticatory muscles; creatinine-kinase was increased 22-fold. After 5 weeks of therapy with prednisolone (1.5 mg/kg body/weight/daily), the creatinine kinase decreased to sixfold of its standard value; the muscular weakness, however, progressed to almost complete paralysis of the scapular abductors and rotators and the coxofemoral flectors and rotators. Additional therapy with gammaglobulin at a dose of 1 g/kg body weight on two consecutive days at 4-week intervals led to complete restoration of muscular strength, normalization of muscle enzymes, and stabilization of these results after 12 courses of gammaglobulin and discontinuation of the steroid medication after 8 courses. This observation suggests that high-dose intravenous application of gammaglobulin represents an efficient therapy with minimal side effects in steroid-resistant juvenile dermatomyositis.

Biopsy↗

[Otalgia and tinnitus in patients with craniomandibular dysfunctions].

AIMS OF THE STUDY: The high prevalence of ear, nose, and throat symptoms in patients with craniomandibular disorders seems to depend on the connection between both phenomena. The present study evaluates the connection between craniomandibular disorders (CMD) and otalgia or tinnitus, investigates the correlation between specific diagnoses of CMD with otalgia or tinnitus, and estimates the effects of treatment of CMD on these ear symptoms. PATIENTS AND METHODS: The information from case histories, clinical examinations, and treatment results of 221 patients with CMD were coded and evaluated by computer. All patients received conservative treatment with occlusal splints, training in self-observation of parafunction, massage of the masticatory muscles, and heat therapy. At least 1 year after the first examination, all patients were reevaluated. According to their complaints, the patients could be divided into three groups: (1) CMD patients without ear symptoms (n = 134 = 61%), (2) CMD patients with otalgia (n = 80 = 37%), and (3) CMD patients with tinnitus (n = 8 = 3.8%) (one patient with tinnitus and otalgia). RESULTS: Otalgia correlated significantly with CMD and the specific CMD diagnoses of anterior disk displacement (ADD) without reduction and osteoarthrosis. Of the reevaluated patients with otalgia, 90% had no ear pain and 10% reported reduced or less frequent ear pain. Only one of the eight cases with tinnitus noted reduced noises; the remaining seven perceived no influence on their ear noises from therapy. CONCLUSIONS: Due to the treatment results, otalgia has to be interpreted as a possible symptom of CMD and not as a separate diagnosis.

Adult↗

Response of human jaw muscles to axial stimulation of a molar tooth.

The reflexes of the main jaw-closer muscles (masseter and anterior temporalis) on both sides of the jaw were investigated using surface electromyography to observe reflex activity following mechanical stimulation of the 1st right upper-molar tooth at various forces under a number of levels of jaw-muscle activity. As with analogous studies performed on the incisor, three distinct reflex events were identified in the EMG before the earliest conscious subject reaction: early excitation, inhibition and late excitation. However, contrary to observations found during studies on the incisor, excitation, not inhibition was the primary reflex response. The application of a local anaesthetic block around the stimulated molar showed that the primary agents in eliciting the observed reflexes were not contained within the periodontium of the stimulated tooth. A diminished representation of periodontal mechanoreceptors around the molar teeth and more elaborate root structures, hence a more solid connection to the jaw and consequently less tooth movement, were deemed the likely reason for the distinction between the reflex responses of the incisal and molar regions. In addition to the reflex studies, the minimum reaction time of a number of subjects was determined to permit the distinction of a reflex event and an event that could be a conscious subject reaction. It was found that the reaction time of the temporalis muscles was significantly shorter than those of the masseter, while no significant difference was found between the left and right sides. Overall, the data showed that the presence or absence of background muscle activity and subject variability were the main causes of changes in the reflex response, provided the level of the stimulus was greater than 3 N. The application of local anaesthetic had no impact on the reflexes evoked.

Adolescent↗

Perceptual distortion of face deletion by local anaesthesia of the human lips and teeth.

As visual guidance of facial movements is impossible, accurate movements for speech and mastication require an established body image that is formed via the information from mechanoreceptors in the skin, mucosa, periodontium, and proprioceptors in the facial and masticatory muscles and in the jaw joints. In this study we aimed to investigate how the acute deafferentation of lips and teeth alters the established image of lips, teeth and the thumb. We used a psychophysical method to determine whether the perceived sizes of the upper lip and front teeth change when the sensory input from the lips and front teeth is fully blocked. We also examined the perceived size of the thumb to test for acute interactions between the thumb and facial structures. Local anaesthetic blocking of upper lip and upper front teeth significantly increased the perceived size of the upper lip by as much as 100% (range 21-100%) in ten out of eleven subjects tested (overall mean 52%; p=0.001). The perceived size of the upper teeth also significantly increased by as much as 155% (range 30-155%) in eight of the eleven subjects during anaesthesia (overall mean 41%; p=0.035). When the region of anaesthesia was increased and both upper and lower teeth and lips were anaesthetised, the perceived size of the upper lip again increased, by 53% (p=0.040), but the change in perceived size of the upper front teeth (18%) was not significant (p=0.206). In both studies there was no change in perceived size of the thumb. The results illustrate the labile central interaction between sensory inputs and the importance of feedback from peripheral afferents in generating the subjective facial image. The timing, level, and area of anaesthesia may be important modifiers of these interactions.

Adolescent↗

Coexistence of fibromyalgia, temporomandibular disorder, and masticatory myofascial pain syndromes.

The purpose of this study was to determine the association of fibromyalgia (FM) with temporomandibular disorder (TMD) and masticatory myofascial pain (MMP). Thirty-one consecutive women diagnosed as having FM according to American College of Rheumatology criteria and 21 consecutive women diagnosed as having TMD were included in this prospective study. All patients were examined by a dentist and a physiatrist to identify the coexistence of FM and TMD. In the FM group, TMD was found in 25 (80%) patients, and only 6 (19%) patients had arthrogenous origin with MMP, whereas 19 (81%) patients had only MMP without arthrogeonous orgin of those 25 women exhibited TMD. In the TMD group, the prevalence of FM was 52%, which was significantly higher in those with TMD of arthrogenous origin with MMP. Our results indicate that coexistence of FM and TMD with MMP is high. Pain and tenderness in the masticatory muscles appear to be an important element in FM, so in some patients it may be the leading complaint.

Adolescent↗

Recurrence of non-Hodgkin's lymphoma isolated to the right masticator and left psoas muscles.

We present the clinical and magnetic resonance imaging findings of a patient who, following treatment for pancreatic non-Hodgkin's lymphoma (NHL), relapsed with apparently isolated involvement of the right masticator space and left psoas muscles. Non-Hodgkin's lymphoma arising from the masticator space muscles is very rare. In addition, simultaneous lymphomatous involvement of multiple discrete skeletal muscle sites, in the absence of disease elsewhere, has previously only been reported in the limb or limb girdle muscles. Lymphoma should be considered as a cause of isolated enlarged skeletal muscles, even when involving such distant sites.

Female↗

Altered control of submaximal bite force during bruxism in humans.

The control of bite force during varying submaximal loads was examined in patients suffering from bruxism compared to healthy humans not showing these symptoms. The subjects raised a bar (preload) with their incisor teeth and held it between their upper and lower incisors using the minimal bite force required to keep the bar in a horizontal position. Further loading was added during the preload phase. A sham load was also used. Depending on the session, the teeth were loaded by the experimenter or the subject and in one session the subject did not see the load (no visual feedback). The bite force was measured continuously using a calibrated force transducer. In all the subjects, the bite force increased with increasing load. Following the addition of the load, the level of the tonic bite force was reached rapidly with no marked overshoot. The patients with bruxism used significantly higher bite forces to hold the submaximal loads compared to the control subjects. In the control subjects, the holding forces for each submaximal load were identical in the men and the women and were independent of subject maximal bite force. Sham loading evoked no marked responses in biting force. Whether the subject or the experimenter added the load or whether the subject had visual feedback or not were not significant factors in determining the level of bite force. The results indicated that the patients with bruxism used excessively large biting forces for each given submaximal load. This study showed no evidence that the inappropriate control of bite force by patients with bruxism was due to an abnormality in the higher cortical circuits that regulates the function of trigeminal motoneurons in the brainstem. This was shown by a lack of abnormality in coordination of voluntary hand movement with biting force, a lack of abnormal anticipation response to a sham load and a lack of any effect of visual feedback. The results were in line with the hypothesis that afferent input from oral (periodontal or masticatory muscle) tissues does not provide an appropriate control of motor command in bruxism.

Adult↗

[Recommendations for the standardized evaluation and classification of painful temporomandibular disorders: an update].

BACKGROUND: In 2000, the interdisciplinary Working Group of Orofacial Pain within the German Chapter of the IASP (German Association for the Study of Pain) published recommendations for the standardized evaluation and diagnostic classification of patients with painful masticatory muscles and/or temporomandibular joints. The purpose of the present study was to critically review and update these recommendations. RESULTS: Appraisal of the relevant literature published after the release of the recommendations (up to December 2005) shows that the two-axis approach for the assessment of the somatic and psychosocial parameters of the orofacial pain experience has found wide support. Single aspects of the recommendations have been substantiated by additional scientific evidence. CONCLUSIONS: The recommendations reflect the current state of pain medicine. Therefore, they should be considered among practitioners who diagnose and manage patients suffering from temporomandibular disorders.

Germany↗

Oral acupuncture in the therapy of craniomandibular dysfunction syndrome -- a randomized controlled trial.

CONTEXT: Patients with disorders of the stomatognathic system describe pain and clicking phenomena as primary symptoms. Rapid improvement of the pain is required to ensure and maintain adequate patient compliance. OBJECTIVE: The study was intended to assess the effects of acupuncture in patients with temporomandibular disorders as compared to placebo therapy (sham laser); the primary target parameter was the subjective pain sensation. DESIGN: Randomized, placebo-controlled trial. PATIENTS AND METHODS: 23 patients were enrolled and randomly assigned to one of the two groups. One group received acupuncture treatment according to the very-point technique, the other group received sham laser treatment. The following observer-blinded findings were evaluated before and after treatment: subjective pain, mouth opening, and muscular tenderness and pain on pressure. In addition, mandibular joint movement pathways were recorded using electronic axiography. OUTCOMES: Improvements in pain scores (scale, 0-100) in the acupuncture group (19.1 +/- 11.9) were significant (p = 0.03) versus those in the placebo group (6.2 +/- 14.8). Mouth opening showed an insignificant trend towards improvement (p > 0.1) in the acupuncture (5.0 +/- 6.2 mm) versus the placebo group (1.0 +/- 4.7 mm), differences in tenderness and pain on pressure in neck and masticatory muscles were significant (p < 0,05) for most of the muscles having shown pretreatment tenderness or pain. The axiographic tracings were assessed for quality, symmetry and curve characteristics. Recordings of the opening and closing movement in the acupuncture group showed an increased frequency of improvements of curve characteristics as compared to the placebo group. The acupuncture group also showed an increased frequency of improvement in protrusion and retrusion movements, though no statistical significance could be obtained. CONCLUSION: On the basis of the results of the present study, acupuncture may be recommended as acute treatment of craniomandibular disorders, but studies with larger numbers of patients as well as about long-term treatment outcomes should be conducted.

Acupuncture Therapy↗

[Metallic condylar head prostheses to replace the temporomandibular joint].

BACKGROUND: Up to now the results after condylar reconstruction of the mandible have been regarded as less than satisfactory. PURPOSE: Functional and aesthetic long-term results after condylar head resection in traumatic and tumour cases with or without replacement by a metallic condylar head prosthesis were compared in a retrospective study. PATIENTS AND METHODS: From 1980 to 2001, 23 temporomandibular joints of 19 patients were reconstructed with metallic condylar head prostheses. The resected region, the contralateral joint, facial and masticatory muscles and the dental system were clinically and radiographically monitored for a mean period of 4 years and 9 months. Seven patients who underwent condylar resection without substitution were observed over an average follow-up time of 7 years and 11 months. RESULTS: Patients who underwent condylar resection without substitution reported more trouble with eating and speaking for a long time. TMJ endoprostheses preserved facial symmetry better. Maximum mandibular opening as well as lateral and protrusive excursions were slightly reduced in comparison with both unaffected controls and patients who underwent condylar resection without substitution. In this study bilateral condylar prostheses exhibited the same functional and aesthetic results as unilateral arthroplasty. CONCLUSIONS: Metallic condylar head prostheses originally developed for temporary replacement worked in some cases as long-term joint replacement but were not able to reach the total functional quality of natural temporomandibular joints.

Bone Plates↗

Efficacy of biofeedback-based treatments for temporomandibular disorders.

Bibliographic searches identified 14 controlled and uncontrolled outcome evaluations of biofeedback-based treatments for temporomandibular disorders published since 1978. This literature includes two randomized controlled trials (RCTs) of each of three types of biofeedback treatment: (1) surface electromyographic (SEMG) training of the masticatory muscles, (2) SEMG training combined with adjunctive cognitive-behavioral therapy (CBT) techniques, and (3) biofeedback-assisted relaxation training (BART). A detailed review of these six RCTs, supplemented with information from non-RCT findings, was conducted to determine the extent to which each type of intervention met treatment efficacy criteria promulgated by the Association for Applied Psychophysiology and Biofeedback (AAPB). We conclude that SEMG training with adjunctive CBT is an efficacious treatment for temporomandibular disorders and that both SEMG training as the sole intervention and BART are probably efficacious treatments. We discuss guidelines for designing and reporting research in this area and suggest possible directions for future studies.

Biofeedback, Psychology↗

Nonpharmacologic approaches to the management of myofascial temporomandibular disorders.

The temporomandibular disorders (TMDs) are a heterogeneous group of painful musculoskeletal conditions that include masticatory muscle pain. TMD is a common condition but its etiology is, as yet, poorly understood. Although TMD can be quite disabling, most patients presenting with symptoms improve regardless of treatment type. This article focuses on nonpharmacologic treatments for TMD; recent articles on etiology, assessment, and treatment for this muscle pain condition are reviewed. Psychological approaches include biofeedback, minimal therapist contact interventions, relaxation, and cognitive-behavioral therapy. We suggest that treatments based on the biopsychosocial model of illness should be used concurrently with treatments focusing only on the biomedical aspects of TMD. Psychological treatments need not be viewed as a treatment of last resort, but rather should be delivered concurrent with biomedical treatments. We present data from recent clinical trials showing that treatment-matching approaches tailoring psychological and educational treatments to psychosocial profiles, delivered concurrent with usual dental care, results in greater and more sustained improvement than usual dental care alone. As such, treatment for TMD should be viewed in much the same way as treatment for most other chronic pain conditions, that is, from a multidisciplinary perspective.

Behavior Therapy↗

Jaw muscle silent periods before and after rapid palatal expansion.

1. The electromyographic silent period was observed in jaw-closing muscles during a maximal clench following a tap to the mandibular symphysis in eight subjects before and after rapid palatal expansion. 2. No differences in mean silent period duration were observed among the three jaw-closing muscles examined. 3. A large (r = 0.96) and statistically significant (p less than 0.01) correlation coefficient between two sets of silent period durations at one session indicates that these measurements are repeatable and reliable. 4. The mean silent period duration for the eight patients with malocclusions was 33.5 msec. prior to rapid palatal expansion and 51.2 msec. after the completion of palatal expansion. The difference was statistically significant (p less than 0.01) and represents a 61 percent increase. 5. Patients with symptoms of TMJ dysfunction are not the only group showing a prolonged silent period duration.

Adolescent↗

Tongue and jaw muscle activity in response to mandibular rotations in a sample of normal and anterior open-bite subjects.

In order to investigate the effect of mandibular rotations in human subjects, the electromyographic activity from the left GG, left masseter, and left orbicularis oris muscles was recorded during voluntary opening movements of the mandible that were monitored by an electronic transducer. For each muscle, a computer-based system was used to calculate a threshold incisor-separation position corresponding to a 20 percent increase in base line muscle activity. The mean threshold level for the GG muscle in a sample of twenty subjects with normal occlusions was 53.0 percent (S.D. +/- 22.8)of maximum jaw opening. By contrast, a sample of nine subjects with anterior open-bite malocclusions had a statistically significant (p less than 0.001) lower mean threshold of 5.9 percent (S.D. +/- 4.5) of maximum jaw opening. No significant differences in masseter or orbicularis oris muscle activity were found between the two samples. Since postural tongue activity could play an important role in the development of the anterior dentition, the lower threshold for the GG muscle activity in response to jaw opening in anterior open-bite subjects may be of significant clinical importance.

Adolescent↗

Biomechanics of differences in lower facial height.

A two-dimensional model which allows calculation of mechanical advantage of the human temporalis and masseter muscles is presented. The model is manipulated to demonstrate how selected differences in facial morphology affect the mechanical advantage of the muscles. The model is then used to evaluate the differences in mechanical advantage between patients with the long face syndrome and those with the short face syndrome. Differences in facial morphology between these two groups result in significant differences in the mechanical advantages of their muscles. Mechanical advantage may, in part, explain observed differences in bite force between the two groups. The model suggests that some surgical procedures used to correct facial disharmonies may have a significant effect on the mechanical advantage of the jaw muscles.

Adolescent↗

The dependence of mandibular dysfunction in children on functional and morphologic malocclusion.

The influence of dental status, occlusal interference, occlusal anomalies, and general background variables on bruxism and subjective symptoms and clinical signs of mandibular dysfunction has been studied in children. Three samples of children, aged 7, 11, and 15 years, were included. The interrelations were analyzed by rank-correlation and stepwise multiple regression. In the rank-correlation analyses, dental wear and age were significantly correlated to all of the dysfunction variables. Bruxism (reported by the subjects) was not found to be significantly correlated to any of the independent variables in the regression analysis. Subjective symptoms of dysfunction could be explained to a small extent by the independent variables, of which dental wear and sucking habits were found to be the most important. Recurrent headache was, to a certain extent, dependent upon age and sex. TMJ clicking was positively correlated with dental wear and unilateral contact in the retruded contact position but was most influenced by age and sex; TMJ clicking increased with age and was more common in girls than in boys. The clinical dysfunction index of Helkimo and tenderness of the masticatory muscles on palpation were explainable, although to a minor degree, by the influence of a combination of age, occlusal interference, motor activity, and psychological factors. Functional malocclusion (occlusal interference) is more important than morphologic malocclusion in explaining the existence of mandibular dysfunction. Nevertheless, morphologic malocclusion such as Class II and Class III occlusion, frontal open-bite, and cross-bite, when associated with functional malocclusion, may create a predisposition to mandibular dysfunction. The study confirms the multifactorial etiology of mandibular dysfunction.

Adolescent↗

Associations between anterior temporal, masseter, and orbicularis oris muscle activity and craniofacial morphology in children.

In a sample of children with Class I (n = 18), Class II, Division 1 (n = 25) and Class II, Division 2 (n = 12) malocclusions, the relationship between jaw muscle activity and specific craniofacial variables has been quantified. Muscle data were obtained from the temporal, masseter, and orbicularis oris muscles at rest, in maximum intercuspation, and during clenching, jaw opening, and swallowing. Contrasts in means of the three skeletal groups identified differences in both the craniofacial and muscle variables. Orbicularis oris muscle amplitude was greater at rest and in maximum intercuspation in Class II, Division 2 subjects. Anterior temporal amplitude during clenching was significantly lower in Class II, Division 1 subjects. A principal component analysis reduced the data base, and three canonical correlations were identified at the 0.05 level of significance. Significant canonical correlations could not be found between the cephalometric data and clench, swallow, or jaw-opening tasks, which suggests no dependency between these factors. Two canonical correlations were found for the rest position data. A linear combination of masseter and orbicularis oris activity and incisor separation was correlated (r1 = 0.758) with a linear combination of mandibular unit length, upper and lower central incisor angulation, and SNOP. The second rest canonical correlation (r2 = 0.733) involved the anterior temporal muscle and a series of sixteen cephalometric variables. For the maximum intercuspation data, orbicularis oris amplitude was correlated with a linear combination of upper incisor angulation and SNOP variables (r1 = 0.727). The multivariate statistical analysis extracted a clinically significant association between orbicularis oris muscle activity and incisor position.

Cephalometry↗