Journal of Oral & Facial Pain and Headache, 03/1995

The contribution of the nervous system to the pathophysiology of rheumatoid arthritis has been proposed to be mediated by certain neuropeptides. Neuropeptide Y, calcitonin gene-related peptide, substance P, and neurokinin A are considered modulators of inflammatory joint disease. Parameters of pain, as well as occlusal signs of tissue destruction from the arthritic TMJ and the corresponding neuropeptide concentrations in TMJ synovial fluid, were investigated in patients with various inflammatory jint diseases. The patients with rheumatoid arthritis were also examined in a separate diagnostic group. Visual analog scale, palpatory tenderness, maximal voluntary mouth opening, and anterior open bite were correlated to neuropeptide-like immunoreactivities of the above four neuropeptides. It was found that high concentrations of calcitonin gene-related peptide and neuropeptide Y in TMJ fluid are associated with pain, impairment of mandibular mobility, and occlusal signs of TMJ destruction in patients with rheumatoid arthritis. The results indicated neuorpeptide involvement in rheumatoid arthritis, proposing a potentiation of the symptoms and signs by the inflammatory action of calcitonin gene-related peptide and neuropeptide Y.

A systematic review was performed in response to a request the National Institute of Dental Research to evaluate in broad terms the strength of evidence regarding therapy for temporomandibular disorders (TMD). This report describes the epidemiology of research for TMD in broad terms indicating the total number of citations, the proportion related to therapy, and the distribution according to study design and language or country of origin. Medline and hand searching of article bibliographies and of selected journals produced the set of citations evaluated. From 1980 to 1992, there were more than 4,000 references to TMD, of which about 1,200 regarded therapy. Forty-one percent of the 1,200 references were classified as reviews and only 15% were clinical studies. Less than 5% (n=51) were randomized controlled trials. This review identified a vast amount of literature on TMD with articles published in several different languages, indicating a worldwide interest in this problem. Because assimiliation of this literature can not be expected of the average practitioner treating patients who have TMD, or of most researchers in this area, it is likely not being used to its maximum potential. The literature on therapy for TMD consists primarily of uncontrolled observations of patients such as uncontrolled clinical trials, case series, case reports, and simple descriptions of techniques. It is generally agreed that such uncontrolled observations, while contributing to knowledge about therapy of TMD, are subject to considerable bias and thus difficult to interpret. If treatment of TMD is going to follow the trend in medicine to base patient-care decisions on evidence rather than expert opinion or pathophsiologic rationales, then more rigorously controlled clinical trials of most therapies will be necessary.

Of a random sample of 345 subjects aged 35 years and drawn from the general population of Vasterbotten County, Sweden, 276 (80%) participaated in an epidemiologic survey on muscle tenderness of the jaw, neck, shoulder, arm, hand, and calf, and on the prevalence of signs and symptoms of craniomandibular disorders. The control group consisted of 144 subjects (52%) who had no tenderness. The remaining subjects were separated into groups: (1) 59 subjects (21%) with tenderness only in jaw muscles; (2) 26 subjects (9%) with tenderness only in neck/shoulder muscles; (3) 39 subjects (14%) with tenderness in muscles of the jaw and neck/shoulder; and (4) eight subjects (3%) with tenderness in all palpated muscles of the neck, shoulder, arm, hand, and calf. Women were found to have palpation tenderness significantly more often than men (P.05). The main finding of this study was the presence of a significantly higher proportion of signs and symptoms of craniomandibular disorders in the group who had both jaw muscle tenderness and neck/shoulder muscle tenderness and in the group who had generalized tenderness than in the control group. The results indicate that in epidemiologic and clinical research of craniomandibular disorders, a distinction between local, regional, and general tenderness should be made since the etiology may differ.

The aim of this study was to compare the provisional diagnosis based on an initial clinical examination with subsequent findings of magnetic resonance imaging in patients with internal derangement of the temporomandibular joint. Clinical examinations were conducted on 242 patients (198) women and 44 men) who had unilateral (51%) or bilateral (49%) temporomandibular joint internal derangement. They were divided into the following categories: (1) disc displacement with reduction; (2) disc displacement without reduction; (3) stuck disc; (4) degenerative arthrosis with or without one of the abuve; and (5) normal temporomandibular joint of the contralateral side. There was no statistically significant difference in the distribution of disorders on a unilateral or bilateral basis or in the prevalence of disorders in right versus left joints. Based on the high occurrence of matching true-negative data, this study showed a highly statistically significant correlation between the magnetic resonance findings and the clinical data for all categories of derangement. Despite this high correlation, the magnetic resonance imaging and clinical diagnoses matched exactly in only 287 of the 484 joints studied. There was only partial agreement in the remaining 197 joints. The best clinical diagnosis in relation to the magnetic resonance findings was observed in the arthrosis category followed by the categories of normal joint, disc displacement with reduction, stuck disc, and disc displacement without reduction, in descending order. This study strongly suggests that degenerative arthrosis is a result of a long-term displaced disc. The clinical examination alone did not correctly indicate all the structural defects; therefore, it is insufficient for determinig the status of the joiint.

Vascular heat emissions that present on the human face can provide physiologic indicators of underlying health or disease. Electronic thermography may serve as a nonionizing, noninvasive alternative for solving diagnostic problems. This study was designed to quantify normal values of vascular heat emissions of the face. Electronic thermograms were taken of 102 subjects using an Agema 870 unit, at .1 degree C accuracy, under controlled conditions. Results indicated a high degree of mean thermal symmetry about the face. Using frontal and lateral electronic thermogram projections, the mean temperatures of 25 selected right-versus-left side anatomic zones were within .1 degree C of each other. Analysis of frontally and laterally projected electronic thermograms also produced a new mapping of thermally distinct facial zones. Of greatest importance, the right-versus-left-side thermal differences ( T) between many specific facial regions for individual subjects were demonstrated to be much smaller (0.4 degrees C) than previously reported T values of the same facial regions in a wide variety of chronic disorders. These differences in T values between asymptomatic subjects and patients with various facial pain syndromes may prove to be useful thresholds for determining normal versus abnormal facial thermograms.

Dental attrition randed according to a validated sererity scale was correlated with age as a proxy for functional wear in 148 asymptomatic subjects. Anterior, posterior, mediotrusive, laterotrusive, and total attrition severity was analyzed. The geometric contribution of canine attrition to the variance of posterior attrition was also tested through correlations, and the time span required to record a statistically significant difference in attrition using the scale was determined. Age explained 12.6% of the differences in the total attrition scores (p.001, Spearman's rho), 6.4% of the anterior scores (P.01), and 20.9% of the laterotrusive scores (P.001), 6% to 36% of the mediotrusive attrition (P.05 to P.01), and 20% to 29% of the laterotrusive attrition (P.05 to P.001). At least 20 to 30 years was necessary to show significant clinical differences, except that laterotrusive attrition changes could be discriminated in only 10 years for the 20- to 29-year-old group. Notable attrition was already evident in the 20-to 29-year-olds, and acelerated wear rates prior to age 20 years were not maintained in most areas of the dentition. A nonlinear progression with age was observed, thereby inhibiting prediction of subsequent attrition from prior levels. Attrition was concluded to have multifactorail etiology, with age and the geometry of canine guidance having a significant influence, in addition to commonly accepted parafunction.

Indomethacin-responsive headaches can present in the orofacial region. According to the classification of headache by the International Headache Society, indomethacin-responsive headaches include chronic paroxysmal hemicrania, hemicrania continua, benign cough headache, benign exertional headache, and sharp, short-lived headache pain syndrome. The mechanism by which indomethacin produces its therapeutic effects in these headache disorders remains speculative. A review of indomethacin-responsive orofacial pain are reported. Because these headache disorders are rare but may present as facial pain, they should be considered in the differential diagnosis of orofacial pain. A comprehensive evaluation prior to performing irreversible teatments is essential when an idiopathic facial pain presents to the dental clinician.

This case report describes the experience of a 26-year-old woman who underwent multiple jaw surgeries. An initial 22 months of unsuccessful nonsurgical therapy was followed by a 7-year period during which the following were performed: 12 surgeries of her right temporomandibular joint; one surgery of her left temporomandibular joint; bilateral coronoidectomies; one surgery of her right mandible; and three surgeries of her left mandible. This case is important because although the existence of multiple jaw surgery cases are widely noted throughout the literature, this is the first case report that presents in-depth prospective documentation.