Journal of Oral & Facial Pain and Headache, 04/1993

Longitudinal variations of subjective symptoms and clinical signs of craniomandibular disorders, orofacial parafunctions, and occlusal conditions were examined in 131 Finnish adolescents. Patients were interviewed and clinically examined at the ages of 14, 15, and 18 years. Signs and symptoms of craniomandibular disorders were common, although usually mild. Reported and recorded temporomandibular clicking sounds were the most frequent findings and increased with age. They showed, however, no predictable pattern, and only a few patients consistently reported clicking sounds or had them recorded. Although the frequency of craniomandibular disorders according to Helkimo's clinical dysfunction index was high at each examination, there also was great intraindividual fluctuation longitudinally; impairment and improvement occurred almost equally often, showing no predictable pattern. Only 3% of those tested consistently had an index value of more than I. Thus, even longer follow-up studies are needed to understand natural longitudinal variations and evaluate the need and demand for treatment of craniomandibular disorder.

One hundred ten patients complaining of nondental orofacial pain of more than 3 months' duration were psychologically evaluated with the Minnesota Multiphasic Personality Inventory. Four distinct personality profiles were found: psychophysiologic reaction, in 52% of the patients; depressed reaction, in 11% of the patients; defensive reaction, in 12% of the patients; and o diagnosis (normal), in 24% of the patients. These results indicate that chronic temporomandibular pain patients present personality characteristics that are similar to those of other chronic pain patients according to the Minnesota Multiphasic Personality Inventory. The diagnostic and therapeutic implications of each profile are reviewed and discussed in terms of a medical model of temporomandibular disorders.

This study assessed the use of electronic thermography in the thermal image characterization of 20 patients with osteoarthrosis of the temporomandibular joint as proven by radiographic detection of bone erosions. Thermal assessments included: pattern recognition, pattern symmetry, absolute temperature, delta T measurements, and mean temperature measurements and differences within five designated anatomic zones. In patients with osteoarthrosis of the temporomandibular joint, results demonstrated some characteristically abnormal thermal patterns; low levels of thermal symmetry; and substantially elevated absolute temperature measurements, mean temperature zone measurements, and delta T values. These observations suggest that electronic thermography may prove to be clinically useful as a diagnostic method of assessing temporomandibular joint disorders, particularly osteoarthrosis. However, more extensive studies are needed before thermographic evaluation of the temporomandibular joint will be accepted clinically.

This study compared the stress reports of Finnish craniomandibular disorder patients and nonpatients by using the Symptoms of Stress Inventory as a screening device. A comparison of Finnish and American craniomandibular disorder patients' stress reports was made in the same manner. The overall stress level of craniomandibular disorder patients was higher than that of nonpatients. The patients had elevated scores on somatic subscales, with muscle tension symptoms being the most characteristic. These results are in accordance with American results. However, statistically significant differences were not found for emotional symptoms.

A sample of 6718 healthy persons were asked, during an examination in connection with getting a job, whether they had noticed sounds emanating from their temporomandibular joints. A total of 20.1% of the job applicants reported hearing joint sounds. Crepitation or clicking was found in more than 12.2% of the sample on palpation. Auscultatory examination revealed sounds in almost 72.5% of the individuals. When examined with a phonocardiograph, 84% of a randomly selected subgroup demonstrated joint sounds. Considering the frequency with which this symptom occurred in healthy individuals, caution must be exercised in interpreting joint sounds as definite proof of arthropathy.

A group of 99 children and young adults referred to a Swedish oral health sciences center were retrospectively evaluated regarding symptoms, signs, diagnoses, treatment, and treatment outcome. The most common symptoms in this patient group were headaches (52%), temporomandibular joint clicking (49%), pain at chewing (47%), and pain at wide mouth opening (46%). Common diagnoses were anterior disc displacement (32%) and craniomandibular disorders of muscular origin (16%). After treatment, 91% of the children and young adults reported themselves to be better or free of symptoms. A treatment modality often used was the occlusal splint, and it was concluded that using conservative methods led to good treatment outcomes in this patient group.

This study examined the relationship between hypothalamically elicited emotional behaviors and electromyographic activity in the masseter muscle of the cat. Electromyographic amplitudes resulting from stimulation at hypothalamic sites at which affective defense and quiet biting attack behaviors were elicited were compared with those recorded during stick biting that simulated mastication. The electromyographic activity elicited by hypothalamic stimulation was greater than that found from stick biting for all behavioral sites. At control sites, from which no behavior could be elicited, the electromyographic activity associated with stick biting exceeded that observed from the hypothalamic sites. These findings suggest a relationship between hypothalamically elicited behaviors and increased levels of jaw muscle activity.

Nocturnal clenching and grinding can be recorded with a portable electromyograph unit and a standard cassette tape recorder, which registers the clenching episodes on a cassette tape. The information can then be coded by a new instrument, called a Pulse Identifier, that subsequently transfers the data to a polygraph chart recorder. This study evaluated the reliability and validity of the Pulse Identifier when interfaced with other instruments that measure nocturnal clenching/grinding. A known number of clenching incidents over a baseline period of time were evaluated by three lind scores. The results demonstrated an interscorer reliability coefficient of 0.99 and a validity coefficient of 0.99.

The purpose of this study was to determine if a sample of patients with internal derangement of the temporomandibular joint had a significantly greater amount of forward head posture than did an age- and gender-matched control group. Twenty-two patients at a single head, neck, and temporomandibular joint treatment center, who had the diagnosis of internal derangement of the temporomandibular joint, were compared with a control group of volunteers. The angle of each patient's head position was measured from four photographs (two of the patient sitting and two of the patient standing) with a diagonal line drawn from the spinous process of the seventh cervical vertebra to the tragus of the ear and a horizontal line drawn perpendicular to a plumb line suspended from the ceiling. The angles measured from each of the four photographs were averaged, and this figure was paired with that generated from an age- and gender-matched person in the control group. Results indicated that there was not a significantly greater degree of forward head posture in the experimental group.

Temporomandibular joints with normal and abnormal disc positions, obtained from 15 females and 38 males (most between 15 and 50 years of age), were examined under a light microscope. Histologic changes attributed to degeneration and remodeling of the articular tissues were graded according to their prominence and extension along the articular surfaces. These changes seemed little affected by internal derangement in the condyle and the temporal component. In contrast, degeneration and regressive remodeling of the disc and, although to a much lesser degree, its attachments were more severe and increased more steeply with age in internally deranged as compared to normal joints. The present findings suggest that the disc indeed suffers from an abnormal position. However, this conclusion seems tenable only for adults, as rather prominent progressive remodeling changes have been observed in joints from adolescents, but no significant degenerative variations were noted.

Following the guidelines of the Craniomandibular Index, 23 chronic patients had 42 muscle and temporomandibular joint sites palpated. Two- and four-point scales were generated in response to the patient's reactions. After 6 weeks of treatment, patients measured with the 2-point scale showed 6.39% improvement in muscle tenderness and patients measured with the 4-point scale showed a 14.99% improvement. These changes were significantly different. Correlation between scales was r = .88 originally and increased to r = .91 after 6 weeks. Results showed that the 4-point scale is significantly more able to detect clinical changes in muscle and joint tenderness than is the 2-point scale.