Journal of Oral & Facial Pain and Headache, 02/2002

Aims: To evaluate the influence of the menstrual cycle on pressure- pain thresholds (PPTs) in patients with masticatory myalgia. Methods: Fluctuations in pain sensitivity during 2 consecutive menstrual cycles were assessed in 15 normally menstruating patients with a myogenous temporomandibular disorder (TMD). Muscle pain was measured by the use of pressure algometry and a visual analog scale (VAS). The McGill Pain Questionnaire was used to assess the sensory, affective, and evaluative dimensions of the pain. Results: Since 5 patients dropped out of the study due to pregnancy, unexpected menstrual cycle irregularities, or personal problems, statistical analysis was performed on 10 patients. Time had a significant influence on the pain condition. The PPTs of all muscle sites increased significantly and progressively over time by 16% to 42% in the follicular and luteal phases. PPTs remained low in the perimenstrual phase. The VAS pain rating did not correspond well with the PPTs, and the statistical analysis showed that the VAS ratings could not be used as predictors for the PPT measurements or detect the differences between cycle phases. The sensory, affective, and evaluative dimensions of the pain were significantly lower at the end of the trial. Conclusion: These data suggest a significant influence of the menstrual cycle on pain report and a nonspecific improvement of the chronic myogenous TMD. Keywords: pain threshold, menstrual cycle, masticatory muscle, myofascial pain

Aims: Whiplash injury to the neck is often considered a significant risk factor for development of temporomandibular disorders (TMD), and has been proposed to produce internal derangements of the temporomandibular joint (TMJ). Few studies, however, have examined TMD-related pain in acute whiplash patients compared with a matched control group. The aim of the present study was to assess pain and sensorimotor function in the craniofacial region in an unselected group of patients sustaining a motor vehicle accident involving a rear collision. Methods: Prospectively, 19 acute whiplash patients exposed to a motor vehicle accident involving a rear collision participated in a study of TMD. The control group consisted of 20 age- and gender-matched ankleinjury patients. Participants were seen within 4 weeks and again at 6 months post-injury. The masticatory system was examined in accordance with the research diagnostic criteria. Participants underwent structured interviews, filled out the McGill Pain Questionnaire (MPQ), and had their masticatory system examined by a trained dentist, blinded to their diagnosis. Pain detection threshold (PDT) to pressure stimuli, and maximal voluntary occlusal force (MVOF) were obtained at each visit. Results: One whiplash patient and 1 ankle-injury patient had jaw pain at the first visit. Palpation scores of the TMJ and the summated palpation scores only tended to be higher in patients sustaining a whiplash injury than in ankle- injury controls at the first visit. However, MPQ, TMD symptoms and signs, MVOF and PDT were not significantly different in whiplash-injury and ankle-injury patients after 4 weeks and 6 months. Conclusion: TMD pain after whiplash injury and ankle injury is rare, suggesting that whiplash injury is not a major risk factor for the development of TMD problems. Further studies are needed to identify which other factors may contribute to TMD pain. Keywords: whiplash injuries, bite force, pressure algometry, craniofacial pain, TMD pain

Aims: While a significant number of therapeutic models have been suggested for management of orofacial pain and limited opening in patients experiencing temporomandibular disorders (TMD), little attention has been given to the issue of routine daily care activities, such as toothbrushing and flossing. The purpose of this study was to develop an understanding of the extent to which TMD patients experience difficulty in performing routine daily mouth care. Methods: Forty patients seeking care for TMD in the Orofacial Pain Center at the University of Kentucky College of Dentistry were age- and gender-matched to a group of general dentistry patients not experiencing TMD. Participants completed a survey of oral health habits, and a clinical exam. Results: Results indicated that TMD patients felt their discomfort had created more difficulty with daily mouth care as compared with the general dentistry patients (P .000). Most TMD patients, however, continued with routine daily mouth care, except for 15% who reported an inability to floss on a regular basis. Also, a majority of TMD patients (63%) reported a change in seeking routine professional care because of their disorder (P .000). Conclusion: The present data indicate the need for TMD patients to receive information concerning routine daily mouth care and visits for professional dental care. The results are discussed in terms of the strategies that dental care providers need to develop in order to address the significant consequences of orofacial pain on regular dental care. Keywords: temporomandibular disorders, daily mouth care, toothbrushing/flossing, routine professional care, patient pain/difficulty perception

Aims: According to the Research Diagnostic Criteria (J Craniomandib Disord 1992;6(4):301-355), an anterior disc displacement with reduction (ADD) is characterized by reciprocal clicking with the opening click occurring at a mouth opening at least 5 mm greater than that of the closing click. The aim of this study was to test whether the 5-mm criterion of the RDC is characteristic for a click due to an ADD. Methods: From 30 participants with a unilateral ADD, recordings of mandibular movements with 6 degrees of freedom as well as joint sound recordings were made. The participants performed free open movements and loaded closing movements. Results: In 8 joints (27%), the 5-mm criterion was not fulfilled. For 2 participants, the click while closing occurred with an even larger mouth opening than that while opening. Recordings of the condylar movements showed that the opening clicks occurred over a broad range of the opening movement, whereas all the closing clicks occurred just before the condyle reached its terminal position in the fossa. Conclusion: The 5-mm criterion of the RDC is not characteristic of all anterior disc displacements with reduction. Keywords: temporomandibular joint, anterior disc displacement, clicking, condylar movements, recognition

Aims: To investigate whether involvement of the temporomandibular joint (TMJ) can occur in men with Reiter's disease (RD). Methods: Forty-nine men with RD and 49 individually matched (gender, age and dentition type) controls with no known general joint disease were screened for findings in the TMJ by panoramic tomography. Results: Duration of subjective symptoms (eg, pain) in the masticatory system correlated with duration of RD (P = .05). In the RD group, severity of clinical signs or symptoms correlated with the progressive form of RD (P = .01), number of affected joints (P = .0001), and involvement of the cervical (P = .0001) and lumbar spine (P = .05). Patients with RD more frequently had radiographic findings (33%) in the condyle of the TMJ than did controls (10%) (P = .002). The most characteristic radiographic sign in the condyle in the RD group was unilateral erosion (12%). Conclusion: Patients with RD often have erosion causing pain and dysfunction in the TMJ. Potential masticatory system problems for such patients should be brought to the attention of dentists and physicians. Keywords: temporomandibular joint, Reiter's disease, radiology

Aims: To determine the characteristic magnetic resonance imaging (MRI) findings of synovial chondromatosis of the temporomandibular joint (TMJ). Methods: MRI was carried out in 11 cases of synovial chondromatosis of the TMJ, which had been confirmed surgically and histologically. Results: Severe bony changes were not apparent. One or more hypointensive loose bodies were seen in 7 of the 11 cases. A considerable amount of synovial fluid, often with capsular expansion, was a common finding. Conclusion: A diagnosis of synovial chondromatosis of the TMJ must be considered when the amount of synovial fluid is abnormally large and the disc position is fairly normal, as seen on closed- and open-mouth MRI of the TMJ, without any associated severe changes in disc shape or bony structure. Keywords: synovial chondromatosis, temporomandibular joint, magnetic resonance imaging, synovial fluid, joint loose body