Journal of Oral & Facial Pain and Headache, 04/2003

Aims: To carry out a systematic review of previous studies to determine the effectiveness of any intervention vs placebo for relief of symptoms and improvement in quality of life of patients with burning mouth syndrome (BMS) and to assess the quality of the studies. Methods: Electronic databases, conference proceedings, and bibliographies of identified publications were searched (up to September 2001) to identify relevant literature, irrespective of language of publication. Randomized controlled trials and controlled clinical trials of interventions used for the treatment of BMS in comparison to a placebo were included. The primary outcome was relief of burning/discomfort. The screening of studies, validity assessment, and data extraction were undertaken independently and in duplicate. Since statistical pooling of data was inappropriate, a qualitative assessment was undertaken. Results: Seven trials, evaluating antidepressants, cognitive behavioral therapy, analgesics, hormone replacement therapy, and vitamin complexes, met the inclusion criteria. None of the trials was able to provide conclusive evidence of effectiveness. However, cognitive behavioral therapy may be beneficial in reducing the intensity of the symptoms. Conclusion: Given that the research evidence is, as yet, unable to provide clear, conclusive evidence of an effective intervention, clinicians need to provide support and understanding when dealing with BMS sufferers. Psychological interventions that help patients to cope with symptoms may be of some use, but promising and new approaches to treatment still need to be evaluated in good-quality randomized controlled trials. Keywords: burning mouth syndrome, randomized controlled trials, systematic review

Aims: To carry out a systematic review of the literature in order to assess the pain-relieving effect and safety of pharmacologic interventions in the treatment of chronic temporomandibular disorders (TMD), including rheumatoid arthritis (RA), as well as atypical facial pain (AFP), and burning mouth syndrome (BMS). Methods: Study selection was based on randomized clinical trials (RCTs). Inclusion criteria included studies on adult patients (>= 18 years) with TMD, RA of the temporomandibular joint (TMJ), AFP, or BMS and a pain duration of > 3 months. Data sources included Medline, Cochrane Library, Embase, and PsychLitt. Results: Eleven studies with a total of 368 patients met the inclusion criteria. Four trials were on TMD patients, 2 on AFP, 1 on BMS, 1 on RA of the TMJ, and 3 on mixed groups of patients with TMD and AFP. Of the latter, amitriptyline was effective in 1 study and benzodiazepine in 2 studies; the effect in 1 of the benzodiazepine studies was improved when ibuprofen was also given. One study showed that intra-articular injection with glucocorticoid relieved the pain of RA of the TMJ. In 1 study, a combination of paracetamol, codeine, and doxylamine was effective in reducing TMD pain. No effective pharmacologic treatment was found for BMS. Only minor adverse effects were reported in the studies. Conclusion: The common use of analgesics in TMD, AFP, and BMS is not supported by scientific evidence. More large RCTs are needed to determine which pharmacologic interventions are effective in TMD, AFP, and BMS. Keywords: orofacial pain, pharmacologic treatment, randomized clinical trials, systematic review, temporomandibular disorders

Aims: To apply the Finnish version of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) Axis I to assess the occurrence of symptoms, signs, and specific subgroups of TMD, and to study the associations between the most common diagnoses and categoric demographic characteristics (gender, age group, marital status, type of work). Methods: All 30- to 55-yearold employees of the Finnish Broadcasting Company with at least 5 years at their current employment received postal questionnaires (n = 1784). Of the 1339 respondents (75%), a randomly selected one fifth were clinically examined according to the RDC/TMD Axis I (n = 241, males 48%). Results: Pain symptoms in the face or jaw regions were perceived by 14.9% and pain with 1 or more jaw movements by 9.1%. Diagnoses by the RDC/TMD criteria were: Group I: myofascial pain in 12.9%, myofascial pain with limited opening in 0.4%; Group II: disc displacement with reduction in the right temporomandibular joint (TMJ) in 9.1% and in the left TMJ in 10.8%; Group III: arthralgia in 0.4% and 0.8%, osteoarthritis in 0% and 0.4%, and osteoarthrosis in 1.2% and 1.2%, respectively, in the right and left TMJs. The most common diagnoses were found more often among women than among men. No TMD diagnosis based on the RDC/TMD was obtained in 73% of the subjects. Conclusion: The RDC/TMD appear to be of benefit in diagnosing TMD among these multiprofessional media personnel and thus may be suggested for use among nonpatient populations. Keywords: nonpatient, prevalence, RDC/TMD, temporomandibular disorders, working population

Aims: To compare jaw-stretch reflex responses in male and female subjects and to determine whether injection of glutamate into the masseter muscle facilitates these responses in both sexes. Methods: Jaw-stretch reflex responses were evoked with a muscle stretcher, and pain intensity was scored by 11 men and 13 women before and after the injection of glutamate (1.0 mol/L, 0.2 ml) into the masseter muscle. The subjects rated glutumate-evoked pain intensity on a visual analog scale. Results: Baseline jaw-stretch reflex responses were larger and glutamate injections into the masseter muscle were significantly more painful in women than in men, however, glutamate significantly facilitated jaw-stretch reflex responses in men but not in women. Conclusion: These results suggest that there is a significant sex-related difference in human jaw-stretch reflex responses and their modulation by painful stimuli. Since one possible function of facilitated jaw-stretch reflex responses during jaw muscle pain may be to reduce jaw mobility and thus protect against further exacerbation of an existing injury, the finding of a sex-related difference in modulation of jaw-stretch reflex responses may prove to be important in clarifying why the prevalence of temporomandibular disorders is greater in women than in men. Keywords: glutamate, jaw-stretch reflex, masticatory muscle, sex differences, trigeminal pain mechanisms

Aims: To determine the temporomandibular joint (TMJ) pressure pain threshold (PPT) in female patients with rheumatoid arthritis (RA) and TMJ involvement in comparison with healthy females, in order to determine its clinical usefulness for local pain assessment. Methods: Forty-two female patients with the diagnosis of RA, 17 of them positive and 25 negative for rheumatoid factor were investigated, as well as 17 healthy females. A pressure algometer was used to assess the PPT over the TMJ and (as a reference) the center of the glabella. The mean of the second and third TMJ PPT was used in the analysis, and the ratio between the TMJ PPT and the PPT of the reference site (PPT ratio) was calculated. Temporomandibular joint resting pain and pain upon maximum voluntary mouth opening was assessed by a visual analog scale on each side. Results: The TMJ PPT (median/10th to 90th percentile) and PPT ratio were significantly lower in the RA patients (148/64 to 220 and 0.63/0.40 to 1.01, respectively) than in the healthy individuals (217/111 to 352 and 0.85/0.51 to 1.25), but the overlap was considerable. Conclusion: This study shows that the PPT of the TMJ in RA patients is lower than in healthy individuals and that it can be used for pain assessment. However, the clinical use of the TMJ PPT and PPT ratio measurements alone is limited from a diagnostic point of view. Keywords: pain, pain threshold, pressure, rheumatoid arthritis, temporomandibular joint

Aim: To examine, in a double-blind and placebo-controlled crossover manner, the effect of topical application of capsaicin on the alveolar mucosa with a battery of intraoral quantitative sensory testings (QST) in 16 healthy volunteers. Methods: Thirty µL of 5 mg/mL capsaicin or vehicle (control) was applied to a 3 x 3- mm paper disk and applied to the alveolar mucosa under an oral bandage. The subjects rated the perceived pain intensity on a 0 to 10 electronic visual analog scale (VAS) for 15 minutes. Quantitative sensory testings were performed before and immediately after the 15-minute application and consisted of assessments of cold detection threshold, warmth detection threshold (WDT), cold pain threshold, heat pain threshold (HPT), mechanical sensitivity to single and repeated punctate mechanical stimulation with von Frey filaments and to single and repeated brush stimulation with a cotton swab, and detection and pain thresholds to electrical stimulation of the alveolar mucosa and maxillary first premolar tooth. Analysis of variance was used to test the data. Results: Application of capsaicin caused moderate levels of pain (VASpeak scores 5.0 ± 1.9) whereas the vehicle was practically painless (VASpeak 0.9 ± 2.4). No significant effects of vehicle on QST could be detected (P > .143). In contrast, capsaicin application was associated with significant decreases in WDT and HPT (P .001). No other significant changes in QST were observed for capsaicin application. Conclusion: The intraoral capsaicin pain model is associated with signs of heat hyperalgesia, but not mechanical hyperalgesia. Since the somatosensory sensitivity is not well characterized in most orofacial pain conditions, mainly due to lack of tradition and techniques, intraoral QST may provide a better description of the somatosensory sensitivity and underlying mechanisms in orofacial pain conditions. Keywords: capsaicin, hyperalgesia, orofacial pain, pain measurement

Aims: To evaluate a method for self-registration of maximum mandibular opening capacity by means of a spatula and estimation of vertical overbite from photos. Methods: The study group consisted of 50 adults. Each participant received written instructions, photos, a measuring spatula, and a pencil. The first task was to register maximum interincisal distance. The participant opened up his or her mouth as wide as possible, looked in a mirror, and marked the distance on the spatula. The second task was to estimate the vertical overbite in the intercuspal position. A clinician then estimated the type of overbite and measured the maximum interincisal distance and the vertical overbite with a ruler in millimeters. Results: The normal overbites showed a mean value of 2.4 mm, and a standard value of 2 mm was set. The deep bites showed a mean value of 5.2 mm, and a standard value of 5 mm was set. The standard overbite value, added to the value measured on the spatula, was compared with the clinical values made by the clinician for maximum mandibular opening. The limits of agreement for 95% of the mean difference were -4.2 mm and 4.4 mm. Six people missed the correct diagnosis for the vertical overbite. Conclusion: The self-registration method of measuring maximum mandibular opening capacity seems valid for studying major differences in opening capacity when clinical measurements are not possible to perform. Keywords: craniomandibular disorders, mandibular opening, repeatability for measurements, self-registration, temporomandibular joint, vertical overbite

Aims: To investigate parents' ability to perceive pain experienced by their offspring with Down syndrome (DS). Methods: Data were gathered by the use of the Oral Assessment in Down Syndrome Questionnaire in a cross-sectional survey design in France. A sample of parents of 204 children with DS and 161 of their siblings without DS was accrued. Results: Parental reports of difficulty discerning if their child with DS was in pain did not change with age of the child, remaining at a prevalence of 28% to 32%. Reports of difficulty discerning where that child felt pain diminished with older age from 74% to 27%. The likelihood of parents reporting difficulty discerning if and where their child with DS had pain was greater than for a sibling without DS. However, reports of pain experience for the 2 groups were the same. Moreover, different functional and dysfunctional behavioral variables were found to be predictors of these 2 pain perception variables. Conclusion: Parental perception of pain is less discriminant for children with DS than for their siblings without DS. Keywords: Down syndrome, pain perception