Diagnosis and treatment of temporomandibular disorders: an ethical analysis of current practices.

The defining characteristic of a profession - and especially a health-care profession - is that the behaviour of its members is proscribed by a formal code of ethics. The main purpose of such codes is to guide practitioners' interactions with patients, assuring that patient interests are protected. In other words, the ethical code requires practitioners to place their patients' needs for proper diagnosis and appropriate treatment ahead of their own needs for income and advancement. The dental profession has a code of ethics that was developed by the American Dental Association many years ago; in most clinical situations, determination of proper behaviour is self-evident. However, the field of temporoman-dibular disorders (TMDs) has been the subject of considerable controversy for over half a century, and many people have argued that this makes it impossible to evaluate various approaches to treatment of TMDs within an ethical framework. In this article, the authors argue that the large volume of scientific evidence in the contemporary TMD literature provides an ethical framework for the diagnosis and treatment of patients with TMDs within a biopsychosocial medical model. They present a summary of the research with contemporary scientific integrity, which has produced that information over a period of many years. Based on that research, they conclude that dentists may provide conservative and reversible treatments that will be successful for most TMDs and in doing so will comply with the profession's code of ethics. Conversely, the authors claim that those dentists who continue to follow the older mechanistic models of TMD aetiology and treatment are not only out of step scientifically, but are placing their patients' welfare at risk by providing unnecessary irreversible bite-changing and jaw-repositioning interventions. Therefore, debate of these issues should not be solely focused on scientific merit, but also upon the compelling ethical obligations that dentists have as a result of the contemporary scientific literature regarding TMDs.

Psychosocial profiles of patients with burning mouth syndrome.

AIMS: Burning mouth syndrome (BMS) is estimated to affect 1 to 5% of the adult population, with women experiencing symptoms more frequently than men. The purpose of this study was to examine the psychosocial profiles of BMS patients to determine whether psychologic factors are related to pain reports. Based on previous literature, it was hypothesized that patients with BMS would be characterized by clinical elevations on standardized psychologic assessment instruments that included the Revised Symptom Checklist (SCL-90R) and the Multidimensional Pain Inventory (MPI). METHODS: Thirty-three BMS patients completed the McGill Pain Questionnaire, MPI, and SCL-90R during their initial clinical evaluation session. The SCL-90R and MPI data were then summarized and presented in standardized format (T-scores) to enable meaningful comparisons with larger population samples that included both a chronic pain population and a normal nonclinical sample. RESULTS: The T-score for the overall pain severity on the MPI was 40.8 (SD 12.8). For the entire BMS sample, there was no evidence for significant clinical elevations on any of the SCL-90R subscales, including depression, anxiety, and somatization. Moreover, patients reported significantly fewer disruptions in normal activities as a result of their oral burning pain than did a large sample of chronic pain patients. CONCLUSION: These findings indicate that, as a group, this sample of BMS patients did not report significant psychologic distress. There were, however, individual cases (7 of 33, or 21%) where psychometric data indicated a likelihood of psychologic distress, and further evaluation by a competent health professional would be warranted for those individuals.

Influence of a sympathomimetic amine on masticatory and trapezius pain/pressure thresholds and electromyographic levels.

OBJECTIVES: This study examined the influence of terbutaline, a beta-adrenergic sympathomimetic amine on pain/pressure thresholds in the index fingers and masseter and trapezius muscles and electromyographic activity in trapezii. STUDY DESIGN: In a randomized and double-blind controlled trial, 20 asymptomatic female subjects were assigned to receive either an injection of terbutaline or sterile water before collection of pain/pressure thresholds and electromyographic levels. Repeated analysis of variance and paired t tests were calculated to test for baseline and postinjection differences between groups. RESULTS: No significant baseline or postinjection group differences in pain/pressure thresholds or electromyographic were detected. CONCLUSIONS: beta-adrenergic sympathomimetic stimulation does not influence pain/pressure thresholds or electromyographic activity in the masselet and trapezius muscles or pain/pressure thresholds in the index fingers. These results suggest that development of painful muscle conditions is not caused by elevations of sympathetic activity.

The influence of cutaneous tissue afferents on masticatory pain-pressure thresholds.

Pain-pressure thresholds are routinely used in orofacial pain research to record tenderness in masticatory muscles. This method is employed to stimulate deep tissue afferents, which are thought to be at least partially responsible for pain in temporomandibular disorders. Like other psychophysical measurements, however, this technique must stimulate cutaneous tissues before stimulating deeper tissues. This study examined 39 asymptomatic volunteers to quantify the effect of cutaneous sensory afferents on pain-pressure thresholds. In a randomized, double-blind fashion, pain-pressure thresholds were recorded at four facial sites before and after subjects received intradermal local anesthetic or a dry needle stick. Pain-pressure thresholds were significantly elevated after local anesthetic (P < .0001), suggesting that cutaneous tissues contribute significantly to the pain-pressure threshold. The authors discuss potentially important roles of cutaneous tissues in the assessment of deeper tissues and offer two theories of how the skin may be an important link in the assessment of temporomandibular disorders.

Physical and sexual abuse among orofacial pain patients: linkages with pain and psychologic distress.

This study examines the incidence of and the potential correlates of sexual and physical abuse among facial pain patients. An anonymous survey composed of standardized self-report measures of abuse, pain, and psychologic status was distributed to 120 adult facial pain patients following their initial evaluations. Forty-five questionnaires were returned by mail. In addition, 206 charts were randomly selected from a population of 520 new patients seen at the Orofacial Pain Center during the same time period that data from the anonymous survey were collected. Results of the anonymous survey indicated that 68.9% of the patients reported a history of abuse. Conversely, a chart review revealed that only 8.5% of the patients indicated a history of abuse on the clinic questionnaire. History of abuse was significantly related to greater pain severity, depression, psychologic distress, and various personality characteristics. Overall, this study indicates that the assessment of the history of abuse may be an important factor in the evaluation and treatment of facial pain.

Evaluation of iontophoretically applied dexamethasone for painful pathologic temporomandibular joints.

The effects of iontophoretically applied dexamethasone in a lidocaine vehicle were compared with those of saline placebo in 53 patients with one of three diagnoses of painful temporomandibular joint pathologic conditions: disk displacement with reduction, disk displacement without reduction, and osteoarthritis. Both dexamethasone and the saline placebo produced a significant reduction in pain scores from baseline levels after the first two of three treatments. There were no observed differences, however, in pain report or mandibular range of motion between the dexamethasone and placebo groups. A trend for pain relief was noted in the subgroup that received dexamethasone with a diagnosis of osteoarthritis. Results may reflect varying degrees of inflammation or central nervous system hyperexcitability, or both, in this heterogeneous study sample. Potential confounding variables were lack of knowledge of actual drug penetration, the effects of electric current transmitted by the iontophoresor, and pain reduction caused by cyclic fluctuations in symptoms. These data suggest that iontophoretically applied dexamethasone is no more effective than saline placebo in providing pain relief in patients with temporomandibular joint pain.

The influence of time, facial side, and location on pain-pressure thresholds in chronic myogenous temporomandibular disorder.

This study examined masseter and temporalis pain-pressure thresholds in 29 patients with chronic bilateral myogenous temporomandibular disorder and in 11 controls. Patients with evidence of temporomandibular joint pathosis were omitted. The influence of time, facial side, muscle site, and side of greatest spontaneous pain on pain-pressure thresholds was measured. No significant pain-pressure threshold differences were found between the more and less painful sides, as indicated by the patients, which lends support to theories of centrally mediated pain. Mean pain-pressure thresholds in patients differed over the four sessions, which is consistent with recent reports of fluctuating levels of pain in patients with temporomandibular disorders. Additional findings included significant pain-pressure threshold differences among muscle sites in patients and controls, and lower patient pain-pressure thresholds relative to controls. Within- and between-session reliability was adequate for patients (r = .85 and r = .75, respectively) and controls (r = .90 and r = .75, respectively).