A number of unanswered questions and problems surround the clinical application of massed practice therapy for bruxism. The clinical effectiveness of the treatment remains unverified. When patient reports are employed to evaluate treatment outcome (Ayer, 1976; Ayer and Gale, 1969; Ayer and Levin, 1973; Wolpe, 1958), massed practice appears effective in up to 75% of the cases and is maintained for a year. However, when attempts to measure nocturnal bruxism are reported (Heller and Forgione, 1975; Rugh, 1975; Rugh and Solberg, 1974), treatment effects appear weak or nonexistent. A major problem in the investigations of bruxism is the lack of an agreed upon operational definition. Bruxism has been quantified through a variety of methods including self-reports, tooth wear, audio tape recordings, wear patterns on nightguards, wear on thin occlusal indicators, and electromyography. The advantages and limitations of these measurement. procedures have been discussed by Klepac (1977) and Rugh (1978). These authors note that some measurement methods are differently sensitive to clenching and grinding. Reports of a sleeping partner, tooth wear, audio tape recordings and occlusal wear indicators may be suitable methods to detect grinding; however, it is unlikely that these methods reflect sustained teeth clenching which may prove equally damaging. Electromyographic measurements are sensitive to both clenching and grinding, but require more equipment and expense, and may disrupt the behavior under study. Ti importance of the method of assessing bruxism may be seen in the large differences reported in studies of the incidence of bruxism in the general population. Kraft (1959), using verbal self-reports, found that only 13% of his population ground their teeth. Leof (1944) and Frolich (1966), on the other hand, reported figures of 78% and 56%, respectively, when evaluations of tooth wear were made. Studies need to be directed at the comparability, reliability, and reactivity of the various measures of bruxism. The potentials and limitations of each measure need to be clearly specified. A review of the massed practice studies thus far indicates little agreement on the mechanism involved in the treatment effectiveness. Although reactive inhibition (fatigue) has been proposed (Ayer and Levin, 1975; Yates, 1958), few of the massed practice treatment programs are of sufficient length or intensity to involve reactive inhibition. Reactive inhibition has historically been indicated by observing a reduction in response frequency or magnitude during the practice period. None of the reports thus far have tested for such changes. Rugh (1975) has discussed alternative explanations including contingent punishment, stress reduction, homeostasis, and response sensitization as possible mechanisms responsible for the treatment effectiveness. An understanding of the mechanism responsible for treatment effectiveness would allow better specification of optimum therapeutic procedures. The literature on massed practice suffers many of the same problems of earlier reports. Authors seldom define their subject population or the precise nature of the habit being treated. Were the subjects introductory psychology students or patients seeking treatment at a clinic? Did the subjects report symptoms related to the bruxism habit and was the bruxism nocturnal or diurnal? Treatment effectiveness is often altered by the manner in which the treatment is presented to the patient. Authors should describe how the treatments were presented, i.e., enthusiastically, casually, or as an experimental test. In light of the positive reports in several papers describing massed practice treatment for bruxism, it would seen useful to continue exploratory efforts along this line. Future studies, however, must involve objective measures of bruxism, better patient descriptions, and comparison control groups. The problem of patient compliance to the required clenching exercise discussed by Ayer and Levin (1973) also deserves study; however, not until the treatment efficacy has been established. As suggested by Klepac (1977), future studies should take care that the practiced response is very similar to the problematic habit (bruxism). Yates (1970) believed that the practice behavior should closely replicate or mimic the unwanted habit. Klepac (1977) also noted that massed practice treatments of bruxism have thus far involved minimal fatigue during practice sessions. Yates (1970), Bandura (1969), and Wolpe (1958) have all pointed to the importance of prolonged practice sessions to ensure fatigue and exhaustion. Based upon these recommendations, future studies evaluating clinical efficacy might investigate increasing the duration or magnitude of the practice periods. Myofascial Pain Dysfunction/Temporomandibular Joint Dysfunction Several studies using behavioral therapy for the management of MPD or TMJ are available. In general, the reports have attacked the problem from a behavioral standpoint in that the presupposed etiology is masticatory muscle hyperactivity resulting from the inability or loss of the ability to control muscle contraction or from bruxism. Yemm (this volume) has reviewed the evidence for this etiological position. Obviously, practitioners in any field treat or manage a disease or dysfunction based on their ideas or the etiology involved. It could be said that most of the reports to be considered view the etiology of MPD or TMJ dysfunction to be bruxism or some other form of habit leading to masticatory muscle hyperactivity or "spasm." Thus the treatment or management is aimed at changing the patient's behavior from one involving muscle hyperactivity to a more relaxed state or changing a suspected bruxist activity. MPD is a disorder defined by a rather broad set of symptoms, several of which may be caused by many different diseases (Ramfjord and Ashe, 1971). The possible symptoms include pain of a dull variety in the ear or preauricular area, masticatory muscle tenderness, clicking or popping in the temporomandibular joint, and limitation of jaw function. Also included are two negative symptoms: absence of organic changes in the TMJ and lack of tenderness in the TMJ (Laskin, 1969). It is implied that the two negative symptoms separate this dysfunctional problem from what is commonly called TMJ dysfunction or from the several arthritic conditions (Kapp, 1977b) which can also present the same positive symptoms plus the two negative symptoms. Several review papers are available which attempt to explain the differences in etiology and pathogenesis between TMJ dysfunction and MPD (DeBoever, 1973; Klineberg, 1978; Speck and Zarb, 1976). However, the definitional differences or the reported etiological differences have not solved the problems encountered by clinicians in patients management or by investigators studying pain or dysfunction of the masticatory system. Biofeedback. Several methods of utilizing biofeedback have been used in the management of MPD and TMJ dysfunction. Both nocturnal feedback and diurnal biofeedback relaxation therapy have been reported. Daytime biofeedback has been used by several authors based on the work of Yemm (1969, 1976), indicating that muscle tension is a problem in these patients when compared with normal patients or those not presenting with the symptoms of MPD or TMJ dysfunction. Another early paper (Budzynski and Stoyva, 1963) showed that with biofeedback, healthy subjects could learn to reduce masseteric muscle activity. Carlsson and Gale (1977) studied the effects of 6 to 18 biofeedback sessions extending over a 1 to 3-month period. The 11 subjects were selected from patients who were refractory to other methods of treatment and who had at least a 3-year history of dysfunction problems. The authors presented a table describing the patients' symptoms, previous treatments, and EMG data, as well as a scale of results. The 7-point scale of results is an attempt to categorize the symptoms at the end of therapy ranging from "significantly worse" through "no change" to "totally symptom-free." Results indicated 9 of the 11 patients were at least "significantly better" after the biofeedback sessions. Carlsson and Gale (1977) attempted to do several things which should be done in all reports of clinical research. First, the subjects and the symptoms were described. The method and length of treatment sessions were detailed. Another important feature of this presentation is the scale describing the outcome of the treatment. Until better diagnostic categories and better quantification of symptoms and/or symptom relief are available, the presentation employed in this paper is recommended. Other reports of the daytime use of biofeedback include Berry and Wilmot (1976), Dohrmann and Laskin (1976), and Gessel (1975). A common feature of these three articles is the categorization of patients as being either improved or not improved with no elaboration of the criteria involved. Even though all report that a high percentage of their patients were reported as improved, it is very difficult to compare results among these papers or with other studies such as the CarlssonGale study. The use of nocturnal biofeedback in the management of MPD is reported by Clarke and Kardachi (1977). This paper presents a series of anecdotal case presentations of seven patients. The conclusion of this paper (that the etiology of MPD is stress-induced parafunction), while certainly not illogical, is not warranted by any data presented. Recommendations In a publication entitled "Self-Injurious Behavior A Review and Analysis of Methodological Details of Published Studies, Baumeister (1978) analyzed 60 published studies for what they consider "important inclusions in research and reports in this area." The authors critized the publications according to how 10 criteria were met in reporting the studies. A critique and summary follows: 1. Method of treatment: Unless comparing two or more treatment methods, the same method should be applied to the patients in an individual study. In many of the studies reviewed, the treatments are often a combination of contingencies and operations. 2. Number of subjects: Unless the study is specifically designed as a single-subject design, numbers of subjects large enough to have data amenable to proper statistical analysis are recommended. Nonparametric statistics should be used for nonparametric data. 3. Detail of subject description: Detailed descriptions of subjects and of their behaviors to be studied should be adequately presented. 4. Design characteristics: This would include descriptions of baseline procedures (multiple if possible), practicability in clinic settings, and other factors such as the involvement of other personnel who may have influenced the important therapist-patient relationship as well as details of data collection procedures. 5. Reliability of data: Interobserver reliability should be reported. Especially recommended is one observer independent of the study and without the regular observer's awareness. 6. Methods of data collection: Should be reported in detail. 7. 8. Generalization of effects: Are the effects of training generalized across settings and therapists? 9. Followup: The duration of positive effects of treatment is "obviously a highly relevant consideration." Long post-treatment |