M.K.A. van Selms

Principles for the management of bruxism

The management of bruxism has been the subject of a large number of studies. A PubMed search, using relevant MeSH terms, yielded a total of 177 papers that were published over the past 40 years. Of these papers, 135 were used for the present review. Apparently, research into bruxism management is sensitive to fashion. Interest in studying the role of occlusal interventions and oral splints in the treatment of bruxism remained more or less constant over the years: between 1966 and 2007, approximately 40-60% of the papers dealt with this subject. The percentage of papers that dealt with behavioural approaches, on the other hand, declined from >60% in the first 2 decades (1966-1986) to only slightly >10% in the most recent decade (1997-2007). In the latter period, >40% of the papers studied the role of various medicines in the treatment of bruxism, while in the preceding decade (1987-1996), only approximately 5% of the studies dealt with the pharmacological management of bruxism. Unfortunately, a vast majority of the 135 papers have a too low level of evidence. Only 13% of the studies used a randomized clinical trial design, and even these trials do not yet provide clinicians with strong, evidence-based recommendations for the treatment of bruxism. Hence, there is a vast need for well-designed studies. Clinicians should be aware of this striking paucity of evidence regarding management of bruxism.

Myofascial temporomandibular disorder pain, parafunctions and psychological stress

Associations of evening and morning masticatory muscle pain and nocturnal electromyography (EMG) activity with psycho-behavioural factors and occlusal splint therapy were studied during a 20-week study-protocol. Over a period of almost 2 years, only eight of the 120 eligible patients were willing to enroll the study protocol. Further, four of the eight participants dropped out during the study, and approximately 20-30% of the nocturnal EMG recordings failed. Because of the impractical and unworkable nature of the protocol, the study was prematurely terminated and the results of the four remaining individuals are reported here as single-patient clinical trials. Univariate and multiple regression analyses revealed that in three of the four patients, changes in nocturnal EMG activity were associated with the period of splint therapy. However, no associations were found between the changes in nocturnal EMG activity and the observed changes in muscle pain. In two patients, the changes in muscle pain were associated with the period of splint therapy and with the changes in psychological stress. Within the limitations of single-patient clinical trials, it can be concluded that changes in chronic masticatory muscle pain seem to be more related to changes in psychological stress than to those in parafunctional activities.

Self-Reported bruxism and associated factors in Israeli adolescents

Little is known about the epidemiological characteristics of sleep and awake bruxism (SB and AB) in adolescents. The aims of the study were: to assess the prevalence rates of self-reported SB and AB in Israeli adolescents; to determine the associations between SB/AB and several demographical, exogenous and psychosocial factors in Israeli adolescents; and to investigate the possible concordance between SB and AB. The study made use of a questionnaire. The study population included 1000 students from different high schools in the centre of Israel. Prevalence of self-reported SB and AB in the Israeli adolescents studied was 9·2% and 19·2%, respectively. No gender difference was found regarding the prevalence of SB and AB. Multiple variable regression analysis revealed that the following predicting variables were related to SB: temporomandibular joint sounds (P = 0·002) and feeling stressed (P = 0·001). The following predicting variables were related to AB: age (P = 0·018), temporomandibular joint sounds (P = 0·002), oro-facial pain (P = 0·006), and feeling stressed (P = 0·002) or sad (P = 0·006). A significant association was found between SB and AB; that is, an individual reporting SB had a higher probability of reporting AB compared with an individual who did not report SB (odds ratio = 5·099). Chewing gum was the most common parafunction reported by adolescents. The results of this study demonstrate that self-reports of AB and SB are common in the Israeli adolescents population studied and are not related to gender. The significant correlation found between SB and AB may be a confounding bias that affects proper diagnosis of bruxism through self-reported questionnaires only.