Effect of a nociceptive trigeminal inhibitory splint on electromyographic activity in jaw closing muscles during sleep

Abstract

The nociceptive trigeminal inhibitory (NTI) splint has been claimed to decrease the electromyographic (EMG) activity of jaw-closing muscles and relieve symptoms of various types of temporomandibular disorders (TMD) and bruxism. The present study was designed to address the question about EMG-changes during sleep. Ten patients (age: 23-39 years) with a self-report of tooth-grinding during sleep were recruited. Patients were examined at baseline and after each treatment period with the use of the Research Diagnostic Criteria for TMD. A portable EMG-device was used to record EMG-activity from the masseter muscle during sleep. The patients received two 2-week splint treatments in a randomized cross-over fashion; an NTI splint and a standard flat occlusal splint (OS). EMG data were analysed according to published criteria. Using a 10% of maximum clenching EMG-activity cut-off threshold to determine the number of EMG-events h(-1) of sleep, the NTI splint was associated with a significant reduction (9.2 +/- 3.2 events h(-1)) compared with baseline EMG (19.3 +/- 4.0; anova: P = 0.004, Tukey post hoc: P = 0.006), whereas there were no differences between the OS (16.2 +/- 4.7) and baseline EMG (19.2 +/- 4.1; P = 0.716). There were no effects of either NTI or OS on clinical outcome measures (anovas: P > 0.194). This short-term study indicated a strong inhibitory effect on EMG-activity in jaw closing muscles during sleep of the NTI, but not the OS. However, the EMG-activity was not directly related to clinical outcome. Further studies will be needed to determine long-term effects and possible side effects of the NTI splint.

Occlusal splint for sleep bruxism: an electromyographic associated to Helkimo Index evaluation

“…Baad-Hansen et al [30] found a significant reduction in EMG activity in the masseter during sleep when patients used nociceptive trigeminal inhibitory (NTI) splint and, curiously, found no significant reduction in EMG activity in the masseter during sleep when patients used a standard occlusal splint, which converge to our findings using the same type of device. Conversely, the reduction in masseter EMG using NTI was not associated with a reduction in signs or symptoms of the patients.…”

Behavior analysis of electromyographic activity of the masseter muscle in sleep bruxers

“…Each patient received both splints and the study lasted 7e8 weeks including the washout period. The authors concluded that the significant decrease of EMG activity is not associated with a reduction in temporomandibular disorders' signs or symptoms, once 5 of 10 patients perceived pain at baseline (Baad-Hansen et al, 2007).…”

To see bruxism: a functional MRI study

“…8 The influence of cerebral circuits on occlusal movements is unknown, and it has been suggested that possible benefits of an occlusal splint arise from the presence of a foreign object, consciousness or cerebral learning. 9,10 MRI is a sophisticated technique that presents structural anatomy of the brain with high spatial resolution. Functional MRI (fMRI) provides anatomical data in addition with functional data.…”