Effect of contingent vibratory stimulus via an oral appliance on sleep bruxism after the splint adaptation period

Abstract

Background Contingent vibratory feedback stimuli applied by a specially designed oral appliance (OA) have been reported to be effective in reducing sleep bruxism (SB). However, the inhibitory effects of the OA, which occur immediately after OA delivery, may have confounded this finding. Objective This study sought to shed light on the effects of vibratory stimuli on SB after the OA adaptation period, when its inhibitory effects are diminished. Methods Fourteen ‘definite’ SB patients were enrolled. A force‐based bruxism detection system was utilised to trigger a vibrator attached to the OA. Masseter electromyographic activity during sleep was recorded at home using portable polysomnography. After using the OA without vibratory stimulus for 16 nights (adaptation period), intermittent vibratory stimuli were applied every other half‐hour for four nights (intervention period). Electromyographic activity over 10% of the maximum voluntary contraction was regarded as a SB episode. The number and the total duration of SB episodes per hour of sleep were calculated for the sessions with and without stimuli separately and averaged for four intervention nights. The effects of stimuli on these two variables were evaluated. Results The number and the total duration of the sessions without stimuli were 5.2 episodes/h and 35.3 s/h, respectively. These values significantly decreased to 3.9 episodes/h and 15.1 s/h (p < .05) for the sessions with vibratory stimuli. Conclusion Contingent vibratory stimulus via an OA may be effective for the management of SB even after adaptation to OA.

Effects of vibratory feedback stimuli through an oral appliance on sleep bruxism: a 6-week intervention trial

“…Our subsequent study, which allowed a 2-week period for adapting to the OA, demonstrated significant inhibition of the two SB variables immediately after the OA delivery, and such inhibitory effects diminished after the adaptation period [16], similar to the findings of previous studies [13,14]. Another previous study also reported a more significant inhibitory effect on the duration than on the number of SB episodes [16], which is in line with the current study results. This suggests that the vibratory stimulus is more effective in reducing the duration of SB episodes than the number of SB episodes.…”

“…Since the previous study evaluated the immediate effect of OA-based vibration stimulation, the results may have been confounded by the short-term inhibitory effects of the OA [13,14]. Our subsequent study, which allowed a 2-week period for adapting to the OA, demonstrated significant inhibition of the two SB variables immediately after the OA delivery, and such inhibitory effects diminished after the adaptation period [16], similar to the findings of previous studies [13,14]. Another previous study also reported a more significant inhibitory effect on the duration than on the number of SB episodes [16], which is in line with the current study results.…”

“…Based on the authors' previous study [16], vibration stimulation via an OA was expected to decrease the duration of SB episodes by 50%. To detect this change, a sample size of 8 subjects was required, assuming a risk of 5% (α = 0.05) and a power of 90% (β = 0.10).…”

“…In a subsequent clinical trial, the authors applied vibratory stimuli to 14 patients with "definite" SB for 4 consecutive nights after a 2-week OA adaptation period. That trial showed that the number and duration of SB episodes significantly decreased by 25% and 57%, respectively, without subjective or objective sleep disturbances [16]. The effects of long-term application of vibration stimulation on SB should be further elucidated in the context of clinical applications.…”

Managements of sleep bruxism in adult: A systematic review

“…Finally, 11 articles were selected as review papers, of which seven focused on electric stimulation [48] , [49] , [50] , [51] , [52] , [53] , [54] , and five on vibration [55] , [56] , [57] , [58] , [59] and two on sound [60] , [61] stimulation. In addition, two review articles (one systematic review [62] and one meta-analysis [63] ) were included in the review process.…”