Table 1.
Primary sleep bruxism: overview of randomized clinical trials
| Citation | Study type | Group | Intervention | Duration | Results |
|---|---|---|---|---|---|
| Splint therapy | |||||
| Dubé et al. [19] | Crossover RCT | 9 definitive sleep bruxism | Occlusal splint Palatal splint |
2 weeks | Both occlusal splints and palatal splints reduced rhythmic masticatory activity during the PSG. |
| Van der Zaag et al. [20] | Parallel RCT | 21 probable sleep bruxism | Occlusal splint Palatal splint |
4 weeks | Neither occlusal splints nor palatal splints reduced rhythmic masticatory activity during the PSG. |
| Harada et al. [21] | Crossover RCTa | 16 probable sleep bruxism | Occlusal splint Palatal splint |
6 weeks | Both occlusal splints and palatal splints reduced nocturnal masseter activity on portable EMG the night after the insertion of splints, but not after 2, 4, or 6 weeks of therapy. |
| Landry et al. [22] | Crossover RCT | 14 definitive sleep bruxism | Occlusal splint Mandibular advancement device in 3 grades of protusion: • No protrusion • At 40 % • At >75 % |
Irregular | Both occlusal splints and mandibular advancement devices reduced rhythmic masticatory activity during the PSG. Higher advancement with mandibular advancement devices was associated with larger decrease on rhythmic masticatory activity. |
| Landry-Schönbeck et al. [23] | Crossover RCT | 12 definitive sleep bruxism | Occlusal splint Mandibular advancement device in 2 grades of protusion: • At 25 % • At 75 % |
2 weeks | Mandibular advancement devices reduced rhythmic masticatory activity during the PSG. Occlusal splint tended to reduce rhythmic masticatory activity during the PSG (n.s.) |
| Arima et al. [24] | Crossover RCTa | 11 possible sleep bruxism | Occlusal splint Mandibular advancement device in neutral position, in 2 conditions: • Not fix • Fix |
1 week | Both occlusal splints and mandibular advancement devices reduced nocturnal masseter EMG activity on portable EMG. No differences between devices. |
| Madani et al. [25] | Single-blind, parallel RCT | 20 definitive sleep bruxism | Occlusal splint Gabapentin 300 mg |
8 weeks | Both occlusal splints and gabapentin reduced rhythmic masticatory activity during the PSG. |
| Pharmacological therapies | |||||
| Mohamed et al. [26] | Double-blind, crossover RCTa | 10 probable sleep bruxism | Amitriptyline 25 mg Placebo |
1 night | Amitriptyline did not reduce nocturnal masseteric EMG activity on portable EMG. |
| Lobbezzo et al. [27] | Double-blind, crossover, RCTa | 10 definitive sleep bruxism | Levodopa/benserazide 100/25 mg Placebo |
1 night | Levodopa reduced rhythmic masticatory activity during the PSG in 7 of 10 patients. |
| Lavigne et al. [28] | Double-blind, crossover RCT | 7 definitive sleep bruxism | Bromocriptine 7.5 mg Placebo |
2 weeks | Bromocriptine did not reduce rhythmic masticatory activity during the PSG. |
| Huynh et al. [29] | Crossover RCTa | 25 definitive sleep bruxism | Study 1 (N = 10) Propranolol 120 mg Placebo Study 2 (N = 16) Clonidine 0.3 mg Placebo |
1 night | Propranolol did not reduce rhythmic masticatory activity during the PSG. Clonidine decreased rhythmic masticatory activity during the PSG by > 60 %. |
| Shim et al. [30••] | Randomized, parallel, before-after studya | 20 probable sleep bruxism | Botulinum toxin type A in masseters Botulinum toxin type A in masseters + temporalis |
4 weeks | Botulinum toxin type A did not reduce rhythmic masticatory activity during PSG, but decreased the strength of contraction in the injected muscles. No differences between injecting 2 (masseters) or 4 (masseters + temporalis) muscles. 9/20 patients reported decreased teeth grinding after the therapy. 50 % reported improvement of morning jaw stiffness. |
| Lee et al. [31] | Double-blind, parallel, RCTa | 12 possible sleep bruxism | Botulinum toxin type A Saline |
12 weeks | Botulinum toxin type A did not reduce nocturnal masticatory activity on portable EMG, but decreased the strength of contraction in the injected muscles. Both botulinum toxin and saline injections improved subjective symptoms of sleep bruxism. |
| Contingent electrical stimulation | |||||
| Jadidi et al. [32] | Double-blind, parallel RCTa | 11 probable sleep bruxism with myofascial pain | Contingent electrical stimulation Placebo |
6 weeks | Contingent electrical stimulation reduced by 52 % nocturnal temporalis muscle activity on portable EMG during active therapy. No changes in self-reported muscle pain and tenderness were observed. |
| Conti et al. [33] | Single-blind, parallel RCT | 15 probable sleep bruxism with myofascial pain | Contingent electrical stimulation Placebo |
3 weeks | Contingent electrical stimulation reduced nocturnal temporalis muscle activity on portable EMG during active therapy. No changes were found in the placebo group. Contingent electrical stimulation did not influence perceived pressure pain thresholds or pain intensity. |
The initial diagnosis of sleep bruxism is based on the diagnostic grading system proposed by Lobbezzo et al. [1••]: possible SB, based on questionnaires or the anamnestic part of the clinical history; probable SB, based on questionnaire and clinical examination; and definitive SB, based on questionnaires, clinical examination, and confirmed by PSG or portable EMG or audio-video recording. Duration makes reference to treatment duration
EMG electromyography, PSG polysomnography, RCT randomized clinical trials, n.s. not significant
aRandomization methods not further specified