Table 1.
Correlation between moderate (>2 and ≤4 SB episodes/h) and severe (>4 SB episodes/h) sleep bruxism and a diagnosis in accordance with the RDC/TMD.
| RDC/TMD Diagnosis | Moderate Bruxer (n = 23) | Severe Bruxer (n = 35) | Nonbruxer (n = 52) | p-Value |
|---|---|---|---|---|
| Group I | 0.011 | |||
| No group-I diagnosis | 18 | 30 | 52 | |
| I a | 4 | 5 | 0 | |
| I b | 1 | 0 | 0 | |
| Group II, dichotomous | 0.930 | |||
| Yes | 3 | 5 | 6 | |
| No | 20 | 30 | 46 | |
| Group II, detailed | NA | |||
| No group-II diagnosis, right TMJ | 21 | 31 | 48 | |
| II a, right TMJ | 2 | 4 | 4 | |
| II b, right TMJ | 0 | 0 | 0 | |
| II c, right TMJ | 0 | 0 | 0 | |
| No group-II diagnosis, left TMJ | 21 | 31 | 50 | |
| II a, left TMJ | 2 | 4 | 2 | |
| II b, left TMJ | 0 | 0 | 0 | |
| II c, left TMJ | 0 | 0 | 0 | |
| Group III, dichotomous | 0.789 | |||
| Yes | 1 | 3 | 3 | |
| No | 22 | 32 | 49 | |
| Group III, detailed | NA | |||
| No group-III diagnosis | 22 | 32 | 50 | |
| III a | 1 | 2 | 0 | |
| III b | 0 | 0 | 0 | |
| III c | 0 | 1 | 2 |
Group I: Myofascial pain without (I a) or with (I b) limited mouth opening. Group II: TMJ disc displacements with reduction (II a), without reduction with limited mouth opening (II b), and without reduction without limited mouth opening (II c). Group III: TMJ arthralgia (III a), osteoarthritis (III b), or osteoarthrosis (III c). RDC/TMD = research diagnostic criteria for temporomandibular disorders. SB = sleep bruxism. TMJ = temporomandibular joint. NA = not available. Significant p-values are marked in bold.