Table 3.
Subclasses of temporomandibular disorders. Differences between patients diagnosed with myalgia (n = 10) and patients diagnosed with myofascial pain with or without referral (n = 10) according to the Diagnostic criteria for temporomandibular disorders. Orthogonal projections to latent structure model characteristics: R2 = 0.7, Q2 = 0.4, CV-ANOVA = 0.01. Variables with VIP above 1.0 in the orthogonal partial least-squares discriminant analysis model are shown in decreasing order of VIP values. The p-value is according to the Mann–Whitney data analysis.
| Variable | Myalgia | Myofascial Pain | VIP | p-Value |
|---|---|---|---|---|
| Phosphoglycerate kinase 1 | 1 282 ± 519 | 323 ± 441 | 2.090 | 0.001 |
| PPT masseter muscle (kPa) | 227 ± 59 | 141 ± 31 | 1.945 | 0.001 |
| Level of physical activity * | ≥ 3 times/week | 1–2 times/week | 1.639 | 0.039 |
| PHQ-9 SCORE (0–36) | 4 (6) | 8 (8) | 1.571 | 0.121 |
| Alpha-amylase 1; Alpha-amylase 2B | 2 927 ± 1 885 | 1 102 ± 1 624 | 1.569 | 0.017 |
| Current pain intensity (NRS) | 4 (3) | 6 (1) | 1.511 | 0.023 |
| CPI | 53 (20) | 73 (17) | 1.474 | 0.023 |
| GCPS (Grade 0–IV) | 2 (2) | 3 (1) | 1.431 | 0.131 |
| Alpha-amylase 1; Alpha-amylase 2B | 1 785 ± 1 498 | 845 ± 827 | 1.389 | 0.140 |
| Chitinase-3-like protein 2 | 1 679 ± 1 177 | 675 ± 636 | 1.265 | 0.026 |
| Glyceraldehyde-3-phosphate dehydrogenase | 5 862 ± 4 225 | 2 568 ± 4 822 | 1.260 | 0.011 |
| PHQ-15 Score (0–30) | 8 (11) | 12 (5) | 1.210 | 0.273 |
| PPT reference (kPa) | 419 ± 151 | 353 ± 103 | 1.210 | 0.450 |
| ISI Score | 9 (13) | 12 (14) | 1.188 | 0.488 |
| Headache duration (years) | 3 ± 4 | 8 ± 4 | 1.120 | 0.037 |
| PSS Score (0–40) | 13 (11) | 19 (7) | 1.073 | 0.121 |
PPT = Pressure Pain Threshold; GCPS = Graded Chronic Pain Scale; * Median level of physical activity/week.