Table 1 Clinical characteristics according to COVID-19 period

Age^§

33.0 (27.0, 47.0)

32.0 (26.0, 45.0)

33.0 (26.0, 46.0)

0.155

Sex^‡

Male

130 (28.6%)

102 (30.2%)

232 (29.3%)

0.623

Female

325 (71.4%)

236 (69.8%)

561 (70.7%)

Initial NRS^§

4.0 (3.0, 6.0)

4.0 (2.0, 6.0)

4.0 (3.0, 6.0)

0.325

CMO (mm)^†

39.3 (11.0)

39.0 (11.3)

39.2 (11.1)

0.719

MMO (mm)^†

43.7 (9.5)

43.1 (9.7)

43.4 (9.6)

0.410

MOL (MMO ≤ 40)^‡

125 (27.5%)

103 (30.5%)

228 (28.8%)

0.356

Pain on mouth opening^‡

223 (49.0%)

183 (54.1%)

406 (51.2%)

0.153

Palpation^‡

Masticatory muscles

255 (56.0%)

217 (64.2%)

472 (59.5%)

0.021^*

Neck muscles

141 (31.0%)

69 (20.4%)

210 (26.5%)

0.001^*

TMJ

167 (36.7%)

79 (23.4%)

246 (31.0%)

< 0.001^*

Sound^‡

Click

103 (22.6%)

167 (49.4%)

270 (34.0%)

< 0.001^*

Crepitus

38 (8.4%)

62 (18.3%)

100 (12.6%)

< 0.001^*

Joint locking^‡

118 (25.9%)

13 (3.8%)

131 (16.5%)

< 0.001^*

Tooth attrition^‡

166 (36.5%)

77 (22.8%)

243 (30.6%)

< 0.001^*

Tongue ridging^‡

242 (53.2%)

164 (48.5%)

406 (51.2%)

0.194

Mucosal ridging^‡

305 (67.0%)

193 (57.1%)

498 (62.8%)

0.004^*

Contributing factors^‡

Bruxism

106 (23.3%)

100 (29.6%)

206 (26.0%)

0.046^*

Clenching

205 (45.1%)

185 (54.7%)

390 (49.2%)

0.007^*

Perioral contraction

63 (13.8%)

46 (13.6%)

109 (13.7%)

0.924

Tongue thrusting

27 (5.9%)

24 (7.1%)

51 (6.4%)

0.508

Insomnia

135 (29.7%)

89 (26.3%)

224 (28.2%)

0.302