Table 1.
Characteristics of the adolescents by outcome variables (n = 1517).
| Variables | N (%) | Daily Intake of Free Sugars |
Dental Caries (DMFT ≥ 1) | DMFT |
|---|---|---|---|---|
| (g/d, Mean ± S.D.) | n (%) | Weighted Mean (95% CI) | ||
| Total samples | 1517 (100) | 53.1 ± 44.8 | 863 (56.9) | 1.45 (1.36, 1.54) |
| Sex | ||||
| Boy | 808 (53.3) | 54.5 ± 44.1 | 421 (52.1) *** | 1.25 (1.14, 1.36) *** |
| Girl | 709 (46.7) | 51.6 ± 42.8 | 442 (62.3) | 1.68 (1.55, 1.81) |
| Age (y) | ||||
| 12 | 396 (26.1) | 48.3 ± 43.1 * | 228 (57.6) | 1.54 (1.35, 1.72) |
| 13 | 717 (47.3) | 54.4 ± 45.4 | 408 (56.9) | 1.44 (1.31, 1.56) |
| 14 | 404 (26.6) | 55.8 ± 45.0 | 227 (56.2) | 1.39 (1.23, 1.55) |
| Grade | ||||
| 7th grade | 784 (51.7) | 50.2 ± 44.2 ** | 449 (57.3) | 1.49 (1.36, 1.61) |
| 8th grade | 733 (48.3) | 56.3 ± 45.1 | 414 (56.5) | 1.41 (1.29, 1.53) |
| Only child | ||||
| Yes | 678 (44.7) | 52.9 ± 44.9 | 364 (53.7) * | 1.34 (1.21, 1.46) * |
| No | 839 (55.3) | 53.4 ± 44.7 | 499 (59.5) | 1.54 (1.42, 1.66) |
| BMI status | ||||
| Normal | 1103 (72.7) | 54.6 ± 45.8 | 650 (58.9) ** | 1.55 (1.44, 1.65) *** |
| Overweight/obese | 414 (27.3) | 49.2 ± 41.7 | 213 (51.4) | 1.20 (1.04, 1.35) |
| Ethnicity | ||||
| Han | 1448 (95.5) | 53.3 ± 44.8 | 828 (57.2) | 1.46 (1.37, 1.55) |
| Minorities | 69 (4.5) | 50.3 ± 44.7 | 35 (50.7) | 1.29 (0.87, 1.71) |
| Domiciled place | ||||
| City | 1014 (66.8) | 53.6 ± 45.3 | 559 (55.1) * | 1.40 (1.29, 1.50) |
| Countryside | 503 (33.2) | 52.2 ± 43.7 | 304 (60.4) | 1.56 (1.41, 1.72) |
| Live in or out | ||||
| Dormitory | 118 (7.8) | 62.4 ± 50.1 * | 77 (65.3) | 1.53 (1.25, 1.82) |
| Own home | 1399 (92.2) | 52.4 ± 44.2 | 786 (56.2) | 1.44 (1.35, 1.54) |
| Family monthly income | ||||
| Low | 408 (39.8) | 51.2 ± 44.6 | 236 (57.8) | 1.45 (1.28, 1.62) |
| Middle | 370 (36.0) | 53.9 ± 43.0 | 219 (59.2) | 1.51 (1.34, 1.69) |
| High | 248 (24.2) | 54.9 ± 45.9 | 131 (52.8) | 1.40 (1.18, 1.63) |
| Parents’ education attainment | ||||
| Primary school or blow | 66 (5.1) | 52.5 ± 46.3 | 39 (59.1) | 1.30 (0.92, 1.68) |
| Middle school | 380 (29.7) | 55.9 ± 47.3 | 211 (55.5) | 1.44 (1.27, 1.61) |
| High school | 459 (35.8) | 51.8 ± 42.5 | 256 (55.8) | 1.39 (1.24, 1.55) |
| University or above | 376 (29.4) | 51.0 ± 42.8 | 215 (57.2) | 1.51 (1.33, 1.69) |
| Dental health education in school | ||||
| Yes | 1024 (67.5) | 52.2 ± 43.4 | 598 (58.4) | 1.51 (1.41, 1.62) * |
| No | 493 (32.5) | 55.1 ± 47.3 | 265 (53.8) | 1.32 (1.17, 1.47) |
| Teeth brush frequency | ||||
| ≤ 1 time/day | 587 (38.7) | 54.5 ± 44.8 | 327 (55.7) | 1.37 (1.24, 1.50) |
| ≥ 2 times/day | 930 (61.3) | 52.3 ± 44.7 | 536 (57.6) | 1.50 (1.39, 1.62) |
| Brush teeth after sugars intake | ||||
| Yes | 166 (10.9) | 45.8 ± 44.6 ** | 99 (59.6) | 1.59 (1.30, 1.88) |
| No | 1351 (89.1) | 54.0 ± 44.7 | 764 (56.6) | 1.43 (1.34, 1.53) |
| Use of dental floss or mouthwash | ||||
| Yes (one or both) | 477 (31.4) | 57.0 ± 47.4 * | 277 (58.1) | 1.48 (1.33, 1.64) |
| No (neither) | 1040 (68.6) | 51.4 ± 43.4 | 586 (56.3) | 1.44 (1.33, 1.54) |
| Regular dental visiting | ||||
| Yes | 318 (21.0) | 53.2 ± 47.7 | 202 (63.5) ** | 1.67 (1.47, 1.88) ** |
| No | 1199 (79.0) | 53.1 ± 44.0 | 661 (55.1) | 1.39 (1.30, 1.49) |
* p < 0.05, ** p < 0.01, *** p < 0.001; compared by Mann–Whitney U test, Kruskal–Wallis test or Chi-square test. DMFT: decayed, missing, and filled permanent teeth. BMI status: grouped by age- and sex- specific BMI cut-off values. Family monthly income: low (<5000 RMB), middle (5000–9000 RMB), high (>9000 RMB). RMB: Renminbi, Chinese official coupons, 1 RMB ≈0.16 USD.