Table 1 Characteristics of the subjects
Variables | Classification | Na | %b |
|---|---|---|---|
Sex | Female | 788 | 46.6 |
Male | 900 | 53.4 | |
Total | 1688 | 100.0 | |
Age (years) | 10 | 531 | 31.1 |
11 | 583 | 33.4 | |
12 | 574 | 35.4 | |
Total | 1688 | 100.0 | |
Household income | Low | 375 | 24.9 |
Middle | 882 | 53.1 | |
High | 414 | 22.0 | |
Total | 1671 | 100.0 | |
Frequency of tooth brushing (per day) | ≤ 1 | 211 | 12.8 |
2 | 969 | 58.1 | |
3 | 426 | 25.3 | |
≥ 4 | 73 | 3.8 | |
Total | 1679 | 100.0 | |
Vitamin Dc (two classification) | < 50 nmol | 1038 | 61.7 |
≥ 50 nmol | 650 | 38.3 | |
Total | 1688 | 100.0 | |
Vitamin Dc (four classification) | < 25 nmol | 66 | 4.4 |
≤ 25 to < 50 nmol | 972 | 57.3 | |
≤ 50 to < 75 nmol | 588 | 35.0 | |
≥ 75 nmol | 62 | 3.3 | |
Total | 1688 | 100.0 | |
Caries experience in permanent dentition | No | 827 | 48.3 |
Yes | 861 | 51.7 | |
Total | 1688 | 100.0 | |
Permanent first molar caries experience | No | 867 | 50.8 |
Yes | 821 | 49.2 | |
Total | 1688 | 100.0 |