Table 2 Characteristics of dental study group participants by caries status. Data are presented as mean with 95% CI for continuous measures and proportion (%) for categorical measures. Differences between groups were tested with Students t-test and Chi-square test, respectively

 Age years, mean (95% CI)

6.4 (6.2, 6.6)

6.3 (6.0, 6.5)

0.259

 Boys, %

52.1

32.4

0.070

 Region, south; north, %

52.1; 47.9

35.1; 64.9

0.119

 Fair; darker skin, %

79.2; 20.8

54.1; 45.9

0.014

 Mother education, % ≥12 years

56.3

51.4

0.653

 Father education, % ≥12 years

68.1

51.4

0.126

 BMI, z-score

0.23 (−0.06, 0.52)

0.29 (−0.03, 0.62)

0.764

 Vitamin D supplement, % with reported intake

31.3

38.9

0.466

 Insufficient vitamin D status, %

20.8

37.8

0.084

 S-25(OH) D, nmol/L

62.6 (57.3, 67.8)

57.4 (51.3, 63.5)

0.195

 S-Calcium, mmol/L

2.43 (2.41, 2.45)

2.45 (2.43, 2.47)

0.339

 S-Phosphate, mmol/L

1.57 (1.53, 1.61)

1.51 (1.46, 1.55)

0.033

 S-Magnesium, mmol/L

0.88 (0.86, 0.89)

0.85 (0.84, 0.87)

0.015

 Parathyroid hormone (PTH), pmol/L

3.86 (3.47, 4.30)

3.68 (3.32, 4.04)

0.512

 Osteocalcin, μg/L

86.2 (79.1, 93.4)

81.3 (73.1, 89.6)

0.364

Alkaline phosphatase, μkat/L

3.94 (3.71, 4.16)

3.99 (3.62, 4.35)

0.812

 Age, years

8.3 (8.1, 8.5)

8.1 (7.8, 8.3)

0.258

 total number

23.5 (23.2, 23.7)

22.9 (22.4, 23.5)

0.059

 deciduous teeth

11.5 (10.7, 12.3)

11.5 (10.6, 12.5)

0.968

 permanent teeth

12.0 (11.2, 12.7)

11.4 (10.5, 12.4)

0.368

 Caries status score (dfs/DFS)

0

4.5 (3.3, 5.8)

<0.001

 single tooth, %

62.5

63.9

0.896

 multiple teeth, %

45.8

44.4

0.899

 Tooth brushing twice a day, %

88.9

94.3

0.397

 LL37, ng/mL

1.01 (0.74, 1.29)

1.56 (1.24, 1.88)

0.012

 S. mutans, % positive by PCR

27.1

33.3

0.535

 S. sobrinus % positive by PCR

0

0

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