Table 6 Model3 ZINB model in the full sample incorporating interaction terms between baseline caries status and other variables (n = 919).

Baseline caries status

Caries-free

Caries present

4.08

1.00−16.58

0.049

Parents’ caries status

Caries-free

1.53

1.09–2.14

0.014

<0.001

Caries present

0.63

0.45–0.87

0.005

Saliva-sharing behavior

Caries-free

1.37

0.97–1.93

0.073

0.010

Caries present

0.74

0.53–1.02

0.062

Bottle use at bedtime

Caries-free

1.68

1.12–2.52

0.012

0.052

Caries present

0.92

0.58–1.45

0.715

Post-meal mouth rinsing

Caries-free

1.47

1.03–2.09

0.034

0.003

Caries present

0.70

0.51–0.97

0.032

Additives in daily drinking water

Caries-free

1.95

1.30–2.91

0.001

0.037

Caries present

1.06

0.71–1.59

0.771

Snacks intake

Caries-free

1.10

0.79–1.54

0.570

0.481

Caries present

1.30

0.95–1.78

0.103

Candy consumption

Caries-free

1.00

0.69–1.46

0.998

0.142

Caries present

0.69

0.50–0.95

0.024

Bedtime toothbrushing

Caries-free

1.75

1.25–2.45

0.001

0.031

Caries present

1.05

0.76–1.44

0.784

Toothpaste use

Caries-free

0.87

0.61–1.24

0.429

0.898

Caries present

0.90

0.62–1.29

0.555

Dental floss use

Caries-free

1.11

0.60–2.04

0.740

0.303

Caries present

2.17

0.70–6.70

0.177

History of dental attendance

Caries-free

1.21

0.81–1.81

0.354

0.318

Caries present

0.92

0.65–1.30

0.651

zero-inflated

Variables (High risk vs reference)

Odds ratio (OR)

95%CI

P

P for interaction

Baseline caries status

Caries-free

Caries present

3.83

0.48–30.42

0.203

Parents’ caries status

Caries-free

0.96

0.60–1.56

0.884

0.456

Caries present

0.70

0.35–1.39

0.310

Saliva-sharing behavior

Caries-free

1.12

0.69–1.81

0.659

0.777

Caries present

1.26

0.61–2.61

0.527

Bottle use at bedtime

Caries-free

0.53

0.25–1.11

0.094

0.687

Caries present

0.39

0.11–1.43

0.155

Post-meal mouth rinsing

Caries-free

0.88

0.54–1.41

0.589

0.350

Caries present

0.59

0.29–1.17

0.132

Additives in daily drinking water

Caries-free

1.19

0.66–2.17

0.565

0.639

Caries present

0.90

0.34–2.42

0.842

Snacks intake

Caries-free

0.55

0.34–0.89

0.015

0.850

Caries present

0.60

0.29–1.22

0.158

Candy consumption

Caries-free

0.52

0.27–1.01

0.053

0.151

Caries present

0.22

0.08–0.60

0.003

Bedtime toothbrushing

Caries-free

0.86

0.51–1.46

0.579

0.083

Caries present

0.35

0.15–0.83

0.016

Toothpaste use

Caries-free

0.79

0.46–1.35

0.389

0.990

Caries present

0.78

0.32–1.91

0.594

Dental floss use

Caries-free

1.72

0.64–4.61

0.278

0.221

Caries present

0.54

0.11–2.60

0.445

History of dental attendance

Caries-free

1.73

1.00–2.99

0.050

0.025

Caries present

0.58

0.26–1.27

0.173