Table 3 Bivariate analysis and Poisson regression (adjusted for cluster sampling) against caries experience (DMFT > 0) with prevalence ratio (IRR) and 95% confidence interval (CI) (n = 1109)

School sector

   Public

1

   Private

1.3 (1.00–1.64)*

1.1 (0.86–1.42)

Socioeconomic status

   Low

1

   Middle

1.4 (1.14–1.69)*

1.23 (1.02–1.47) *

Gender

   Boy

1

   Girl

1.0 (0.83 – 1.30)

1.1 (0.86–1.30)

Locality

   Urban

   Remote

1.1 (0.8–1.4)

0.90 (0.71–1.10)

Father education

   Low

1

   High

1.4 (1.01–1.82)*

1.13 (0.80–1.6)

Clinical parameters

Mean GI index

   Score ≤ 1

1

   Score > 1

1.03 (0.81–1.30)

0.99 (0.76–1.28)

Mean PI index

   Score ≤ 1

1

   Score > 1

1.00 (0.77–1.26)

1.04 (0.79–1.40)

Flourosis

   Dean's Index score

1

   > 1

1.0 (0.75–1.47)

0.98 (0.66–1.45)

Oral hygiene habits

Tooth-brushing frequency

   Irregular

1

   Daily

1.0 (0.92–1.16)

1.04 (0.93–1.16)

Dentist visit

   No

1

   Yes

0.6 (0.54–0.75)*

0.69 (0.58–0.82)