Table 2.

Caries prevalence and dmft-values (both according to WHO criteria and including initial caries, IC) in preschool children in Hamburg 1977–2016, related to the families’ socio-economic status (SES).

	1977	1987	1993	2006	2016
Prevalence (WHO criteria)
High SES	45.7	28.7	21.1	19.3	14.7
Middle SES	60.9	51.8	41.5	28.2	26.2
Low SES	64.9	65.8	57.9	36.9	42.6
p (Chi2-test)	<0.001	<0.001	<0.001	<0.001	<0.001
Prevalence (incl. IC)
High SES	82.4	59.4	33.6	39.4	40.9
Middle SES	92.2	77.2	50.5	52.7	42.4
Low SES	96.4	88.2	71.3	63.6	51.9
p (Chi2-test)	<0.001	<0.001	<0.001	<0.001	0.114
dmft (WHO criteria)
High SES	1.6	1.2	0.7	0.6	0.4
Middle SES	2.8	2.7	2.0	1.2	0.8
Low SES	3.3	3.5	3.2	1.8	1.9
p (KW-test)	<0.001	<0.001	<0.001	<0.001	<0.001
dmft (incl. IC)
High SES	4.4	2.8	1.2	1.3	1.4
Middle SES	6.6	5.0	2.5	2.5	1.7
Low SES	7.9	6.3	4.0	3.3	2.7
p (KW-test)	<0.001	<0.001	<0.001	<0.001	<0.011