Table 2 Descriptive statistics of the first test series. The values show the percentage of demineralization (= black pixels) in a defined image section of the respective analysis surfaces (S0—S4) after 8 h of demineralization and 2 min of remineralization with the different toothpastes (Karex, Elmex and Ajona)

S0 = control surface

57

0.35 ^a

0.24

0.04/0.84

S1 = only demineralization with lactic acid

57

11.78 ^b

1.26

10.02/13.81

S2 = demineralization with lactic acid + remineralization with Karex

57

9.85 ^c

1.63

7.41/12.71

S3 = demineralization with lactic acid + remineralization with Elmex

57

5.01 ^d

0.98

3.58/6.98

S4 = demineralization with lactic acid + remineralization with Ajona

57

8.89 ^e

1.41

6.20/11.93