Document Classification

Section Type: RESULTS

Text: The means (standard deviation) of reductions in Knoop hardness values for systems associated with the fluoride-containing dentifrice were : Ke : 40. 0 (1. 02) (a), Fj : 41. 9 (1. 02) (b), F2 : 43. 3 (1. 04) (c), Su : 43. 5 (1. 00) (c), Z2 : 44. 0 (1. 02) (c) ; and with the non-fluoride-containing dentifrice were : Ke : 42. 9 (1. 02) (a), Fj : 44. 7 (1. 01) (b), F2 : 45. 2 (1. 09) (bc), Su : 46. 0 (0. 99) (c), Z2 : 46. 6 (0. 99) (c) (statistical differences were expressed by different letters).