Enamel loss ( SEM ) values for other European products and the reference control ( active agents ) were : Meridol ( ) : ( 1,400 ppm F as AmF + SnF2 ) 12.0 m ( 1.47 ) ; Colgate ( ) Cavity Protection : ( 1,450 ppm F as SMFP + NaF ) 12.9 m ( 1.66 ) ; Odol med 3 ( ) ( 1,400 ppm F as NaF ) 14.2 m ( 1.49 ) ; Elmex ( ) ( 1,400 ppm F as AmF ) 14.5 m ( 1.76 ) ; Colgate ( ) Enamel Protect : ( 1,450 ppm F as NaF + KNO3 ) 16.3 m ( 2.02 ) ; Lacalut ( ) aktiv : ( 1,400 ppm F as AlF3 ) 18.5 m ( 1.71 ) ; Sensodyne ( ) ProNamel ( ) : ( 1,450 ppm F as NaF + KNO3 ) 20.5 m ( 1.26 ) ; Crest Cavity Protection ( 1,100 ppm F as NaF , reference control ) 22.00 m ( 2.04 ) ; and Mentadent ( ) : ( 1,450 ppm F as NaF + Zn citrate ) 22.3 m ( 0.63 ) .