the mean fluoride content of plaque in sydney ( 22.6 , s.d . = +/- 16.8 parts/10 ( 6 ) ) and yass ( 25.6 , s.d . = +/- 16.4 parts/10 ( 6 ) ) differed significantly ( t = 2.27 , p less than 0.05 and t = 3.30 , p less than 0.02 , respectively ) from that in katoomba ( 13.5 , s.d . = +/- 8.3 parts/10 ( 6 ) ) .
C0016327
fluoride
C0011389
plaque