tooth structure has fine grooves or pits which accumulate plaque, not because
the person doesn't brush, but because they're too narrow to allow even one
toothbrush bristle into them. Sealants are used to fill these small
grooves on the chewing surface of the tooth that cannot be adequately cleaned.
To avoid cavities developing over time, a
coating will be brushed on that seals the grooves and pits.