For your teeth remaining free of caries for years: Fissure
sealants
A fissure means a deep crack at the
dental surface that is very difficult to clean
since the toothbrush often does not get into those cracks at
all.
Therefore, within the fissure sealant process
the teeth are filled with plastics in these regions to protect the
teeth against inclusions of plaque and leftovers that may cause
caries.

This is how the first caries develops

After fissure sealant, the tooth is protected