New fillings that are placed by your dentist should not be sensitive.
If they are they should not remain that way for long.
Some very large fillings may take longer then others, but
eventually every filling should calm down.
So what exactly is going on when a fillings sensitive?
It has to do with expansion and contraction.
As with most things, when a tooth is exposed to hot or cold
temperatures it will expand or contract accordingly.
If a tooth has never had a filling it will all contract and expand at the same time.
If a tooth HAS had a filling however this is where we may get an issue.
If the tooth and the filling have a different point at which they want
to expand or contract then there can be some discomfort.
Over time this discomfort should go away as the tooth gets used to the filling.
If the discomfort does not go away then the filling needs to be re-done.
If it still hurts then there are some different types of filling materials that can be used.
If it still hurts then other treatments may be needed.
Filling sensitivity is a funny thing.
Someone can get 4 fillings in the same day.
Same filling material.
But only 1 will end up hurting.
It is a real tooth by tooth thing and can drive patients, and dentists, crazy!