What do they do with a cavity and how long dose the naming last for?

I've had four cavities filled over the years and the numbing does not last too long. Maybe a couple hours.

''What Happens When You get a Filling?
If your dentist decides to fill a cavity, he or she will first remove the decay and clean the affected area. The cleaned-out cavity will then be filled with any of the variety of materials described above.''

First they give you novacaine, then they use the drill to remove the cavity, then they fill it up. It is not so bad. The novacaine usually lasts for a couple or a few hours.

IF the tooth needs to be numbed, they will do that first. The shot really does not hurt. It is not like a shot in your arm..most people do not feel the needle at all.

Secondly, they will take a tiny drill and take out the part of the tooth that is decayed.

Then they will fill the tooth with white resin material or a metal filling.

Usually, the numbing wears off in 1 to 2 hours.