you have to make sure your dentist doesn't use fast drilling... better use special gel to remove plaque. slow drill not so bad but still better to avoid. because fast drill shakes all tooth structure weakening it, later it die and ready for tooth canal..
composite fillings are good because they dont contain any kind of metal.
the right dentist might not need even to drill, just fill up the tooth hole. That why I think better to go to biological dentist who will avoid drills and damaging treatments as much as possible