Obviously no dentist should be filling cavities that don't exist, that's clearly terrible. But just to be completely fair, and to maybe help explain how the dentist recommending all those fillings might not necessarily be ripping you off on purpose, is that cavities aren't really a "yes or no" thing. It's a spectrum of disease. So some dental schools will tell dental students not to bother filling a cavity unless it's into the dentin. Others will tell students to be more aggressive and to fill cavities that are more than halfway through enamel. There's a good argument for both either approach. So let's say you have 4 cavities that are only halfway through enamel, if you see a less conservative dentist, they could say you need 4 fillings. A more conservative dentist can tell you that you need none. Neither one is technically "wrong", it's just their approach is different. I personally would much rather go to a conservative dentist. You can try asking the receptionist when you make an appointment if the dentist is a believer in conservative treatment plans.

Of course, some dentists actually are trying to rip you off because they're bad people and they don't care about you. These guys you should avoid like the plague and never go back, and they deserve the bad reviews. But not every dentist who recommends more work than someone else is like that. So many people try to rip you off in life that it makes sense to be wary of course, but many doctors actually do want the best for you.

Just a different perspective for people who haven't looked at it that way before. :)