What will happen if you don't take care of your teeth?

If you are American, probably the same thing that happens if you do take care of your teeth. Almost everybody has to have dentures around retirement time. Everybody in USA, that is. In other countries it might be different. People who don't eat American diets have natural teeth for their entire lives. Nobody in America seems to care about diet, they just want you to "take care" of your teeth, and they are awfully casual about explaining how to do that. They can't even agree on whether you should brush up and down, back and forth, or round and round.