In the Georgian era, some people used birch twigs, chalk and salt to clean their teeth, but I am not sure how universal a practice this was. Certainly, people still had very bad teeth. If you recall from my post about tea, you might remember that the Georgians ate a lot of sugar, or at least they did if they could afford it. Not only did they put excessive amounts of sugar in their tea, they also ate cake constantly. They ate cake for breakfast; I kid you not. They ate little cakes with their tea. They didn't have lunch, so they just snacked on cake. This rotted their teeth, obviously. At least, if you could afford sugar it did.
Resulting infection was, I believe, what caused death by teeth. There were no anti-biotics, and dental care was pretty horrific. In fact, I imagine going to the dentist might actually be more dangerous than not, given that people didn't know about germs and definitely did not sanitize anything, even if they did clean it, which is questionable.
The only real treatment was to pull the tooth. If you were rich, you could be drugged with laudanum first; Chloroform came later. Once the tooth was out, then what? Did you just go around with a tooth missing? You could, I suppose, but preferable were false teeth. They didn't make artificial teeth out of plaster like they do now. They used dead people's teeth.
The market for teeth was quite a hot one. You could even wear dentures made of a whole set of a dead person's teeth. They wouldn't fit very well, but it's better than dying of toothache, and better than toothlessness.
The most popular teeth were those of fallen soldiers from the war in France. It was considered patriotic to wear a soldier's teeth. People would scour battlefields scavenging for jewelry and buttons and money, but they also went about taking out the soldiers' teeth which they would sell back to the English. I don't see at all how it would be patriotic to participate in this atrocity by purchasing such teeth, and I don't know how anyone could verify the source of the teeth, but I suppose they just wanted to keep the memory of the soldiers alive and near to them... in their mouths.
(Follies Past: A Prequel to Pride and Prejudice, is a novel by Melanie Kerr. Expected publication date is October 31, 2013. Until then, I will be posting things I learned in the course of my research and of my life so far as a geek. Follow me on twitter @FolliesPast.)