I had a toothache, so I didn't want to read this article :) It's gone now. Great information. I do have a question. While you explain that cavities are not contagious (one person to another), are they though from one tooth to another? That is, if I have a cavity in my lower first molar, can that decay spread to the next molar, or does it just spread within one tooth?

Thanks for the the answer (I'll get my tooth fixed when COVID isn't so prevalent).