I haven't seen any studies about it, but I would bet you that smoking contributes to weaker teeth or gums or something. I've always had great teeth, but suddenly (in my 60s) I'm getting cracks in the molars. I've already had to have one pulled, and now I have another one on the way out. It suddenly began to hurt yesterday and the pain brought me to my KNEES! I'm not posting this as a plea for sympathy, but to say can you imagine smoking when you have dental pain? The sucking in of smoking would be excruciating! It's a good thing I'm retired because I look kind of funny eating and drinking with my head tilted to the good side. I go tomorrow for the extraction. I would have gone in my pajamas this morning if they'd have had an opening. Just so glad I don't have to try to smoke with this thing.