First I want to say kuddos to instymp for finding time to smoke 10 bowls a day, that is a feat. Most I have done is 3 bowls on a lazy saturday.
And I fall into the category that cancers have many triggers, stress quite possibly one of them. I feel my pipe smoking time helps reduce my stress, which is better for me. Last dental check up they didn't say anything about smoking, but I also do not offer it up.