this is what my Dr said to me..."Unfortunately, nicotine is the main culprit and health risk, so if it contains nicotine, then the risk should be the same. If it doesn't have nicotine, what's the point? Better to check on a pencil or celery sticks! (As a former heavy smoker, I can relate though.)"
Don't mean to sound flip but, seriously, he/she needs to go back to school or at least to youtube and watch all the videos by internists, cariologists and other specialties one of whom is the Chief of Staff, UCLA Santa Monica Hospital... name is Dr. David Baron... its a two part video. Might want to send your doc the links to it.