Long-time posters have heard this before, so I am responding to the "Why?" posts of the new members. None of us will ever know the causes of our or our loved ones oral cancers, but it is natural to want to know "why" so we can perhaps prevent recurrences by reasonable elimination of what may be causing the cancers, for example, "stop smoking". Poster Linda Rose and myself have wondered about the metal (esp. mercury) in fillings and crowns. She mentioned a site "toxicteeth.org" where doctors and researchers have been mounting a campaign to do further study on this possible link, keeping in mind this would be an extremely small percentage of OCC patients whom this could affect. I will use my husband as an example. He has had 3 or 4 SCC cancers (although the lip cancers are probably sun related) and they all seemed to occur right by a filling or crown, plus he had leukoplakia and lichen planus (laser treatment eliminated most of that)so there could also be a causal effect between the amalgams and the lichen planus/leukoplakia...a "bridge" between the two, causing cellular changes. He has since had all his crowns and fillings (yes, fillings!) replaced with porcelain, and has had no problems since then. I am not saying this has solved his problems forever or even if there is connection, but I do know several of his doctors have all stated in recent appts that "his mouth has never looked better". I pray this continues, and I understand this isn't the answer for most people but it seemed to help Dick, who, btw, never smoked, not a drinker, and no HPV.
Hope this addresses one small part of this question-that-can't-be-answered-simply.