Interesting. The chronic irritation thing here in the US has never been proven, though speculated on greatly, the subjects are mostly denture wearers, and as a dentist you know there is no such thing as a happy lower denture patient, particularly as they age and the ridge gets smaller. Those things move around against the soft tissue a lot. But any look at the situation here (as a cause of malignant transformations) has neglected to remove bias. Most reports have not excluded (or properly documented) other known risk factors in their published opinions and patient populations examined, of patients such as tobacco use.

You would think that chronic irritations mostly likely cellular changes would produce hyper keritosis to protect the tissue. We see this commonly as a linea alba on the cheeks of patients, also from chronic nighttime contact with the juncture of the maxillary and mandibular arches.

I wish that we had a peer reviewed paper that addressed the cellular changes from things like this since in the OC community people are very divided about it.