Re Chronic irritation causing cancer of the tongue

I am a dentist with 25 years of experience. i had SCC of the (L) lateral border of the tongue 8 years ago (at age 43), which was surgically and successfully removed (twice). I have never been a drinker or a smoker.
In my opinion, there is no doubt that chronic irritation can cause SCC. I have been �nipping� and biting my tongue for a long time, causing an ulcer on the tongue, which had been biopsied twice (with a negative result both times) previous to the SCC diagnosis.
Here is my theory. I have a narrow palate, courtesy of 2 upper premolars extraction when I was in my teens. The narrow arch had not accomodated my tongue well, as was shown by scalloping on the lateral borders of my tongue. Scalloped tongue is a tell-tale sign that the upper arch is too narrow. It follows that when the tongue �appears� to be too big, it is very easy to bite the tongue inadvertently during the course of normal talking, eating and swallowing. Furthermore, i have been nipping my tongue while I was asleep, my wife has frequently heard my teeth �clanking� together while i was asleep. My understanding is that when the tongue lodges in between the teeth, it prompts a proprioceptive reflex for the mandible to rapidly elevate, brought on by the receptors in the periodontal ligaments of the teeth. This is a similar action to the knee jerk reaction when the knee is tapped. When the teeth chronically irritate the tongue, it is feasible that there would be cellular changes in the tongue tissue.
So there is another reason not to extract teeth for orthodontic reasons. Extractions will only further collapse the already underdeveloped arch.