Needed knowledge about keratosis. This?

Both my buccal mucosa and labial mucosa are little bit pigmented and they're keratanised, means they feel granular or like sand paper when you linger your tongue or touch it with fingers, I have been to dentists they said its normal pigmentation, but my question is more about keratosis, what all condition can cause chronic keratosis without any whiteness, only roughness on epithelial layer.. Can any STD or TB or any other infection cause this? Let's exclude OLP from D.D, can there be other causes? Please enlighten me, and how to diagnose it accurately, i hope this is not dysplasia or cancer, also see the Lichenoid reaction type marks present on cheek. Please guide me what can it be, and what are the possible infections which can cause this? I have attached a pic of my buccal mucosa. Note: please forget pigmentation, main question is about keratosis and marks, and yes i have already confirmed clinically, there's no tooth trauma.