Slow in responding, sorry. I live in NYC so there are major medical centers galore. I found a doctor who specializes in OLP (and other things) in a practice associated with NYU. He prescribed the usual: a topical corticosteroid, and it has helped. Now to the science:

A layperson like myself isn't allowed to read the medical journals. However, an Australian journal allows us to read old articles and I found one from 2002 which explains the whole etiology and histology of OLP. It's core science and I'm confident that it is still sound information. The most interesting info for me is introduced on the first page and explained in full later: "OLP chronicity [translation: chronic nature] may be due, in part, to deficient antigen-specific TGF-β1-mediated immunosuppression." Now TGF-β1= TGF-Beta 1. So this explains why beta blocker meds may lead to OLP. With a beta blocker like Metoprolol (the drug I'm taking), you are literally blocking Beta 1, the very substance that mediates--or prevents--OLP!

I tried to introduce this info to my cardiologist and my dentist and neither seemed willing to listen. Doctors are not scientists! And some doctors are unwilling to learn from patients.

Here is the link to the paper, The Pathogenesis of Oral Lichen Planus. I warn you, it is very long, difficult, and arcane for a layperson!
https://journals.sagepub.com/doi/10.1177/154411130201300405
I am trying to wean myself off the beta blocker and am taking 75% less of it than a year ago. That strategy, has helped immensely, along with the corticosteroid, but I know I am not out of the woods with this chronic condition.

I've found the toothpaste recommendations interesting and the one I prefer is one mentioned, Cleure brand, which is a bit pricey but worth it. Available on Amazon. This toothpaste is soothing and has no flavor whatsoever. You could enjoy wine, coffee, orange juice immediately after use!

I also swish with Aloe Vera gel and coconut oil, both very soothing. Good luck, everyone. Let's keep the discussion going.