No, I don't have to exfoliate anything anymore, with a toothbrush or otherwise. As to your other question, I'm afraid I can't answer it satisfactorily. I don't keep my lips slathered in the stuff anymore--but I do moisturize them, like anybody else. Keep in mind that normal people lick them throughout the day to keep them moist--and I don't think there's any sort of drawback to that, even to us. But still, I've developed the habit of not licking them, due mostly to the fact that that's usually touted as one of the causes of this "condition" (wound), so I continue to moisturize them with chapstick. If you lick them, I'm sure you won't need to continually apply anything to them. And I think it's perfectly safe to lick them. We bit off skin, or burned it off with some chemical we ingested or rubbed on our skin, and it's just trying to regenerate that skin. We didn't lick it off, unless our saliva's made of acid.
That's all that rawness is, by the way. Like any other scrape or minor burn, it's just missing a protective covering--the skin. And like any other scrape or minor burn, scabs try to cover it so as to heal it. And if left alone, I believe it will eventually heal on it's own, but because of the location of the wound, the scabs can't form properly, and the healing slows down to a crawl, taking months, even years. I believe this is how daniki (or whatever her username was) actually healed--the stuff she was taking was just incidental. If you look at her pictures, she left those things alone. Look also at Daniel--he made tiny, tiny progress leaving them alone. By tiny, I mean certain portions of his lips DID stop peeling. But it was only when he started to moisturize them, and not obsess about leaving the scabs on them, did he really heal.
To answer your question, no, I don't have any buildup whatsoever on my lips when I wet them brushing my teeth or after I shower. 0. Your rawness will go way--if you diligently apply the aquaphor as I've instructed--within 3 days. This is because you will see new skin beginning to form; and you'll know it's new skin if you look at it under the light and you see vertical lines or grooves forming from top to bottom. Just remember that during, I believe. the fourth or fifth day, the new skin will have a weird white covering of dead skin or something that you'll notice after your brush your teeth. Gently brush it off, being careful not to damage the new skin.
Lastly, I want to reiterate: don't brush your lips too hard. When I mean gentle, I mean barely touch it. And brush slowly. That way you ensure whatever comes off was not a part of your lip.