PT Palpatine's "Scars"

I'm just not seeing teeth burning and nails growing and becoming unkempt. But to sum up the article with one important quote:

I don't know, that seems pretty definitive.

 

The exact words of the quote in question (page 55 of Absolutely Everything You Need to Know:

During a fight with Mace Windu, Palpatine fires Force lightning at his opponent, who reflects the dark energy back at the Sith, revealing his true, evil nature. Palpation's face melts and his eyes, nails, and teeth turn a sickly yellow. After he becomes Emperor, he hides his disfigured appearance in Imperial propaganda broadcasts.

 

As in, he had been evil on the inside up until that point, and now it was making that evil nature his appearance. Literally the line right after you underlined says his face melted and that his eyes, nails, and teeth turn yellow from the dark energy being reflected back at him. he then has to hide his disfigured appearance for when he does propaganda broadcasts.

There's no mention of a dark side "mask" falling off. Plus, if he could mask his appearance before, why wouldn't he just do it again? We already know canonically that he doesn't let the public see his disfigured face. His propaganda broadcasts use younger images of him from before he was disfigured.