Many years ago I needed a root canal following a damaged tooth/root. In recovery from the root canal I was put on antibiotics as fairly standard procedure. I swear over the coming months and now years since then that was the cause of the sebb dermatitis on my face.
I've wondered if perhaps the antibiotics messed with my gut, which has caused it. But as many dermatologists say they don't know of a cure but think its a multitude of things, one of which being gut microbiome focused.