I wasn’t sure what this fellow was actually called and had mistakenly been calling him zipper face since he sort of resembles a popular Halloween costume. After searching about a bit I finally found his real name, the venerable Doctor Tongue.
Doctor Tongue is one of the first zombies we see in Romero’s Day of the Dead. He’s a horribly deformed zombie with a face that’s been seriously messed up. His lower jaw is partly missing and his teeth are all messed up with his tongue lolling out and his face split in the middle. He probably ended up that way from a blast or a chop to the face. No matter what though, if you see him coming, head the other way!