One of my chins keep gnawing on my Ferret Nation Cage bars. The other female I have does the same but she just kinda rests her teeth on the bars, not full blown "I'm gonna chew these bars till I get out" like my other female. Is this okay? Or should I wipe the bars with white vinegar so she won't want to? I'm worried she will chip her teeth. She has plenty of wooden (pine) accessories to chew on and hanging wooden toys as well.