After Lex received his electro-shock therapy, you can clearly see the doctor remove the rubber mouthpiece from Lex's mouth. However, after Lionel speaks to Lex, you see a close-up with the mouthpiece once again in Lex's mouth.
When Clark tears through the chain link fence at Belle Reve, you can see where it's going to separate, thanks to a piece of metal that stands out from the rest of the fence.