Isabella looks like Dr. Doof's dentist | "Droogenfest"

At the end of the episode "Droogenfest", Isabella awards her troop "Preventing-an-International-Incident" Patches; she also awards Doofenshmirtz a “Good-Job-Cleaning-Up-Your-Own-Mess” patch after he confessed that he invented the Droogen-Chocolate-Swap-Inator that caused the entire situation. The episode closes with a gag showing Doofenshmirtz’s dentist—who indeed looks just like Isabella, with a pair of pink googles resembling her bow and a beard that resembles her long hair.