Hail to the Teeth is the eleventh episode of Season 31.
Homer and Marge attend Artie Ziff's wedding and become quite uncomfortable when they realize that his bride-to-be is a clone of Marge. Meanwhile, Lisa grapples with the misogynistic implications of the immediate popularity she receives after getting her new Invisalign braces.
A man tells Lisa that if she smiles more, she would be more popular. When she finds out she needs braces for a second time, once she gets the top half done, she cannot stop smiling physically. Her new popularity motivates her to run for school president against Dubya Spuckler.
Meanwhile, Homer and Marge are forcefully invited to Artie Ziff's wedding. They find out Ziff's new wife is a clone of Marge, which reveals he has still not gotten over Marge and they show him that it is not right. However, he still has many clones of Marge in the end.
As Lisa seems to have locked in her position as new school president, before the school debate, she has her bottom braces put in, which leaves her with a frowning expression. She tries to show up on a computer screen to make her seem smiling with the help of Martin Prince, but the editing goes awry and the audience favors Dubya in the end, and he is elected president of Springfield Elementary.