O'Rourke did indeed share video of his hygiene appointment in Texas as part of an Instagram story on Thursday.
Twitter was quick to recoil from the image, with people asking their fellow Twitter users to stop retweeting the view.
"OK... jumping off twitter for a bit in the hopes 'Beto-Went-To-The-Dentist-mania' will simmer down," wrote political reporter Jason Hancock.
O'Rourke unsuccessfully ran for the US Senate in 2018, but emerged as a charismatic star for the Democratic party.
The out-of-context image traveling around Twitter fails to tell the whole Instagram story. O'Rourke, 46, is talking to a series of people who live along the US-Mexico border about their experiences. His dental hygienist, Diana, is from El Paso.
O'Rourke asked Diana what she wants people to know about life along the border. "It's a beautiful community. We all support each other. We love each other," she told him, saying it's a wonderful place to grow up.
The image seems to be triggering dentist fears. "I have such a dentist phobia that I'm going to have to get off Twitter until this ridiculous Beto thing is finished. Seriously, shuddering over here," wrote Twitter user Suz.
Not everyone was grossed out. Some shared their thoughts on both dental hygiene and living along the border.
"Beto is talking to people about their experiences living at the border. I myself took trips to the dentist from Texas to Juarez without incident growing up. Most everyone I knew went back and forth across the border as well," wrote Twitter user marshy.
O'Rourke's Instagram story comes during a time of political tension surrounding the government shutdown and President Donald Trump's insistence on building a border wall between the US and Mexico. It's just that O'Rourke's pearly whites may be blinding some people to his message.
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