Ed Helms may have had to fake looking hungover during his latest film, but there was one acting trick that was authentic: The missing tooth.

In the trailers for The Hangover, the comedian can be seen with a large gap in his grin. That visual is not a result of any advanced prosthetic or computer trickery. His tooth is gone—because he had it pulled out.

“It is totally real,” The Office star revealed. “I have an implant. An adult tooth never came in … and when I was 16, they did a permanent implant.”

Although other options were explored for the effect, Helms and his dentist eventually opted to go au naturale. “We started to do different tests with prosthetics and blacking it out and nothing worked,” Ed explained. “I wasn’t eager to take out my implant because my mouth is healthy, but I talked to my dentist … and he was like, ‘Yeah we can do it!’ My dentist was really into it.”

The Hangover, also starring Justin Bartha, Bradley Cooper and Zach Galifianakis - opened in theaters this weekend.