Millions of television viewers may have been shocked to see Janet Jackson's naked breast during Sunday's Super Bowl (search) halftime show, but not Dr. Howard Dean (search), M.D.

Asked about the incident while campaigning in Washington state, site of Saturday caucuses, the Democratic presidential hopeful reminded his questioner that he's a medical doctor.

"It's nothing I have not seen before," Dean said.

At the end of a duet Sunday, Justin Timberlake snatched off part of Jackson's bustier, revealing a breast covered only by a sun-shaped "nipple shield" to some 89 million viewers.

A spokeswoman for Jackson said a red lace garment was supposed to remain when Timberlake tore off the outer covering. But widespread questions remained about the intent. The Federal Communications Commission is investigating.