Plouffe batted .200 with 10 RBIs through 18 games with the Twins.
"[Dinkelman] has worked very hard and played very well down there," Twins manager Ron Gardenhire said. "It's kind of a tough move. Plouffe is a great kid. He has had a little bit of a rough time up here, so it's hard sending him down, because we like him so well. On the flip side, giving Brian Dinkleman a chance is pretty exciting."
In a procedural move, the Twins transferred Joe Mauer to the 60-day disabled list, which puts him in line to be eligible for duty on June 12.