Lehtonen has missed five games because of a groin injury after leaving in the first period of a 4-3 win over Vancouver on Feb. 15.
The 29-year-old Lehtonen from Finland was among the NHL leaders in wins when he was injured. He is 7-2-1 with a 2.12 goals-against average and a .934 save percentage.
To make room on the roster, the Stars sent goalie Cristopher Nilstorp to Texas of the American Hockey League. Nilstorp is 1-3-1 with Dallas and 17-10-5 with Texas this season.