Coach Rick Carlisle informed Wright of the team's decision after Friday night's win over the Boston Celtics, when the D-League all-star's 10-day deal expired.
The Mavericks next will sign guard Justin Dentmon from their own D-League affiliate to a 10-day deal, most likely finalizing a contract with the Texas Legends' leading scorer Monday, sources with knowledge of the situation told ESPN.com's Marc Stein.
Dentmon was averaging 26.0 points through 22 games with the Legends and was the D-League's MVP last season while playing for the San Antonio Spurs' affiliate in Austin, earning call-ups from both the Spurs and Toronto Raptors.
Wright, who had left the locker room before the media were allowed in Friday, was diagnosed with MS while playing for a Turkish professional team last year. After going to training camp with the New Orleans Hornets, Wright earned a D-League all-star bid while playing for the Iowa Energy before being called up by the Mavs last week.
Wright, a 23-year-old Georgetown product, appeared in three games for the Mavs, playing a total of four minutes. He scored one basket in a March 15 win over the Cleveland Cavaliers, and Darren Collison made sure Wright got that ball to keep.
"He's been an inspirational figure to a lot of people," Carlisle said. "He's an NBA-caliber player. There's no doubt about that. You do what he's doing -- playing a professional sport with MS -- that's going to be something that a lot of people pay attention to. It shows his motivation, his determination, but it also shows the progress that's been made in that area.
"It's going to give people hope. That's a great thing."
In the wake of Rodrigue Beaubois having hand surgery, which likely will sideline him the rest of the season, Dallas has decided to use its 15th roster spot to get to know various young players for potential down-the-road signings.
That means, sources told ESPN.com, that the Mavs likely will bring in another player on a 10-day basis after Dentmon's trial.
The Mavericks have been unable to give Beaubois' minutes to 2012 first-round draft pick Jared Cunningham because the rookie guard -- who technically remains on assignment with the Legends -- has been plagued by a knee injury. Cunningham has appeared in just eight games with the Mavs this season, logging 26 minutes.
ESPN.com senior writer Marc Stein contributed to this report.