The Hurricanes were looking for help on the blue-line after losing veteran Bret Hedican to injury last week, joining the likes of Frantisek Kaberle and Tim Gleason on the sidelines and leaving Carolina short-handed.
"With some uncertainly concerning when our injured defencemen will be able to return, we needed to make this move now," Hurricanes GM Jim Rutherford said in a statement. "Dennis will be a good fit for us on defence. We thank Kevyn for his good service during his years in Carolina."
Seidenberg, 25, had been a healthy scratch in recent games with the Coyotes. With Nick Boynton set to come back Tuesday night for the Coyotes after missing six weeks with a broken foot, Phoenix needed to move a blue-liner. Seidenberg had one goal and one assist in 32 games with the Coyotes this season.
The German has 33 points (8-25) and 56 penalty minutes in 158 career NHL games with Philadelphia and Phoenix.
Adams, a checking centre, had 72 points (38-34) in 300 games with the Hurricanes over the past five years. He has two goals and two assists in 35 games this season.