Glasgow No. 8 Dempsey joins the pack alongside lock Jonny Gray, included after Grant Gilchrist was banned after being sent off in a defeat by France last month.
Dempsey made his Scotland debut last year after a change in world rugby's eligibility rules allowed the Glasgow back-row to switch allegiance from his native Australia.
The 28-year-old will wear the No. 8 shirt, with Matt Fagerson moving to fill the flanker position vacated by Hamish Watson.
Scotland's third-round defeat by France ended their hopes of a Grand Slam.
But they will claim their first Triple Crown since 1990 if they win in Edinburgh against an Ireland team bidding for a clean sweep.
The Triple Crown is the reward for beating all three of the other "home" nations in any one tournament, comprising England, Scotland, Ireland and Wales.
Scotland (15-1): Stuart Hogg; Kyle Steyn, Huw Jones, Sione Tuipulotu, Duhan van der Merwe; Finn Russell, Ben White; Jack Dempsey, Luke Crosbie, Jamie Ritchie (capt); Jonny Gray, Richie Gray; Zander Fagerson, George Turner, Pierre Schoeman
Replacements: Fraser Brown, Jamie Bhatti, Simon Berghan, Scott Cummings, Hamish Watson, Ali Price, Blair Kinghorn, Chris Harris
Coach: Gregor Townsend (SCO)
