Cast
Harry Carey
Professor John C. Warren
Louis Jean Heydt
Dr. Horace Wells
Grady Sutton
Homer Quimby
Thurston Hall
Senator Borland
Hank Bell
Onlooker (uncredited)
William Demarest
Eben Frost
Edwin Maxwell
Vice-President of Medical Society
Hank Worden
Morton's Sign Painter - replaced Roscoe Ates (uncredited)
Porter Hall
President Franklin Pierce
Franklin Pangborn
Dr. Heywood
Harry Hayden
Judge Shipman
Victor Potel
First Dental Patient
Roscoe Ates
Morton's Sign Painter - replaced by Hank Worden (uncredited)
Byron Foulger
Morton's Clinic Manager (uncredited)
Joel McCrea
William Thomas Green Morton
Betty Field
Elizabeth Morton
Julius Tannen
Dr. Charles T. Jackson
Torben Meyer
Dr. Dahlmeyer
J. Farrell MacDonald
The Priest
Franklyn Farnum
Massachusetts Medical Society Man (uncredited)
Arthur Hoyt
Presidential Secretary (uncredited)