The American DAT has Bio, GChem, OChem, PAT, Reading and Quantatative.
This test is computer based.
The Canadian DAT has Carving, Bio, GChem, PAT and Reading.
This test is paper.
To apply to dentistry schools in Canada you need a Canadian DAT score. To apply to US you can use either one. However the Canadian DAT is only offered 2 times a year while the American is offered well almost everyday.