The method and apparatus provides a system for automatically determining the location of individual teeth within an electronic model image of a patients mouth. The electronic model image allows for manipulation of the electronic model image by end users. Possible horizontal cut lines are determined within a horizontal plane cut through the electronic model image corresponding to possible separation lines between the teeth. Possible vertical cut lines are then determined within a vertical plane cut through the electronic model image corresponding to possible separation lines between teeth. The system then automatically determines the locations of individual teeth using the possible horizontal cut lines and the possible vertical cut lines.