An orthodontic workstation stores a library of virtual three-dimensional brackets in a memory. Each of the virtual brackets has a unique three-dimensional configuration and prescription. Typically, the library of bracket comprises a library of commercially available, off-the-shelf brackets. The workstation further includes an interactive treatment planning program that permits a user to move teeth from a virtual model of the dentition to a proposed set-up. In one possible embodiment, the treatment planning program provides the ability to display a virtual bracket placed on a virtual tooth and change the prescription or configuration of the virtual bracket. The treatment program automatically compares the modified prescription with the prescription information of the virtual brackets in the library and selects a bracket from the library that most closely matches the virtual bracket displayed on the tooth. Thus, the user does not have to use customized brackets. Any deviation in tooth position resulting from a discrepancy between the off-the-shelf bracket and the user-defined bracket can be corrected for by changing the position of the bracket on the tooth or by changing the shape of the archwire.