The invention provides a method of manufacturing a series of tooth positioners for incrementally repositioning one or more teeth of a patient from an initial configuration to a final configuration via one or more intermediate configurations. The method uses a composite model of the patient's teeth in the initial configuration, the composite model having a base and one or more discrete model teeth. Each model tooth includes a crown portion and a root portion and is mounted on the base in a tooth mounting portion of the base formed from a mounting material in which the root portion can be imbedded and retained in position but which can allow movement of the root portion through the tooth mounting portion upon application of a force to the crown portion of the model tooth. In the method, the position of one or more of the model teeth is changed to reconfigure the composite model to a first intermediate configuration. A negative impression of the first intermediate tooth configuration is then made. The position of one or more of the model teeth in the mounting portion of the base is then changed again to reconfigure the composite model to a second intermediate or a final configuration. A second or final impression of the second intermediate or final tooth configuration is then produced. The impressions taken from the model can be used to make the series of positioners.