The spindle in a tofflemire retainer primarily moves through what part?

The spindle in a Tofflemire retainer primarily moves through the vice. The vice is the main component of the Tofflemire retainer that holds the matrix band securely in place while it is being adapted around the tooth. The design of the vice allows for the vertical adjustment and stability of the matrix band, which is crucial for creating a proper anatomical shape for the restoration.

In the context of the other components, while the guide slot, outer nut, and inner nut play roles in the overall function of the retainer, they do not serve the primary function of facilitating the movement of the spindle. The guide slot is designed for positioning and guiding the matrix band but does not allow for any significant movement of the spindle. The outer and inner nuts are used to tighten or loosen the assembly but do not directly engage with the spindle's motion. Thus, the correct answer centers around the vice as the critical point for spindle movement in the configuration of the Tofflemire retainer.