The most desirable finish of a composite restoration will be achieved by the use of which item?

A mylar matrix strip is designed to provide a smooth and polished surface for composite restorations. When placed properly against a composite material, it helps to achieve a desirable finish by preventing the composite from sticking to the matrix and thereby facilitating a more even and sleek surface. The properties of the mylar strip, combined with its flexibility and smoothness, make it an ideal tool for creating a polished look that enhances the aesthetics of the restoration.

In contrast, polishing cups and points are more suited for final finishing rather than achieving the initial desired shape and contour of the restoration. While diamond instruments and carbide finishing burs are effective in shaping and preparing restorations, they may not provide the ultra-smooth finish that a mylar matrix strip can offer. The roughness left by bur or instrument marks can detract from the aesthetic appearance, making the mylar matrix strip the ideal choice for achieving that polished, desirable finish.