What should be used after applying flour of pumice to ensure an effective polish?

Using a fine polishing agent after applying flour of pumice is essential for achieving a smooth and shiny surface on the teeth. Flour of pumice is a mildly abrasive substance that helps remove surface stains and plaque but may leave the enamel somewhat rough after its application. Following up with a fine polishing agent helps to refine that surface by filling in any micro-scratches created and smoothing out any rough areas.

This additional step is crucial because while flour of pumice is effective for initial cleaning, it does not provide the final gloss or luster that can be achieved with a finer polish. The fine polishing agent typically contains smaller particles that can reach into the intricate contours of the tooth surface, providing a polished finish that enhances the aesthetic appearance.

In contrast, using another coarse grit abrasive might further roughen the surface instead of smoothing it out, while rinsing with water could remove some of the pumice but won't contribute to any further polishing effect. A medium grit abrasive would also not effectively provide the final fine polish needed after the initial abrasive action of the flour of pumice. Thus, the use of a fine polishing agent ensures that the final step in the polishing process achieves the desired shine and smoothness.