What is the recommended angle for the polishing cup against the tooth surface?

The recommended angle for the polishing cup against the tooth surface is a slight angle, typically between 10 to 15 degrees. This angle is ideal because it allows the polishing cup to make contact with the enamel effectively while minimizing the risk of harming the gums or the tooth surface.

At this angle, the polishing cup can achieve efficient stain removal and plaque reduction without applying excessive pressure, which could lead to abrasion or discomfort. Maintaining a slight angle also enhances the effectiveness of the polishing process, ensuring that the cup distributes the polishing paste evenly across the tooth surface, leading to a smoother and shinier finish.

In contrast, other angles such as a right angle (90 degrees) can create more friction and increase the risk of damaging the periodontal tissues. A vertical position might focus too much force on a single point, risking injury to the tooth or gum. Similarly, positioning the cup flat parallel to the gum line may not effectively polish the tooth surfaces, as it reduces the contact area required for effective cleansing. Hence, the slight angle is the optimal choice for safe and effective coronal polishing.