How should the rubber cup be positioned during a coronal polishing procedure?

The rubber cup should be positioned flat against the tooth during a coronal polishing procedure to achieve the most effective cleaning and plaque removal. When the cup is flat against the tooth surface, it allows for maximum contact, which enhances the polishing effect. This positioning enables the cup to glide smoothly over the enamel, effectively removing stains and debris without causing discomfort to the patient.

Using a flat angle also helps to distribute the polishing paste evenly across the tooth surface, minimizing the risk of abrasion to the enamel and ensuring a uniform finish. This technique is particularly important in achieving optimal results in a gentle and controlled manner.

In contrast, other positions, like angled or curved, may reduce the effectiveness of the polishing process or increase the risk of damaging the tooth structure or surrounding tissues. Therefore, maintaining a flat position is fundamental to proper technique during coronal polishing.