The goal of this randomized clinical trial is to compare the effect of erythritol air-polishing and conventional polishing following ultrasonic scaling on the relapse of chromogenic tooth staining in children aged 4-13 years attending the Pediatric Dentistry Clinic of Marmara University Faculty of Dentistry for routine dental examination.

The main questions this study aims to answer are:

• Does erythritol air-polishing reduce the relapse of chromogenic tooth staining compared with conventional polishing following ultrasonic scaling?
• Is there a difference in the time to relapse of chromogenic tooth staining between the two polishing techniques?

Researchers will compare conventional polishing (prophylaxis paste and a polishing brush) following ultrasonic scaling with erythritol air-polishing performed using the EMS air-polishing device following ultrasonic scaling to determine whether one method is more effective in preventing or delaying the relapse of chromogenic tooth staining.