What is a contraindication for using ultrasonic scalers?

Using ultrasonic scalers can be contraindicated in patients with certain medical conditions, particularly those with a pacemaker. This is due to the potential for electromagnetic interference with the functioning of the pacemaker. Ultrasonic scalers generate high-frequency vibrations, and these vibrations may disrupt the electrical signals of cardiac devices, leading to possible health risks for the patient. Consequently, dental professionals must carefully evaluate a patient's medical history and current health status before using ultrasonic scaling instruments to ensure their safety and well-being.