How do you immobilize the patient's head for a cephalometric skull radiograph?

The correct method for immobilizing the patient's head during a cephalometric skull radiograph involves using plastic ear rods. These ear rods are specifically designed to help position the patient's head accurately and securely. They are inserted into the ear holes of the cephalometric head frame, which stabilizes the head and ensures that it remains in the correct orientation throughout the exposure. This is crucial for achieving clear and diagnostic-quality images, as even a small movement can lead to distortion or unclear results.

The use of ear rods is particularly effective because it allows for the proper alignment of the X-ray beam with the anatomical structures being examined, ensuring that the radiograph captures the necessary details for diagnosis and treatment planning. Other methods like bite blocks, head straps, or chin rests may provide some stability but do not offer the same precise immobilization and alignment as ear rods specifically designed for cephalometric imaging.