What should be the ideal distance between the X-ray source and the patient?

The ideal distance between the X-ray source and the patient is significant for ensuring image quality and minimizing radiation exposure. A distance of 16 inches is optimal as it provides a balance between maintaining sufficient intensity of the radiation beam for clear imaging while reducing unnecessary exposure to the patient.

When the source is positioned at 16 inches, it helps maintain a good compromise between the size of the radiation field and the sharpness of the image. Closer distances can lead to increased magnification and scatter radiation, which might compromise the diagnostic quality of the radiograph. In contrast, if the X-ray source is further away, such as 24 or 30 inches, while it can reduce exposure, it might also diminish the image clarity due to reduced beam intensity and increased geometric factors.

In dental practice, particularly, positioning the X-ray tube at 16 inches is widely accepted as a standard practice to achieve optimal results in both image quality and patient safety.