Ace the BU Dental Radiology Exam 2026 – Shine Bright with Radiant Results!

In the paralleling technique, the film is placed parallel to the long axis of the tooth and the X-ray beam is aimed perpendicular to both. That perpendicular relationship means the beam is essentially at 90 degrees to the tooth and to the film, which is why this setup yields the most accurate representation with minimal distortion. If the angle is not 90 degrees—being more oblique like 60 or 30 degrees, or parallel to the tooth as 0 degrees—the image will show foreshortening or elongation, making measurements unreliable.