In the paralleling technique, how is the central ray oriented relative to the tooth and receptor?

• A. Parallel to Both the Tooth and Receptor
• B. Perpendicular to Both the Tooth and Receptor
• C. Parallel to the Tooth and Perpendicular to the Receptor
• D. Perpendicular to the Receptor Only

Answer: (B)

In paralleling technique, you place the receptor parallel to the tooth’s long axis so the image can be accurate and undistorted. The central ray is directed perpendicular to the receptor, and because the receptor is aligned with the tooth, this makes the beam perpendicular to the tooth as well. This perpendicular relationship minimizes foreshortening or elongation and gives a true representation of the tooth. If the beam were not at a right angle, distortion would occur, compromising image accuracy.