What is the proper patient positioning for bisecting angle radiography?

The proper patient positioning for bisecting angle radiography requires the maxillary arch to be in line with the ala-tragus line, which is an imaginary line from the ala of the nose to the tragus of the ear, running parallel to the floor. This positioning helps to ensure that the central ray of the X-ray beam intersects the bisecting angle formed by the long axis of the tooth and the plane of the receptor.

By following this positioning guideline, the resulting radiographs will effectively capture the necessary detail and minimize distortion in the images of the maxillary teeth. Proper alignment is crucial for achieving accurate diagnostic quality images, which is fundamental in dental radiography.

Each of the other options presents positioning that would not effectively facilitate optimal imaging. For instance, tilting the maxillary arch downwards or placing the mandibular arch in an inappropriate orientation could lead to overlap or distortion, making it harder to interpret radiographs accurately for diagnostic purposes.