What causes the mesio buccal root of upper first molars to appear elongated in an X-ray?

The appearance of the mesio buccal root of upper first molars as elongated in an X-ray image is a result of the vertical angulation applied during the radiographic exposure. When the vertical angulation is too small, the cone of the X-ray beam is directed improperly. This can distort the image, often leading to the roots appearing longer than their actual size due to foreshortening.

In contrast, proper vertical angulation allows for a more accurate representation of the tooth's anatomy, while excessive vertical angulation can result in distortion that makes the root appear shortened. Therefore, understanding the proper angulation in radiography is essential for obtaining accurate images that can effectively aid in diagnosis and treatment planning.