What is the correct angulation of the film during the exposure of intra-oral packets using a film holder?

The correct angulation of the film during the exposure of intra-oral packets using a film holder is parallel to the tooth. When the film is positioned parallel to the long axis of the tooth being radiographed, it allows for the most accurate representation of the tooth's structure on the X-ray. This positioning minimizes distortion and optimizes the image's quality.

In practical terms, this alignment ensures that the X-ray beam is directed properly, allowing for effective capture of the contours and features of the tooth without elongation or foreshortening of the image. It is fundamental for obtaining diagnostic quality radiographs, crucial for assessment and treatment planning in dental practice.