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In the maxillary arch, the nose and forehead interfere with the positioning of the X‐ray tube close to the area to be viewed. The best that can be achieved by positioning the tube close to the face is an oblique, anterior, maxillary occlusal view of the teeth, which is perhaps better described as a high or steeply angled periapical view (Figure 4.2). This view will shorten the apparent length of the roots and will be a far cry from the cross‐sectional view that is so easy to achieve in the mandibular arch. The central ray passes through cancellous bone rather than the compact bone that is found in the mandible, so detail is usually good, although not as clear as with the periapical view.

Fig. 4.2 A diagram showing incisor inclination, receptor position and central X‐ray beam, differentiating the periapical view, the anterior (oblique) occlusal view and the true vertex occlusal view.

Source: Reproduced from previous edition. Adrian Becker, The Orthodontic Treatment of Impacted Teeth, 2nd ed., 2007 with the kind permission of Informa Healthcare – Books.