Читать книгу Orthodontic Treatment of Impacted Teeth - Adrian Becker - Страница 72

As dentists, we are used to seeing periapical radiographs of individual teeth and, provided that the teeth concerned are erupted and in the line of the arch, these radiographs have many advantages. However, in this view the X‐ray tube is not directed in either the true horizontal, true vertical or true lateral plane. Aside from radiography of the mandibular posterior teeth, the tube is always tipped at an angle to one or more of these planes. For an erupted tooth this is unimportant, since the third dimension is supplied by direct vision within the mouth. However, while it gives a good 2D representation of the tooth, this view has limited value when visualization of an unerupted tooth is required in the three planes of space.

Fig. 4.3 (a) The periapical view shows an impacted left maxillary central incisor, due to an inverted, unerupted, supernumerary tooth. The deciduous tooth is over‐retained. Accurate diagnosis of the height of the impacted tooth in the alveolus is not possible to determine from this view. (b) The anterior maxilla seen on a lateral cephalometric radiograph shows the high impacted central incisor (arrow) and its bucco‐lingual location, facing the labial vestibular sulcus. (c) The parallel intra‐oral photographic view at surgical exposure. The radiograph has been laterally inverted to simplify comparison.

Courtesy of Dr D. Harary.