title: Evaluation of the panoramic image formation in different anatomic positions.
abstract: The aim of this study was to determine size, shape and position of the image layer by evaluation of the radiographic image formation in different anatomic positions. A customized phantom was made of a rectangular acrylic plate measuring 14 cm² and 0.3 cm thick, with holes spaced 0.5 cm away and arranged in rows and columns. Each column was separately filled with 0.315 cm diameter metal spheres to acquire panoramic radiographs using the Orthopantomograph OP 100 unit. The customized phantom was placed on the mental support of the device, with its top surface kept parallel to the horizontal plane, and was radiographed at three different heights from the horizontal plane, i.e., the orbital, occlusal and mandibular symphysis levels. The images of the spheres were measured using a digital caliper to locate the image layer. The recorded data were analyzed statistically by the Student'-t test, ANOVA and Tukey' test (?=0.05). When the image size of spheres in horizontal and vertical axes were compared, statistically significant differences (p<0.05) were observed in all areas, portions of the image layer and heights of horizontal plane evaluated. In the middle portion of the image layer, differences in the image size of spheres were observed only along the horizontal axis (p<0.05), whereas no differences were observed along the vertical axis (p>0.05). The methodology used in this determined the precise size, shape and position of the image layer and differences in magnification were observed in both the horizontal and vertical axes.
authors.affiliation: Department of Oral Diagnosis, Piracicaba Dental School, University of Campinas, Piracicaba, SP, Brazil. danibrait@fop.unicamp.br
authors.forename: Daniela Brait Silva
authors.initials: DB
authors.lastname: Ladeira
authors.forename: Adriana Dibo da
authors.initials: AD
authors.lastname: Cruz
authors.forename: Solange Maria de
authors.initials: SM
authors.lastname: Almeida
authors.forename: Frab Norberto
authors.initials: FN
authors.lastname: Bóscolo
mesh_terms: D004867:Equipment Design; D057918:Fiducial Markers; D006801:Humans; D008334:Mandible / Q000000981:diagnostic imaging; D009915:Orbit / Q000000981:diagnostic imaging; D019047:Phantoms, Imaging; D011856:Radiographic Image Enhancement / Q000379:methods*; D011858:Radiographic Magnification; D011862:Radiography, Panoramic / Q000379:methods*; D014070:Tooth / Q000000981:diagnostic imaging