J Meikai Dent Med 362, 153 160, 2007 153 X X X 0.5 mm 2mm X X 0.91.0 6.93 mm 6.93 mm 20 mm 9.5 10.4 30 mm 6.3 6.9 X Radiological Study for Implant Preoperative Diagnosis Geometric Accuracy of Panoramic Radiograph intheanteriorregion of the Mandible Hiroko KUROIWA Department of Oral Radiology, Matsumoto Dental University School of Dentistry Director : Prof Masaru SHIOJIMA Abstract : The purpose of this study is to evaluate the geometric accuracy of panoramic radiograph in the anterior region of the mandible for implant preoperative diagnosis. Variations of vertical/horizontal dimensions and magnifications of the panoramic images for the labial and lingual inclination of the mandible were examined. The experimental object in which steel balls 0.5 mm diameter at intervals of 2 mm were embedded, was radiographed with the panoramic X-ray unit. According to the experiments and calculations of the intervals and vertical/horizontal magnifications of the X-ray images, it was effective to evaluate the vertical dimension of the anterior of the mandible, and it did not much depend on the inclination of the mandible. When the image layer thickness is defined as 0.9 1.0 of the roundness, itwas 6.93 mm, which value is closer to the calculated value. When the image layer thickness is 6.93 mm, the maximum permissible angles of the inclination were 9.5 degrees on the labial side and 10.4 degrees on the lingual side of the object length 20 mm, 6.3 degrees on the labial side and 6.9 degrees on the lingual side of the object length 30 mm. Key words : implant preoperative diagnosis, the anterior region of the mandible, panoramic radiograph, geometric accuracy of image
154 36, 2007 1 2 3, 4 X CT X CT 5, 6 X 7, 8 X X 9 X 10 11 12 X X 1 30 mm60 mm 0.5 mm SUS 304 2mmISO 9001, JIS Z 9901 2.0 0.1 mm 5 399-0781 1780 15 Fig 1 a,illustration of experimental object. b,external view of experimental apparatus. c, Anexample of radiophotograph in this object. 040 26 Y 126 20 mm 5 XN 1530 mm 5 XF 15 Fig 1a Fig 1b 20 mm 30 mm 13 2 X AZ 3000 5 0 40 60 kvp 2mA 1 DR-P X Fig 1c 1 PJ 311 Stat Mate III SRS 2
155 Fig 2 Geometry for calculation of the image layer in panoramic radiography. Fig 2 McDavid 14, 15 X 0.5 mm 0.5 mm X ES-10000 G Scion ImageScion, Frederick, MD, USA Fig 3 Vertical intervals of the X-ray image of the steel balls in the labio-lingual inclination. 1 1 Fig 3 0 35 Fig 4 Fig 5 Fig 6 Fig 7 Y 26 10 Y26 Fig 4 Horizontal intervals of the X-ray image of the steel balls in thelabio-lingual inclina-tion. Fig 5 Vertical diameters in the X-ray images of the steel balls of the vertical array in the labio-lingual inclination.
156 36, 2007 Fig 6 Vertical diameters in the X-ray images of the steel balls of the horizontal array in the labio-lingual inclinationxf 15, XN 15 Fig 8 Horizontal diameters in the X-ray images of the steel balls of the horizontal array in the labio-lingual inclinationxf 15, XN 15 Fig 9 Vertical/horizontal magnification and roundness obtained from the calculation in the labio-lingual deviation. Fig 7 Horizontal diameters in the X-ray images of the steel balls of the vertical array in the labio-lingual inclination. Fig 8 XF 15 2 2 Fig 9 McDavid 14, 15 1 40 mm 0 mm 28 mm Fig 10 Fig 11 30 30 Fig 12 30 30 14 mm 15 mm
157 Fig 10 Vertical/horizontal magnification and roundness obtained fromthe experiment in the labio-lingual deviation. Fig 13 Comparison between calculation data and experimental data in the inclination of the +/ 30 degrees in the labio-lingual deviation. Fig 11 Vertical/horizontal magnification and roundness obtained from the calculation in the inclination of the +/ 30 degrees in the labio-lingual deviation. Fig 14 Horizontal magnification obtained from the various methods in the inclination of the +/ 30 degrees in the labiolingual deviation. Fig 13 30 30 Fig 14 Fig 12 Vertical/horizontal magnification and roundness obtained from the experiment in the inclination of the +/ 30 degrees in the labio-lingual deviation. X X
158 36, 2007 1 1 X 35 10 XN 15 XF 15 X L1-toMandibular Angle 16 95.08.0 92.28.0 X 2 2 2 McDavid 14, 15 30 30 Fig 11 14 mm 15 mm Fig 12 Fig 13 Fig 14 X X 3 X 17 Modulation Transfer FunctionMTF 18 2mm Tronje 19 McDavid 20 Welander 21 X X McDavid 14, 15 1 2 10.2 0.81.2 6.73 mm 6.43 mm 13.16 mm
159 Fig 15 Image layer thickness obtained from the roundness in the calculation in the labio-lingual deviation. Fig 17 Permissible inclination angles of the object when the image layer was defined as from 3.62 mm to 3.31 mm. Fig 16 Image layer thickness obtained from the roundness in the experiment in the labio-lingual deviation. 10.1 0.91.1 3.31 mm 3.14 mm 6.45 mm Fig 15 1.21 1.0 0.9 3.31 mm 3.62 mm 6.93 mm Fig 16 14, 17, 18 4 X X 6.93 mm 0.9 1 Fig 17 6.93 mm 3.31 mm 3.62 mm 20 mm 9.5 10.4 30 mm 6.3 6.9 X CT X X CT X 0.5 mm 2mm X
160 36, 2007 X 0.91.0 6.93 mm X 6.93 mm 20 mm 9.5 10.4 30 mm 6.3 6.9 1 62 18 7 48 19 5 In pp13 14, 2005 Garcia LT In pp21 31, 1989 In pp22 29, 2000 Beumer J and Lewis SGIn pp15 29, 1990 Ortho- CT 77, 17 23, 2003 CT CT 80, 5 9, 2006 X In 4 pp330 336, 2006 In pp91 99, 2005 Garcia LT In pp65 73, 1989 X DLP 13, 59 68, 2000 14, 423 428, 2001 X 34, 249 259, 1994 In 1 2 pp201 205, 1992 McDavid WD, Welander U, Kanerva H and Morris CR : Transfer function analysis in rotational panoramaic radiography. Acta Radiol Diag 24, 27 32, 1983 McDavid WD, Welander U, Kanerva H, Tronje G and Morris CR : Definitions of unsharpness and layer thickness in rotational panoramic radiography. Oral Surg Oral Med Oral Pathol 57, 96 101, 1984 Downs Northwestern 17, 1 6, 1990 26, 691 709, 1988 34194, 1994 Tronje G : Image distortion in rotational panoramic radiography. Dentomaxillofac Radiol Suppl 3, 4 18, 1982 McDavid WD, Tronje G, Welander U, Morris CR and Nummikoski P : Imaging characteristics of seven panoramic x-ray units. Dentomaxillofac Radiol Suppl 8, 29 43, 1985 Welander U, Tronje G and McDavid WD : Theory of rotational panoramic radiography. In : Panoramic radiology. Langland OE, Langlais RP, McDavid WD and DelBalso AM, eds, 2nd ed, Lea &Febiger, Philadelphia, pp38 75, 1989 2007 5 31 2007 6 27