Development of 3D radiography for tooth and its supported structures

Research Project

Project/Area Number	11671880
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Single-year Grants
Section	一般
Research Field	病態科学系歯学(含放射線系歯学)
Research Institution	Showa University
Principal Investigator	ARAKI Kazuyuki Showa University School of Dentistry, Associate Professor, 歯学部, 助教授 (50184271)
Co-Investigator(Kenkyū-buntansha)	YAMAMOTO Mika Showa University School of Dentistry, Instructor, 歯学部, 助手 (30276604) MATSUDA Yukiko Showa University School of Dentistry, Instructor, 歯学部, 助手 (50266178) HARATA Yasuo Showa University School of Dentistry, Associate Professor, 歯学部, 助教授 (30119250) OKANO Tomohiro Showa University School of Dentistry, Professor, 歯学部, 教授 (20124688)
Project Period (FY)	1999 – 2000
Project Status	Completed (Fiscal Year 2000)
Budget Amount *help	¥3,500,000 (Direct Cost: ¥3,500,000) Fiscal Year 2000: ¥900,000 (Direct Cost: ¥900,000) Fiscal Year 1999: ¥2,600,000 (Direct Cost: ¥2,600,000)
Keywords	Digital radiography / Three dimensional / Tomography / Tomosynthesis / Intraoral radiography / Tooth / Periodontal tissue / Jaw
Research Abstract	Tuned-aperture computed tomography (TACT) is a new three dimentional radiographic method. We now are developing a TACT system adapted specifically to accommodate a panoramic projection architecture (Ortho TACT) wherein the x-ray source rotates in a single arc around the patient's head. The x-ray source and projection system were provided by an Orthopantomograph, OP-100. It was modified to accept a digital intra-oral CCD sensor. We studied its conditions which required for and accuracy for diagnosing dent-alveolar lesions. The experiments were consisted of two parts those were evaluation of slice thickness and diagnosing ability for periodontal bone resorption and temporomandibular joint (TMJ) bone changes. The angular disparity influenced slice thickness of Ortho TACT.For disparities greater than 20 degrees, slice thickness was estimated to be less than 1 mm. We therefore conclude that under these conditions angular disparities of 20 degrees or more may provide enough depth resolution to facilitate diagnosis of a large variety of common dental disorders. In case of diagnosis for periodontal bone resorption, OrthoTACT system is better performance than conventional intraoral bi-secting radiography. And in TMJ bone changes is considered to be depicted good quality. Total radiation dose for OrthoTACT system are almost same as that for intraoral radiography. In conclusion, OrthoTACT system is better three-dimensional radiographic methods for dent-alveolar lesions.