Rotational Panoramic Radiography Seung Hyun Heo Radiography v

Rotational Panoramic Radiography Seung - Hyun Heo

Radiography v IN Horizontal Dimension - Rotation center of the beam >> Serves as the functional focus. v IN Vertical Dimension - X-Ray Source >> Serves as the functional focus. : Just as a conventional radiographic projection.

Intra. Oral v. s. Extra. Oral v Extra. Oral Radiography - Panoramic Radiography , Tomography - Show the entire dentition and related structures on a single film. - The patient in a seated position, and other types require the patient to be in a standing position. - Regardless of the type of machine, Must follow the manufacture`s instructions carefully - Panoramic film are not as clear or as well defined as the images on Intra. Oral films - 구내 방사선 사진들에 비하여 촬영이 간단. 방사선 노출량이 적고, 개구제한이있는 환자에도 사용가능. 구내 방사선사진에 비하여 해상도가 떨어지며, 소구치부의 인접면 중첩현상이 있다. 확대율이 일정하지 않으며 기하학적 왜곡이 발생한다. v Panorama - “ an unobstructed view of a region in any direction” - The series of images are combined onto a single film, an overall view(panorama) of the maxilla and mandible is created.

Conventional CT vs Cone. Beam CT v Voxel(체적소)

Process of Image reconstruction.

Detector v 영상 증배관 및 CCD Sensor 사용방식. v 비결정실리콘(amorphous Silicon , a-Si)소자를 배열한 박막필름 트랜지스터 (thin-film transistors, TFTs)를 사용하는 flat-panel detector.

Focal trough : 상층 v 파노라마 방사선 사진 상에 구조물이 명확하게 나타나는 입체적 곡면. - An imaginary, 3 D curved area that is horseshoe shaped - When the jaws are positioned outside of this area, the images on the radiograph will appear blurred or indistinct.

Component of a panoramic unit v Panoramic x-ray tubehead

Component of a panoramic unit v Head Positioner - Align the patient`s teeth as accurately as possible. - Consist of a chin rest, notched bite-block, forehead rest, and lateral head supports or guides.