Hungarian Radiology

[Digital volume tomography - The use of cone beam CT in dentistry, oral and maxillofacial surgery]

PLACHTOVICS Márk

DECEMBER 21, 2009

Hungarian Radiology - 2009;83(04)

[Oral and maxillofacial radiology is a subspecialty with its own field of indication. The goal is to achieve proper diagnostic image quality with the minimal amount of harmful radiation. The most common acquisition techniques are the intraoral radiograph and the panoramic radiograph which result in an overview picture of the whole dental status of the patient or the full mouth survey with the higher doses of radiation indicated for periodontological treatment. The next level is the supplementary radiograph such as occlusal radiograph, transversal tomography (some panoramic radiographs have this option), lateral cephalometric projection, submentovertex view or Waters projection, etc. More over cone beam CT acquisition or digital volume tomography as is called. In case of some described special indications CT, MRI or sometimes US acquisition can be made. In the field of three dimensional radio-diagnostics, the CT has a superior place with well-known advantages for everybody, and the usage has been limited only by the high radiation dose. The main point of the acquisition is the image quality. The load of radiation only makes the field of indication narrow. In every day practice - because of the higher radiation load of each high quality CT - the pictures passing to the doctor are preferred to take with lower resolution and wider slices although the diagnostic value of this never reaches the wanted level. This is why this new acquisition system also mentioned in the title would be better known. This system works with reasonable low radiation coupling with the possibilities of the high fidelity 3D imaging focusing on the bony structures of the head and neck region. The purpose of this article is to give a comprehensive introduction to this method in use for more than a decade. From 2006 in Hungary we also have the option to use the technology.]

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