The advent of three-dimensional (3D) imaging technology has caused a significant change in the diagnostic approach practiced in dentistry, and in particular, orthodontics. Although conventional imaging methods such as orthopantomography and lateral cephalometric and anteroposterior graphs provide sufficient information in mild to moderate orthodontic anomalies, 3D imaging can be a necessity in severe skeletal anomalies or tooth impactions. Computed tomography (CT) has been frequently used when detailed 3D imaging is necessary despite its relatively high cost, low vertical resolution, and high dose of radiation. In contrast to conventional CT application, the development of cone beam computed tomography (CBCT) technology has had important advantages over the conventional method, such as minimization of the radiation dose, image accuracy, rapid scan time, fewer image artifacts, chair-side image display, and real-time analysis. These advantages have provided dental practitioners the opportunity to benefit more frequently from 3D imaging by relatively diminishing radiation dose considerations, financial burden, and availability, in particular. Therefore, the aim of this review is to highlight the current understanding of CBCT practice in orthodontics and to summarize clinically relevant conditions.
Keywords: Cone beam computed tomography, orthodontics, 3D imaging
Orthodontics and Radiographic ImagingThe primary aim of orthodontic treatment, and in particular, dentofacial orthopedics, is the correction of malocclusions and facial discrepancies, which are related to dental and skeletal divergences. The treatment plan to achieve this aim is usually based on a patient's main complaint as well as the capabilities of orthodontics. Expected treatment outcomes have esthetic, psychosocial, and functional aspects. Differential diagnosis and treatment planning of such anomalies usually require detailed radiographic imaging of facial components. Conventional radiography and lateral cephalometric imaging, in particular, have formed the cornerstone of the diagnostic procedure for decades. 1 The limitations of such conventional techniques arising from the alteration of three-dimensional (3D) anatomy to two-dimensional images have been pronounced as one of the factors inducing treatment failure and relapse.2 These include magnification differences, geometric distortion, superimposition of anatomic structures, projective displacements of anatomic structures, rotational errors, and linear projective transformations.3 With the advent of computed tomography (CT), and more recently, cone beam computed tomography (CBCT), 3D imaging of the anatomy can be achieved, which enables the visualization of complex relations of adjacent tissues. 4 This has been enhanced with the development of computer software technology, which has enabled detailed assessment of these images for varying demands.