3D CT imaging in orthodontics: Adding a new dimension to diagnosis and treatment planning

The use of lateral cephalometric radiographs forms an important diagnostic tool in orthodontic treatment as well as orthognathic surgery. However, their 2 dimensional nature presents an inherent limitation to the clinician, as the human body is 3 dimensional. In addition, a significant amount of radiographic projection error further limits their accuracy. Three-dimensional imaging of the human body via computed tomography has been available to the field of medicine for the last 30 years. However, the significant amount of radiation exposure associated with this technology, precluded its widespread use in dentistry. With the development of Cone Beam Computed Tomography, there has been a drastic reduction in radiation exposure to the patient, which allows its use for safely obtaining 3 dimensional images of the craniofacial structures. This should allow the clinician to visualize the hard and soft tissues of the craniofacial region from multiple perspectives, which could have far-reaching implications for treatment planning in orthodontics and orthognathic surgery. This paper shall discuss in detail the principles of the Cone Beam CT, and its applications in the field of orthodontics.