Evolution of Assessment of Impacted Maxillary Canines from Plain Radiographs to Cone Beam Computed Tomography

Background: For a long time, radiographic assessment of impacted canines has been routinely carried out through plain film radiographs. However, plain radiographs tend to render distorted images of the impacted teeth due to an inherent magnification problem and they do not allow accurate assessment and positioning of overlapping structures. The emergence of cone beam computed tomography (CBCT) for three-dimensional imaging of the craniofacial region has revolutionized the radiographic assessment of impacted canines at a fraction of the radiation exposure associated with multi-slice computed tomography (CT). Methods: This article aims to review the available literature regarding the value of added information gained from CBCT on the examination and management of impacted upper canines. Results: It was concluded that CBCT is a useful imaging technique which is proven to be superior to plain radiographs in accurate localization of impacted upper canines and assessment of root resorption of adjacent teeth. Assessment of impacted upper canines through CBCT may alter the treatment planning and management of the case when compared to plain radiographs. CBCT may offer radiographic confirmation of sites of ankylosis affecting the impacted canine, however, it may produce false positive results. Conclusion: Although CBCT may cause more radiation exposure to the patient when compared to conventional radiographs, it is justified to be used in the assessment of impacted canines by a number of organizations concerned with limiting the use of ionizing radiation in dentistry, providing the field of view is restricted to the upper jaw only to reduce the amount of radiation exposure.