Comparison between the alpha angle of the maxillary impacted canines on panoramic radiographs and cone beam computed tomography

Abstract

There is a paucity of studies that make use of the alpha angle as a diagnostic tool to assist with the interceptive treatment, prognosis, treatment duration and surgical outcome of possible maxillary canine impaction in orthodontics. While the literature is replete with studies that utilise the sector method, the alpha angle is an alternative approach to assess the possible eruptive outcome of the unerupted canine. It has been reported that if the alpha angle is greater than 25°, there is the possibility of external root resorption. However, if the alpha angle is more than 31°, the prospect of canine eruption decreases even if the deciduous canine is extracted as an interceptive measure. The dental pantomograph has historically been used to predict canine eruption or possible impaction. The use of this method, however, is wrought with limitations. These limitations include magnification, distortion and blurred images. The use of cone-beam computed tomography has been advocated as a means to overcome these limitations.