Ultrasonography as an additional tool to localize impacted canines

Canine impaction is a common dental anomaly that requires a multidisciplinary approach, from diagnosis to treatment. The regular two-dimensional (2D) radiographs are able to visualize if the tooth is impacted, but unable to specifically localize it, and determine if there are any root resorptions associated to it. The cone-beam computed tomography (CBCT) is able to three-dimensionally determine its location, aiding to the diagnosis and treatment plan. The major disadvantage is the amount of radiation that is added to the patient and can be even more significant in pediatric patients. The intra-oral ultrasound (io-US) is a new non-invasive and non-radiating real-time chairside imaging method that has the potential to aid in locating the impacted tooth. This paper presents 4 cases that required a CBCT for the location and treatment planning of impacted maxillary canines and were also scanned with intra-oral ultrasound. The images were then compared to the CBCT exam for validation of the new method. Through these cases, we highlight the capability of the io-US to locate the impacted canines. Other advantages of io-US might include evaluation of soft tissue thickness and vasculature that are important for surgical planning and execution.