Diagnostic methods of<unk>  include the use of clinical examinations and x-ray. The feasibility of using cone beam computed tomography to diagnose ankylosed teeth is also explored and discussed in a recent research article. Examinations of teeth are carried out to identify typical features of ankylosis, these features include varying percussion sound with adjacent normal teeth and a lack of mobility. However, these examinations are not always reliable. Although a metal sound on examination of percussion is usually used to indicate the presence of ankylosis, it is found that only one-third of ankylosed teeth give a metal sound in percussion test. In addition, a lack of mobility is not a definitive sign of ankylosis as the<unk>  can still be mobile if less than 20% of root surface is ankylosed . A definitive diagnosis of ankylosis is believed to be given by checking the mobility of the targeted<unk>  after applying orthodontic force, an ankylosed<unk>  will show no mobility. In early detection of ankylosis, radiographic examination is not effective because it only produces 2-dimensional graphic. This means that the ankylosed site would not be apparent if it is not perpendicular<unk> e x-ray beam. Therefore, it is impossible to identify ankylosis in some areas using x-ray, for instance, buccal or lingual root surface. To overcome such difficulty, cone beam computerized tomography (CBCT) is adopted to provide a 3-dimensional image for better clinical inspection of ankylosis. In a recent research article, a retrospective cohort study was conducted where a wide range of teeth clinically diagnosed as ankylosed were collected and analyzed. The histological sections of each<unk>  obtained from the CBCT scan were then evaluated by two specialists blinded<unk> e details of the research to ensure the fairness and objectivity of the result. As a result, all histologically established ankylosed teeth were identified by both observers provided with the CBCT image but some false positive results were obtained. It is concluded that CBCT scan can be used as a feasible and effective diagnostic method when it comes<unk> e detection of<unk> . However, it is not recommended to treat CBCT image as the sole model in the identification of ankylosed teeth unless the false positive results are being eliminated. Ankylosis and primary fail of eruption (PFE) give similar symptoms, since in both cases a targeted<unk>  is positioned not vertically and unresponsive to orthodontic force applied. Therefore, ankylosis should be differentiated from primary fail of eruption. For an ankylosed molar, distal teeth can respond to orthodontic force normally and thus can be used as substitute if the ankylosed<unk>  is extracted. Surgical luxation is sometimes used to break the ankylosis bridge to restore occlusion. For a case of PFE, the targeted molar can only be treated by osteotomy to restore its occlusion.
Tooth ankylosis
Radial dysplasia
Metaphyseal dysplasia
Multiple epiphyseal dysplasia
Spinal stenosis
Carpal coalition
Fibrous ankylosis
Tarsal coalition