Diagnosis is mostly based on general examination and radiographs, and it should be taken when abnormality of the teeth is suspected as most of the affected teeth have normal clinical appearance. Differential diagnosis is very important to have a definitive diagnosis as some radiographic or histologic features of<unk>  may bear a resemblance to different disorders: *<unk> ogenesis imperfecta * Odontodysplasia * Calcinosis * Osteogenesis imperfecta * Ehlers–Danlos syndromes * Goldblatt syndrome * Schimke immuno-osseous<unk>  * Brachio-skeleto-genital syndrome. Type I: Radicular type Type I has been known as radicular<unk>  because the teeth have undeveloped root(s) with abnormal pulp tissue. Morphology and colour of the crown mostly appear normal, but occasionally teeth appear slightly amber coloured or bluish-brown shine in primary teeth with no or only immature root development. The teeth are mostly maligned and have higher risk of fracture. Radiographic feature In other words, affected primary teeth usually have abnormal shaped or shorter than normal roots. “Crescent/half-moon shaped” pulp chamber remnant in permanent teeth can be seen on x-rays. The roots may appear to be darker or radiolucent/pointy and short with apical constriction.<unk> e is laid down abnormally and causes excessive growth within the pulp chamber. This will reduce the pulp space and eventually cause incomplete and total pulp chamber obliteration in permanent teeth. Sometimes periapical pathology or cysts can be seen around the root apex. Most cases of DD associated with peri-apical radiolucency/ pathology have been diagnosed as radicular cysts, but some of them have been as diagnosed peri-apical grauloma instead. Type II: Coronal type Type II would mostly cause discolouration to the primary teeth. Affected teeth usually appear as brownish-blue, brown or yellow. Translucent “opalescence” is often one of the characteristics to describe teeth with DD-2. In some cases teeth might show slightly amber coloured but in most of the cases permanent teeth are unaffected and appear normal regardless of colour, shape and size. Dental X-rays are the key to diagnose<unk> , especially on permanent teeth. Abnormalities of the pulp chamber is the main characteristic to make a definitive diagnosis. In the primary teeth, coronal<unk>  may appear similar to<unk> ogenesis Imperfecta type II (DG-II) but if abnormalities features appear to be more pronounced in the permanent teeth, then consider changing the diagnosis to DGI-II instead of DD-2. Radiographic features In coronal type, teeth show normal roots containing enlarged pulp with abnormal extensions towards the roots, which is often described as “thistle tube” shaped on dental radiographs. As well as this, numerous pulp stones can be often found in the pulp chambers due to abnormal calcifications. In primary teeth, the pulp chamber is usually completely obliterated but in permanent teeth, the pulp may become partially obliterated after eruption. Histological features There are a few studies and proposals that were designed to explain the pathogenesis of DD but the main reason of the cause still remains unclear in the dental literature. Logan et al., suggested that dental papilla is the cause of abnormal root growth or development. They also proposed that calcification of multiple degenerative foci within the papillae reduce the growth and eventually leads to pulpal obliteration. Wesley et al., suggested that odontoblasts with abnormal function and/ or differentiation are mainly due to atypical interaction between odontoblasts and ameloblasts. Histopathologically, deeper layer of the teeth shows abnormal<unk> e tubular pattern with unstructured, unorganised, atubular areas with normal enamel appearance. Globular or small mass of rounded or irregular shape of atypical<unk> e is often seen in the pulp.
Dentin dysplasia
Exostosis
Enostosis
Heterotopic ossification
Hypercementosis
Cemento-osseous dysplasia
Hyperostosis
Tooth ankylosis