Regional odontodysplasia of the deciduous and permanent teeth associated with eruption disorders: A case report.

Regional odontodysplasia (RO) is an unusual, non-hereditary anomaly of the dental hard tissues with characteristic clinical, radiographic and histological findings. Clinically, RO affects the primary and permanent dentition in the maxilla and mandible or both jaws. Radiographically, there is a lack of contrast between the enamel dentin, both of which are less radiopaque than unaffected counterparts. Additionally, enamel and dentin layers are thin, giving the teeth a "ghost-like" appearance. Histologically, areas of hypocalcified enamel are visible and enamel prisms appear irregular in direction. Coronal dentin is fibrous, consisting of clefts and a reduced number of dentinal tubules; radicular dentin is generally more normal in structure and calcification. The RO etiology is uncertain; numerous factors have been suggested and considered as local trauma, irradiation, hypophosphatasia, hypocalcemia, hyperpyrexia. The treatment of RO has given rise to controversy. These cases require a continuous and multidisciplinary approach. Most clinicians advocate extracting the affected teeth as soon as possible and inserting a prosthetic replacement. Other clinicians prefer restorative procedures, if possible, to protect the affected erupted teeth. A case of RO in an 8 year-old male whose chief complaint was the absence of eruption of permanent teeth is presented. Clinical, radiographic and histological findings are described.