HISTOPATHOLOGIC IMMUNOHISTOCHEMICAL AND ULTRASTRUCTURAL COMPARISON OF A PATIENT WITH REGIONAL ODONTODYSPLASIA.

Background Regional odontodysplasia (RO) is a rare dental abnormality that usually affects a quadrant of both primary and secondary dentition, most often affecting the maxilla. This condition affects the hard tissues of the tooth and the affected teeth are described as “ghost teeth.” Objective To compare histopathologic characteristics, immunohistochemical expression, and ultrastructural features of the teeth from a Chilean patient affected by RO. Methods In the present study we included a patient who signed informed consent and agreed to donate exfoliated deciduous teeth. This study analyzed 3 teeth from this patient with RO and 7 normal teeth. These samples were analyzed by a ground sections technique in optical microscopy and polarized light microscopy, immunohistochemistry with anti-amelogenin antibody and anti-dentin sialophosphoprotein antibody, and scanning electron microscopy (SEM). Results On histopathologic analysis, RO-affected teeth presented thin enamel with a wavy surface, and dentin presented smaller thickness with abundant interglobular dentin. Immunohistochemical expression showed remanent tooth enamel matrix marked positive for amelogenin, and the control teeth lost the enamel matrix post decalcification. SEM analysis showed dentinal tubules with wide variation of diameters and enamel with disordered prisms, and the control teeth presented ordered tubules and prisms. Conclusions The histopathologic, immunohistochemical, and SEM study showed alterations in both enamel and dentin of the teeth affected by RO.