| Craniofacial malformations have been described in a population of individuals who were exposed to isotretinoin (13-cis retinoic acid, AccutaneRTM ) in utero. Among the unusual features of the primary dentition observed in this unique population of individuals was yellow-brown, gray, and purple staining of the teeth without any evidence of caries or obvious enamel defects. The discoloration associated with these teeth was localized histologically in paraffin embedded sections. Hematoxylin and eosin stained sections of the dentin were prepared and areas of deficient calcification with globular zones of mineralization (calscospherites), reparative dentin, and incremental growth lines were identified. Scanning electron microscopic (SEM) observations showed the presence of ultrastructural. defects (hypoplastic areas, microcavities and marked decussations) throughout the examined specimens. Energy dispersive spectroscopy (EDS) analyses conducted on these specimens recorded a significant reduction on calcium and phosphorus levels. Together with the whole tooth radiographs, these analyses provided comprehensive means for identifying structural defects resulting from the general or localized abnormalities of mineral deposition. By analyzing these primary teeth, we obtained information relative to alterations observed grossly in these teeth. In addition, the findings helped in assessing the usefulness of primary teeth as biomonitors of environmental influences. |
