Morphology of dental enamel and dentine-enamel junction in osteogenesis imperfecta.

Abstract

The aim of this study was to examine the morphology of primary and permanent human enamel, and the dentine-enamel junction, in individuals with osteogenesis imperfecta (OI) type I, III and IV in undecalcified sections using polarized light microscopy, microradiography and scanning electron microscopy (SEM), and to relate the findings to the type of OI. Extracted or exfoliated teeth from 15 patients representing the OI types I, III and IV (12 primary teeth from seven patients, and 11 permanent teeth from eight patients). Ten primary and nine permanent teeth from normal healthy patients served as controls. The teeth were serially cut longitudinally in a bucco-lingual direction and contact microradiographs were made. The sections were examined in polarized light. Sections of primary and permanent teeth were examined by means of SEM. This study shows that the permanent enamel from patients with OI exhibits few structural changes. No relationships were found between enamel morphology and the types of OI (I, III, IV). Primary enamel appeared to be slightly more irregularly mineralized, especially in cases with the additional diagnosis dentinogenesis imperfecta. The major findings were deviations in association with the dentine-enamel junction, and locally a lower degree of mineralization. The mesodermal disease OI might also be manifested in ectodermal enamel, probably because of suboptimal mesenchymal-ectodermal interactions during amelogenesis.