Mineralization differences between human deciduous and permanent enamel measured by quantitative microradiography.

The mineralization levels of erupted buccal enamel from 24 deciduous teeth were compared to those of 28 permanent teeth. Sections were prepared in a defined plane using a lapping machine which gave plano-parallel sections. Mineralization levels were recorded by quantitative microradiography at 25 equivalent anatomical sites in each section. Deciduous incisors and canines were compared with their homologous successors: overall mineralization levels were lower in the deciduous dentition, with no significant differences being found close to the amelo-dentinal junction, but highly significant differences being found in the outermost sites. Deciduous molars were compared with premolars, and were also relatively less mineralized. However, deciduous molars did not show the consistent diminishing occlusocervical gradient observed in all other tooth types tested; on the contrary, they showed a cervical reversal with higher values than permanent premolar enamel. These results confirm the generally lower mineral levels in deciduous enamel, and provide quantitative information on site-specific mineralization levels.