Maturation in developing permanent porcine enamel.

Mineral content per tissue volume was investigated in developing permanent porcine enamel and contrasted with weight-related data. Levels of mineralization were correlated directly with the histological appearance of the overlying enamel organ. Magnesium concentrations were measured at different stages of enamel development. Mineral levels rose from approximately 30% per volume of tissue during the secretory stage to approximately 60% in mature tissue. This is much lower than final mineral levels in enamel of other species. Enamel containing low mineral levels was adjacent to tall secretory ameloblasts which had reduced in height by approximately 50% at a point corresponding to the beginning of the maturation stage. Magnesium concentrations remained relatively constant throughout the secretory stage, at 0.2% Mg by weight. These rose by 3-4 times in the enamel of the maturation stage. The low levels of mineralization in the mature porcine enamel did not appear to be due to enamel pathology, and the possibility of porcine teeth erupting in an immature, partially porous condition is discussed.