Inorganic components of the peritubular dentin in young human permanent teeth.

Abstract

Six premolar teeth, from patients aged11 to 15 years, were used in a study of peritubular and intertubular dentin in the crown and root. Anelectron microprobe with an associated scanning electron microscope was used to determine simultaneously the concentrations, in weight %, of calcium, phosphorus and magnesium, using a beam size of approximately 0.25 μm diameter. Coronal peritubular dentin was hypermineralized (total of Ca: P and Mg) by up to 9% by weight though usually this was between 2 and 4 %. Radical peritubular dentin was either hypo- or isomineralized in these young teeth when compared to the intertubular dentin. In most teeth the coronal dentin was more highly mineralized than the radicular dentin in both peritubular and intertubular area. Analysis of the data showed that there was a significantly greater variability of calcification in the peritubular dentin. These results are discussed particularly in relation to the microradiographic data which are available on dentin.