High-resolution X-ray microdiffraction analysis of natural teeth

Abstract

The main component of natural teeth was determined many years ago as calcium phosphate, mostly in the form of hydroxyapatite with different crystallites. In the past, the method used in tooth crystal investigation has been mainly powder X-ray diffraction analysis, but this method has its drawbacks, i.e. the destruction of the natural tooth structure and the difficulty in examining the preferred orientation in different layers of the tooth. During the last century, microzone X-ray diffraction on the tooth surface was carried out, but, as the technology was less sophisticated, the results obtained were not very detailed. The newly developed microdiffraction equipment permits analysis of the microzone of teeth in situ. To test this new microdiffraction equipment, microdiffraction analysis of one natural healthy deciduous molar tooth and one carious deciduous molar tooth has been performed, using a Bruker D8 instrument. Phase analysis of the two teeth was performed; the crystal size at six test points in the natural healthy tooth was calculated by reflection (211), and the crystal preferred orientation of reflection (300) and reflection (002) at six test points in the natural healthy tooth were compared. The results showed that the tooth was a kind of biological mixed crystal composed of several crystal phases, the main crystal phase being hydroxyapatite. The crystal size grew larger going from the dentin to the enamel. The crystal preferred orientation mainly existed in the enamel, especially in the reflection (002). From our experiment, layer orientation and continuous crystal variations in teeth could be conveniently studied using fast online measurements by high-resolution X-ray microdiffraction equipment.

Structural and Dielectrical Properties of Sterilized Human Teeth

“…Therefore, the structure of the enamel is more senestive to γ-radiation than dentin. Similar results were previously reported in the literatures (Xue et al, 2008;Vieira et al, 2003).…”

Biomimetic Remineralization of Human Enamel in the Presence of Polyamidoamine Dendrimers in vitro

“…6 ). The results revealed that the average crystal sizes and preferential orientation of the biomimetic coating were almost the same as those of the intact enamel [Xue et al, 2008]. …”

Calcium orthophosphates (CaPO 4 ): Occurrence and properties

“…Similar to bones, the inorganic part of teeth also consist of biological apatite (Xue et al 2008). The stability of the mineral composition of teeth also has a very long history: namely, CaPO 4 were found in fossil fish teeth (Gaft et al 1996).…”