Mineral distribution in highly fluorotic and in normal teeth: A synchrotron microcomputer tomographic study

Abstract

A healthy and a fluorotic human molar tooth were studied by high-resolution synchrotron microcomputer tomography (SRlCT) and compared with respect to their structure and mineral distribution. The teeth were measured in their full size, i.e. without introducing segmentation or cutting artefacts. Enamel and dentin were clearly separated on the basis of their different X-ray absorption coefficient. No significant differences in the degree of mineralization were found between the healthy and the fluorotic tooth, except for a slightly rougher enamel surface of the fluorotic tooth.Key words: Teeth; enamel; dentin; mineral; fluorosis; microcomputer tomography; synchrotron radiation Ein gesunder und ein fluorotischer humaner Zahn wurden mittels hochauflösender Synchrotron-Mikrocomputertomographie (SRlCT) untersucht und hinsichtlich Struktur und Mineralverteilung verglichen. Die kompletten Zähne wurden vermessen, d. h. ohne Segmentierung oder Zerteilungsartefakte. Zahnschmelz (Enamel) und Dentin (Zahnbein) konnten klar durch ihren unterschiedlichen Röntgenabsorptionskoeffizienten unterschieden werden. Es wurden keine signifikanten Unterschiede im Grad der Mineralisation zwischen dem gesunden und dem fluorotischen Zahn gefunden, abgesehen von einer etwas höheren Rauigkeit der Schmelzoberfläche des fluorotischen Zahnes.

Early Childhood Caries: Epidemiology, Aetiology, and Prevention

“…This mechanism was thought to make teeth more resistant to acids and protect the enamel. However, only small amounts of fluorapatite can be detected [ 50 , 73 – 75 ]. Interestingly, fluorotic teeth with higher concentration of fluoride are even less resistant to acids than sound enamel [ 75 – 77 ].…”

Synchrotron X-ray Studies of the Structural and Functional Hierarchies in Mineralised Human Dental Enamel: A State-of-the-Art Review

“…An example of the internal output of this technique can be found in the investigation of chimpanzee and Neanderthal molars using the segmentation and extraction of the 3D structure of rods from the enamel surface to DEJ with a voxel size of 0.678 µm [ 451 ] ( Figure 8 a). This technique has also been used in several other fields of dentistry, to study endodontic post and apical sealers, with the analysis of defects with a pixel size of 5 µm [ 526 ]; to study fluorosis, with the analysis of X-ray absorption coefficient in comparison to a healthy tooth with a voxel size of 12.94 µm [ 484 ]; chemo-mechanical treatments for root canal fillings, with analysis of tissues and debris [ 371 ]; as well as cracks formed after root canal preparation, extraction, and cryopreservation [ 342 , 417 , 456 ]. Similarly, X-ray tomography was also used to investigate post-endodontic restorations, to assess the bonding of composite resin cement, and identified gaps and voids with a pixel size of 650 nm [ 344 , 345 ] ( Figure 8 a), as well as remineralisation [ 314 ].…”

Synchrotron microcomputer tomography for the non-destructive visualization of the fish skeleton

“…Synchrotron radiation sources have the advantage of fewer artefacts due to the monochromatic X‐radiation and also of the tunability of the X‐ray energy. The latter permits an easy adjustment for weakly or strongly absorbing samples, up to full‐size human teeth (Neues et al., 2009). The spatial resolution is comparable for synchrotron and laboratory instruments (Olejniczak et al., 2007).…”