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  • articleNo Access

    ELEMENT ANALYSIS OF TEETH FROM CHILDREN WITH AND WITHOUT CYSTIC FIBROSIS BY PIXE-PIGE

    The objective of this research is to determine whether there is a difference in the Ca, P, Fe, F, Mg, and Sr concentrations in teeth from children with and without cystic fibrosis (CF) as a function of age, sex of the child, maternal smoking habit, maternal drinking habit, and fluoridation of water supply. The nuclear analytical methods used were Proton-Induced X-Ray Emission (PIXE) and Proton-Induced Gamma Emission (PIGE). The findings are: (1) the concentration of Mg is higher in the teeth of children with cystic fibrosis who took antibiotics other than tetracycline (CF+NT) than in non-cystic fibrosis (NCF) teeth for the “female” category; (2) P concentration is less in (CF+NT) teeth for the “age greater than ten” group; (3) Fe concentration is greater for females in the NCF group; (4) Ca and Fe concentrations are lower for CF than for NCF in the “mother smokes” group; (5) F and Sr concentrations for CF+NT are higher for the “mother drinks” group than for the “mother does not drink” group; (6) “mother smokes” shows a depletion of Ca and Fe compared to “mother does not smoke” for CF+NT. (7) “fluoridation of water supply” shows an increase in F, except for NCF teeth.

  • articleNo Access

    TRACE ELEMENT ANALYSIS OF TEETH FROM PRE-COLUMBIAN POPULATION GROUPS IN MÉXICO

    Human teeth from pre-Columbian and recent population groups have been analyzed by PIXE. Ancient teeth corresponding to children and adults were obtained from archaeological burials located in five geographic areas of Mexico. Inter-specific and inter-site differences in the trace element contents of enamel were compared in order to get some insight into differences in diet, environmental conditions, teeth health, disease state and post mortem alteration among the co-occurring populations. For permanent teeth from adults, small variations in trace element levels were found depending on the collection site or tooth health, but for deciduous teeth from children, the concentration of elements such as Mn, Fe and Sr varied considerably. In this work, the possible sources of variation are discussed.

  • articleNo Access

    NANOMECHANICAL BEHAVIOR OF HUMAN MOLARS SOAKED IN SLIGHT ACID SOLUTIONS

    This paper studied the mechanical and chemical properties of hydroxyl apatite (HA) crystal structure in the teeth when human molars were soaked in slight acid solution. First, we soaked the ground and polished molars respectively in the liquor of 30 wt.% H2CO3 and the liquor of 30 wt.% H2O2 for 10, 20, or 60 minutes. Next, we used a nanoindenter to measure the hardness and Young's modulus. Finally, we used a scanning electron microscope (SEM) coupled with energy dispersive spectroscopy (EDS) to analyze the variation of Ca, P and Na in teeth, a high resolution transmitting electron microscope (HRTEM) to observe the arrangement of crystallization phase of HA, and X-ray diffraction (XRD) to analyze the crystallinity of the hexagonal phase of HA. The results showed that the demineralization phenomenon of the calcium–phosphorous compound in teeth made the teeth reduce sharply in hardness and Young's modulus after they were soaked in the two slight acid solutions for 10 minutes, but the re-mineralization phenomenon made the hardness and Young's modulus ascend gradually when the time lasted longer. With the same period of time, the teeth soaked in H2CO3 were lower in the hardness and Young's modulus than that in H2O2.

  • articleNo Access

    Bioboard

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      INDIA – CSIR Completes First Ever Human Genome Sequencing in India.

      INDIA – India among Top 5 Government Funders of Neglected Diseases.

      INDIA – Doctors Use Stem Cells to Regrow Teeth in Children.

      INDIA – Delhi to Have First Govt-owned Liver Institute.

      JAPAN – Israel, Japan Unite For First Time to Study Brain, Stem Cells.

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      SINGAPORE – Scientists Discover Natural Compound in Palm Oil Kills Breast Cancer Cells.

      SINGAPORE – More than 200 Scientists Attend A*STAR Biomedical Sciences Symposium.

      SINGAPORE – Global Phase III Clinical Trial to Treat Head and Neck Cancer Begins.

      EUROPE – Stem Cell Treatment Helps Regain Eyesight.

    • articleNo Access

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