Teeth, elements

CavaUio M. L., et al. (2001) Human teeth elemental profiles measured by synchrotron x-ray fluorescence dietary habits and environmental influence. X-Ray Spectrometry 30, 190-193. 

Samsahl and Soremark (810,811), Lundberg and Soremark (571) and Soremark and Lundberg (886,887) and Soremark and Samsahl (888,889) have made extensive analyses of the elements in the enamel, dentine, and calculus of human teeth. Elemental species, such as, Na, P, Cl, Ca, Mn, Zn, Br, Sr, W, Au, Cu, Cr, Ag, Fe, Co, Rb, Hg, Sb, Cs, Ba, and Pt, were determined in these investigations. Many of the species were in submicrogram concentrations, and, in some instances, it was possible to complete these determinations by a nondestructive technique of analysis. 

Calcium is a metallic element, fifth in abundance in the earth s crust, of which if forms more than 3%. It is an essential constituent of leaves, bones, teeth, and shells. Never found in nature uncombined, it occurs abundantly as limestone, gypsum, and fluorite. Apatite is the fluorophosphate or chlorophosphate of calcium. 

Phosphorus. Eighty-five percent of the phosphoms, the second most abundant element in the human body, is located in bones and teeth (24,35). Whereas there is constant exchange of calcium and phosphoms between bones and blood, there is very Httle turnover in teeth (25). The Ca P ratio in bones is constant at about 2 1. Every tissue and cell contains phosphoms, generally as a salt or ester of mono-, di-, or tribasic phosphoric acid, as phosphoHpids, or as phosphorylated sugars (24). Phosphoms is involved in a large number and wide variety of metaboHc functions. Examples are carbohydrate metaboHsm (36,37), adenosine triphosphate (ATP) from fatty acid metaboHsm (38), and oxidative phosphorylation (36,39). Common food sources rich in phosphoms are Hsted in Table 5 (see also Phosphorus compounds). 

Fig. 4. Typical design elements foi wet deagglomeiation in low viscosity systems (a) a high, ipm lotoi (shown below its normal position within stator) produces turbulence and cavitation as blades pass each other (b) a rotating disk creates a deep vortex to rapidly refresh the surface, and up- and downtumed teeth at the edge cause impact, turbulence, and sometimes cavitation and (c) the clearance of a high rpm rotor can be reduced as the batch...

Gear elements with adequate hardness and surface finish have a greater resistance to initial scoring, a destructive phenomena found in meshing teeth. 

The elements of the roller rock bit are shown in Figure 4-137 [45]. Roller rock bits have three major components the cone cutter, the bearings and the bit body. The cutting elements are circumferential rows of teeth extending from... 

The elements of gear teeth common to all gears are tooth surface and profile, flank, top and bottom land, crown, root and pitch circle, gear center, line of centers, pitch point, line of action, line of contact, and point of contact. Figure 57.27 labels many of the common gear tooth elements. Figure 57.28 labels the common rack tooth elements. 

Figures 8.5 and 8.6. The liquid is carried round in the spaces between consecutive gear teeth and the outer casing of the pump, and the seal between the high and low pressure sides of the pump is formed as the gears come into mesh and the elements of fluid are squeezed out. Gear pumps are extensively used for both high-viscosity Newtonian liquids and non-Newtonian fluids. The lobe-pump (Figures 8.7 and 8.8) is similar, but the gear...

Alloys are metallic materials prepared by mixing two or more molten metals. They are used for many purposes, such as construction, and are central to the transportation and electronics industries. Some common alloys are listed in Table 5.5. In homogeneous alloys, atoms of the different elements are distributed uniformly. Examples include brass, bronze, and the coinage alloys. Heterogeneous alloys, such as tin-lead solder and the mercury amalgam sometimes used to fill teeth, consist of a mixture of crystalline phases with different compositions. 

Advanced Seminar volume reflects the greatly expanded awareness of the importance of diet reconstruction for understanding past human health and behavior. It also reflects the growing number of applications of stable isotope and trace element analyses of bones and teeth. 

The bones and teeth of humans and other vertebrate animals, for example, consist mainly of a composite material made up of an organic substance, collagen, and a biomineral, calcium carbonate phosphate (see Textboxes 32 and 61). The latter, which makes up about two-thirds of the total dry weight of bone, is composed of calcium phosphate containing between 4-6% calcite (composed of calcium carbonate) as well as small amounts of sodium, magnesium, fluorine, and other trace elements. The formula Ca HPChXPChMCChXOH) approximately represents its composition its crystal structure is akin to that... 

The isotopic distribution of lead (IDMS) in shed teeth from children has been shown to be useful in studies of the history of exposure to lead, including the definition of the source of the exposure, e.g., mine dust vs. food (Gulson and Wilson 1994), so IDMS certainly has important applicability, if not for routine determinations. ICP/MS, however, is easier, more sensitive, allows for multi-element analysis, and provides isotopic data. 

Phosphorus compounds occur widely in nature, with some of the most common forms being phosphate rocks and minerals, bones, and teeth. Phosphate minerals include calcium phosphate, Ca3(P04)2 apatite, Ca5(P04)30H fluoroapatite, Ca5(P04)3F and chloroapatite, Ca5(P04)3Cl. Elemental phosphorus was first obtained by H. Brand, and its name is derived from two Greek words meaning "light" and "I bear" because of the phosphorescence of white phosphorus due to slow oxidation. 

Open vessel digestion (HN03) for bones, teeth, hair, and soil This is a standard preparation for most organic samples. In the case of soils, nitric acid will not fully dissolve all of the sample, but this method is sufficient to examine the total available elements. 

Lee, K. M., Appleton, J., Cooke, M., Keenan, F., and Sawicka-Kapusta, K. (1999). Use of laser ablation inductively coupled plasma mass spectrometry to provide element versus time profiles in teeth. Analytica Chimica Acta 395 179-185. 

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