Chemical evidence of two separate apatite phases in human enamel

Wöltgens, J.H.M.; Vingerling, P. A.; Witjes, F.

doi:10.1016/0003-9969(80)90011-4

Cited by 8 publications

(3 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It seems that the Ca/P ratio of the enamel might be influenced by the nutritional regime (or diet) that the subject has during the pre-eruptive development of a tooth (Sobel & Hanok, 1958) and that coincides with a change in the PO4/CO 3 ratio of the serum (Woltgens, 1983). This probably influences the metabolic state of the mineralizing dentine cells (ameloblasts and odontoblasts) during enamel formation which leads to deposition of two discrete calcium salts with low or high CO 2-content (Boyde, 1979) that in humans have Ca/P ratios of 1.62 and 1.85 respectively (Woltgens, Vingerling & Witjes, 1980). On the other hand, inorganic and organic ions can condition the growth and the nature of both the enamel grain and the grain boundaries (Driessens, 1983).…”

Section: Resultsmentioning

confidence: 99%

Microstructural features of synthetic ceramized chlorapatite in comparison with human enamel crystals

Krajewski¹,

Ravaglioli²,

Wen³

et al. 1992

J Appl Cryst

View full text Add to dashboard Cite

Microstructural features of a series of synthetic calcium chlorapatitic ceramics are characterized and reported in this paper and compared with those gained by the identical analytical procedures on human enamel, which is constituted of hydroxyapatite. Some interesting differences are shown, particularly in the compounds with the highest levels of chlorine. Such differences concern the aggregation arrangement of the materials, particularly in relation to local distorsion in crystal lattice, grain shape, grain size, grain orientation and grain boundaries. The radiation damage introduced by the analyses and the intrinsic structural defects are different for chlorinated apatites and human enamel, showing that the ceramized synthetic chlorapatite has fewer structural defects and clearer grain boundaries than human enamel.

show abstract

Section: Resultsmentioning

confidence: 99%

Microstructural features of synthetic ceramized chlorapatite in comparison with human enamel crystals

Krajewski¹,

Ravaglioli²,

Wen³

et al. 1992

J Appl Cryst

View full text Add to dashboard Cite

show abstract

“…This is compatible with the findings for caries susceptibility of enamel as a func tion of depth [Theuns et al, 1982] as men tioned in the Introduction and also with the fact that Mg, Na and CO3 are lost pref erentially during carious lesion formation [Little, 1961;Little and Posen en Singer, 1962;Johansen, 1965;Hallsworth et al, 1972Hallsworth et al, , 1973, Due to the still relatively large size of the excited volume the variations in the Na and Mg content with spot position as found in the present study are probably a lower estimate of the real variations. That larger variations probably occur is indi cated by Woltgens et al [1980], These au thors sampled deeper layers of human tooth enamel at the 10 ¿im level and ana lyzed for Ca and P content. They found a bimodal distribution of C a/P molar ratios with peaks at 1.62 and 1.85.…”

Section: Discussionmentioning

confidence: 99%

Variations in the Mineral Composition of Human Enamel on the Level of Cross-Striations and Striae of Retzius

et al. 1984

Self Cite

View full text Add to dashboard Cite

Point count analyses were made with the electron microprobe for Ca, Na and Mg in a vertical cross-section through the enamel of a freshly erupted human pre-molar in the approximal area. A low excitation energy was chosen to limit the size of the excited volume and to suppress the evaporation of Na. The Na content showed variations with a wavelength of 6 ± 1 μm, which equals the distance of cross-striations. The Mg content showed variations with a wavelength of 25 ± 4 μm which equals the distance of striae of Retzius, whereby these striae probably contain a higher Mg content. On the assumption that higher Na and/or Mg contents represent mineral with a higher solubility, the observed variations in mineral composition help to explain the fine structure of carious lesions as observed frequently by microscopy and microradiography.

show abstract

“…Due to geometric considerations, the Retzius lines must cross the prisms (Rimes, 198513, 1987). Their visibility has been attributed to an altered structure andlor composition of the enamel along the striae: hypomineralization (Gustafson, 1959;Boyde, 19701, hypermineralization (Gustafson, 19591, altered mineral composition (Woltgens et al, 1980;Driessens et al, 1984), altered organic composition (Ducroc and Proust, 1973), increased widthldensity of prism sheaths (Sognnaes, 1949;Jansen and Visser, 1950;Osborn, 1973), increased width of interprism (Gustafson, 19591, reduced width of prisms (Bergman and Engfeldt, 1954;Gustafson, 19591, and change in prism direction, either cervically (Gustafson, 1945;Gustafson, 1959;Hinrichsen and Engel, 1966;Gustafson and Gustafson, 1967;Helmcke and Schulz, 1968;Weber and Ashrafi, 0 1990 WILEY-LISS, INC. (Osborn, 1973;Weber and Ashrafi, 1979). It has also been pointed out that variations exist within the same Retzius line (Gustafson, 1959;Klinger et al, 1978).…”

mentioning

confidence: 97%

Structural characteristics of staircase‐type retzius lines in human dental enamel analyzed by scanning electron microscopy

Risnes

1990

Anat. Rec.

View full text Add to dashboard Cite

Based on a scanning electron microscopic (SEM) analysis of adjoining, acid-etched planes cut through human cervical enamel, the structural characteristics of staircase-type Retzius lines have been clarified. Structural features associated with this type of Retzius lines--such as cleftlike defects, decreased dimension of prisms, increased interprism, club-shaped appearance of prisms, oblique ridges, and triangular regions--have been incorporated into a unifying, three-dimensional model. A continuous discontinuity defect, involving both prisms and interprism, is a prominent feature of this type of Retzius lines. Prisms and interprism facing the deep aspect of the cleftlike defect show an enlarged, flat surface that encroaches on the cervically situated prisms being rebuilt from the same cleft. The initial part of a prism taking off from the cleft is of distorted shape. As the prism reaches the level of the interprism cleft, it abruptly regains its normal size and shape. The relationship between this type of Retzius lines and the carious process is discussed, and it is suggested that the discontinuity defect may retard the carious lesion due to a protective effect of its supposed organic content. The developmental events creating staircase-type Retzius lines are discussed, and it is suggested that Tomes' processes are constricted near their bases with a corresponding increase in interprismatic growth region. Tomes' processes will have to reshape plastically as they move out of the constricted pits, trailing the parent ameloblasts as they resume enamel production and move in the direction of the prisms.

show abstract

Chemical evidence of two separate apatite phases in human enamel

Cited by 8 publications

References 4 publications

Microstructural features of synthetic ceramized chlorapatite in comparison with human enamel crystals

Microstructural features of synthetic ceramized chlorapatite in comparison with human enamel crystals

Variations in the Mineral Composition of Human Enamel on the Level of Cross-Striations and Striae of Retzius

Structural characteristics of staircase‐type retzius lines in human dental enamel analyzed by scanning electron microscopy

Contact Info

Product

Resources

About