Elements Of Hydroxyapatite Research Articles

Production and Evaluation of Hydroxyapatite (HAp) Properties of Broiler’s Composite Bone (BCB) Waste at Different Sintering Temperatures

Bone is one of the perishable livestock wastes, so serious attention is needed. The wastes are produced by Poultry Slaughterhouse (PSh) primarily in the process of separating meat from bone to produce boneless products. The main constituent of bone is the crystals Ca and P, which are the major elements of Hydroxyapatite (HAp). The purpose of this study was to produce HAp from the Broiler’s Composite Bone (BCB) waste as well as to evaluate the properties of BCB at different sintering temperatures. HAp was produced through 3 stages, i.e., calcination, precipitation and sintering. The calcination was carried out at 1000°C for 5 h and the resultant was evaluated by X-Ray Diffraction (XRD) and followed by precipitation with HPO4 0.3 M. The next stage was sintering process, using 6 level temperatures of 550°C, 600°C, 650°C, 700°C, 750°C, 800° and followed by XRD analysis. The results showed that calcination at 1000°C for 5 h demonstrated the efficiency of 41.99%. The intensity peak of calcination of the BCB was found at 2θ: 32.5250°, 19.7200° and 21.1200° (before calcination) and 32.5187°, 33.5626° and 33.0000° (after calcination). Sintering condition demonstrated significant effects on HAp yield. We also found that sintering process at 700°C (97.2%) was the most optimum temperature to produce HAp from BCB.

Preparation and Characterization of Biological Hydroxyapatite (HAp) Obtained from Tilapia Fish Bone

Hydroxyapatite, (HAp), Ca10(PO4)6(OH)2, is recognised as biomaterial that widely used for orthopedics due to its similar to the inorganic component of human bone and enamel .The elements of HAp are primarily calcium and phosphorous, with a stoichiometric calcium to phosphorous ratio of 1.67 capable of promoting bone growth. Enormous amounts of by-product wastes from fishery factory lead to generating an undesirable environmental impact. Thus, this study was conducted to obtain biological natural HAp extracted from tilapia fish bones from fishery factory. Therefore, fish bone can be as cheap resource to produce HAp and crucial contributions in medical application. The fish bones of tilapia were boiled at 100°C to remove adhere meat and other impurities. Later, were milled for 1 h to form fine powder. The powder was calcined at temperature of 800° C and 1000° C for 3h respectively. The XRD result revealed the presence derived HAp and coherent with Joint Committee on Powder Diffraction Powder Standard data and the Thermo Gravimetric Analysis was carried out to show the thermal stability of the HAp powder. SEM results shown hexagonal particle sHApe obtained from HAp powder. The findings present a promising future regarded on producing high added value product such as hydroxyapatite (Ca/P ratio 1.757) from fishery wastes beneficial to medical application.

Structural and Chemical Analysis of Crystal Enamel Nucleation

AbstractThe aim of the present study is to obtain structural and chemical information about nucleation and growth of dental enamel as a function of location in secretory mouse foetus enamel. Then enamel tissues were obtained from 19-days-mouse foetus. TEM images show that enamel crystallites had the well-documented thin ribbons, or needles. They were found in the outermost zone in the vicinity of ameloblasts. Chemical analysis by EDS showed that, besides the elements of hydroxyapatite, Na, Cl, Al and Mg are presents from the beginning of enamel mineralization. All of these elements will play an important role on the physics and chemical properties in mature enamel.

Morphological study of the teeth of Ambystoma maculatum, Salamandra salamandra and Aneides lugubris: fine structure and chemistry of enamel.

The functional teeth of adult salamander (Caudata): Ambystoma maculatum, Salamandra salamandra and Aneides lugubris were prepared for transmission electron microscopy and electron microprobe analysis of the elements and trace elements of the enamel layer. The arrangement of enamel crystals in these species is variable. The outer part of the enamel layer in which hydroxyapatite elements (Ca, P) and trace elements (e.g., F, Fe, Mg) are concentrated, is most mineralized. The concentration of trace elements are arrangement of crystals in the enamel layer differed in these species, may be related to the pattern of mineralization of enamel.

Morphology of the teeth of adult caudata and apoda: Fine structure and chemistry of enamel.

Representative functional teeth from Cryptobranchus alleghaniensis (Cryptobranchidae), Amphiuma means (Amphiumidae), Dicamptodon ensatus (Dicamptodontidae), Necturus maculosus (Proteidae), and Dermophis sp. (Costa Rica) (Caeciliidae) were prepared for transmission electron microscope and electron microprobe analysis of the trace elements of the enamel layer. The enamel layer of these species is very thin and the arrangement of enamel crystals variable. In particular, the outer part of the enamel layer in which hydroxyapatite elements (Ca, P) and trace elements (e.g., F, Fe, Mg) are concentrated, is most heavily mineralized. The concentrations and alignment of crystals in the outer and inner parts of the enamel layer differ among these species. The presence of collagen fibers in the inner part of the enamel layer of Cryptobranchus and Dermophis indicates that it is enameloid rather than true enamel. The presence of trace elements may be related to the pattern of mineralization of enamel or enameloid, as suggested for tetra-odontiform fishes by Suga et al. (J. Dent. Res. 68:1115–1123, 1989). © 1992 Wiley-Liss, Inc.