Biomaterials.info - Resources for Engineers

Record 301 to 320

[The characteristics of biomaterials: HA, titanium, polytetrafluoroethylene, teflon fluorocarbonate, polyglactin 910, polypropylene]
Cozzolino, A., F. Maffettone, et al. (1993), Minerva Stomatol 42(9): 375-82.

[The characterization by Fourier-transform infrared vibration spectroscopy of mineral-based biomaterials commonly used in dentistry. 4]
Bottura, G., R. Mongiorgi, et al. (1995), Minerva Stomatol 44(1-2): 33-42.
Abstract: In this study the following biomaterials were analysed by means of Fourier transform infrared vibrational spectroscopy (FTIR); they are: reabsorbable Dac Blu, non reabsorbable Dac Blu, non reabsorbable atomized Dac Blu, non reabsorbable fine Dac Blu, reabsorbable Biocoral 450, Calcitite 2040-12, Orthogel, Apagen, BTF 65, Calcitite 4060-2 Osprogel, Bio-Oss, Biostite, Osprovit, Merck Hydroxyapatite. The analysis was performed with a Jasco 5300-FTIR. At 64 readings for spectrum with a 2 cm-1 resolution. By means of this method it has been possible to perform a structural study at a molecular level of the commercial products mentioned before. The analysis showed which of the samples examined had lost the apatite OH- group during production. It also allowed the identification of some of the hydroxyapatites examined as carbonate apatites. Finally, it allowed the identification and quantification of the organic substances in the examined products.

[The clinical applications of biomaterials]
Giudice, M., G. Colella, et al. (1993), Minerva Stomatol 42(9): 399-412.
Abstract: The more and more availability of new alloplastic materials in oral and maxillo-facial reconstructions causes the necessity of judging if the biomaterials satisfy the surgical needs. The authors re-examine the main chemical, physical and biological characteristics of following materials: hydroxylapatite, polytetrafluoroethylene, polyglactin 910, polyfluorocarbons, polypropylene and report their experiences.

[The deciduous tooth, an experimental model for the study of biomaterials]
Aldin, P., M. Goldberg, et al. (1987), J Biomater Dent 3(4): 269-72.

[The dependability and safety of biomaterials and medical devices]
Li, Q. (2005), Zhongguo Yi Liao Qi Xie Za Zhi 29(1): 46-9.
Abstract: This article describes emphatically the dependability, safety and their guarantee measures for biomaterials and medical devices.

[The developement of a new torque experiment device for biomaterials]
Li, H., Z. Zhen, et al. (1997), Sheng Wu Yi Xue Gong Cheng Xue Za Zhi 14(3): 255-6, 268.
Abstract: This paper introduces a biomaterial torque experiment apparatus which consists of AST486 computer, photodiode array, code device interface circuit, and magnetoelectric motional coil structure. According to experimental conditions, the computer sends out signal to the coil which under the magnetic field is activated to produce a series of desired torque and bring the sample to deflect. Angular displacement is measured by photodiode array and code device system. The whole system has good dynamics and high precision and could finish a series of torque experiment for biomaterials, and AST486 computer can automatically conduct signals analyzing and data processing.

[The effect of biomaterials and other industrial materials on the growth of several aerobic bacterial species in vitro]
Oehring, H., E. Beleites, et al. (1992), Zentralbl Hyg Umweltmed 192(5): 462-72.
Abstract: The article deals with interactions between bio-vitro-materials and bacteria species in vitro. The growth of S. aureus, Sc. salivarius, E. coli and Ps. aeruginosa in a salt solution with and without addition of biomaterials was examined until the day 60 in a static culture. By counting the cfu/ml and determination the relative change of germ capacity the results were compared. The data of such series obtained with working materials of similar chemical composition were collected and evaluated. We found, that Ps. aeruginosa was promoted in growth by all materials, especially those, which contained carbon. The same can be said about the last materials and E. coli. In contrast as well Ca- and P-containing as--free biomaterials reduced the numbers of germs. Changes of multiplying of S. aureus and Sc. salivarius seldom were observed. It ist apparent, that the biomaterials tested are not indifferent against a few germs, which may cause infections, but they promote the growth of a few species in vitro. This may favour an infection, if such materials should be implanted. It is proposed to test biomaterials microbiologically before clinical application. Materials with indifferent behavior or low anti-microbiological effect have to be favoured.

[The effect of biomaterials on cytochrome c]
Nagase, M., M. Chigira, et al. (1987), Nippon Seikeigeka Gakkai Zasshi 61(11): 1227-36.
Abstract: The adsorption of ferricytochrome c and ferrocytochrome c on biomaterials was studied by measuring the spectrum of samples assuming the molar extinction coefficients of the ferricytochrome c and ferrocytochrome c at 480 nm and 550 nm. Silica, alumina ceramic, zirconium ceramic, tricalcium phosphate ceramic, hydroxyapatite ceramic, unidirectional calcium phosphate glass-ceramic, bulk crystallized calcium phosphate glass-ceramic and bulk crystallized calcium phosphate glass-ceramic containing large amount of titanium were used as adsorbents. The adsorption of ferricytochrome c or ferrocytochrome c on silica essentially followed the Langumuir adsorption isotherm. Quantitative analysis showed that ferricytochrome c was adsorbed more and dissolved less than ferrocytochrome c on batch adsorption on silica. Total amounts of adsorbed and non-adsorbed ferricytochrome c increased significantly in batch adsorption of ferrocytochrome c on silica. From these experiments it appears that materials such as silica induce a transfer of electrons of cytochrome c.

[The experimental grounds and clinical application of domestic endoprosthesis "Esfil" for plasty of the abdominal wall]
Sukovatykh, B. S., A. I. Bezhin, et al. (2004), Vestn Khir Im I I Grek 163(6): 47-50.
Abstract: An investigation of physico-mechanical properties and a histological examination of meshed endoprostheses "Esfil" ("Lintex" St.Petersburg) and nets "Prolene" ("Ethicon") implanted into the abdominal wall of 66 Chinchilla rabbits was carried out under experimental conditions. The comparative experimental investigation has shown that both materials possess sufficient physico-mechanical properties to resist intra-abdominal pressure and when implanted they cause an inconsiderable inflammatory reaction followed by the formation of a solid connective tissue capsule. The endoprosthesis "Esfil" was used for plasty of the abdominal wall in 51 patients with postoperative ventral hernias. The endoprosthesis "Esfil" was found to meet all the requirements made to endoprostheses for plasty of the abdominal wall. Its use in clinical practice allows the restoration of quality of life of such patients.

[The future of biomaterials in urology]
Grise, P. (2002), Prog Urol 12(6): 1305-9.
Abstract: The fields of application of implanted biomaterials will continue to grow, ranging from the use of catheters and slings for the genitourinary tract, to the production of tissues and organs. The scale of research has changed over recent years, passing from a macroscopic view to a microscopic view, resulting in a change from mechanical devices, such as prostheses, catheters and slings to the cellular unit and more particularly in vitro cell cultures. New techniques, such as gene therapy and cell reconstruction have been recently introduced into the field of urology. Prospective biocompatibility studies must be conducted to establish appropriate biocompatibility standards adapted to new materials. The development of these new materials required a multidisciplinary approach involving engineers, biologists and physicists. It must be conducted in specialized centres skilled in biocompatibility research and in close collaboration with a basic bioscience and clinical practice. In the future, synthetic biomaterials will have an almost unlimited range of mechanical properties allowing much more specific applications. Another improvement of materials will concern a reduction of the risk of infection, erosion, mineral deposits, migration of particles, secondary reactions, and finally improved durability. However, the long-term properties of synthetic materials will probably not be as good as those of natural or almost natural biomaterials derived from biotechnology by tissue engineering.

[The mechanism of degradation for the absorbable biomaterials poly(epsilon-caprolactone) in vitro and in vivo]
Chen, J., A. Ma, et al. (1997), Sheng Wu Yi Xue Gong Cheng Xue Za Zhi 14(4): 334-7.
Abstract: This study was intended to address the mechanism of the degradation for the bioabsorbable materials poly(epsilon-caprolactone) (PCL) in vitro and in vivo by measurement of changes in intrinsic viscosity, number average molecular weight and crystalliniy. The test demonstrated that the degradation in rabbit was quicker than that in vitro. This illustrates that the mechanism of bioerosion in vivo is as important as the nonenzymatic random hydrolytic cleavage of ester linkages. Regardless of the initial Mn of the sample, a linear relationship between ln[eta] and time was observed until the Mn decreased to about 5000. Before this decrease of Mn, the main mechanism of degradation is hydrolytic cleavage of ester groups, with an accompanying enzymatic surface erosion, but after this decrease of Mn, the bioerosion with weight loss plays a role more significant than that the hydrolytic reaction plays in the degradation. The morphological characteristics of PCL materials after and before erosion were also compared by means of Scanning Electron Microscopy.

[The methodological aspects of biological safety in the cryopreservation of pathogenic biomaterial for microbiological studies]
Kadetov, V. V., A. N. Terent'ev, et al. (1999), Klin Lab Diagn(8): 22-4.

[The question of the transmissibility of the results of subcutaneous tests of biomaterials from animals to humans]
Schreiber, H., F. Keller, et al. (1990), Z Exp Chir Transplant Kunstliche Organe 23(1): 23-5.
Abstract: The histologic estimation of the subcutaneous connective-tissue reaction at implants forms an important part of the biocompatibility test. The connective-tissue capsulae around titanium implants in man, guinea-pig, and Wistar-rat were analysed by a special test system because of the question concerning the transmission of results of animal experiments on the man. The subsidence process of the thickness of the connective-tissue capsule and of the cell count per measuring fields were represented in dependence on the time. The findings showed the fundamental similar course of wound healing in man, guinea-pig, and Wistar-rat by the influence of an implant.

[The relationship of metal intravascular stand's surface composition and design to haemocompatibility]
Xiao, M. and Y. Ling (2005), Sheng Wu Yi Xue Gong Cheng Xue Za Zhi 22(1): 217-20.
Abstract: Metal biomaterials must be biocompatible; especially, when they contact directly with blood, they must be haemocompatible. Now, stainless steel, tantalum and nickel-titanium shape memory metal alloy are normally made into intravascular stands that are used to stretch blood vascular and resume blood circulation. Intravascular stand's haemocompatibility is very important because it directly influences the occurrence of thrombogenesis in blood system. This paper briefly reviews the metal intravascular stand's surface property, interface reaction with blood, structure design and the research of haemocompatibility.

[The role of microwaves during cryopreservation of the biomaterials]
Hu, J. X. and H. B. Ying (2004), Sheng Li Ke Xue Jin Zhan 35(4): 371-3.

[The scanning tunneling microscope and the soft X-ray microscope: a challenge to atomic/molecular image of biomaterials]
Ohyama, J. and H. Kihara (1987), Tanpakushitsu Kakusan Koso 32(5): 411-6.

[The specific characteristics determined by nonbiological tests of mineral-based biomaterials used in dentistry. 7]
Mongiorgi, R., G. Valdre, et al. (1995), Minerva Stomatol 44(1-2): 69-74.
Abstract: In this work we relate about the results coming from crystallographic, physical and mineral tests taken on following biomaterials used in odontostomatology: reabsorbable Dac Blu, non reabsorbable Dac Blu, not reabsorbable atomized Dac Blu, not reabsorbable thin Dac Blu, reabsorbable Biocoral 450, Calcitite 2040-12, Orthogel, Apagen, BTF 65, Calcitite 4060-2, Osprogel, Bio-Oss, Biostite, Osprovit, Merck Hydroxiapatite. The data were obtained using the following tests: XRF, XRD, FTIR, TG, DTG, DTA, SEM. The results, although taken on few samples, showed that these biomaterials present a variability in some features, which can define the structural functionality.

[The specificity of surgery of congenital cataract with implantation of folding "Acrysof" IOL in children]
Kruglova, T. B. and N. S. Egiian (2005), Vestn Oftalmol 121(2): 43-4.
Abstract: Described in the paper are the results of surgical treatment of 25 children (37 eyes), aged 3 months to 12 years, with congenital and secondary cataracts. The treatment schemes were based on new technologies including tunnel incisions, continuous round anterior capsulorhexis and aspiration-irrigation as well as implantation of different-model posterior-chamber flexible "Acrysof' IOLs into the capsular sac or ciliary sulcus. A high treatment efficiency as well as a need in a differentiated approach to choosing an IOL fixation, diameter and technique of anterior capsulorhexis and a model of the implanted "Acrysof' IOL made with respect to individual age and clinical peculiarities of eyes of children with congenital cataracts as well as with respect to a potential general somatic pathology (galactosemia) are demonstrated.

[The study of influence of chitosan on clinical, metabolic and immune parameters in patients with cardiovascular diseases]
Pogozheva, A. V., E. K. Baigarin, et al. (2005), Vopr Pitan 74(4): 27-30.
Abstract: The investigation of influent of antiatherosclerotic diets with chitosan on clinical and metabolic parameters in patients with cardiovascular diseases. Results of the study show that enrichment of a diet with chitosan in patients with ishemic heart disease and hypertension improved clinic, immune status, antropometric levels and lipid spectrum of blood. The research has shown, that the use in the treat-preventive purposes chitosan is rather perspective.

[The surface status of polished restoration biomaterials after the use of a sodium bicarbonate spray: scanning electron microscopy]
Kuliralo, M. and N. Dourov (1990), Bull Group Int Rech Sci Stomatol Odontol 33(3-4): 131-6.
Abstract: The effects of an air-abrasive system on polished surfaces of restorative materials have been studied using scanning electron microscopy, metrology and profilography. Polished surfaces of composite resin, of amalgam and gold alloy show different alteration types in microtopography, in profile tracings and significant increased surface roughness after air-abrasive spraying; but ceramic and non-precious alloy surfaces are not affected. The composite resin surfaces should be repolished and amalgam and gold alloy surfaces made glossy after use of an air-abrasive system.

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