



@article {2569,
	title = {Glass-reinforced hydroxyapatite composites: Fracture toughness and hardness dependence on microstructural characteristics},
	journal = {BiomaterialsBiomaterials},
	volume = {20},
	year = {1999},
	note = {Cited By (since 1996): 65Export Date: 21 November 2012Source: ScopusCODEN: BIMADdoi: 10.1016/S0142-9612(99)00112-XPubMed ID: 10535820Language of Original Document: EnglishCorrespondence Address: Santos, J.D.; Laboratorio de Biomateriais, Instituto de Engenharia Biomedica, INEB, Rua do Campo Alegre 823, 4150 Porto, PortugalChemicals/CAS: alpha-tricalcium phosphate; Biocompatible Materials; calcium phosphate, 10103-46-5; Calcium Phosphates; Composite Resins; dicalcium phosphate anhydrous, 7757-93-9; Durapatite, 1306-06-5; monocalcium phosphate; tetracalcium phosphateReferences: Akao, M., Aoki, H., Kato, K., Mechanical properties of sintered hydroxyapatite for prosthetic applications (1981) J Mater Sci, 16, pp. 809-812;Martin, R.I., Brown, P.W., Mechanical properties of hydroxyapatite formed at physiological temperature (1995) J Mater Sci Mater Med, 6, pp. 138-143; 
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Lopes, M.A., Monteiro, F.J., Santos, J.D., Glass reinforced hydroxyapatite composites: Secondary phase proportions and densification effects on biaxial bending strength (1999) J Appl Biomater, , in press; 
Lopes, M.A., Knowles, J.C., Kuru, L., Santos, J.D., Monteiro, F.J., Flow cytometry for assessing biocompatibility (1998) J Biomed Mater Res, 4, pp. 649-656; 
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},
	month = {1999///},
	pages = {2085 - 2090},
	publisher = {Elsevier Science Ltd},
	abstract = {Fracture toughness and hardness properties of CaO-P                        2O
                        5 glass-reinforced hydroxyapatite composites have been assessed using indentation techniques and results calculated according to Laugier and Evans{\textquoteright} equations. Both properties showed to be dependent upon several microstructural characteristics, namely residual porosity and the percentage of secondary β and α tricalcium phosphate phases in the structure of the composites. Composites presented a Palmqvist-type indentation crack system, which is the specific crack system addressed by Laugier{\textquoteright}s approach. Fracture toughness determinations according to Evan{\textquoteright}s equation, which is a universal one and adapted to both median and Palmqvist crack systems, did not correlate well with Laugier determinations. Copyright (C) 1999 Elsevier Science Ltd.
Fracture toughness and hardness properties of CaO-P
                        2O
                        5 glass-reinforced hydroxyapatite composites have been assessed using indentation techniques and results calculated according to Laugier and Evans{\textquoteright} equations. Both properties showed to be dependent upon several microstructural characteristics, namely residual porosity and the percentage of secondary β and α tricalcium phosphate phases in the structure of the composites. Composites presented a Palmqvist-type indentation crack system, which is the specific crack system addressed by Laugier{\textquoteright}s approach. Fracture toughness determinations according to Evan{\textquoteright}s equation, which is a universal one and adapted to both median and Palmqvist crack systems, did not correlate well with Laugier determinations.
},
	keywords = {article, Biocompatible Materials, Biomaterials, calcium phosphate, Calcium phosphates, ceramics, Composite materials, Composite Resins, Cracks, Durapatite, Evan{\textquoteright}s equation, Fracture toughness, glass, hardness, hydroxyapatite, Hydroxyapatite-glass composites, Indentation techniques, Kinetics, Laugier equations, material state, mechanical stress, Microscopy, Electron, Scanning, Microstructure, Palmqvist crack systems, Phosphate minerals, porosity, priority journal, Stress, Mechanical, tensile strength, Tricalcium phosphate},
	isbn = {01429612 (ISSN)},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-0033231746\&partnerID=40\&md5=55066a0fcfb28ee10321c5820371f75a},
	author = {Lopes, M.A. and Monteiro, F.J. and Santos, J.D.}
}
