title: Nucleation and growth of octacalcium phosphate on treated  titanium by immersion in a simplified simulated body fluid.
abstract: A simplified simulated body fluid solution (S-SBF) was used to study the kinetics and mechanism of nucleation and growth of octacalcium phosphate (OCP) on the surfaces of alkali and heat-treated titanium samples. After the alkali and heat treatments, the samples were soaked in S-SBF for periods varying up to 24 h. A thin layer of poorly crystallized calcium titanate was formed after 15 min of immersion, allowing for the deposition of another layer of amorphous calcium phosphate (ACP). After 2.5 h of immersion, OCP nuclei were observed on the surface of the ACP layer. After 5 h of immersion in S-SBF solution, the specimens were completely covered with a homogeneous plate-like layer of OCP. Analyses by transmission electron microscopy revealed that nucleation and growth of OCP occurred concomitantly to the crystallization of ACP in hydroxyapatite (HA). This transformation took place by solid-state diffusion, forming a needle-like HA structure underneath the OCP film.
authors.affiliation: Department of Mechanical Engineering, Center of Technological Science, State University of Santa Catarina, Campus Universitario, Bairro Bom Retiro, 631, Joinville 89223-100, SC, Brazil. gemelli@joinville.udesc.br
authors.forename: Enori
authors.initials: E
authors.lastname: Gemelli
authors.forename: Cristiane Xavier
authors.initials: CX
authors.lastname: Resende
authors.forename: Gloria Dulce
authors.initials: GD
authors.lastname: de Almeida Soares
mesh_terms: D001826:Body Fluids / Q000737:chemistry*; D002130:Calcium Phosphates / Q000737:chemistry*; D003460:Crystallization; D017886:Durapatite / Q000032:analysis / Q000737:chemistry; D007101:Immersion; D008855:Microscopy, Electron, Scanning; D012996:Solutions; D014025:Titanium / Q000032:analysis / Q000737:chemistry*
chemical_list: D002130:Calcium Phosphates; D012996:Solutions; C519480:amorphous calcium phosphate; C022045:octacalcium phosphate; D017886:Durapatite; D014025:Titanium
references.citation: Biomaterials. 2003 Apr;24(9):1541-8
references.pmid: 12559814
references.citation: Int J Oral Maxillofac Implants. 2002 Nov-Dec;17(6):811-5
references.pmid: 12507240
references.citation: Biomaterials. 2005 Aug;26(24):4938-43
references.pmid: 15769528
references.citation: Biomaterials. 2004 Jun;25(13):2525-32
references.pmid: 14751737
references.citation: Biomaterials. 2005 Apr;26(10):1097-108
references.pmid: 15451629
references.citation: Adv Dent Res. 1987 Dec;1(2):306-13
references.pmid: 3504181
references.citation: Biomaterials. 2004 May;25(10):1779-86
references.pmid: 14738841
references.citation: J Biomed Mater Res. 2001 Dec 5;57(3):441-8
references.pmid: 11523039
references.citation: Biomaterials. 2005 Jun;26(16):3029-37
references.pmid: 15603798
references.citation: Biomaterials. 2004 Mar-Apr;25(7-8):1187-94
references.pmid: 14643592
references.citation: Ann Periodontol. 2000 Dec;5(1):56-67
references.pmid: 11885182
references.citation: Biomaterials. 2003 Jun;24(13):2125-31
references.pmid: 12699649
references.citation: Biomaterials. 2005 Dec;26(35):7350-6
references.pmid: 16023203
references.citation: Biomaterials. 2002 May;23(9):1921-30
references.pmid: 11996032
references.citation: Bone. 2006 Sep;39(3):431-3
references.pmid: 16581322
references.citation: Calcif Tissue Int. 2003 May;72(5):610-26
references.pmid: 12724829
references.citation: Biomaterials. 2005 Jun;26(16):2857-65
references.pmid: 15603781