Dissolution studies of hydroxyapatite and glass-reinforced hydroxyapatite ceramics

• Type: Article in International Scientific Journal
• Date: 2003

Authors

A. C. Queiroz (Author) Other; José Domingos Santos (Author) FEUP; Fernando Jorge Monteiro (Author) FEUP; M. H. Prado da Silva (Author) Other

Journal

Title: Materials Characterization

Vol. 50 No. 2-3

Pages: 197-202

ISSN: 1044-5803

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 23 Citations

ISI Web of Science

Scopus - 31 Citations

COMPENDEX

Scientific classification

FOS: Engineering and technology > Materials engineering

Other information

Authenticus ID: P-000-HME

DOI: 10.1016/s1044-5803(03)00092-5

Abstract (EN): In the continuous agitation assays, glass-reinforced hydroxyapatite (GR-HA) was shown to form a calcium phosphate (CaP) layer, but hydroxyapatite (HA) only formed dispersed precipitates. The formation of this layer was first detected on the GR-HA with a 7.5% glass addition (7.5 GR-HA) after only 3 days of immersion in simulated body fluid (SBF). The time required for layer formation decreased as the amount of glass added to the HA increased. The dissolution rate of the materials followed a similar pattern, i.e. the dissolution rate for GR-HA was higher than for HA, and increased with the addition of glass. The immersion of 7.5 GR-HA in water showed almost linear dissolution kinetics over the immersion periods (3, 7, 15, 30 and 60 days). The concentration of calcium ions in solution and the scanning electron microscopy (SEM) analysis of the 7.5 GR-HA specimens immersed in water and in SBF revealed a clear competition between the material dissolution and the precipitation of a CaP phase. Fourier transformed infrared spectroscopy with alternated total reflectance (FTIR-ATR) analysis indicated that the CaP phase that formed during longer immersion times (30 and 60 days) could be a carbonate-substituted CaP precipitate. As expected from previous work, the GR-HA behavior in terms of its in vitro bioactivity is higher than HA because a homogeneous CaP layer is formed and the precipitation occurs faster. From the dissolution test and in accordance with the chemical composition of the samples, GR-HA was more soluble than HA.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 6