The influence of proteins on demineralization kinetics of hydroxyapatite aggregates

• Published in: Journal of biomedical materials research. Part A 2010-09, Vol.94A (3), p.972-977
• Main Authors: Kosoric, Jelena, Hector, Mark P., Anderson, Paul
• Format: Article
• Language: English
• Subjects: Aggregates; Animals; Biological and medical sciences; bovine serum albumin; Cattle; demineralization; Demineralizing; Durapatite - chemistry; Durapatite - metabolism; Fundamental and applied biological sciences. Psychology; Hydroxyapatite; kinetics; Materials Testing; Mathematical models; Mouth. Exocrine and endocrine salivary glands. Teeth. Esophagus; Porosity; protein; Proteins; Reproduction; Salivary Proteins and Peptides - chemistry; Salivary Proteins and Peptides - metabolism; Saturation; Serum Albumin, Bovine - chemistry; Serum Albumin, Bovine - metabolism; Surface energy; Tooth Demineralization - metabolism; Vertebrates: digestive system
• ISSN: 1549-3296; 1552-4965; 1552-4965
• DOI: 10.1002/jbm.a.32759

Salivary proteins influence the biomineralization of hydroxyapatite (HAp) within enamel. Their effect on the crystal growth has been extensively studied, but, their effect on demineralization kinetics is less well investigated. In this study bovine serum albumin (BSA) was used as a model protein to measure its effect on demineralization kinetics of hydroxyapatite aggregates using scanning microradiography (SMR). HAp aggregates (8 and 20% porous) were cut into 5 × 5 × 2 mm blocks. SMR cells were prepared containing hydroxyapatite blocks. BSA was added to demineralising solutions (0.1 mol L−1 acetic acid, buffered to pH 4.0; degree of saturation zero and 0.062 respectively) at a concentration range 0.76–75.8 μmol L−1. Demineralising solution without added BSA was used as a control. The demineralising solutions were circulated past the samples at 0.4 mL min−1. SMR was used to measure the rate of mineral loss (RMLHAp) at 14 points in each sample repeatedly for 3 weeks. The results show that BSA increases or decreases the RMLHAp depending on; BSA concentration, HAp porosity, and the degree of saturation of the demineralising solution. It is suggested that BSA influences demineralization kinetics of HAp either by modifying solution properties, or, by affecting the surface energy of hydroxyapatite. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010