Adsorción Bacteriana sobre Hidroxiapatita Sintética, Esmalte y Dentina.

APELLA , M. C.; BLESA, M. A.; MORANDO, P. J.; OPEZZO, O.; PIZARRO, R.; VENEGAS, S. C.

Atibaia, San Pablo, Brasil. 2 al 5 de setiembre de 2007

Otro; 24 Reunião Anual SBPqO; 2007

Sociedade Brasileira de Pesquisa Odontológica

Hydroxyapatite (HAP), main inorganic component of bone and dental tissue, is used as a biomaterial for bone substitution. Implanted biomaterials interact with the surrounding fluids, forming a biofilm by adsorption of organic and inorganic compounds, and by bacterial colonization. In this work, natural and synthetic samples of HAP and selected bacteria are characterized, using a battery of techniques: Fourier transform infrared spectroscopy in the attenuated total reflection mode (FTIR-ATR), X-ray diffraction, scanning electron microscopy (SEM) with X-ray energy dispersive analysis (EDAX), atomic force microscopy (AFM) and electrophoretic mobility. Furthermore, the influence of Ca2+ on the microbial adsorption of HAP was also studied both by direct (bacterial isotopic labeling with 14C thimidine) and indirect methods (bacterial count in the supernatant). Bacterial adsorption on HAP tablets presents a Langmuir type behavior at low coverage whereas multilayers appear at high coverage. Adhesion mediated by exogenous Ca2+ depends on the hydrophobic properties of each strain and the electrical properties of bacterial and solid surfaces. Thus, HAP is found to be a good dental surface model for in vitro studies of the interactions bacteria-substrate and may be used to determine the conditions that lead to microbial colonization. (Support: CONICET-ANPCyT-CIUNT)