Antibacterial activity of dentine and pulp extracellular matrix extracts

Abstract

To determine whether extracellular matrix (ECM) preparations from pulp (pECM) and dentine (dECM) possess antimicrobial activity. Dentine and pulp ECM preparations were isolated with 10% ethylenediaminetetraacetic acid (EDTA), pH 7.2 and sequential use of 0.5mol L(-1) NaCl, pH 11.7 and 0.1mol L(-1) tartaric acid, pH 2.0, respectively, with protease inhibitor inclusion throughout. Antimicrobial activity against Streptococcus mutans, Streptococcus oralis and Enterococcus faecalis was assessed using turbidity as a measure of bacteria growth. The cytotoxicity of the extracts on primary pulp cells was also determined by lactate dehydrogenase (LDH) release. Statistical analysis of data was performed using paired student's t-tests. Extracellular matrix extracts from the pulp and dentine showed antibacterial activity against three types of anaerobic bacteria associated with dental disease (P< 0.05). The ECM extracts demonstrated no significant cytotoxic effect on pulpal cells at the concentrations used for antibacterial activity. The bacteriostatic antibacterial activity of pECM and dECM indicates that the release of these matrix molecules from pulp and dentine may contribute to defence responses during dental disease, treatment and repair.