Toxicity of sonicated extracts of Bacteroides gingivalis on human pulpal cells and L929 cells in vitro

Abstract

Human pulpal fibroblasts and L929 cells were treated with sonicated extracts of two strains of Bacteroides gingivalis (W83 and ATCC 33277). The cell reaction was evaluated by monitoring cell growth and DNA synthesis. Light and scanning electron microscopic analysis were used to evaluate morphological changes of the cells. Extracts from both bacterial strains exerted a growth inhibitory effect on the cells. The pulpal cells were more sensitive than L929 cells. The ATCC 33277 strain of B. gingivalis was more cytotoxic than the W83 strain. Pulpal cells appeared to be markedly affected on the microscopic level. The diffusion of these toxic bacterial by-products, through dentin to the pulp, may account for pulpal cell damage that contributes to the initiation of pulpal pathosis.