An Immunohistological Study on the Localization of Selected Bacteria in Advancing Bacterial Front of Human Deep-carious Teeth

Abstract

The characterization of advancing bacterial front of carious lesions is important not only for the pathogenesis of pulpitis, but also for the treatment of pulpal pathosis. We immunohistologically examined the prevalence and localization of selected bacteria in human deep-carious teeth. Fourteen specimens were obtained from extracted carious third molars that showed bacterial invasion in reparative dentin and/or dental pulp. The distribution of bacterial penetration was detected nonspecifically by Brown-Brenn stain and specifically enzyme-labeled antibody method with specific rabbit antisera against six bacteria. All of the samples showed the invasion of Lactobacillus plantarum in the reparative dentin. About 90% of the examined teeth showed the invasion of Streptococcus mutans, Micromonas micros and Lactobacillus casei in the reparative dentin. These four bacteria were also detected in the dental pulp with carious exposure. In contrast, the detection frequencies of Actinomyces viscosus and Streptococcus sanguinis in reparative dentin were about 40% and 20%, respectively. The present study revealed the features of advancing bacterial front of deep-carious teeth with irreversible pulpitis.