Objective To establish a model of intracellular infection of human dental pulp fibroblast（HDPF） by Porphyromonas gingivalis in vitro. Methods HDPF was incubated with live Porphyromonas gingivalis with a multiplicitas of infection（MOI） from 100 for 0.5, 1.0, 2.0 hours. HDPF infected with live Porphyromonas gingivalis were observed by inverted microscope. Metronidazole, Penicillin, Streptomycin were added to the medium to kill any extracellular bacteria. Then the cells were lysed by sterile distilled water, dilutions of the lysates of cells were cultured anaerobically. Colony of invasive bacteria were then observed. HDPF exposed live Porphyromonas gingivalis with a MOI 50 and 100 for 1.0 hour, then cells survival rate were detected by MTT assay. Results After infected with Porphyromonas gingivalis 2.0 hours, cells were eumorphism. Porphyromonas gingivalis of incubation for 1.0, 2.0 hours was invasive cells. MTT assays indicated 99.07% cells survival rate with a MOI from 50 and 74.43% cells survival rate with a MOI from 100. Conclusion A model of HDPF intracellular infection with Porphyromonas gingivalis was successfully established in vitro.
