Abstract:

Objective　In order to investigate the effect of PABA produced byStreptococcus sanguison microecological balance of subgingival plaque, different concentrations of PABAwere applied to see if it can influence the form and adherence of P.gingivalis.Methods　After adding different concentrations of PABA into 1/2 concentration of BHI media, an anaerobic tech- nique was used to cultureP.gingivalis.P.gingivalisgrew in the medium was observed by a scanning electron microscope.Re- sults　Excessively high or low PABA concentration could influence the form and adherence ofP.gingivalis.Conclusion　PA- BA produced byStreptococcus sanguiscan affect the form and adherence ofP.gingivalis.It indicates thatStreptococcus sanguis plays regulative effect on the microecological balance of subgingival plaques.

Key words: para-aminobenzoic acid, Porphyromonas gingivalis, scanning electron microscope, adherence