Cai-lian Zhu1, Zheng Liu, Jiang-yun Sheng. 1. Shanghai Research Institute of Stomatology, Ninth People's Hospital, Shanghai Second Medical University, Shanghai 200011, China.
Abstract
OBJECTIVE: To figure out the effects of organic weak acids, benzoate, citric acid and malic acid on the main cariogenic bacteria S.mutans Ingbritt. To evaluate the possibility of above weak acids as anti-caries reagents. METHODS: S.mutans Ingbritt was inoculated into tryptic soy broth containing different concentrations of fluoride, benzoate, citric acid and malic acid, grew in anaerobic conditions at 37 degrees centigrade for 48h. The final pH values of suspension were measured. RESULTS: Fluoride had best inhibitory effect on S.mutans Ingbritt in low concentrations, whereas other 3 weak acids, benzoate, citric acid and malic acid could inhibit S.mutans Ingbritt in a higher concentrations. The order of effectiveness was fluoride>malic acid>benzoate>citric acid. CONCLUSION: Fluoride has the best inhibitory effect on S.mutans producing acid ability. Though weak acids benzoate, malic acid and citric acid in high concentration had different inhibitory effects on S.mutans Ingbritt, however high concentration of organic acids can make enamel demineralization.
OBJECTIVE: To figure out the effects of organic weak acids, benzoate, citric acid and malic acid on the main cariogenic bacteria S.mutans Ingbritt. To evaluate the possibility of above weak acids as anti-caries reagents. METHODS:S.mutans Ingbritt was inoculated into tryptic soy broth containing different concentrations of fluoride, benzoate, citric acid and malic acid, grew in anaerobic conditions at 37 degrees centigrade for 48h. The final pH values of suspension were measured. RESULTS:Fluoride had best inhibitory effect on S.mutans Ingbritt in low concentrations, whereas other 3 weak acids, benzoate, citric acid and malic acid could inhibit S.mutans Ingbritt in a higher concentrations. The order of effectiveness was fluoride>malic acid>benzoate>citric acid. CONCLUSION:Fluoride has the best inhibitory effect on S.mutans producing acid ability. Though weak acids benzoate, malic acid and citric acid in high concentration had different inhibitory effects on S.mutans Ingbritt, however high concentration of organic acids can make enamel demineralization.