Analyzing Of Adhesion Rate Of Different Genotype Streptococcus Mutans Isolated From Children With Different Caries Experience In Different Sucrose Concentration

Objective:The aim of this study is to compare the adhesion ability of different genotype Streptococcus mutans isolated from children with different caries experience in different sucrose concentration, and to analyze the role of different concentration of sucrose in the process of dental caries to occur. Methods:The 45 isolated strains of Streptococcus mutans with different genotypes were chosen as test bacteria. Then divided into three groups:group of high caries-susceptibility (dmft≥6), group of middle caries-susceptibility (6＞dmft≥4), group of caries-free (dmft=0). The strains were reanimated on BHI plates in anaerobic condition (80%N2,10%H2,10%CO2) at 37℃for 48 hours, then inoculated in BHI and cultivated in anaerobic condition (80%N2,10%H2,10%CO2) at 37℃for 18 hours. After the smear exam and biochemical identification, the strains then were inoculated into 3ml BHI which contains different concentration of sucrose. Use UV spectrophotometer to measure the absorbance of experimental samples, then compared the difference adhesion ability of the strains with different genotypes. Results:There was significant difference in adhesion ability among the different genotypes of strains isolated from children with different caries susceptibility. Among all the three group, the adhesion ability of high caries-susceptibility is the highest, then is middle caries-susceptibility, and caries-free group is the lowest. In the same group, The more genotypes the strain has, the more adhesion ability the strain produced, there were significant difference in the adhesion ability among the different genotypes of strains. Sucrose plays an important role in the process of dental caries occurrence. The higher concentration of sucrose the culture contains the higher adhesion ability the strain has. In the same concentration group, The more genotypes the strain has, the more adhesion ability it has there were significant difference in the adhesion ability among the different genotypes of strains Conclusion:There were significant difference in adhesion ability among the different genotypes of strains isolated from children with different caries susceptibility. Among all the three group, the adhesion ability of high caries-susceptibility is the highest, and that of caries-free group is the lowest. The more genotypes the strain has, the more adhesion ability it produced. Sucrose plays an important role in the process of dental caries occurrence. The higher concentration of sucrose the culture contains, the higher adhesion ability the strain has.