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Cariogenic Potential (cariogenic + potential)
Selected AbstractsCharacterization of the Streptococcus sobrinus acid-stress response by interspecies microarrays and proteomicsMOLECULAR ORAL MICROBIOLOGY, Issue 5 2010A.R. Martinez Summary Streptococcus mutans and Streptococcus sobrinus are considered the primary organisms responsible for human dental caries. The ability to generate acids and to adapt to low pH conditions is directly associated with the cariogenic potential of these bacteria. To survive acidic conditions, both species have been shown to mount an acid-tolerance response (ATR). However, previous characterization of the S. sobrinus ATR identified critical differences in the mechanisms of acid adaptation between S. mutans and S. sobrinus. Here, interspecies microarray and proteomic approaches were used to identify novel, previously unrecognized genes and pathways that participate in the S. sobrinus acid-stress response. The results revealed that, among other things, metabolic alterations that enhance energy generation and upregulation of the malolactic fermentation enzyme activity constitute important acid-resistance properties in S. sobrinus. Some of these acid adaptive traits are shared by S. mutans and might be considered optimal targets for therapeutic treatments designed to control dental caries. [source] Relationship between quantitative assessments of salivary buffering capacity and ion activity product for hydroxyapatite in relation to cariogenic potentialAUSTRALIAN DENTAL JOURNAL, Issue 2 2008H Aiuchi Abstract Background:, The ion activity product for hydroxyapatite (IpHA) is a comprehensive parameter reflecting pH, calcium and phosphate ion concentration in saliva which govern the degree of saturation with respect to the dissolving tooth mineral. The aim of this study was to evaluate the relationship between quantitative assessments of salivary buffering capacity and IpHA in relation to cariogenic potential. Methods:, Stimulated whole saliva was collected from 33 patients, and the initial pH of samples was measured using a hand-held pH meter. Then samples were titrated with 0.1 N HCl to evaluate buffering capacities and divided into three groups (high, medium and low). After measuring concentrations of calcium and phosphate ions in the samples, IpHA was calculated using the values of the ion concentrations and pH. Differences in the mean pH values, the concentrations of calcium, phosphate ions and log[IpHA] among three groups were analysed using the Kruskal Wallis and the Mann-Whitney non-parametric test, p < 0.05. Results:, After HCl 50 ,L titration, there were statistical differences of the mean pH and IpHA among each buffering capacity group. Moreover, after 50 ,L HCl titration, there was an excellent correlation between the buffer capacity and log[IpHA]. Conclusions:, The pH change for saliva after HCl titration has a significant influence on the rate of IpHA. [source] The effect of carbon source and fluoride concentrations in the streptococcus mutans biofilm formation,BIOCHEMISTRY AND MOLECULAR BIOLOGY EDUCATION, Issue 5 2004Tony P. Paulino Abstract The main objective of this class experiment is to show the influence of carbon source and of different fluoride concentrations on the biofilm formation by the bacterium Streptococcus mutans. The observation of different biofilm morphology as a function of carbon source and fluoride concentration allows an interesting discussion regarding the metabolic pathways that lead to cavity development, about the role of fluoride on this disease prevention, and also on the importance of biofilm formation to the cariogenic potential of this bacterium, one of the main responsible for this multifatorial disease appearance. On addition to that, the low execution cost and the simple technical apparatus makes this experiment easy to perform. [source] | ||||||||||