Composition of dental plaque formed in the presence of sucrose and after its interruption

Abstract

Since dental plaque reservoirs of fluoride (F), calcium (Ca) and inorganic phosphorus (Pi) are susceptible to decreases in pH, this in situ crossover study was conducted to test the hypothesis that the low concentration of these ions in plaque, formed in the presence of sucrose, could be attributed merely to the fermentation of this sugar. Eleven volunteers wore palatal appliances containing 6 human enamel blocks during two stages. In each stage, the treatments were either 20% sucrose solution or distilled deionized water, which were dripped onto the blocks 8 times a day. After 28 days, in each stage, the dental plaque formed on two blocks was collected, the treatment was inverted and after a further 24 and 48 h, the biofilm formed was collected from the other blocks. The concentration of acid-soluble F, Ca and Pi, and the concentration of insoluble polysaccharide (IP) were determined in the dental plaque. Statistically lower concentrations of F, Ca and Pi, and a higher concentration of IP were found in the 28-day biofilm formed in the presence of sucrose than in its absence; after the treatment inversion the change in F, Ca and Pi was not statistically significant, but the IP concentration changed significantly. The hypothesis was rejected because change in concentration of F, Ca and Pi is not due to fermentation of the sucrose.

Effect of dietary sugars on dual-species biofilms of Streptococcus mutans and Streptococcus sobrinus – a pilot study

“…There are a considerable number of studies suggesting that sucrose is the most cariogenic carbohydrate [11][12][13]15 . Nevertheless, this study shows that other fermentable carbohydrates may also influence biomass formation and biofilm acidogenicity.…”

“…It is known that S. mutans produces elevated amounts of extracellular polysaccharides (EPS) when sucrose is available, which provides support to development and accumulation of microcolonies and increase the cohesiveness and structural integrity of the biofilm 29 . Intracellular polysaccharides (IPS) are also synthesized and provide bulk to biofilms 12,13 .…”

“…Animals fed with carbohydrates exhibited formation of higher amounts of coronal plaque on the smooth surfaces of the tooth 11 . The fermentation of sucrose produces large amounts of acids within biofilms and serves as a substrate for extracellular and intracellular polysaccharide synthesis [12][13][14] . Extracellular polysaccharides increase porosity of the biofilm matrix, allowing carbohydrate diffusion through the biofilm.…”

“…Extracellular polysaccharides also increase microorganism adhesion and accumulation, mainly of S. mutans 13,15 . Intracellular polysaccharides are reservoirs of carbohydrates that promote pH drop during nutrient deprivation, prolonging the exposure of tooth surfaces to organic acids 12 .…”

“…However most of them have focused just on sucrose and/or glucose [12][13][14][20][21][22][23][24] . At present, little is known about the role of maltose and lactose.…”