Biochemical composition and cariogenicity of dental plaque formed in the presence of sucrose or glucose and fructose

The composition of dental plaque formed in the presence of sucrose or gluco se and fructose and its relation to cariogenicity was evaluated. Twelve adu lt volunteers took part in this crossover study done in three phases of 28 days each. For each phase, an acrylic resin appliance containing four human dental enamel blocks was constructed for the volunteers. Solutions contain ing 20% sucrose or 10% glucose + 10% fructose were dripped onto the enamel blocks 8 times a day, while in the control group no solution was used, Enam el surface and cross-sectional microhardness results showed that dental pla que formed in the presence of sucrose was more cariogenic than that formed in the presence of glucose + fructose (p< 0.05). The concentration of alkal i-soluble carbohydrates in dental plaque was higher in the sucrose group th an in the control and glucose + fructose groups (pe 0.05). Although concent rations of Ca, P and F were lower in plaque formed in the presence of sucro se than glucose + fructose and the control, significant differences (pe 0.0 5) were only observed in relation to control. The electrophoretic profile o f the matrix proteins of dental plaque showed distinct patterns when it was formed in the absence or presence of the different carbohydrates. Although the results suggest that the high cariogenicity of dental plaque formed in the presence of sucrose can be mainly explained by the high concentration of insoluble glucans of its matrix, the low inorganic concentration and its protein composition may have some contribution. Copyright (C) 2000 S. Karg er AG, Basel.