The effects of sucrose, fructose, and a mixture of glucose and fructose on the incidence of dental caries in monkeys (M. fascicularis)

Effects of glucose and sucrose variants of the caries-promoting Diet 2000 on the feeding patterns and parotid glands of prematurely weaned rats

OBJECTIVE

The hypothesis of this study was that feeding glucose instead of sucrose in the cariogenic Diet 2000 to rats weaned at age 18 days would result in greater light/dark differences in feeding activity and secretion and storage of parotid salivary enzymes.

DESIGN OF STUDY

Diet 2000 and a stock commercial diet (controls) were prepared in pelleted and powdered forms, as the increased mastication required by pellets has been shown to support circadian rhythms in rats. Food jars were weighed at lights on and just prior to lights off daily. Rats were euthanized at 25 days and their parotid glands removed, weighed, and analyzed for specific activities of the salivary enzymes α-amylase and deoxyribonuclease I.

RESULTS

Light/dark differences in feeding activity were strong in the rats fed the pelleted stock diet and both powdered and pelleted glucose 2000 diets, moderate with the pelleted sucrose 2000 diet, and not significant with the powdered sucrose 2000 and stock diets. Light/dark differences in the parotid salivary enzymes were strong with the powdered glucose 2000 diet and the pelleted forms of the glucose and sucrose 2000 and stock diets, and not significant with the powdered stock and sucrose 2000 diets.

CONCLUSION

Caries reportedly is higher in sucrose than glucose fed to rats in the standard powdered form of Diet 2000, mainly due to the colonizing advantage Streptococcus mutans gains with sucrose. These results suggest that additional factors are more feeding during lights on and less stimulation of parotid salivary secretion with the sucrose powder.

Sugars – The Arch Criminal?

Numerous lines of evidence have conclusively established the role of sugars in caries etiology and the importance of sugars as the principal dietary substrate that drives the caries process has not been scientifically challenged. While sugars appear to differ little in acidogenic potential, sucrose has been given special importance, as the sole substrate for synthesis of extracellular glucans. Water-insoluble glucans might enhance accumulation of mutans streptococci on smooth tooth surfaces and appear to enhance virulence by increasing plaque porosity, resulting in greater acid production immediately adjacent to the tooth surface. Data indicating that the sugar consumption/caries relationship is now weaker have led to suggestions that recommendations to restrict sugar consumption are no longer necessary. Clearly, fluoride has raised the threshold of sugar intake at which caries will progress to cavitation, but fluoride has its limits, and caries remains a serious problem for disadvantaged individuals in many industrialized countries and is a rising problem in many developing countries. A weakening of the sugar/caries relationship may also be explained by many technical, biological, behavioral and genetic factors. Future research should aim to determine the biologic and behavioral factors that influence caries risk. Measures to educate the public on the dangers of frequent sugar consumption, combined with recommendations for proper oral hygiene and fluoride use, are still warranted. Individual dietary counseling is highly recommended for patients at high caries risk. As dental caries is a preventable disease, each country must decide: what level of disease is society willing and able to tolerate?

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 glucose and fructose and its relation to cariogenicity was evaluated. Twelve adult 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 containing 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. Enamel surface and cross-sectional microhardness results showed that dental plaque formed in the presence of sucrose was more cariogenic than that formed in the presence of glucose + fructose (p<0.05). The concentration of alkali-soluble carbohydrates in dental plaque was higher in the sucrose group than in the control and glucose + fructose groups (p<0.05). Although concentrations of Ca, P and F were lower in plaque formed in the presence of sucrose than glucose + fructose and the control, significant differences (p<0.05) were only observed in relation to control. The electrophoretic profile of 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.

Biological mechanisms of early childhood caries

The present paper reviews biological issues in early childhood caries (ECC) in light of the current understanding of the field. Despite the general global decline in dental caries in the past decades, ECC has become a significant problem in many developing countries and some minority communities in western industrialized nations. Like other types of caries, ECC is caused by mutans streptococci that ferment dietary carbohydrates to produce acid attacks on susceptible teeth over a period of time. However, while the general etiology of ECC appears similar to that of other types of caries, the predisposing factors are still unclear. The biology of ECC may be modified by several factors unique to young children, related to the implantation of cariogenic bacteria, immaturity of the host defense systems, as well as behavioral patterns associated with feeding and oral hygiene in early childhood.

Fermentable simple sugars in self-administered medications as aetiologic agents in rampant caries. Case report

Sucrose is recognized as the most cariogenic carbohydrate. However, other simple sugars may act as substrates for cariogenic micro-organisms. The clinical features of an adult patient suffering from rampant caries are described. It was considered that the predominant aetiologic factor was prolonged intake of mineral supplements which contained the disaccharide lactose. The principal caries risk factors included drug-induced xerostomia and prolonged contact time with the substrate in a retentive form. Chemical analysis of the products revealed the presence of lactose together with starch or glucose. A strategy for preventive management prior to restorative therapy based on chlorhexidine and fluoride-containing products was followed. Possible contributions of sugar-containing medications to caries risk status are discussed.

Influence of sweetening agents in solution on dental caries in desalivated rats

Sucralose (trichlorogalactosucrose), sorbitol and aspartame in drinking water induced little or no caries in desalivated rats infected with Streptococcus sobrinus and Actinomyces viscosus and receiving their essential nutrition by gastric gavage. In contrast, sucrose and fructose induced extensive decay. Only sucrose could sustain implantation of Strep. sobrinus in these animals. The populations of A. viscosus were sparse (0.3-0.5%) in the animals given fructose and sucrose. Large populations of A. viscosus occurred in the controls and in those given sucralose, sorbitol and aspartame. In a second experiment, where animals were also desalivated and receive diet 2000 ad libitum, sucrose in solution promoted caries whereas sucralose, aspartame and saccharin were without effect. Addition of 10 parts/10(6) F overcame the caries-promoting effect of sucrose in solution. There was no interaction between fluoride and other sweetening agents that affected the incidence of caries.

Quantification of incipient approximal caries during fructose and sucrose consumption

The purpose of this study was to quantify the changes in the size of approximal caries lesions during regular sucrose or fructose consumption. The material consisted of the subjects in the 2-year Turku Sugar Study, with an observation period of 19 months. Planimetric evaluation showed a highly significant increase in the approximal lesions of both groups. There was no difference between the groups in the rate of the increase in the sizes of the lesions. Initially, small lesions increased at a higher rate than initially large lesions in both groups. It is concluded that a fructose diet enhances the progression of carious lesions as much as a sucrose diet.

The effects of sugars intake and frequency of ingestion on dental caries increment in a three-year longitudinal study

A three-year longitudinal study was carried out with a group of children, initially aged 11-15, residing in non-fluoridated rural communities in south-central Michigan. This report analyzes the relation between caries increment and consumption of sugars from all sources to see if accepted relationships have changed with the caries decline in the United States. There were 499 children who provided three or more 24-hour dietary recall interviews, and who received dental examinations at baseline and after three years. Caries increment averaged 2.91 DMFS over the three years, with 81% of new lesions on pit-and-fissure surfaces. Consumption of sugars from all sources averaged 156 g per day for males and 127 g per day for females, an average of 52 kg per person per year. Sugars constituted one-quarter of total caloric intake for both boys and girls, and the average number of eating occasions per day was 4.3. Children who consumed a higher proportion of their total energy intake as sugars had a higher increment of approximal caries, though there was little relation to pit-and-fissure caries. The average number of daily eating occasions was not related to caries increment, nor was the average number of sugary snacks (defined as foods with 15% or more of sugars) consumed between meals, but the average consumption of between-meal sugars was related to the approximal caries increment. When children were categorized by high caries increment compared with no caries increment, a tendency toward more frequent snacks was seen in the high-caries children.(ABSTRACT TRUNCATED AT 250 WORDS)

Isolation of a novel protein involved in the transport of fructose by an inducible phosphoenolpyruvate fructose phosphotransferase system in Streptococcus mutans

Fructose transport in Streptococcus mutans LG-1 is mediated by at least two distinct phosphoenolpyruvate fructose phosphotransferase systems. One system is constitutive and consists of membrane components enzyme II as well as enzyme I and heat-stable protein. The other system is inducible and requires, in addition to enzyme I and heat-stable protein, a soluble substrate-specific protein for catalytic activity. This protein factor, designated IIIfru, was purified by DEAE-cellulose chromatography, hydroxylapatite chromatography, molecular sieving on Sephadex G-75, and preparative electrophoresis. The purified preparation showed only one protein band, with a molecular weight of 12,600, on sodium dodecyl sulfate-urea-polyacrylamide gel electrophoresis, on gel electrophoresis with the discontinuous buffer Tris-glycine, and after electrofocusing in gel (pI congruent to 3.7). The molecular weight of the native protein determined by gel filtration at 4 degrees C was 51,000. Immunodiffusion experiments performed with immunoglobulins prepared against the purified IIIfru from S. mutans LG-1 suggested that other S. mutans strains possessed a IIIfru. No precipitin bands, however, were detected with extracts from S. salivarius, S. sanguis, S. lactis, S. faecalis, Staphylococcus aureus, Bacillus subtilis, Lactobacillus casei, and Escherichia coli.

Effect of specific antisera on adherence properties of the oral bacterium Streptococcus mutans

Antisera to Strep. mutans antigens B, glucosyltransferase (GTF) and a glucan-binding protein (GBP) reduced the build-up of this bacterium on glass surfaces in vitro; antiserum to antigen A and a control non-immune serum were without significant effect. The same sera were used to study the involvement of these antigens in cell-cell aggregation mediated by sucrose or water-soluble Dextran 2000. Antiserum to GTF and antigen B inhibited sucrose-dependent cell-cell aggregation of the organism by approximately 50 per cent; none of the antisera tested had any effect upon dextran-mediated aggregation. In the presence of sucrose, GTF and GBP became cell associated while the distribution of antigens A and B between culture supernatant and cell surface remained unchanged. Cells incubated in the presence of Dextran 2000 showed no change in the distribution of any of these antigens. It is concluded that the aggregation of Strep. mutans induced by sucrose or by dextran involves different cellular components. Consideration of these in-vitro results in relation to data from experiments in which macaque monkeys were immunized with purified Strep. mutans antigens suggests that inhibition of sucrose-dependent adherence is not the basis for protection against dental caries.