Cariogenicity of glucose, sucrose and amylopectin in rats and hamsters infected and noninfected with Streptococcus mutans

Clinical Study of the Change of pH Level in the Supragingival Plaque in Children after Taking Homeopathic Remedies

Objective: There are numerous publications on the parameters of conventional medications, which contribute to their cariogenic and erosive potential. Little is known about the homeopathic remedies (HR) and the changes in the oral cavity they lead to, especially during childhood.

Material and methods: The study involved 25 children (5-9 years of age). It monitored the change in plaque pH level after intake of three frequently used homeopathic remedies in five consecutive weeks. The pH level values were measured after the administration of the remedies, without HR intake, and after rinsing with 10% sucrose solution. Five groups were formed – two controls and three groups with results from the tested HR.

Results: A drop in the plaque pH level was observed after intake of all HR and in all tested individuals. The biggest decrease was observed at the 15th minute for all HR. At the 30th minute the greatest decrease was observed with the second remedy, and at 60th minute – with the first and second.

Conclusions: A dramatic decrease in the plaque pH level was observed after intake of each studied remedy. In many cases the drop was below the critical value of pH = 5.5. The low plaque pH values were maintained even at the 60th minute after the start of the study.

Sucrose promotes caries progression by disrupting the microecological balance in oral biofilms: an in vitro study

Sucrose has long been regarded as the most cariogenic carbohydrate. However, why sucrose causes severer dental caries than other sugars is largely unknown. Considering that caries is a polymicrobial infection resulting from dysbiosis of oral biofilms, we hypothesized that sucrose can introduce a microbiota imbalance favoring caries to a greater degree than other sugars. To test this hypothesis, an in vitro saliva-derived multispecies biofilm model was established, and by comparing caries lesions on enamel blocks cocultured with biofilms treated with sucrose, glucose and lactose, we confirmed that this model can reproduce the in vivo finding that sucrose has the strongest cariogenic potential. In parallel, compared to a control treatment, sucrose treatment led to significant changes within the microbial structure and assembly of oral microflora, while no significant difference was detected between the lactose/glucose treatment group and the control. Specifically, sucrose supplementation disrupted the homeostasis between acid-producing and alkali-producing bacteria. Consistent with microbial dysbiosis, we observed the most significant disequilibrium between acid and alkali metabolism in sucrose-treated biofilms. Taken together, our data indicate that the cariogenicity of sugars is closely related to their ability to regulate the oral microecology. These findings advance our understanding of caries etiology from an ecological perspective.

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.

The role of sucrose in cariogenic dental biofilm formation--new insight

Dental caries is a biofilm-dependent oral disease, and fermentable dietary carbohydrates are the key environmental factors involved in its initiation and development. However, among the carbohydrates, sucrose is considered the most cariogenic, because, in addition to being fermented by oral bacteria, it is a substrate for the synthesis of extracellular (EPS) and intracellular (IPS) polysaccharides. Therefore, while the low pH environment triggers the shift of the resident plaque microflora to a more cariogenic one, EPS promote changes in the composition of the biofilms' matrix. Furthermore, it has recently been shown that the biofilm formed in the presence of sucrose presents low concentrations of Ca, P(i), and F, which are critical ions involved in de- and remineralization of enamel and dentin in the oral environment. Thus, the aim of this review is to explore the broad role of sucrose in the cariogenicity of biofilms, and to present a new insight into its influence on the pathogenesis of dental caries.

Food starches and dental caries

Sucrose and starches are the predominant dietary carbohydrates in modern societies. While the causal relationship between sucrose and dental caries development is indisputable, the relationship between food starch and dental caries continues to be debated and is the topic of this review. The current view of dental caries etiology suggests that in-depth evaluation of the starch-caries relationship requires the consideration of several critical cariogenic determinants: (1) the intensity (i.e., the amount and frequency) of exposure of tooth surfaces to both sugars and starches, (2) the bioavailability of the starches, (3) the nature of the microbial flora of dental plaque, (4) the pH-lowering capacity of dental plaque, and (5) the flow rate of saliva. Studies of caries in animals, human plaque pH response, and enamel/dentin demineralization leave no doubt that processed food starches in modern human diets possess a significant cariogenic potential. However, the available studies with humans do not provide unequivocal data on their actual cariogenicity. In this regard, we found it helpful to distinguish between two types of situations. The first, exemplified by our forebears, people in developing countries, and special subject groups in more modern countries, is characterized by starch consumption in combination with a low sugar intake, an eating frequency which is essentially limited to two or three meals per day, and a low-to-negligible caries activity. The second, exemplified by people in the more modern societies, e.g., urban populations, is characterized by starch consumption in combination with significantly increased sugar consumption, an eating frequency of three or more times per day, and a significantly elevated caries activity. It is in the first situation that food starches do not appear to be particularly caries-inducive. However, their contribution to caries development in the second situation is uncertain and requires further clarification. Although food starches do not appear to be particularly caries inducive in the first situation, the possibility cannot be excluded that they contribute significantly to caries activity in modern human populations. The commonly used term "dietary starch content" is misleading, since it represents a large array of single manufactured and processed foods of widely varying composition and potential cariogenicity. Hence, increased focus on the cariogenicity of single starchy foods is warranted. Other aspects of starchy foods consumption, deserving greater attention, include the bioavailability of starches in processed foods, their retentive properties, also in relation to sugars present (starches as co-cariogens), their consumption frequency, the effect of hyposalivation on their cariogenicity, and their impact on root caries. The starch-caries issue is a very complex problem, and much remains uncertain. More focused studies are needed. At present, it appears premature to consider or promote food starches in modern diets as safe for teeth.

Associations between dietary intake, dental caries experience and salivary bacterial levels in 12-year-old English schoolchildren

A population of 328 12-yr-old English schoolchildren, consuming their normal diets, was investigated in a cross-sectional study to determine the interactions between caries experience, oral hygiene status as gingival index (GI), dietary intake (as number of eating events per day and the number of eating events per day at which sugar-containing foodstuffs, confectionery or starch-containing foods were consumed) and salivary levels of caries-associated micro-organisms (mutants streptococci, lactobacilli and yeasts). The mean (+/- SD) decayed, missing and filled surfaces (DMFS) (excluding precavitation lesions) score was 3.05 +/- 3.85 and 5.72 +/- 5.00 (including precavitation lesions). The DMFS scores were significantly related to the salivary levels of caries-associated micro-organisms and to the number of eating events per day for total number of eating events and the number of eating events at which sugar-containing foods or confectionery were consumed. These associations were apparent in both bivariate and partial correlation coefficients with the caries-associated micro-organisms and GI controlled. The total daily intakes of food types, except for starch, were not associated with caries experience. No significant correlations were found between intake of food types and salivary levels of caries-associated micro-organisms except that the mean number of confectionery-eating events was correlated with lactobacillus levels (r = 0.136, p < 0.01). The salivary levels of mutans streptococci, lactobacilli and yeasts were significantly correlated with GI scores. These data do not indicate simple associations between dietary intake, caries and levels of caries-associated micro-organisms. Poor oral hygiene, in children consuming unrestricted diets, may influence the salivary levels of mutans streptococci, lactobacilli and yeasts irrespective of the frequency or amount of sugar consumed. Multiple regression analyses revealed that three variables--GI (probably an indicator of toothbrushing behaviour with a fluoride-containing toothpaste), salivary concentration of lactobacilli and frequency of ingestion of confectionery/sugary foods--were independently and positively related to caries experience.

Dental cariogenic evaluation of foods using human plaque pH and an experimental rat-caries model

Five well-characterized foods were used to compare two systems for estimating the cariogenic potential of food: human plaque-acidity using interdental metallic touch electrodes, and cariogenicity testing in rats. Both systems identified the same food as the least cariogenic or acidogenic food and identified the same three foods as being both cariogenic in rats and acidogenic in man, although the ranking of these foods differed. The systems differed in their assessment of potato chips, a food high in cooked starch and low in free sugars. The results confirmed that non-acidogenic foods are non-cariogenic, but that foods acidogenic in man may exhibit a greater range of cariogenicity in rats. Data from both human plaque pH studies and rat caries models may permit better assessment of cariogenic potential of foods containing fermentable carbohydrates.

The cariogenicity of sucrose, glucose and maize starch in gnotobiotic rats mono-infected with strains of the bacteria Streptococcus mutans, Streptococcus salivarius and Streptococcus milleri

Twenty-one-day-old weanling gnotobiotic WAG/RIJ rats were mono-infected with Streptococcus mutans NCTC 10832, Streptococcus salivarius JMB or Streptococcus milleri NCTC 11169, and maintained on a high carbohydrate diet containing sucrose, glucose or maize starch for 21-days. Fissure caries developed with all combinations of streptococcal strain and carbohydrate except maize starch/Streptococcus salivarius JMB. Caries incidence was highest with Streptococcus mutans NCTC 10832. For all species, the ranking of carbohydrates by cariogenic potential was sucrose greater than glucose greater than maize starch.