Effects of Parafilm and cheese chewing on human dental plaque pH and metabolism

M, Joshi AB, Reenayai N. Evaluation of the Cariogenic Potential and Total Antioxidant Capacity of Saliva after the Consumption of Candies and Paneer: An In Vivo Study

Aim The present study was performed to assess and compare the changes in pH, calcium, phosphorus, alkaline phosphatase, and the total antioxidant capacity (TAC) of saliva after consuming candies, followed by rinsing with water and consumption of paneer.

Materials and Methods Baseline saliva of 5 mL was collected from 60 children and they were asked to chew on candies. After 10 minutes of intake of candies, 5 mL of saliva was collected. They were then divided into two groups of 30 each and test products were given. Group 1: rinse with water and group 2: chew 20 g of paneer and swallow. Saliva of % mL was collected after 10, 20, and, 30 minutes from the study groups. The saliva samples collected were assessed for pH, calcium, phosphorus, alkaline phosphatase, and TAC. The data were analyzed using the paired t-test and post hoc Tukey's test.

Results The pH, calcium, phosphorus, and alkaline phosphatase decreased from baseline values after consuming candies significantly (p < 0.001). These increased after rinsing with water and consumption of paneer which was statistically significant (p < 0.001). The TAC values increased significantly after consuming candies and decreased after rinsing with water and consumption of paneer which was substantial for both the groups.

Conclusion Consumption of candies created a cariogenic milieu. Both the study groups were effective in the reversal of the cariogenic potential. The consumption of paneer caused remineralizing properties and showed superior results than rinsing with water.

Carbonic anhydrase VI activity in saliva and biofilm can predict early childhood caries: A preliminary study

AIM

This study aimed to investigate whether carbonic anhydrase VI activity (CA VI_ACT ), pH, and buffering capacity (BC) in saliva and biofilm could predict the number of lesion occurrence and early childhood caries (ECC).

DESIGN

A cross-sectional study was performed in a sample of 44 children aged 4 to 5 years who were examined regarding their caries status (dmfs + active white spot lesions-WSL) and allocated into two groups: ECC and caries-free (CF). Saliva and biofilm were collected to determine pH, BC, and CA VI_ACT . Data were analyzed using the Student t test, and multiple linear regression and logistic regression analyses followed by the ROC curve.

RESULTS

Children with ECC exhibited lower pH and BC in saliva and a higher CA VI_ACT in both saliva and biofilm. Only saliva pH could predict the dmfs + active WSL. In biofilm, if CA VI_ACT is increased by one pixel/µg, 0.85 ± 0.28 increase is expected in the number of active WSL. Salivary pH and CA VI_ACT in saliva and biofilm had the power to predict ECC occurrence.

CONCLUSION

Changes in saliva pH and CA VI_ACT in biofilm predicted the number of lesion occurrence. Furthermore, CA VI_ACT in both saliva and biofilm can predict propensity for ECC.

Towards the development of flexible carbon nanotube–parafilm nanocomposites and their application as bioelectrodes

Soft, flexible and conductive interfaces, which can be used as electrode materials integrated with commercial electronic components and the human body for continuous monitoring of different analytes are in high demand in wearable electronics.

Combined effect of starch and sucrose on carbonic anhydrase VI activity in saliva and biofilm of children with early childhood caries. Exposure to starch and sucrose alters carbonic anhydrase VI activity in saliva and biofilm

OBJECTIVES

This study aimed to investigate whether combined exposure to starch and sucrose modifies the activity of carbonic anhydrase VI (CA VI) in saliva (Study 1) and biofilm (Study 2) of children with early childhood caries (ECC).

MATERIAL AND METHODS

For Study 1 and Study 2, respectively, 54 and 46 preschoolers aged 4 to 5 were allocated into two groups: caries-free (CF) and with ECC. Children were exposed to rinses with sucrose, starch, and sucrose plus starch solutions. CA VI activity, pH, and buffering capacity (BC) were evaluated in saliva and biofilm.

RESULTS

In Study 1, a significant reduction in saliva pH was observed after sucrose and sucrose plus starch rinses. CA VI activity was influenced by ECC independently of the type of carbohydrate to which children were exposed. CA VI activity was higher in children with ECC; however, after rinses, CA VI activity was reduced. In Study 2, biofilm pH and BC were reduced after rinses with sucrose and sucrose plus starch. CA VI activity was significantly high before rinse in ECC group when compared with CF group; however, no difference was observed between groups after rinses.

CONCLUSIONS

In saliva, exposure to starch and sucrose (isolated or combined) induced a reduction in CA VI activity in children with ECC. In biofilm, the combination of starch and sucrose did not modify CA VI activity in ECC children.

CLINICAL RELEVANCE

The responsivity of the CA VI reflects directly in important parameters related to the pH maintenance on the oral cavity.

Post-periodontal surgery propounds early repair salivary biomarkers by 1H NMR based metabolomics

INTRODUCTION

Oral microflora is a well-orchestrated and acts as a sequential defense mechanism for any infection related to oral disease. Chronic periodontitis is a disease of a microbial challenge to symbiosis and homeostasis. Periodontal surgery is the most promising cure with repair process during periodontal regeneration. It has an encouraging outcome in terms of early recovery biomarkers.

OBJECTIVE

Saliva of periodontal surgery subjects with the chronic periodontitis have been evaluated by ¹H NMR spectroscopy in search of possible early metabolic differences that could be obtained in order to see the eradication of disease which favours the symbiotic condition.

METHOD

The study employed ¹H NMR spectroscopy on 176 human saliva samples in search of distinctive differences and their spectral data were further subjected to multivariate and quantitative analysis.

RESULT

The ¹H NMR study of periodontal surgery samples shows clear demarcation and profound metabolic differences when compared with the diseased condition. Several metabolites such as lactate, ethanol, succinate, and glutamate were found to be of higher significance in periodontal surgery in contrast to chronic periodontitis subjects. The PLS-DA model of the studied group resulted in R² of 0.83 and Q² of 0.70.

CONCLUSION

Significant metabolites could be considered as early repair markers for chronic periodontitis disease as they are being restored to achieve symbiosis. The study, therefore, concluded the early recovery process of the diseased subjects with the restoration of possible metabolomic profile similar to the healthy controls.

Extremely stretchable and conductive water-repellent coatings for low-cost ultra-flexible electronics

Rapid advances in modern electronics place ever-accelerating demands on innovation towards more robust and versatile functional components. In the flexible electronics domain, novel material solutions often involve creative uses of common materials to reduce cost, while maintaining uncompromised performance. Here we combine a commercially available paraffin wax–polyolefin thermoplastic blend (elastomer matrix binder) with bulk-produced carbon nanofibres (charge percolation network for electron transport, and for imparting nanoscale roughness) to fabricate adherent thin-film composite electrodes. The simple wet-based process produces composite films capable of sustained ultra-high strain (500%) with resilient electrical performance (resistances of the order of 10¹–10² Ω sq⁻¹). The composites are also designed to be superhydrophobic for long-term corrosion protection, even maintaining extreme liquid repellency at severe strain. Comprised of inexpensive common materials applied in a single step, the present scalable approach eliminates manufacturing obstacles for commercially viable wearable electronics, flexible power storage devices and corrosion-resistant circuits.

The development of modern flexible electronics calls for new materials with extreme stretchability and high conductivity. Here, Mates et al. show a printable material made of commercially-available elastomers and carbon nanofibres, which exhibits low resistance and water-repellency at strain up to 500%.

Effect of White Cheese and Sugarless Yoghurt on Dental Plaque Acidogenicity

White cheese and sugarless yoghurt are frequently consumed traditional Turkish foods. The aim of this study was to assess their acidogenic potential when eaten alone or following a rinse with sucrose solution. Plaque pH was measured by a pH microelectrode at baseline to determine the resting plaque pH and at time intervals of 1-60 min after rinsing with 10% sucrose solution or eating the test food for 1 min. White cheese consumption for 1 min increased the plaque pH. When white cheese was eaten 5 min after rinsing with 10% sucrose solution, the plaque pH rose rapidly. After sugarless yoghurt consumption, the pH fell to a similar minimum as for sucrose after 5 min but returned to baseline levels after 30 instead of 60 min. Consumption of sugarless yoghurt after a sucrose rinse initially reduced the plaque pH further but did not affect the time taken for pH to regain baseline levels.

A role of salivary carbonic anhydrase VI in dental plaque

OBJECTIVE

Carbonic anhydrase (CA) VI is a unique secreted isozyme of CA, which catalyzes the reversible reaction CO2 +H2O<-->H+ +HCO3-. CA VI has been thought to provide a greater buffering capacity to fluids into which it is secreted. This study was performed to confirm this in saliva.

DESIGN

Nine healthy subjects participated in the study. The pH of the dental plaque from each subject was monitored after a mouth rinse with 10% sucrose with or without 10(-5)M acetazolamide, a specific inhibitor of CA. Also CA was examined in plaque by enzyme histochemistry, immunohistochemistry and Western blot analysis.

RESULTS

Though sucrose and sucrose plus inhibitor yielded Stephan curves with a similar temporal pattern, the pH values of the latter were significantly lower than those of the former. Plaque exhibited CA activity by enzyme histochemistry. Immunohistochemistry and Western analysis demonstrated that the activity was due to CA VI but not to CA I or CA II.

CONCLUSIONS

The results indicate that CA VI in saliva penetrates plaque and facilitates acid neutralization by salivary bicarbonate. Therefore, CA VI may be considered an anti-caries protein in saliva.

Developments in dental plaque pH modelling

OBJECTIVES

The objectives of this review were to give a comprehensive account of the methods used to determine dental plaque pH over the last 50 years, to review how these methods have been used in dental cariology research and to give an update as to how dental plaque pH studies might be developed in the future.

DATA

Published, referred papers and abstracts of conference proceedings in the literature were reviewed.

SOURCES

A comprehensive search of the electronic databases PubMed and Medline, was undertaken. In addition, a hand search of the Index Denticus was done to identify relevant citations before 1966.

STUDY SELECTION

Relevant published literature in peer-reviewed publications was reviewed. No additional inclusion criteria were applied.

CONCLUSIONS

This comprehensive review gives an account of the background to, history of, relative merits and demerits of, applications of and future of dental plaque pH technologies.

Chewing gum--facts and fiction: a review of gum-chewing and oral health

The world market for chewing gum is estimated to be 560,000 tons per year, representing approximately US $5 billion. Some 374 billion pieces of chewing gum are sold worldwide every year, representing 187 billion hours of gum-chewing if each piece of gum is chewed for 30 minutes. Chewing gum can thus be expected to have an influence on oral health. The labeling of sugar-substituted chewing gum as "safe for teeth" or "tooth-friendly" has been proven beneficial to the informed consumer. Such claims are allowed for products having been shown in vivo not to depress plaque pH below 5.7, neither during nor for 30 minutes after the consumption. However, various chewing gum manufacturers have recently begun to make distinct health promotion claims, suggesting, e.g., reparative action or substitution for mechanical hygiene. The aim of this critical review--covering the effects of the physical properties of chewing gum and those of different ingredients both of conventional and of functional chewing gum--is to provide a set of guidelines for the interpretation of such claims and to assist oral health care professionals in counseling patients.

Effects of lactate dehydrogenase and nicotinamide adenine dinucleotide on human dental plaque pH and acid anion concentrations

The effect of sucrose rinses supplemented with L-LDH and NAD was investigated. When LDH or NAD were added to the sucrose rinse, the pH fall was less marked than with rinsing with sucrose alone. Significant differences (p < 0.05) in mean minimum pH and cH areas were observed when sucrose rinses were supplemented with LDH, NAD or with a combination of LDH and NAD, when compared with sucrose alone. Plaque fluid concentrations of lactate and acetate significantly decreased with all rinses when compared with sucrose alone. Phosphate levels also decreased, although not significantly, when NAD was the sole supplement. No significant decreases were observed in succinate, formate or propionate concentrations. The results confirm the beneficial effect of LDH in reducing the accumulation of lactate in plaque following a sucrose rinse. The inclusion of NAD in the rinse demonstrated the role of extracellular hydrogen acceptors in the reaction. Further work is required to identify endogenous hydrogen receptors and to clarify the fate of pyruvate resulting from the oxidation of lactate before the potential role of LDH as a cariostatic agent can be fully understood.

Saliva stimulation and caries prevention

The protective role of saliva is demonstrated by the rampant caries seen in human subjects with marked salivary hypofunction, and in desalivated animals. In normal cases, however, the relationship between saliva flow and coronal or root caries experience is doubtful, and to examine the concept that stimulation of saliva might have protective effects against caries, one must look beyond a simple correlation between caries and flow rate. Protective properties of saliva which increase on stimulation include salivary clearance, buffering power, and degree of saturation with respect to tooth mineral. These benefits are maximized when saliva is stimulated after the consumption of fermentable carbohydrates, by reducing the fall in plaque pH leading to demineralization and by increasing the potential for remineralization. Plaque acid production is neutralized, and experimental lesions in enamel are remineralized, when gum is chewed to stimulate saliva after a carbohydrate intake. The pH-raising effects are more easily explained by the buffering action of the stimulated saliva than by clearance of carbohydrates. The remineralization action depends upon the presence of fluoride. These findings suggest that the protective actions of saliva can be mobilized by appropriate salivary stimulation, and that in addition to established procedures such as tooth cleaning and fluoride regimens, eating patterns which lead to saliva stimulation to increase the potential for saliva protection might be included in recommendations for caries prevention. Confirmation of this concept in clinical tests is required.

The effect of increased mastication by daily gum-chewing on salivary gland output and dental plaque acidogenicity

The effect of increased mastication on plaque metabolism and salivary gland function was determined in 11 human subjects who chewed a sugarless gum for ten minutes of each waking hour for two weeks. Prior to and at the conclusion of the gum-chewing regimen, unstimulated whole saliva and 2% citric-acid-stimulated parotid saliva were collected. Flow rates, pH, and buffer capacity were determined on all saliva samples. In addition, parotid saliva was analyzed for protein concentration and the proteins further studied by SDS-PAGE. The plaque pH response to a 10% sucrose rinse was also measured before and after the regimen. Significant increases were observed in the pH and buffer capacity of unstimulated whole saliva as were similar increases in the flow rate, pH, and buffer capacity of stimulated parotid saliva. Protein concentrations and profiles remained unaffected. In addition, the resting plaque pH and minimum plaque pH reached after a sucrose challenge were both raised significantly, with a significant reduction in the cH area. The results of this study indicate that increased masticatory effort by frequent consumption of sugar-free chewing gum over a prolonged time period resulted in a functional increase in the output of stimulated parotid saliva, as well as in increases in pH and buffer capacity of whole and parotid saliva, which may help to reduce plaque acidogenicity.

The effect of cheese on dental caries: a review of the literature

The relationship between nutrition and dental health has been a topic of interest for many years. Recently, the cariostatic properties of cheese have been the subject of intensive research. Most of these studies suggest that the use of cheese as the final food in a meal will help to reduce caries. Several mechanisms by which cheese may reduce enamel demineralization have been proposed. Chewing cheese stimulates saliva flow. The alkaline nature of saliva buffers the acids formed in plaque. There is also an increased rate of sugar clearance due to the diluting action of cheese-stimulated saliva. Research has also suggested that chewing cheese may reduce the levels of cariogenic bacteria. This may be secondary to the reduced incidence of caries as conditions within a carious lesion tend to promote the growth of these organisms. The high calcium and phosphorus content seems to be another factor in the cariostatic mechanism of cheese. Both casein and whey protein seem to be involved in the reduction of enamel demineralization. Casein phosphopeptides may also be responsible for some anticariogenicity by concentrating calcium and phosphate in plaque. An overview of the effect of milk on dental caries is also presented in this review.

Plaque fluid as a bacterial milieu

Studies of the extracellular, free concentrations of substrates, growth factors, inhibitors, and end-products of metabolism to which the intact plaque microflora is exposed in situ can assist in the understanding of factors controlling plaque pathogenicity. Information is becoming increasingly available from analysis of fluid separated by centrifugation of plaques collected at various intervals after an intra-oral pulse of dietary or experimental substrate, or different procedures or treatments having cariostatic potential. Such analytical results give more information than those obtained by analysis of aqueous or other extracts, because they yield values of substrate concentration representing those occurring at the bacterial cell surface. The largest body of information concerns extracellular levels of acid end-products of sugar catabolism in relation to food quality or sequence, and of amino acids and other products of nitrogen metabolism, in relation to studies of the detailed metabolic events of the Stephan curve, and of the demineralizing effect of the plaque environment. Areas where little information is available and which merit further study include plaque clearance of salivary and other components with anti-caries activity (e.g., antibodies, enzymes, fluorides, cations, other antimicrobials, etc.), and substrate concentrations to determine gradients for diffusion into and out of plaque.