Functional foods/ingredients on dental erosion

The erosive effect of pomegranate juice on enamel: An in vitro study

AIM

Dental erosion is a chemical-mechanical process that leads to the loss of dental hard tissues. This study aimed to investigate the effect of pomegranate juice on the enamel.

METHODS

Enamel blocks were randomly divided into three groups: deionized water, cola, and pomegranate juice. The blocks were immersed in the solutions four times a day for 14 days, and stored in artificial saliva for the remaining period. The surface hardness was measured on days 7 and 14. The surface structures of the demineralized blocks were observed via scanning electron microscopy (SEM), and the depth of demineralization was observed via confocal laser scanning microscopy (CLSM). The pH, calcium, and phosphorus levels of the three solutions were analyzed.

RESULTS

The microhardness values of the blocks in the pomegranate juice and cola groups decreased with the increase in the demineralization time. The blocks in the pomegranate juice group exhibited large fractures in the enamel column, whereas those in the cola group had pitted enamels with destruction of the interstitial enamel column. Compared with cola group, fluorescent penetration increased in pomegranate juice (P < 0.01). The pH of cola (2.32 ± 0.09) was lower than that of pomegranate juice (3.16 ± 0.16). Furthermore, the calcium content in pomegranate juice was significantly higher than that in cola (P < 0.01). Alternatively, the concentration of phosphorous in cola was significantly higher than that in pomegranate juice (P < 0.01).

CONCLUSION

These findings indicate that pomegranate juice can cause enamel demineralization with an erosive potential comparable to that of cola.

Film-Forming Polymers for Tooth Erosion Prevention

Different agents have been proposed to prevent the progression of acid induced dental substance losses, which are called erosive tooth wear (ETW), such as fluorides, calcium, and phosphate-based products; however, there is a need for a further increase in efficacy. Recently, the ability of polymers to interact with the tooth surface, forming acid resistant films, has come into the focus of research; nevertheless, there is still the need for a better understanding of their mode of action. Thus, this article provides an overview of the chemical structure of polymers, their mode of action, as well as the effect of their incorporation into oral care products, acid beverages, and antacid formulations, targeting the prevention of ETW. Recent evidence indicates that this may be a promising approach, however, additional studies are needed to confirm their efficacy under more relevant clinical conditions that consider salivary parameters such as flow rate, composition, and clearance. The standardization of methodological procedures such as acid challenge, treatment duration, and combination with fluorides is necessary to allow further comparisons between studies. In conclusion, film-forming polymers may be a promising cost-effective approach to prevent and control erosive demineralization of the dental hard tissue.

In vitro effect of toothpaste with low fluoride combined with sodium trimetaphosphate on dentine erosion

PURPOSE

This study sought to evaluate in vitro the effect of a dentifrice containing sodium trimetaphosphate (TMP) combined or not with low fluoride (500 ppm NaF) on dentine erosion of intrinsic origin.

METHODS

Human root dentine blocks were selected based on surface microhardness and randomly allocated into five groups (n = 12): negative control (0 ppm F; no TMP); F500 (500 ppm NaF); F1500 (1500 ppm NaF-positive control); TMP (1% TMP); and F + TMP (500 ppm NaF + 1% TMP). The blocks were submitted to erosion cycles (3 ×/day) for 3 days (0.01 M HCl, pH 1.5-30 s), treatment (1 min-1:3 p/p dentifrice/distilled water) and remineralization (artificial saliva/120 min). Dentine alterations were determined according to the percentage of microhardness loss (%HL), surface loss (SL) and surface analysis by scanning electron microscopy. The data were analyzed using one-way ANOVA (p < 0.05).

RESULTS

The values of SL and %HL in each group were, respectively: negative control (1.36 ± 0.36; 57.29 ± 14.14), F500 (1.46 ± 0.28; 65.66 ± 5.11), F1500 (1.52 ± 0.36; 61.66 ± 5.15), TMP (1.45 ± 0.45; 62.08 ± 3.83) and F + TMP (1.38 ± 0.42; 63.38 ± 6.47). There was no statistically significant difference in all the parameters (p = 0.873 and p = 0.152).

CONCLUSION

The dentifrices containing TMP combined or not with fluoride were not able to prevent dentine erosion.

High-resolution taxonomic examination of the oral microbiome after oil pulling with standardized sunflower seed oil and healthy participants: a pilot study

OBJECTIVES

We aimed at the high-resolution examination of the oral microbiome depending on oil pulling, compared it with saline pulling, and analyzed whether the method is capable of reducing the overall microbial burden of the oral cavity.

MATERIALS AND METHODS

The study was a cohort study with three healthy subjects. Oil pulling samples, saline pulling samples, and saliva samples were microscoped and cultured under microaerophilic and anaerobic conditions; colony-forming units were counted; and cultivated bacteria were identified employing MALDI-TOF MS. The oral microbiomes (saliva) and the microbiota incorporated in oil and saline pulling samples were determined in toto by using 16S rDNA next-generation sequencing (NGS) and bioinformatics.

RESULTS

Microscopy revealed that oral epithelial cells are ensheathed with distinct oil droplets during oil pulling. Oil pulling induced a higher production of saliva and the oil/saliva emulsion contained more bacteria than saline pulling samples. Oil pulling resulted in a significant and transient reduction of the overall microbial burden in comparison to saliva examined prior to and after pulling. Both oil and saline pulling samples mirrored the individual oral microbiomes in saliva.

CONCLUSIONS

Within the limitations of this pilot study, it might be concluded that oil pulling is able to reduce the overall microbial burden of the oral cavity transiently and the microbiota in oil pulling samples are representative to the oral microbiome.

CLINICAL RELEVANCE

Within the limitations of this pilot study, it might be concluded that oil pulling can be considered as an enlargement of standard oral hygiene techniques since it has the characteristic of an oral massage, enwrapping epithelial cells carrying bacteria in oil vesicles and reaching almost all unique habitats in oral cavity.

Factors Associated with Noncarious Cervical Lesions in Different Age Ranges: A Cross-sectional Study

OBJECTIVES

 Understanding the possible risk factors of noncarious cervical lesion (NCCL) is important for prevention and clinical management of the condition. The aim of this study was to investigate the factors associated with the prevalence of NCCL among adolescents, adults, and elderly people.

MATERIALS AND METHODS

 A cross-sectional study involving 501 participants aged 15 years or older was conducted. Participants were examined to assess the number of natural teeth and the prevalence and severity of NCCL by calibrated examiners. Data on age, gender, harmful toothbrushing habits, and acidogenic diet were collected through individual interviews. Multivariate Poisson's regression models were used to evaluate the association between the independent variables and the prevalence of NCCL according to the three age groups: 15 to 39, 40 to 64, and 65 years or older. RESULTS : The prevalence of NCCL among participants was 62.5% (95% confidence interval: 58.2-66.7). Among 15- to 39-year-old participants, the mean of NCCL was higher in males, those with lower number of teeth and acidogenic diet intake. Males aged 40 to 64 years and those with harmful brushing habits were more likely to present higher mean of NCCL. Elderly people with harmful toothbrushing habits had a greater mean of NCCL.

CONCLUSION

 Demographic (age and gender), clinical (number of teeth), and behavioral characteristics (harmful brushing habits and acidogenic diet) were meaningful factors associated with NCCL severity. The above-mentioned relationships varied between age groups.

Re-evaluation of sulphuric acid and its sodium, potassium, calcium and ammonium salts (E 513, 514 (i), 514 (ii), 515 (i), 515 (ii), 516 and 517) as food additive

The Panel on Food Additives and Flavourings (FAF) provided a scientific opinion re-evaluating the safety of sulphuric acid (E 513) and its sodium (E 514), potassium (E 515), calcium (E 516) and ammonium (E 517) salts when used as a food additive. The Panel considered that adequate exposure and toxicity data were available. Sulphuric acid and its sodium, potassium, calcium and ammonium salts (E 513, E 514, E 515, E 516, E 517) are authorised food additives in the EU, in accordance with Annex II and Annex III to Regulation (EC) No 1333/2008. In the refined estimated exposure non brand-loyal scenario, mean exposure ranged from 0.4 mg sulphate/kg body weight (bw) per day in infants to 35 mg sulphate/kg bw per day in toddlers. The high percentile of exposure ranged from 3 mg sulphate/kg bw per day in adolescents to 68 mg sulphate/kg bw per day in toddlers. The Panel considered sulphates of low acute toxicity and there is no concern with respect to genotoxicity and carcinogenicity. The Panel noted that the exposure to sulphates at mean and 95th percentile in the non brand-loyal scenario as well as in the other scenarios, is far below the 300 mg/kg a dose that induced laxative effect in humans. Based on the toxicological database available, the Panel concluded that the exposure to sulphuric acid (E 513), sodium sulphate (E 514), potassium sulphates (E 515), calcium sulphate (E 516) and ammonium sulphate (E 517) does not raise a safety concern at the reported uses and use levels and there is no need for a numerical acceptable daily intake (ADI).

Feasibility and development of a cariogenic diet scale for epidemiological research

BACKGROUND

Diet cariogenicity plays a major role as both a protective and risk factor in the development of early childhood caries (ECC).

AIM

Develop a scale measuring the cariogenicity of foods and beverages and employ it to describe the cariogenicity of young children's diets and predict dental caries outcomes.

DESIGN

Scores of cariogenicity and consumption frequency were applied to food frequency questionnaire (FFQ) collected from an Australian children's cohort study with three time-points of data. One-way ANOVA, with post hoc Tukey test compared mean cariogenic scale measured at 18 months between the subsample of children with caries classification at age 5 years.

RESULTS

At 6 months, children's mean cariogenic score was 10.05, increasing to 34.18 at 12 and 50.00 at 18 months. Mean cariogenic scale score at 18 months was significantly higher in children with advanced disease at 5 years (mean scale score: 59.0 ± 15.9) compared to those that were healthy (mean score 47.7 ± 17.5, P = 0.007) or had mild-moderate disease (mean score 48.2 ± 17.3, P = 0.008).

CONCLUSIONS

The cariogenic diet scale provides a useful indication of the increasing cariogenicity of children's diets with age and highlights the incorporation of discretionary choice foods and beverages into the diets of young children much earlier than nutritionally recommended.

Eating disorder risk behavior and dental implications among adolescents

OBJECTIVE

To compare the occurrence of tooth erosion (TE) and dental caries (DC) in adolescents with and without risk behavior for eating disorders (EDs).

METHOD

A controlled cross-sectional study involving 1,203 randomly selected female students aged 15-18 years was conducted in Brazil. Risk behavior for EDs was evaluated through the Bulimic Investigatory Test of Edinburgh and dental examinations were performed.

RESULTS

The prevalence of risk behavior for EDs was 6%. Twenty adolescents (1.7%) were identified with severe risk behavior for EDs and matched to 80 adolescents without such risk. Among the severe risk group, 45% of adolescents were affected by TE and 80% by DC compared with 8.8 and 51.3%, respectively, in the matched group. Adolescents with severe risk had higher chances for TE (OR = 10.04; 95% CI = 2.5-39.4).

DISCUSSION

In this study, a severe risk behavior for EDs was significantly associated with TE, but not with DC.

Optimization of CDT-1 and XYL1 expression for balanced co-production of ethanol and xylitol from cellobiose and xylose by engineered Saccharomyces cerevisiae

Production of ethanol and xylitol from lignocellulosic hydrolysates is an alternative to the traditional production of ethanol in utilizing biomass. However, the conversion efficiency of xylose to xylitol is restricted by glucose repression, causing a low xylitol titer. To this end, we cloned genes CDT-1 (encoding a cellodextrin transporter) and gh1-1 (encoding an intracellular β-glucosidase) from Neurospora crassa and XYL1 (encoding a xylose reductase that converts xylose into xylitol) from Scheffersomyces stipitis into Saccharomyces cerevisiae, enabling simultaneous production of ethanol and xylitol from a mixture of cellobiose and xylose (main components of lignocellulosic hydrolysates). We further optimized the expression levels of CDT-1 and XYL1 by manipulating their promoters and copy-numbers, and constructed an engineered S. cerevisiae strain (carrying one copy of PGK1p-CDT1 and two copies of TDH3p-XYL1), which showed an 85.7% increase in xylitol production from the mixture of cellobiose and xylose than that from the mixture of glucose and xylose. Thus, we achieved a balanced co-fermentation of cellobiose (0.165 g/L/h) and xylose (0.162 g/L/h) at similar rates to co-produce ethanol (0.36 g/g) and xylitol (1.00 g/g).