Effect of xylitol varnishes on enamel remineralization of immature teeth: in vitro and in situ studies

BACKGROUND

We evaluated the efficacy of xylitol varnishes on the remineralization of newly erupted permanent and deciduous teeth in vitro and in situ. Human enamel specimens were randomly allocated to 8 groups (n = 15/group). Artificial caries lesions were produced and enamel alterations were quantified by surface/subsurface hardness and transverse microradiography. The blocks were then treated with the following varnishes: DuraphatTM; 20 wt% xylitol (146 μm) varnish; 20 wt% milled xylitol (80 μm) varnish, and placebo varnish, and removed after 6 h of immersion in artificial saliva. The blocks were subjected to pH-cycles for 8 days.

CONCLUSIONS

fifteen subjects wore palatal appliances containing four pre-demineralized and treated enamel specimens, for 5 days. Data were statistically analyzed by ANOVA/Tukey and Kruskal-Wallis/Tukey's test (p < 0.05). The %SHR in both studies was significantly increased by xylitol and Duraphat™ varnishes when compared to placebo. Considering subsurface remineralization, only the xylitol varnishes were able to significantly reduce the enamel lesion. Xylitol varnishes can be promising alternatives to promote enamel remineralization of newly erupted permanent and deciduous teeth.

Plaque Removal Efficiency of Chewable Toothbrushes among 10-12-yearold Children: A Randomized Control Trial

Aim and Objectives

Toothbrushing is one of the most important factors in controlling plaque accumulation and dental caries. There are vast varieties of toothbrushes available in the market. This study was designed to evaluate the effectiveness of novel chewable toothbrushes as compared to manual toothbrushes in plaque removal among 10-12-year-old children.

Materials and Methods

This randomized controlled trial was conducted on 40 healthy children aged between 10 and 12 years of age who were randomly assigned to either of the groups: Group I--Chewable Toothbrushes and Group II--Manual Toothbrushes. Following oral prophylaxis, baseline records of oral hygiene indices (Simplified oral hygiene index (OHI-S) in indexed teeth and Turesky modification of Quigley Hein plaque index (TMQHI) were taken. Baseline Saliva samples were collected and sent for Streptococcus mutans counts. Children were then instructed to use their respective toothbrush twice daily for a week. Oral hygiene indices and S. mutans counts were repeated after 1 week.

Results

Differences in pre-brushing and post-brushing plaque scores and salivary S. mutans counts were statistically significant when compared using paired-sample t test and independent-sample t test. There was a significant reduction in salivary S. mutans counts after using both chewable and manual toothbrushes. However, there was no statistically significant difference between the two groups (P = 0.08).

Conclusion

Chewable toothbrushes are equally effective in plaque control when compared to manual toothbrushes. These can be a reliable alternative for children who lack manual dexterity.

Oral microbial biofilms: an update

Human oral cavity (mouth) hosts a complex microbiome consisting of bacteria, archaea, protozoa, fungi and viruses. These bacteria are responsible for two common diseases of the human mouth including periodontal (gum) and dental caries (tooth decay). Dental caries is caused by plaques, which are a community of microorganisms in biofilm format. Genetic and peripheral factors lead to variations in the oral microbiome. It has known that, in commensalism and coexistence between microorganisms and the host, homeostasis in the oral microbiome is preserved. Nonetheless, under some conditions, a parasitic relationship dominates the existing situation and the rise of cariogenic microorganisms results in dental caries. Utilizing advanced molecular biology techniques, new cariogenic microorganisms species have been discovered. The oral microbiome of each person is quite distinct. Consequently, commonly taken measures for disease prevention cannot be exactly the same for other individuals. The chance for developing tooth decay in individuals is dependent on factors such as immune system and oral microbiome which itself is affected by the environmental and genetic determinants. Early detection of dental caries, assessment of risk factors and designing personalized measure let dentists control the disease and obtain desired results. It is necessary for a dentist to consider dental caries as a result of a biological process to be targeted than treating the consequences of decay cavities. In this research, we critically review the literature and discuss the role of microbial biofilms in dental caries.

Prevention of dental caries: A review of effective treatments

BACKGROUND

The objective of this study is to review medical and non medical treatments for prevention of caries.

MATERIAL AND METHODS

A comprehensive literature search of the most relevant and updated published studies from 01/01/2002 through December 2015 in PubMed/MEDLINE, Embase and Scopus databases regarding the efficacy of strategies and treatments aiming to prevent the development of caries was performed selecting papers on the basis of the Evidence-based Medicine Criteria.

RESULTS

We identified thirty systematic reviews on prevention of caries. Analyzing the data the retrieved literature, performance of prevention treatments seems to be high.

CONCLUSIONS

Prevention treatments may have a relevant impact on the avoiding the development of caries planning. Key words:Dental caries, prevention, fluoride.

Impact of an anticaries mouthrinse on in vitro remineralization and microbial control

Objective. The objective of this research was to evaluate the caries control potential of a new fluoride mouthrinse that also contained antimicrobial agents and a biofilm disrupting agent using different in vitro models. Methods. Four in vitro studies were conducted to assess the performance of this three pronged approach to caries control: (1) traditional enamel fluoride uptake, (2) surface microhardness study using pH cycling model and subsequent fluoride uptake, (3) a salivary biofilm flow-through study to determine the anti-microbial activity, and (4) a single species biofilm model measuring effect on biofilm matrix disruption. Results. The data showed that a LISTERINE rinse with fluoride, essential oils and xylitol was superior in promoting enamel fluoride uptake and in enhancing antimicrobial activity over traditional commercially available fluoridated products. An increase of the surface microhardness was observed when the LISTERINE rinse was used in combination with fluoridated toothpaste versus the fluoridated toothpaste alone. Finally, it was demonstrated that xylitol solutions disrupted and reduced the biovolume of biofilm matrix of mature Streptococcus mutans. Conclusion. These in vitro studies demonstrated that a fluoride mouthrinse with antimicrobial agent and biofilm matrix disrupting agent provided multifaceted and enhanced anti-caries efficacy by promoting remineralization, reducing acidogenic bacteria and disrupting biofilm matrix.

Visual scoring of non cavitated caries lesions and clinical trial efficiency, testing xylitol in caries-active adults

OBJECTIVES

To better understand the effectiveness of xylitol in caries prevention in adults and to attempt improved clinical trial efficiency.

METHODS

As part of the Xylitol for Adult Caries Trial (X-ACT), non cavitated and cavitated caries lesions were assessed in subjects who were experiencing the disease. The trial was a test of the effectiveness of 5 g/day of xylitol, consumed by dissolving in the mouth five 1 g lozenges spaced across each day, compared with a sucralose placebo. For this analysis, seeking trial efficiency, 538 subjects aged 21-80, with complete data for four dental examinations, were selected from the 691 randomized into the 3-year trial, conducted at three sites. Acceptable inter- and intra-examiner reliability before and during the trial was quantified using the kappa statistic.

RESULTS

The mean annualized noncavitated plus cavitated lesion transition scores in coronal and root surfaces, from sound to carious favoured xylitol over placebo, during the three cumulative periods of 12, 24, and 33 months, but these clinically and statistically nonsignificant differences declined in magnitude over time. Restricting the present assessment to those subjects with a higher baseline lifetime caries experience showed possible but inconsistent benefit.

CONCLUSIONS

There was no clear and clinically relevant preventive effect of xylitol on caries in adults with adequate fluoride exposure when non cavitated plus cavitated lesions were assessed. This conformed to the X-ACT trial result assessing cavitated lesions. Including non cavitated lesion assessment in this full-scale, placebo-controlled, multisite, randomized, double-blinded clinical trial in adults experiencing dental caries did not achieve added trial efficiency or demonstrate practical benefit of xylitol.

TRIAL REGISTRATION

ClinicalTrials.Gov NCT00393055.

Tooth-surface-specific effects of xylitol: randomized trial results

The Xylitol for Adult Caries Trial was a three-year, double-blind, multi-center, randomized clinical trial that evaluated the effectiveness of xylitol vs. placebo lozenges in the prevention of dental caries in caries-active adults. The purpose of this secondary analysis was to investigate whether xylitol lozenges had a differential effect on cumulative caries increments on different tooth surfaces. Participants (ages 21-80 yrs) with at least one follow-up visit (n = 620) were examined at baseline, 12, 24, and 33 months. Negative binomial and zero-inflated negative binomial regression models were used to estimate incidence rate ratios (IRR) for xylitol's differential effect on cumulative caries increments on root and coronal surfaces and, among coronal surfaces, on smooth (buccal and lingual), occlusal, and proximal surfaces. Participants in the xylitol arm developed 40% fewer root caries lesions (0.23 D2FS/year) than those in the placebo arm (0.38 D2FS/year; IRR = 0.60; 95% CI [0.44, 0.81]; p < .001). There was no statistically significant difference between xylitol and control participants in the incidence of smooth-surface caries (p = .100), occlusal-surface caries (p = .408), or proximal-surface caries (p = .159). Among these caries-active adults, xylitol appears to have a caries-preventive effect on root surfaces (ClinicalTrials.gov NCT00393055).

Are we ready for definitive clinical guidelines on xylitol/polyol use?

In the past decades, numerous studies have looked at the anticaries effects of polyols, particularly xylitol, and a great many studies have focused on xylitol's antimicrobial properties. Researched vehicles have mostly included chewing gums, followed by lozenges/candies, toothpastes, and others (e.g., syrup). Good evidence supports the claims that xylitol is non-cariogenic and has a dose-/frequency-dependent antimicrobial effect on dental plaque/mutans streptococci, and that polyol use is very safe. However, interpretation of caries data has been controversial, due in part to variability in study designs, formulations/dosages tested, and outcomes reported (e.g., many caries studies have a "no gum" control, limiting the interpretation of the polyol's benefit; few studies have compared different polyols side-by-side, or in adults). Even when the level/strength of high-quality anticaries evidence is still limited, most recent systematic reviews have consistently concluded that the habitual use of sucrose-free xylitol or polyol-combination chewing gum/ lozenges is an effective adjunct in coronal caries prevention. Consequently, many health organizations worldwide are supporting this recommendation for at-risk populations. However, most experts agree that well-designed, placebo-controlled randomized clinical trials (RCTs) (focusing on efficacy, feasibility, adherence, dosage, vehicle, synergism with other preventive strategies, and cost) are still needed in target populations worldwide to reach definitive caries-preventive/therapeutic recommendations.

Mutans streptococci and caries prevalence in children after early maternal caries prevention: a follow-up at 19 years of age

AIM

The efficacy of early maternal caries prevention was evaluated. Furthermore, the difference between children colonised with mutans streptococci (MS) at an early or late stage with regard to the prevalence of carious lesions was determined.

METHODS

The children of first-time mothers selected on the basis of high salivary levels of MS for participation in a caries prevention programme were recalled at the age of 19 years. They were examined for salivary MS, lesion prevalence (decayed and filled surfaces, DFS) and MS in plaque from 12 selected proximal surfaces.

RESULTS

The recall rate was 70% for the children of both the high-control and interventional groups. All high-control children and 67% of the interventional children were colonised by MS. All the children with non-detectable MS in saliva were also negative in all plaque samples. No statistically significant difference was found between the groups in terms of DFS, although more interventional children were caries free than in the control group. Early-colonised children, irrespective of group identity, had higher salivary MS levels and DFS than later MS-colonised children.

CONCLUSION

The results indicate that it is possible to remain negative for MS into adulthood if non-colonised at an early age and this affects the development of carious lesions. Strategies for the prevention of dental caries in early childhood should, therefore, include measures to prevent or delay early colonisation by cariogenic bacteria.