Scientific Opinion on the substantiation of a health claim related to sugar free chewing gum and reduction of tooth demineralisation which reduces the risk of dental caries pursuant to Article 14 of Regulation (EC) No 1924/2006

A concise review of chewing gum as an anti-cariogenic agent

Chewing gum has been endorsed as a caries preventive agent by the FDI World Dental Federation, the American Dental Association, and the European Food Safety Authority. This review discusses the mechanism and provides an update of the use of chewing gum for caries prevention. Chewing gum typically consists of a water-insoluble gum base, water-soluble added ingredients, and active ingredients. It can be classified as sugar-containing or sugar-free, as well as nonmedicated or medicated. Chewing gum prevents dental caries through a range of mechanisms, including the clearance of the oral cavity, neutralization of oral acidity, inhibition of cariogenic bacterial growth, remineralization of enamel, and reduction of appetite. Recent clinical studies have evaluated the efficacy of sugar-free chewing gum for caries prevention, with most demonstrating positive results, although some studies have reported contradictory outcomes. To achieve optimal caries prevention, it is generally recommended that individuals chew sugar-free gum for five minutes after meals, three times daily.

A Systematic Review and Meta-Analysis of the Role of Sugar-Free Chewing Gum on Plaque Quantity in the Oral Cavity

Background

The aim of this systematic review of published literature was to answer the research question, “What is the difference in the level of plaque quantity, in adults and children who chew sugar-free gum (SFG), compared with those who do not chew SFG, who do not chew gum, or who use alternatives such as probiotics or fluoride varnish?”.

Methods

The systematic review [registered on PROSPERO 2018 (CRD42018094676)] included studies on adults and children with chewing of SFG as the main intervention, where “sugar” referred to monosaccharides and disaccharides. Included studies were in English and corresponded to primary research published between 1946 and 2020. The search conducted spanned all relevant databases using both Medical Subject Headings (MESH) and free text with combinations of “chewing gum,” “sugar-free,” “caries,” “xerostomia,” “periodontal disease.”

Results

Eight articles included plaque quantity as part of their outcomes. Meta-analysis showed that SFG significantly reduced plaque quantity (effect size−0.778; 95% CI−1.167 to−0.39). The correlation between the baseline and the end of study data was assumed to be 0.95 for the control and 0.65 for the SFG group. A sensitivity analysis was conducted with the pre- to post-test correlation, set at 0.95 for the SFG group. This gave an effect size of−1.098 (95% CI−1.539 to−0.656) with I² = 89.73%. When looking more specifically at xylitol gum, the results of the meta-analysis showed that it significantly reduced plaque quantity (effect size−0.743; 95% CI−1.148 to−0.338). There was a high degree of heterogeneity between studies with I² = 86.0%.

Conclusion

There is some evidence that chewing sugar-free gum, in particular xylitol SFG, reduces the quantity of plaque in the oral cavity in comparison to non SFG chewing or no chewing controls. Further research with improved design, lengthier timeframes and higher number of participants should be considered.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=94676.

Impact of Compression Force on Mechanical, Textural, Release and Chewing Perception Properties of Compressible Medicated Chewing Gums

Medicated chewing gums (MCGs) represent a beneficial platform for realizing drugs intended for dental prophylaxis and treatment. The present study aimed to investigate the impact of compression force on the mechanical, textural, release, and chewing perception characteristics of compressible MCGs with the combination of lysozyme hydrochloride (LH) and ascorbic acid (AsA). Four batches of MCGs were obtained on a laboratory single-punch tablet machine applying different forces, i.e., 5, 7, 10, and 15 kN, and evaluated by their geometrical parameters, mechanical resistance, surface and internal structure characteristics, texture profile, release behavior, and perception attributes during mastication. It was found that increasing compression force slightly affected resistance to crushing and friability of MCGs, but resulted in surface smoothing and formation of a thicker layer with highly compacted particle arrangement. According to the texture analysis, increasing compression force led to harder and more adhesive gums, indicating possible difficulties in chewing and, therefore, impairment of their consumer properties. Lower compression forces were also found to be preferable in terms of better drug release from the obtained chewing gums. The volunteers’ assessment showed that an increase of compression force led to significantly raising the initial hardness and crumbliness as well as to decreasing the rate of the integral gum mass formation during mastication, which may negatively affect perceptive sensations when using MCGs. Based on the results obtained, the optimal compressing force was selected to be 7 kN, which allows obtaining MCGs with good organoleptic, mechanical, textural, and release properties.

The economic benefits of increased sugar-free chewing gum in China: a budget impact analysis

Background

To analyze the potential cost savings in dental care associated with increased sugar-free gum (SFG) use among Chinese teenagers and adults.

Methods

The amount of SFG chewed per year and decayed, missing and filled teeth (DMFT) was collected from a cross-sectional survey to create a dose–response curve assumption. A cost analysis of dental restoration costs was carried out. A budget impact analysis was performed to model the decrease in DMFT and the subsequent cost savings for dental care. Three different scenarios for the increase in the number of SFG were calculated.

Results

The average cost savings per person in the Chinese population due to increasing SFG use ranged from 45.95 RMB (6.94 USD) per year to 67.41 RMB (10.19 USD) per year. It was estimated that 21.51–31.55 billion RMB (3.25–4.77 billion USD) could be saved annually if all SFG chewers among Chinese teenagers and adults chewed SFG regularly.

Conclusion

This study suggests that dental care costs could be significantly reduced if SFG use increased in the Chinese population.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-021-01786-8.

A systematic review and meta-analysis of the role of sugar-free chewing gum on Streptococcus mutans

Background

Preventive strategies targeting Streptococcus mutans may be effective in reducing the global burden of caries. The aim of the current systematic review of published literature was to determine the difference in level of Streptococcus mutans in adults and children who chew sugar-free gum (SFG), compared with those who did not chew gum, who chewed a control gum or received alternatives such as probiotics or fluoride varnish.

Methods

Systematic review (PROSPERO registration No. CRD42018094676) of controlled trials with adult and child participants where chewing of SFG was the main intervention. Databases searched (1 Jan 1946 to 31 August 2020): MEDLINE, EMBASE, PsycINFO, Scopus, Web of Science, Allied and Complimentary Medicine Database, Cochrane Central Register of Controlled Trials (CENTRAL), Open Grey, PROSPERO and the Cochrane library of systematic reviews. ‘Search terms included Medical Subject Headings, and free text to cover the following range of constructs: chewing gum, sugar free, oral health, caries, xerostomia, periodontal disease. Data extraction and Risk of Bias assessment was undertaken by three researchers using a modified version of the Cochrane RoB tool (version 1). Data synthesis was conducted using meta-analysis in STATA.

Results

Thirteen studies of SFG with micro-organisms as outcomes were identified. The use of SFG significantly reduced the load of Streptococcus mutans (effect size − 0.42; 95% CI − 0.60 to − 0.25) compared to all controls. In seven of the 13 studies the confidence intervals of the effect size estimate included zero, suggesting no effect of the intervention. Twelve trials used xylitol gum only as the basis of the intervention; xylitol gum significantly reduced the load of Streptococcus mutans (effect size − 0.46; 95% CI − 0.64 to − 0.28) in comparison to all controls. There was a moderate level of heterogeneity across the included studies. No adverse effects were recorded.

Conclusion

Chewing SFG reduces the load of Streptococcus mutans in the oral cavity in comparison to non-chewing controls. Considering the degree of variability in the effect and the moderate quality of the trials included, there is a need for future research exploring the use SFG as a preventive measure for reducing the cariogenic oral bacterial load.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-021-01517-z.

Oral health promotion: the economic benefits to the NHS of increased use of sugarfree gum in the UK

INTRODUCTION

The effect of sugarfree gum (SFG) on the prevention of dental caries has been established for some time. With increased constraints placed on healthcare budgets, the importance of economic considerations in decision-making about oral health interventions has increased. The aim of this study was to demonstrate the potential cost savings in dental care associated with increased levels of SFG usage.

METHODS

The analysis examined the amount of money which would hypothetically be saved if the UK 12-year-old population chewed more SFG. The number of sticks chewed per year and the caries risk reduction were modelled to create a dose response curve. The costs of tooth restoration, tooth extraction in primary care settings and under general anaesthetic were considered, and the effects of caries reduction on these costs calculated.

RESULTS

If all members of the UK 12-year-old population chewed SFG frequently (twice a day), the potential cost savings for the cohort over the course of one year were estimated to range from £1.2 to £3.3 million and if they chewed three times a day, £8.2 million could be saved each year. Sensitivity analyses of the key parameters demonstrated that cost savings would still be likely to be observed even in scenarios with less significant increases in SFG use.

CONCLUSION

This study shows that if levels of SFG usage in the teenage population in the UK could be increased, substantial cost savings might be achieved.

Comparison of the effect of two sugar-substituted chewing gums on different caries- and gingivitis-related variables: a double-blind, randomized, controlled clinical trial

OBJECTIVE

The aim of this study was to compare the effect of two sugar-substituted chewing gums besides toothbrushing on different clinical, microbiological, and biochemical caries- and gingivitis-related variables.

MATERIALS AND METHODS

The study was designed as a double-blind, randomized, controlled trial with three parallel arms. A total of 130 dental students, who volunteered after signing an informed consent, were randomly allocated to receive one of the following interventions: hexitol-sweetened gum containing casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), pentitol-sweetened gum containing no CPP-ACP, and control group with no gum. Subjects within the experimental groups chewed two gum pellets for 20 min three times a day after meals. The daily consumption level of both polyols was 6.0 g. Clinical examinations and salivary samplings were conducted at baseline and after 30 days of gum use. Pre- and post-intervention stimulated whole saliva samples were quantified for calcium/phosphate ionic concentration, total facultative bacterial load, Streptococcus mutans/Lactobacillus spp. counts, and Gram-negative percentage.

RESULTS

A statistically significant reduction in visible plaque score was displayed in the hexitol/CPP-ACP gum group after the intervention when compared with baseline, but the order of the effect was in the same order as the differences between the groups at baseline. A similar tendency was seen in both the pentitol/non-CPP-ACP gum and control groups regarding total salivary facultative bacterial load and S. mutans count, but median values of these parameters were more significantly reduced in the pentitol/non-CPP-ACP gum group in comparison with those of the control group. Alterations of salivary Lactobacillus spp. were demonstrated only in the pentitol/non-CPP-ACP gum group.

CONCLUSION

Although these findings might indicate that a 30-day protocol of daily chewing of pentitol-sweetened gum containing no CPP-ACP might have some a reducing effect on the salivary levels of facultative bacteria, S. mutans and Lactobacillus spp., there was only a marginal, if any, benefit from the chewing gums under study on some microbiological caries- and gingivitis-related variables.

CLINICAL RELEVANCE

Taking into account that for transferring results into clinically relevant conclusions the findings need to be strong and consistent, adhering to single significant differences appears not appropriate. Hence, the clinical significance of chewing gums as an adjunctive tool for daily oral care remained questionable.