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Table of Contents   
ORIGINAL RESEARCH  
Year : 2014  |  Volume : 25  |  Issue : 6  |  Page : 737-741
The effect of Propolis and Xylitol chewing gums on salivary Streptococcus mutans count: A clinical trial


Department of Pedodontics and Preventive Dentistry, Rajarajeswari Dental College and Hospital, Bengaluru, Karnataka, India

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Date of Submission21-Oct-2013
Date of Decision12-Nov-2013
Date of Acceptance14-Jan-2015
Date of Web Publication02-Mar-2015
 

   Abstract 

Background: Streptococcus mutans is one of the most common cariogenic microorganisms. Use of natural anticariogenic agents, such as Xylitol has been well-established in the literature. On the other hand, there is a scarcity of studies that have reported the antimicrobial potential of Propolis as an anticariogenic chewing agent; hence, the present study was designed.
Aims: To evaluate and compare the anticariogenic action of two commercial chewing gums Propolis and Xylitol on the salivary S. mutans count in a group of children from Bengaluru city.
Settings and Design: Clinical setting and experimental design.
Materials and Methods: Thirty healthy children aged 8-11 years with decayed, missing, and filled teeth (dmft)/DMFT index score ≥3 were included in the study. Before the test, unstimulated saliva was collected. Children divided into Group I and II were given Propolis and Xylitol chewing gums respectively; to chew for 15 min. Saliva samples were then collected at 15 min (just after spitting) and after 1 h. The amount of S. mutans in saliva was evaluated using a selective media (MSAB). In addition, compliance of the two chewing gums among the children was tested with a questionnaire.
Statistical Analysis Used: Student's t-test.
Results: Six samples out of 30 were excluded due to no growth. The total number of bacterial colonies was significantly reduced when compared to baseline in both the groups. Propolis gum showed statistically significant reduction in the number of colonies as compared to Xylitol. Xylitol gum was more preferred than Propolis gum by the children.
Conclusions: Propolis chewing gum can be used as an anticariogenic agent in children.

Keywords: Anticariogenic agent, Propolis, Streptococcus mutans, Xylitol chewing gum

How to cite this article:
Tulsani SG, Chikkanarasaiah N, Siddaiah SB, Krishnamurthy NH. The effect of Propolis and Xylitol chewing gums on salivary Streptococcus mutans count: A clinical trial. Indian J Dent Res 2014;25:737-41

How to cite this URL:
Tulsani SG, Chikkanarasaiah N, Siddaiah SB, Krishnamurthy NH. The effect of Propolis and Xylitol chewing gums on salivary Streptococcus mutans count: A clinical trial. Indian J Dent Res [serial online] 2014 [cited 2019 Oct 18];25:737-41. Available from: http://www.ijdr.in/text.asp?2014/25/6/737/152182
Dental caries is ubiquitous and is one of the most prevalent infectious diseases of man; its incidence is particularly high during childhood. [1]  Streptococcus mutans Scientific Name Search ost frequently associated microorganism with dental caries. [2]

The health field has always aimed to use natural products as an alternative to conventional formulations. Xylitol and Propolis, both are natural substances having antibacterial properties. Xylitol is a naturally occurring noncariogenic sugar substitute that cannot be metabolized by oral bacteria even if administered for years. [3] The use of Xylitol chewing gum, a leading anticariogenic gum in the market, has been shown to reduce caries incidence.

Propolis, on the other hand, a resinous and natural substance, which has gone unnoticed in spite of its potential uses in curing a large array of diseases, is a subject of recent dental research. Propolis is composed of resin and balsams (50-60%), pollen (5-10%), amino acids, minerals, vitamins A, B complex, the highly active biochemical substance known as bioflavonoid (vitamin P), phenols and aromatic compounds. [4] Flavonoids are well-known plant compounds, which have antibacterial, antifungal, antiviral, antioxidant, and antiinflammatory properties, thus contributing to the antibacterial action of Propolis. [5],[6] Propolis is available in the world markets in different forms as capsules, lozenges, tincture, cream and recently added to the list are mouth rinses, chewing gums and toothpastes. [5],[6],[7] Almost all the in vivo studies on Propolis have used it as an extract in terms of mouth rinse. [3],[8],[9],[10],[11],[12] Very fewer studies have studied its action as a chewing agent especially in children; in whom, chewing gum is most favored. Thus, the aim of the present study was to evaluate and compare the anticariogenic action of two commercial chewing gums Propolis and Xylitol on the salivary S. mutans count.


   Materials and methods Top


Hundred children, aged 8-11 years, from a school in South Bengaluru city were screened as a part of routine dental examination and 30 children with an age range of 8-11 (mean age of 9.13 ± 1.04) were included in the study. The inclusion criteria comprised of children recorded with a dental caries score (decayed, missing, and filled teeth (dmft)/DMFT) ≥3, those who were willing to comply with the procedures and children with written consent signed from parents. The exclusion criteria included medically compromised children, children with any systemic diseases or allergies, those with a history of taking antibiotics 3 months prior to and during the study period, children undergoing orthodontic treatment or with an intraoral prosthesis and those with presence of any intraoral soft tissue pathology.

The investigation that was carried out over the duration of 60 days had a randomized double-blind prospective design that was approved by the ethical committee of the institution. The study and intervention involved were explained in detail to the school authorities, children and the parents of the included children in the study. No modifications were made in the diet or oral hygiene measures of the children. The school authorities were however advised not to provide any food 2 h prior to the procedure. Prior to the commencement of the chewing regime, at 11.30 a.m. (which was more than 2 h after the morning breakfast); about 2 mL of unstimulated saliva samples were collected from all the children in sterile falcon tubes and were transferred immediately to the laboratory in an ice box. The saliva samples were vortexed, and serial dilutions prepared. 100 μL was inoculated on selective media for S. mutans (Mitis Salivarius Bacitracin Agar, HiMedia Laboratories, Pvt. Ltd., Mumbai, India) and incubated at 37°C for 48 h. Colony forming units were counted and recorded.

The children were then assigned with numbers from 1 to 30. They were randomly allocated into two groups, and the confounding factors were taken into consideration. The total study population consisted of 20 males and 10 females. Both the participants and the examiner were blinded. The chewing gums were wrapped in green and yellow packages, which were prepared by an assistant. The male subjects given 20 packages (10 green and 10 yellow); and the female subjects was given 10 packages (5 green and 5 yellow). Children were asked to pick the color they wanted, and their number and the color were recorded. Thus, two groups, each of 15 children (10 males and 5 females) were formed. The green group was assigned as Group I and the yellow group as Group II. Group I was given a commercially available Propolis chewing gum (Propolia, Apimab Laboratories, France, containing 6.4% Propolis) and Group II was given a commercially available Xylitol chewing gum (Happydent-Xylit® Perfette Van Melle Pvt. Ltd., India, containing 15% Xylitol). Children were asked to chew the gums for 15 min under supervision of the examiner. Saliva samples were collected at 15 min (immediately after spitting the gum) and later at 1 h. In between the time intervals, the children were not allowed to eat or drink anything. The saliva samples were transferred to the laboratory and processed. S. mutans count was evaluated and compared with the baseline values. The color codes of the gums were revealed after the results had been fed into SPSS version 16 software package (SPSS Inc; Chicago, USA).

The correlation of S. mutans count and dmft/DMFT score before intervention was evaluated using Pearson's correlation coefficient test. Student's t-test was used to compare between the groups and paired t-test was used to compare within each group at different time intervals. Normality of data was checked using Anderson-Darling test, and the data were found to be normal. In order to ascertain the preference of the chewing gums, all the children were asked to use both the chewing gums at the end of the study and were given a questionnaire to answer. Their preference was recorded based on taste acceptability. After the test, full mouth rehabilitation, followed by oral hygiene counseling was conducted for the included children.


   Results Top


Samples were collected from all the 30 children included in the study. The overall mean dmft/DMFT score was found to be 4 ± 1.14. A significant positive correlation was found between the dmft/DMFT score and the baseline S. mutans count (r = 0.7). After microbiological culture, six samples out of 30 that showed no growth and contamination were excluded from the final results. Paired t-test showed no statistical difference in the baseline S. mutans count between Group I and Group II [Table 1]. However, in both the groups there was a significant reduction in mean S. mutans count at both the time intervals (15 min and 1 h) when compared with the baseline values [Table 2] and [Table 3]. Group I (Propolis chewing gum group) showed a significant reduction in the mean S. mutans count than Group II (Xylitol chewing gum group) at both the time intervals [Table 1], [Figure 1] and [Figure 2]. A slight increase in the count was noted from 15 min to 1 h in both the groups that was not significant [Figure 3] and [Figure 4]. Out of 30 children, 75% found Xylitol chewing gum sweeter and more tasteful than Propolis chewing gum.
Figure 1: Streptococcus mutans colonies on MSAB (Group I): (a) At baseline; (b) After 15 min; (c) After 1 h

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Figure 2: Streptococcus mutans colonies on MSAB (Group II): (a) At baseline; (b) After 15 min; (c) After 1 h

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Figure 3: Box-plot showing difference in the mean Streptococcus mutans count

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Figure 4: Graph showing mean Streptococcus mutans at different time intervals

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Table 1: Comparison of mean S. mutans count between Group I and Group II at different time intervals

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Table 2: Comparison of mean S. mutans count within Propolis group at different time intervals

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Table 3: Comparison of mean S. mutans count within Xylitol group at different time intervals

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   Discussion Top


Prevention of dental caries in children is one of the hallmarks of contemporary pediatric dental practice. The concept of dentistry has recently changed from conventional dental treatment to prevention of dental caries to a large extent with the use of various novel techniques apart from the traditional ones. Since the establishment of the fact that S. mutans plays a primary role in causing dental caries, [12] specifically targeted antimicrobial agents have been researched extensively so as to achieve effective dental caries prevention. With the increased penchant for natural products, researchers are currently interested in the promising perspectives that these natural substances have to offer as alternatives for the control of dental caries in terms of antimicrobial response and lower associated risks.

The use of chewing gums as an anticariogenic agent has been well-accepted by the population as it is easy to use and does not require supervision. Chewing sugar-free gum has shown potentially beneficial effects on dental health. [13] During the past 10 years, interest has been focused on using such gums after meals and snacks. The effect of chewing gums on caries may be attributed to the stimulation and increase of salivary flow, its resultant increased buffer capacity, resulting in increased removal of bacterial substrates, which suggests an influence in the remineralization process, promoted by the regular use of chewing gums. [13]

Currently, more that 50% of chewing gums available in the market are sweetened with sugar substitutes such as sugar alcohols (polyols), the most common of which are sorbitol and Xylitol; [14] of which Xylitol has been proven to have the maximum anticariogenic activity. Xylitol is a nonfermentable sweetener that reduces the growth and metabolism of S. mutans, thus creating a less cariogenic oral environment. [15] Lately, Propolis, a natural antibiotic [16] that honeybees (Apis mellifera L.) collect from various plant species and mix with wax and other substances, [17] has attracted much attention as a useful natural substance in folk medicine to treat a variety of ailments for its antibacterial and antiinflammatory properties. According to test tube studies, Propolis has antibiotic activities that help the bee-hive block out viruses, bacteria, and other organisms, which appear to be retained in its commercial preparations. [3]

In current study, commercial preparations of the chewing gums were used as they are readily accessible to the general population. Also, the in vivo studies comparing the antimicrobial action of Propolis and Xylitol chewing gums in children are lacking. S. mutans was selected as the test organism as literature has consistently shown influence of S. mutans on caries experience in children as well as an adult population. [18],[19],[20],[21],[22] The present study also revealed a significant positive correlation between the baseline S. mutans count and the dmft/DMFT score (r = 0.7, P < 0.01), thus being in consonance with the earlier studies. [18],[19],[20],[21],[22] The age group of 8-11 years was decided, as the use of anticariogenic chewing gum is a well-adopted practice among the preadolescent and the adolescent groups. It has advantages over the other sugar chewing gums, and they find it pleasurable when bored. [23] Also, the compliance of chewing gums in prevention of caries in children can be considered better than any other form.

The two chewing gums used in this study contained Propolis 6.4% and Xylitol 15% as the primary ingredient respectively. These concentrations of both the substances have found to be optimal to exert the antibacterial action. [24],[25],[26] The other secondary ingredients in the Xylitol chewing gum and Propolis chewing gum included neem, pudina and liquorice, menthol mint aromas, green clay respectively, which are proven to have antimicrobial property thus acting in synergism with the primary agents in both the chewing gums. [27],[28],[29],[30] This study revealed a significant reduction in the S. mutans count from baseline to end of 15 min and 1 h with the use of both the Xylitol and Propolis chewing gum. Our data are consistent with earlier observations that Xylitol gum, [31],[32],[33],[34],[35] and Propolis gum [7],[8],[9],[10],[11] significantly reduce the number of S. mutans in saliva. On comparison of Group I and Group II, it was found that Propolis chewing gum group showed a statistical significant reduction in S. mutans count than the Xylitol chewing gum at all the time intervals. This difference could be partially attributed to the varying proportion of the secondary ingredients in both the chewing gums. A slight increase in the S. mutans count was found at the end of 1 h when compared to 15 min in both the groups, although not significant. This increase might have been influenced by overlapping factors, such as a delayed peak formation of colonies, together with the short period for an effective action, which may indicate using the chewing gum more than once in a day. [36],[37],[38]

Seventy-five percent of the children found the taste of the Propolis gum unacceptable, whereas Xylitol gum was accepted by almost all the children. Autio and Courts [39] evaluated the acceptance and compliance of a Xylitol chewing gum regimen by both preschool children and classroom teachers and found Xylitol gum to be well-accepted by the children. Propolis originally being a substance of bitter taste as compared to Xylitol, acceptance by children totally depends on the efficacy of the flavoring agents used in the Propolis chewing gum. An attempt to mask its taste with effective flavoring agents, without disturbing its beneficial properties, easy accessibility and better marketing strategies can increase its usage among the children. The study also provided great motivation for the children to use such preventive measures. No new caries lesions were noticed in the children at 3 months recall.

To the best of our knowledge and belief, there are very few studies comparing the anticariogenic action of the commercially available Propolis chewing gum with Xylitol chewing gum. Although this was a short term study with less sample size, a statistical significant reduction was seen in the S. mutans count after the use of commercial Propolis chewing gum. However, further long-term evaluations are recommended with a larger group to observe its effect on consistent reduction of S. mutans and assess its practical and economic feasibility.


   Conclusion Top


Propolis chewing gum showed a significant reduction in the salivary S. mutans count when compared to Xylitol gum. Propolis chewing gum can be effectively used as a caries preventive agent in children. However, the taste of the chewing gum needs to be further enhanced for its better acceptance among children.


   Acknowledgements Top


The authors would like to thank Mr. Thejasvi Venkatesmurthy from StatIntelligence Network for his statistical help.

 
   References Top

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Correspondence Address:
Sneha Girdhari Tulsani
Department of Pedodontics and Preventive Dentistry, Rajarajeswari Dental College and Hospital, Bengaluru, Karnataka
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/0970-9290.152182

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