Effect of green tea, ginger plus green tea, and chlorhexidine mouthwash on plaque-induced gingivitis: A randomized clinical trial.

BACKGROUND: Dental plaque, a microbial biofilm, is the primary etiological factor leading to the initiation of gingivitis and dental caries. It is therefore important to prevent it by taking effective plaque control measures. This research aimed at comparing the anti-plaque and anti-gingivitis effects of green tea (GT), GT plus ginger (GT + G), and chlorhexidine mouthwash (CHX) in children.
MATERIALS AND METHODS: This was a randomized clinical trial, with a sample size of 60 children between the age group of 10-14 years with plaque and gingivitis. They were randomly allocated in three different groups, depending upon the mouthwash used: Group A (GT mouthwash), Group B (GT plus ginger mouthwash), and Group C (CHX mouthwash). Plaque index and gingival index were recorded at baseline, then at interval of 15 days and 30 days after using mouthwash.
RESULTS: The mean gingival score and plaque showed a significant reduction from the baseline among all the three groups when compared with subsequent recall visits (15 days after using mouth-rinse and 30 days after using mouthwash) with P < 0.05.
CONCLUSION: It can be concluded that the results of all three groups are comparable and hence herbal mouthwash can be used effectively as an alternative to CHX and as an adjunct to mechanical plaque control. Copyright:

INTRODUCTION

In spite of many significant developments in the field of dentistry, oral diseases are considered to be a major public health concern.[1] Among all oral diseases, gingivitis and dental caries are the most prevalent in the world.[2] Dental plaque, a microbial biofilm, is the primary etiological factor leading to the initiation of gingivitis and dental caries. It is therefore important to prevent the formation and accumulation of plaque on the tooth surface by taking effective plaque control measures.[3]

Oral hygiene aids such as toothbrush and dental floss are widely used for the removal of mechanical plaques. However, this method lacks complete and efficient removal of plaque, especially from the interproximal areas of the teeth.[45] This can be attributed to poor manual dexterity and lack of motivation, especially among children.[6] Bacteria colonizing on soft tissues also serve as a major source of micro-organisms on the tooth surface. Various chemical agents are introduced as an adjunctive to mechanical plaque control measures to overcome these limitations and to achieve complete plaque removal.[7] These are available in various formulations, such as mouthwashes, tablets, and chips.

Chlorhexidine (CHX) mouthwash is considered to be the most potent and “Gold Standard” antimicrobial agent among the various chemotherapeutic agents. It is a broad-spectrum antimicrobial agent with low toxicity and has a substantivity of 8–10 h. Mouth rinse with concentrations of 0.12% and 0.2% CHX has shown an effective reduction in plaque and gingivitis. However, the long-term use of CHX is associated with some adverse effects, such as tooth staining, burning sensation, and altered taste, which reduces patient compliance. The search for new chemical agents with improved patient compliance and minimal adverse effects continues.[89]

In last few years, the use of plant extracts in alternative medicine has evolved widely. Various herbal products, including mouth wash and toothpaste, are now available and have shown to possess beneficial effect on oral health.[7]

Green tea (GT) obtained from the extracts of a small plant Camelia sinesis is the most common beverage consumed all over the world. It is rich in flavonoids such as catechins and various other polyphenols that contributes to its antioxidant and anti-inflammatory properties. Epicatechin (EC) gallate, EC, epigallocatechin (EGC), and EGC gallate are major catechins present in GT. GT consumption is also associated with lower incidences of diabetes, cardiovascular disease, and obesity. Moreover, its anti-bacterial property aids in the reduction of bacterial colonization and thereby prevents oral diseases such as gingivitis, periodontal diseases, dental caries, and malodour.[10]

In addition to GT, the therapeutic use of ginger is well-known since centuries. Ginger, scientifically named Zingiber officinale roscoe, contains phenolic compounds such as gingerol and shogaol, hydrocarbons, and oleoresins. These compounds contribute to its anti-inflammatory, anti-bacterial, and anti-oxidant property and help to combat with oral micro-organisms, thereby preventing oral diseases.[11]

Hence, the present study aimed to compare the anti-plaque and anti-gingivitis effects of three mouthwashes containing GT, GT plus ginger (GT + G), and CHX mouthwash in 10–14 years' old children.

MATERIALS AND METHODS

A double-blinded, randomized clinical study was planned in accordance with Consolidated Standards of Reporting Trials [Figure 1] checklist after necessary approval by the Institutional Ethical Committee (SVIEC/ON/Dent/RP/16033) following the World Medical Association Declaration of Helsinki: Ethical Principles for Medical Research Involving Human Subjects. Participants and their parents were explained about the study, and a prior written informed consent was obtained. The trial was registered with Clinical Trial Registry of India (CTRI No: 2018/05/014002)

Figure 1

Consolidated standards of reporting trials flow diagram. n – number of participants

Sixty participants visiting the Department of Pediatric and Preventive Dentistry (M = 29 and F = 31) between the age group of 10–14 years were selected on the basis of inclusion and exclusion criteria. Patients and their parents were informed about the study, and those who signed the informed consent were included in the study. Patients with normal occlusion and absence of restorations or any appliances with clinical features of gingivitis (Gingival Index Loe and Sillness, 1963 Grade 1 and above) and presence of dental plaque (Plaque Index Sillness and Loe, 1964 Grade 1 and above) were included in the study. Medically compromised children and those requiring special health care needs or children having a history of prolonged use of medications were excluded from the study. Furthermore, children who had used any type of antibacterial mouthwash 4 weeks before the study and those having history of known allergy to ginger, GT or CHX were excluded from the study. After thorough clinical examination, the participants were enrolled for the study, and allocation was done randomly using computerized randomization into three groups with twenty participants each.

These groups were as follows:

Group A (20) – GT mouthwash

Group B (20) – GT plus ginger mouthwash (GT + G)

Group C (20) – CHX mouthwash.

Green-tea and GT with Ginger mouthwash were prepared in Department of Pharmacy using filtration method. GT mouthwash was manually prepared by soaking 100 g of GT leaves in 500 ml of methanol for 48 h. Afterwards the solution formed was passed through a strainer and transferred to a plate. The plates were held for 3–4 days at usual laboratory temperature, and then, the extract crystal powder was scraped off the plates. Finally, 5% GT mouthwash (0.5 g extract in 100 ml distilled water) was prepared. Similarly, GT and ginger mouthwash were prepared using 50% GT leaves and 50% ginger extract. These techniques were used to prepare required volume of mouthwashes and poured in dispensing bottles.[12] Commercially available 0.2% alcohol-free CHX mouthwash was used for participants in Group 3 as positive control.

Both of the herbal mouthwashes were tested for 1 month regarding its stability, storage, and preservative properties. After testing each of them, mouthwash was prepared and distributed to the children.

All three mouthwashes were dispensed in similar bottles and coded as A, B, and C. A blinded observer, unaware of the mouthwash contents, randomly distributed the mouthwash bottles among the children to avoid bias. Twenty bottles containing GT mouthwash, 20 containing GT plus ginger mouthwash, and rest 20 bottles containing CHX mouthwash were distributed. Participants in the study were also blinded as to which mouthwash they have received.

On participants' first visit, baseline score of gingivitis and plaque was recorded using gingival index (Loe and Sillness, 1963) and plaque index (Sillness and Loe, 1964), respectively. All the participants were then trained about the use of mouthwash.[13] Furthermore, oral hygiene instructions and modified bass technique for tooth brushing were taught. The participants were instructed to use the mouth rinse twice a day.

Participants were recalled again after 15 days and 1-month interval, and the indices were recorded.

Statistical analysis

Data collected were entered and analyzed using the SPSS software (IBM Corp. Released 2012. IBM SPSS Statistics for Windows, Version 21.0. Armonk, NY: IBM Corp). Descriptive and inferential statistical analysis was carried out in the present study. Multivariant test and Friedman rank test were used for inter-group comparison. The results were considered statistically significant at P ≤ 0.05

RESULTS

A total of 60 participants were randomly divided into three groups. Among 20 participants in each group, 9 (45%) in Group A, 13 (65%) in Group B, and 9 (45%) in Group C were males, respectively.

The mean values of gingival score and plaque score are given in Tables 1 and 2, respectively. The mean gingival score showed a significant reduction from the baseline among all the three groups when compared with subsequent recall visits (15 days after using mouthwash and 30 days after using mouthwash) with P < 0.05. The gingival scores among all three groups were compared using multivariant test (Wilks lambda) at each interval. The gingival score was lowest in Group B (GT + Ginger mouth-rinse), followed by Group A (GT group) and Group C (CHX group) and was highly significant on intragroup comparison with probability value < 0.05.

Table 1

Comparison of Gingival Index Score for Group A: Green-tea, Group B: Green-tea plus ginger and Group C Chlorhexidine at different time-intervals

Group	Mean±SD			P*			Multivariant test (Wilks Lambda)
	Baseline (1)	After 15 days (2)	After 30 Days (3)	1-2	1-3	2-3	Wilks Lambda	P*
Group A (GT)	1.94±0.32	1.69±0.35	1.43±0.35	0.00	0.00	0.00	0.30	0.000
Group B (GT+G)	1.99±0.29	1.71±0.31	1.22±0.29	0.00	0.00	0.00	0.19	0.000
Group C (CHX)	1.87±0.35	1.60±0.32	1.36±032	0.00	0.00	0.00	0.39	0.000

*P≤0.05 - MANOVA test. 1-2 - Comparison baseline score - after 15 days; 1-3 - Comparison between baseline score - after 30 days; 2-3 - Comparison between after 15 days - after 30 days. SD - Standard deviation; GT - Green-tea; GT+G - Green-tea plus ginger; CHX - Chlorhexidine; P - Probability value

Table 2

Comparison of plaque index score for Group A: Green-tea, Group B: Green-tea plus ginger, and Group C Chlorhexidine at different time intervals

Group	Mean±SD			P*			Multivariant test (Wilks Lambda)
	Baseline (1)	After 15 days (2)	After 30 days (3)	1-2	1-3	2-3	Wilks Lambda	P*
Group A (GT)	1.90±0.51	1.61±0.52	1.19±0.49	0.02	0.00	0.047	0.21	0.000
Group B (GT+G)	1.76±0.55	1.35±0.56	0.89±0.38	0.03	0.00	0.00	0.10	0.000
Group C (CHX)	1.80±0.56	1.56±0.57	1.29±0.53	0.08	0.00	0.05	0.36	0.000

*P≤0.05 - MANOVA test. 1-2 - Comparison between baseline score - after 15 days; 1-3 - Comparison between baseline score - after 30 days; 2-3 - Comparison between after 15 days - after 30 days. SD - Standard deviation; GT - Green-tea; GT+G - Green-tea plus ginger; CHX - Chlorhexidine; P - Probability value

The mean plaque showed a significant reduction from the baseline among all the three groups when compared with subsequent recall visits (15 days after using mouthwash and 30 days after using mouthwash) with P < 0.05. The plaque score among all three groups were compared using multivariant test (Wilks lambda) at each interval. The plaque score was lowest in Group B (GT + Ginger mouth-rinse), followed by Group A (GT group) and Group C (CHX group) and was highly significant on intragroup comparison with probability value < 0.05.

The gingival interpretation score based on severity of inflammation in participants of all the three groups is represented in Table 3. All the three groups showed a significant reduction in the inflammation of gingiva in the subsequent recall visits after using mouth-rinse when compared to the baseline scores.

Table 3

Gingival score interpretation for Group A: Green-tea, Group B: Green-tea plus Ginger and Group C Chlorhexidine at baseline and after 15- and 30-days interval

Group	Severity	Baseline, n (%)	After 15 days, n (%)	After 30 days, n (%)
Group A (GT)	Mild	0	0	2 (10)
	Moderate	15 (75)	17 (85)	16 (80)
	Severe	5 (25)	3 (15)	2 (10)
Group B (GT+G)	Mild	0	0	8 (40)
	Moderate	14 (70)	17 (85)	12 (60)
	Severe	6 (30)	3 (15)	0
Group C (CHX)	Mild	1 (5)	1 (5)	3 (15)
	Moderate	15 (75)	17 (85)	17 (85)
	Severe	4 (20)	2 (10)	0

n - Number of participants; GT - Green-tea; GT+G - Green-tea plus ginger; CHX - Chlorhexidine

Friedman's ranking test was applied for intergroup comparison which was found to be significant (P < 0.05). Among all the three groups, group B showed better effect in reduction of gingival inflammation and bleeding (mean rank of 1.4) followed by group C (1.75) and group A (1.8) [Table 4]

Table 4

Friedman’s ranking test based on gingival score interpretation for Group A: Green-tea, Group B: Greentea plus ginger, and Group C Chlorhexidine at baseline and after 15- and 30-days interval

Group	Rank at baseline	Rank after 15 days	Rank after 30 days	P*
Group A (GT)	2.18	2.03	1.8	0.02
Group B (GT+G)	2.4	2.2	1.4	0.000
Group C (CHX)	2.2	2.05	1.75	0.009

*P≤0.05: Chi-square test. GT - Green-tea; GT+G - Green-tea plus ginger; CHX - Chlorhexidine; P - Probability value

The plaque interpretation score based on oral hygiene status of participants of all the three groups is given in Table 5. All the three groups showed a significant reduction in amount of plaque when compared to the baseline scores.

Table 5

Plaque score interpretation Group A: Greentea, Group B: Green-tea plus ginger and Group C Chlorhexidine at baseline and after 15- and 30-days interval

Group	Severity	Baseline, n (%)	After 15 days, n (%)	After 30 days, n (%)
Group A (GT)	Poor	11 (55)	4 (20)	2 (10)
	Fair	9 (45)	12 (60)	7 (35)
	Good	0 (	4 (20)	11 (55)
Group B (GT+G)	Poor	6 (30)	2 (10)	0 (
	Fair	14 (70)	13 (65)	2 (10)
	Good	0 (	5 (25)	18 (90)
Group C (CHX)	Poor	8 (40)	5 (25)	1 (5)
	Fair	12 (60)	12 (60)	10 (50)
	Good	0 (	3 (15)	9 (45)

GT - Green-tea; GT+G - Green-tea plus ginger; CHX - Chlorhexidine; n - Number of participants

Friedman's ranking test was applied for intergroup comparison which was found to be significant (P < 0.05). Among all the three groups, group B showed better effect for reduction in amount of plaque (mean rank of 2.85) followed by Group A (2.68) and Group C (2.58) (P < 0.05) [Table 6].

Table 6

Friedman’s ranking test based on plaque score interpretation Group A: Green-tea, Group B: Green-tea plus ginger, and Group C: Chlorhexidine at baseline and after 15- and 30-days interval

Group	Rank at baseline	Rank after 15 days	Rank after 30 days	P*
Group A (GT)	1.3	2	2.68	0.000
Group B (GT+G)	1.28	1.88	2.85	0.000
Group C (CHX)	1.50	1.93	2.58	0.000

*P≤0.05: Chi-square test. GT - Green-tea; GT+G - Green-tea plus ginger; CHX - Chlorhexidine; P - Probability value

DISCUSSION

Mouth-rinse is most commonly used as an adjunct to the mechanical plaque control and is proven to be effective in providing complete plaque removal. CHX mouthwash, with its substantivity and anti-bacterial property, has been considered as a 'gold standard since long.[14] However, it is associated with certain adverse effects such as tooth-staining, burning of oral mucosa, and alteration in taste sensation.[8] Hence, there is a need for new herbal mouth-rinse with minimal side effects and improved patient compliance. Among various herbal agents used routinely, GT and ginger are most commonly consumed worldwide. These plant extracts have antibacterial, anti-inflammatory, and anti-oxidant properties.

GT, obtained from plant C. sinesis, is the most consumed beverage all over the globe and has been known for its medicinal benefits. Various in vitro as well as in-vivo studies have reported anti-inflammatory, anti-oxidant, and anti-microbial properties of GT. A study by Jenabian et al. reported the anti-plaque effect of GT when compared to normal saline and highlighted the anti-inflammatory property of GT.[15] This property of GT is associated with the presence of various catechins and polyphenolic compounds present in GT. It also inhibits enzyme collagenase and metalloproteinase-9, thereby limits the destruction of the tissue and alveolar bone by periodontal pathogens.[16]

Ginger is known for its beneficial properties since centuries and is widely used as herbal medicine, especially in the Indian population, owing to anti-inflammatory, anti-oxidant property, and anti-microbial property. It has an ability to inhibit the synthesis of inflammatory mediators such as prostaglandins and leukotrienes by acting on enzymes cyclo-oxygenase and 5-lipoxygenase, respectively. Furthermore, it is effective against pathogens such as Prevotella intermedia, Porphyromonas gingivalis, and Porphyromonas endodontalis responsible for gingivitis and periodontitis.[1718]

An in vitro study by Anshula et al. reported the stability of formulations of mouth-wash containing GT and GT plus ginger at various time intervals and concluded that it can be used for further in vivo studies.[12]

In the present study, the results indicated that there was a significant reduction in the gingival score in all the three groups. Herbal mouthwash containing GT has shown significant reduction in gingival score after 15 days (1.69 ± 0.35) and 30 days (1.43 ± 0.35) as compared to the baseline score (1.94 ± 0.32). Similar finding was also reported by Singh et al., and Priya et al., wherein GT mouthwash had significant reduction in gingivitis as compared to CHX.[1920] Furthermore, herbal mouthwash containing both GT and ginger has shown high significant reduction in gingival score, after 15 days (1.71 ± 0.31) and after 30 days (1.22 ± 0.29) as compared to baseline score (1.99 ± 0.29).

The results of the present study indicated that there is a significant reduction in the gingival score and plaque score, with the use of herbal mouthwash containing GT and combination of GT plus ginger. These herbal mouthwashes had better efficacy compared to CHX mouthwash in reducing gingivitis and plaque.

Researchers also evaluated plaque score; the results indicated significant reduction in plaque score in all the three groups. Herbal mouthwash containing GT has shown significant reduction in plaque score after 15 days (1.61 ± 0.52) and 30 days (1.19 ± 0.49) as compared to the baseline score (1.90 ± 0.51). Similar finding was also reported by Singh et al., Priya et al., Biswas et al., and Kaur et al., wherein GT mouthwash had significant reduction in plaque score as compared to CHX.[16192021] Herbal mouthwash containing both GT and ginger has also shown high significant reduction in gingival score, after 15 days (1.35 ± 0.56) and after 30 days (0.89 ± 0.38) as compared to baseline score (1.76 ± 0.55). To our knowledge, this is the first study to compare the efficacy of mouthwash containing both GT and ginger with CHX. In accordance to our study, previous study by Shrimathi et al. reported reduction in the number of lactobacillus count after using mouthwash containing ginger due to its anti-plaque activity.[22] An in vitro study done by Weli and Mohammed reported the anti-microbial activity of ginger extract against S. mutans; however, its efficacy was less when compared to CHX mouthwash.[23] Other study by Deshpande et al. also concluded the beneficial effect of GT as a regular drink on gingival health.[24]

On inter-group comparison, it was concluded that gingival score and plaque score were lowest in Group B (GT plus ginger), followed by Group A (GT) and Group C (CHX). This can be attributed to the synergistic effect of both ginger and GT. The presence of phenolic compounds such as shogaol and gingerol in ginger and polyphenols in GT contributes to the anti-inflammatory and anti-microbial action of these mouthwashes, thereby leading to significant decrease in gingivitis and bacterial plaque accumulation.

This was the first study to compare the efficacy of GT, GT plus ginger, and CHX mouthwash. Both of the herbal mouthwash showed improved patient compliance with no adverse effects in contrast to that of CHX mouthwash. However, further studies are needed to evaluate the long-term effect of these mouthwashes on larger population.

CONCLUSION

The results of the present study indicate that there was significant reduction in plaque score and gingival index score in children after using mouthwash containing GT plus ginger, followed by mouthwash containing GT and CHX. Thus, it can be concluded that herbal mouthwash can be used effectively as an alternative to CHX and as an adjunct to mechanical plaque control.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.