Bad breath, which can make the other person's feelings worse, in the situation where the quality of life is improving, is now causing the social life not to be smooth, apart from the concept of oral disease [1]. Bad breath is a product of bacterial decay and hydrogen sulphide (VSC), hydrogen sulfide (H2S), methyl mercaptan (CH3SH) and dimethyl sulfide (CH3SCH3). And, it is an unpleasant smell that the anaerobic bacterium comes out through the mouth of [2,3] substances produced by decomposing amino acids, peptides and proteins containing sulfur.

The causes of halitosis can be divided into intraoral factors and external factors. Bad breath due to oral causes is a result of host factors such as tooth and saliva components and food residues being corrupted by bacteria. This is known that oral malodor such as to reduced saliva secretion, stomatitis, periodontal disease, improper prosthesis, excessive microbial deposit at the tongue site, stimulant food intake, smoking, drinking and other things, increased saliva viscosity, decreased hydrogen ion buffering capacity, increase the amount and activity of oral microorganisms ,coated tongue attached to the back of the tongue, untreated dental caries, gingivitis, and periodontal disease are the causes of bad breath [4]. The number of patients with gingivitis and periodontal disease, and the cost of care, increased by more than 10% each year from 2011 to 2013, according to the 2014 Health Insurance Review and Assessment Service statistics.

In order to reduce halitosis, there have been many attempts to use antimicrobial substances capable of chemically inhibiting the growth and proliferation of bad breath-producing microorganisms in combination with how to control coated tongue such as brushing, tongue brushing, and flossing. Products using toothpaste, spray-type dentifrice, goggle-type toothpaste, etc. are continuously developed and various products are being sold [5,6] using chlorhexidine essential oil, cetylpyridinium chloride, which is an artificial synthetic material.

In this study, polyphenol, which is a natural material contained in green tea extract, and sodium fluorophosphate, which is a fluorine compound, are used for chemically synthesized materials. Most fluorides are compounds in toothpastes and there are reports of limited use in food additive or mouth wash. Polyphenol, a natural material, is a generic term for phenolic hydroxyl (OH) compounds in plants produced by photosynthesis of plants, and can be said to be a component having antioxidant activity. The polyphenols contained in green tea are generally known as (+) catechin, (−) epicatechin, (+) gallocatechin, (+) epigallocatechin, (−) epigallocatechin gallate and (−) epicatechin gallate. Particularly, catechin is used to prevent dental caries, but it has a disadvantage that it is more expensive than chemical synthetic materials [7,8].

Green tea extracts have been reported to have various effects such as antibacterial, anticancer, periodontal regeneration, gingivitis suppression, and reduction of bad breath [9], but there is little systematic study of the effect of mouth wash combined with sodium fluorophosphate. This study aims to investigate bad breath control effect of mouth wash combined with sodium fluorophosphate and green tea extract.

1. Subject

The subjects participated in this study were 60 adult males and females (16 males and 44 females) aged between 20 and 60 years who agreed in writing and recruited the subjects by referring to the announcement of the approved research ethics committee. In addition, the subjects who had more than 24 teeth remaining without the crown cervical caries or restorations and who had regular brushing twice a day and had mild to moderate gingivitis were selected as subjects. The age and distribution of subjects were as follows (Table 1).

Table 1 . Gender and age distribution of subjects

Gender	Age group
	Total	20 s	30 s	40 s	50 s
Total	60	26	19	7	8
Male	16	4	6	3	3
Female	44	22	13	4	5

2. Mouth wash

The mouth wash solution provided to the study subjects was formulated as an effective ingredient recognized by FDA. The control group was only used as a standard mouth wash containing added basic ingredients such as wetting agents, foaming agents and fragrances, combined wetting agents, foaming agents, fragrances and the like. In the experimental group, mouth wash containing 0.76% of sodium fluorophosphate and 0.04% of green tea extract was used as a basic ingredient. The ingredients of the study mouth wash are shown in (Table 2, Figure 1).

Table 2 . Ingredients and content of dentifrice

Ingredient	Con. group	Exp. group
Sodium fluorophosphate	-	0.76 %
Green tea extract	-	0.04 %

Exp: experimental group, Con: control group.

Figure 1. Experimental mouth washing.

3. Method

DanKook University IRB (DKU 2017-11-003-002) approved.

The study was conducted for 8 weeks in a single-blind test that does not tell us whether it belongs to the experimental group or the control. Randomized study ID numbers were assigned and the test and control groups were assigned and classified as 1:1.

The mouth wash, which was given to the control group and the experimental group respectively, was used three times a day (after breakfast, after lunch, and after dinner). The use of mouth wash. Was performed by brushing using additional toothpaste and toothbrush, and then using a proper amount (10 cc) for 1 minute in the mouth.

In the first visit, after a simple survey such as medical history, history of alcohol ingestion and smoking was conducted to find out whether the subject was suitable for the study, I explained the procedure and received written consent.

In the second visit, at least 1 week interval was performed. The oral examination index was measured, the brushing method was taught by the rotation method, and mouth wash was distributed.

In the third visit, three days after the second visit, the adverse reaction was confirmed and the oral examination index was measured.

In the fourth visit, five days after the second visit, the adverse reaction was confirmed and the oral examination index was measured.

In the fifth visit, four weeks after the second visit, the adverse reaction was confirmed and the oral examination index was measured, and oral mouth wash was further distributed.

In the sixth visit, eight weeks after the second visit, the adverse reaction was confirmed and the oral examination index was measured.

Patient Hygiene Perfomance Index, Plaque Index and Oral Index were measured before, 3 days after use, 5 days after use, 4 weeks after use, 8 weeks after use, total 5 times.

After coloring the tooth with a disclosing agent and rinsing the mouth with water, using dental unit-chair probes and crowns, the remaining coloration of only labial surface (or buccal) and lingual surfaces was investigated.

One side of the tooth was divided into 5 equal parts by mesial, distal, incisal, occlusal, and cervical centrals and then, buccal surface of left and right maxillary first molars, labial surface of the upper and lower incisors, and the lingual surfaces of the left and right mandibular first molars were exa-mined.

If the dentine bacterial membrane is colored on the irradiation site, one point is given. If there is no dentine bacterial membrane on the irradiation site, no point is given. Per side was a five point scale. When the test teeth were divided into 6 teeth, the highest index was 5 points and the lowest index was 0 points.

The gingiva per tooth was divided into two teeth (sagittal and lingual surfaces), and the sum of the indexes was averaged by the number of teeth. The rating criteria are as follows.

The rating criteria of the Plaque Index were applied by Quigley & Hein's Turesky modification standard, and the target teeth were measured 15, 13, 26, 44, 32, 36.

0 : If the dentine bacterial membrane is not attached at all

1: If there is a plaque index in the gingival margin part

2: line attachment along the gingival margin (When there is a Plaque Index of 1 mm or less)

3: If there is a plaque Index up to 1/3 of the cervical side

4: If there is a plaque Index up to 2/3 of the cervical side

5 : If there is a Plaque Index beyond 2/3 of the cervical side

The bad breath test was carried out by the participant in the dental clinic through the BB checker mBA-21 aerobic gas analyzer and the following procedure was performed.

After connecting the adapter, warm up for 5 minutes. Then click on the OG button to start the bad breath measurement, then shut off the mouth for 180 seconds of countdown and collect the gas in the mouth by non-breathing. If the alarm sounds after 3 minutes, insert the sensor with the mouthpiece into the mouth. After that, stop breathing and measure the bad breath for 15 seconds. At this time, the measurement sensor and the mouthpiece should be placed in the oral cavity of about 4 to 5 cm, so that the teeth and the lips are lightly held. When the experiment is finished, record the measured value displayed on the liquid crystal display (Figure 2).

Figure 2. Oral malodor check.

The statistical analysis of this study was performed on a per-protocol (PP) set (study subjects who complied with a certain level of the human body test protocol and completed the test). By performing a regularity test on the distribution of data, in the case of non-normal distribution data, the data were transformed by log transformation, square root transformation, and so on to form a normal distribution, followed by parametric analysis, or by non-parametric method for non-normal distribution data.

The collected data were analyzed using the SPSS 24.0 statistical package. The significance level (p-value) for statistical significance was 0.05.

2-sample t-test was performed for comparison between the control and experimental groups. Comparisons between groups were made by Paired t-test to compare the degree of bad breath occurrence.

The objective bad breath measured using BB Checker before the treatment was 77.32 in the experimental group and 80.24 in the control group. There was no statistically significant difference between the experimental group and the control group before the experiment, and the homology between the two groups was verified.

1. PHP Index

The trend of group-to-group PHP changes over 8 weeks was 2.13 at the beginning of the experiment, 2.09 after 5 days, 1.96 after 4 weeks, and 1.95 after 8 weeks in the control group as shown in Table 1. There was a significant difference between the experimental group and the control group after 8 weeks (Table 3).

Table 3 . Changes of dental PHP index

Group		Base	3 day	5 day	4 wks	8 wks
Exp.group	mean	2.17	2.09	2.02	1.90	1.63*
	SD	0.50	0.46	0.45	0.44	0.40
Con. group	mean	2.13	2.09	2.09	1.96	1.95
	SD	0.36	0.42	0.39	0.34	0.33
p-value*		.692	.982	.575	.600	.002

SD: standard deviation, Exp: experimental group, Con: control group.

⁺p-value by 2 sample t-test.

*p<0.05 by paired t-test between base and after.

2. Turesky Index

The trend of group-to-group Turesky Index changes over 8 weeks was 2.16 at the beginning of the experiment, 2.08 after 5 days, 2.14 after 4 weeks, and 2.06 after 8 weeks in the control group as shown in Table 2. There was a significant difference between the experimental group and the control group after 4 weeks (Table 4).

Table 4 . Changes of dental Turesky Plaque Index

Group		Base	3 day	5 day	4 wks	8 wks
Exp. group	mean	2.19	2.15	2.02	1.85*	1.78*
	SD	0.18	0.22	0.16	0.13	0.35
Con. group	mean	2.16	2.17	2.08	2.14	2.06
	SD	0.19	0.17	0.20	0.18	0.34
p-value*		.648	.759	.177	<0.001	.004

SD: standard deviation, Exp: experimental group, Con: control group.

⁺p-value by 2 sample t-test.

*p<0.05 by paired t-test between base and after.

3. Using BB Checker

The trend of group-to-group BB Checker changes over 8 weeks was 80.24 at the beginning of the experiment, 77.07 after 5 days, 77.14 after 4 weeks, and 74.72 after 8 weeks in the control group as shown in Table 3. There was a significant difference between the experimental group and the control group after 4 weeks (Table 5).

Table 5 . Changes of BB Checker Index

Group		Base	3 day	5 day	4 wks	8 wks
Exp. group	mean	77.32	75.25	73.82	67.75*	60.11*
	SD	14.71	13.22	10.52	11.38	14.31
Con. group	mean	80.24	73.31	77.07	77.14	74.72*
	SD	11.39	13.60	11.63	10.39	12.15
p-value*		.405	.258	.274	.002	.001

SD: standard deviation, Exp: experimental group, Con: control group.

⁺p-value by 2 sample t-test.

*p<0.05 by paired t-test between base and after.

4. OH Index

The trend of group-to-group OH Index changes over 8 weeks was 4.31 at the beginning of the experiment, 4.21 after 5 days, 4.24 after 4 weeks, and 4.14 after 8 weeks in the control group. And in the experimental group, it was measured as 4.43 at the beginning of the experiment, 4.21 after 5 days, 4.11 after 4 weeks, and 3.89 after 8 weeks. There was no significant difference between the experimental group and the control group (Table 6).

Table 6 . Changes of OH Index

Group		Base	3 day	5 day	4 wks	8 wks
Exp. group	mean	4.43	4.57	4.21	4.11	3.89
	SD	1.35	1.26	1.10	1.07	0.99
Con. group	mean	4.31	4.28	4.21	4.24	4.14
	SD	0.97	0.80	0.77	0.74	0.95
p-value*		.704	.293	.977	.582	.346

SD: standard deviation, Exp: experimental group, Con: control group.

⁺p-value by 2 sample t-test.

*p<0.05 by paired t-test between base and after.

As the level of living improves, the importance of mouth care increases and interest in mouth wash is increasing. The mouth wash is generally used to maintain a refreshing sensation in the oral cavity, such as mouth washing and halitosis removal. Depending on the product characteristics, products with additional functions such as tooth decay prevention, plaque and gum disease prevention are being released. To emphasize the characteristics of the product, it is also referred to as various names such as mouth wash, mouth washer, oral rinses, or gargle.

In recent years, many toothpastes have been developed to add therapeutic effects by adding various medicines. For this purpose, quinternary ammonium compounds, boric acid, benzoic acid, and phenolic compounds are widely used in mouth washes currently on the market [16].

The major components that are responsible for the main functions are antimicrobial agents to obtain antimicrobial effects and fluoride to prevent dental caries. It also contains alcohols or surfactants to dissolve some water-insoluble ingredients. And flavoring agents to give a unique flavor [14]. Of the ingredients of mouth wash, antibacterial ingredient that is used as the most important objective is diverse and has recently even the effort to discover and develop new antibacterial ingredients in the world it is going on. These antimicrobial ingredients can be categorized into cationic, anionic, nonionic, and other antimicrobial substances depending on the nature of the ion. A representative cationic antimicrobial agent is chlorhexidine. Among the most widely used agents in domestic toothpaste are quaternary ammonium compounds such as cetylpyridinium chloride (CPC), heavy metals, and plant extracts. Among them, chlorhexidine has a strong binding force with both organic and inorganic substances and has a characteristic that the residual effect lasts for a long time, thereby proving its effectiveness as the most effective antibacterial agent for therapeutic use. In addition to these antibacterial components, fluoride-containing mouth washes have been used to prevent dental caries or to remineralize early dental caries rather than antimicrobial and anti-gingivitis effects. In recent years, arginine and calcium carbonate are contained in toothpaste and used for the purpose of alleviating the hypersensitivity symptoms [13]. Thus, it can be seen that the substances added to the mouth wash have a great effect not only in preventing various types of dental diseases but also in improving oral health.

Green tea extracts have natural antimicrobial and antioxidant properties and have been shown to improve oral hygiene in particular. Antioxidants are believed to fight active oxygen attacking healthy cells, and green tea extracts are known to be powerful antioxidants in the scientific community and in the medical community, consisting of a polyphenol mixture called catechin. Therefore, it is known that green tea extract can inhibit the formation of the dentine bacterial membrane in oral cavity, and it is effective in preventing gingivitis caused by anti - inflammatory action and suppressing volatile sulfur compounds, thereby eliminating bad breath. Potassium nitrate is also known to be effective in relieving dental hypersensitivity and dental hypersensitivity symptoms, and is used as an agent for dentifrice and mouth washes [10].

sodium fluorophosphate (Na2FOO3) is not present as fluorine itself and is present in the form of 31.9413% of sodium (Na), 13.1979% of fluoride (F), 21.5170% of phosphorus (P) and 33.3437% of oxygen, it has been reported that the calcium supply promoting action strengthens the teeth. In addition, bacteria in oral cavity prevent tooth enamel from being dissolved by corrosive acid and inhibit the development of dental caries [15].

Green tea extract and sodium fluorophosphate, which are natural extracts, showed good efficacy in controlling bad breath reduction. It has not been studied how long the effect of bad breath reduction is retained after using mouth wash. Therefore, future studies will require more research on the effects of bad breath reduction after use and the adverse effects such as tooth discoloration after long-term use, using more test subjects.

To evaluate the effect of oral mouth wash containing sodium fluorophosphate (0.76%) and green tea extract (0.04%) on bad breath reduction, 60 patients were divided into experimental group and control group, respectively. Using the standard mouth wash with only the basic incense solution and wetting agent, after 3 days, 5 days, 4 weeks, and 8 weeks, PHP Index, Turesky Index and bad breath index were measured and the following conclusions were obtained.

1. The PHP Index showed a statistically significant reduction in the experimental group (1.63) compared to the control group (1.95) after 8 weeks in the experimental group (2.17) and the control group before experiment (2.13) (p<0.05).

2. Turesky Index showed a statistically significant reduction in the experimental group (1.85) compared to the control group (2.14) after 4 weeks in the experimental group (2.19) and the control group (2.16) before experiment (p<0.05).

3. BB Checker Value showed a statistically significant reduction in the experimental group (67.75) compared to the control group (77.14) after 4 weeks in the experimental group (77.32) and the control group (80.24) before experiment (p<0.05).

Because experimental mouth wash containing sodium fluorophosphate (Na2FPO3) and green tea extract was effective in reducing bad breath compared to the basic mouth wash used in the control group. I think it will be useful in clinical practice.

No potential conflict of interest relevant to this article was reported.