Antibacterial Effect of the Infusion of Green Tea Used as a Mouthwash on Saliva and Bacterial Plaque


Given that the participation of oral microorganisms in the development of the most prevalent pathologies of the oral cavity is unquestionable, efforts have been made to create agents that allow controlling these bacteria. The objective of this work was to analyze the antibacterial effect of green tea infusion used as a mouthwash on saliva and bacterial plaque. The green tea infusion was prepared at 13% at approximately 90 ° C, being the same applied to 14 participants from the 1st to the 5th grade (experimental group); and to other 14 participants the placebo was applied (control group). The antibacterial effect was determined by counting the colony forming units (CFU) in the cultures of samples of bacterial plaque and saliva, taken before the application of the infusion and immediately after.

Full Title of Study: “Antibacterial Effect of the Infusion of Green Tea (Camellia Sinensis) as a Mouthwash on Saliva and Bacterial Plaque”

Study Type

  • Study Type: Interventional
  • Study Design
    • Allocation: Randomized
    • Intervention Model: Parallel Assignment
    • Primary Purpose: Prevention
    • Masking: Single (Participant)
  • Study Primary Completion Date: September 21, 2016

Detailed Description

Oral diseases, including dental caries, is one of the most prevalent in the population. It is multifactorial and originates from the formation of the bacterial plaque and its non-elimination by physical and chemical hygiene methods.

The use of chemical agents to aid in the control of Bacterial Plaque has been the subject of study in many investigations. Today there is a variety of elements that can be use to carry out proper oral hygiene, such as toothbrushes, toothpastes, dental floss and mouthwash, all of them in a wide variety.

Often the lack of accessibility to these means problems in the hygiene in the population, either due to the lack of knowledge or the cost of obtaining them.

Therefore, the objective of analyzing the antibacterial effect of the infusion of green tea (camellia sinensis) used as a mouthwash on saliva and bacterial plaque was presented. The proposed research topic is relevant, since if green tea (camellia sinensis) is found to produce positive effects on bacterial plaque, it would serve to prevent its formation, thus helping to improve dental hygiene with an easy acquisition product and lower cost compared to other mouthwashes offered in the market, constituting a natural mouthwash.


  • Other: Green Tea mouthwash
    • an infusion at 13%, with 13 g of green tea (commercially divided) in 100 ml of saline solution, at a temperature of approximately 90 ° C, in sterile glass containers. Each application was 10 ml. applied for 1 minute.
  • Other: Placebo Mouthwash
    • distilled water

Arms, Groups and Cohorts

  • Experimental: GREEN TEA MOUTH WASH
    • an infusion at 13%, with 13 g of green tea (commercially divided) in 100 ml of saline solution, at a temperature of approximately 90 ° C.
  • Placebo Comparator: Placebo
    • distilled water, in sterile glass containers.

Clinical Trial Outcome Measures

Primary Measures

  • Bacterial plaque Stage 1 (Before intervention)
    • Time Frame: thorough study completion, an average of 24 hours
    • The measure was done with the count of Colony forming units
  • Bacterial plaque Stage 2 (After intervention)
    • Time Frame: 1 minute after mouthwash use
    • The measure was done with the count of Colony forming units
  • Antimicrobial effect
    • Time Frame: up to 24 hours, thorough study completion
    • The measure was done with the difference in count of Colony forming units before and after intervention

Participating in This Clinical Trial

Inclusion Criteria

  • Participants that signed the informed consent

Exclusion Criteria

  • allergic to green tea (Camellia sinensis)
  • ongoing medical or dental treatment that could interfere with the results.

Gender Eligibility: All

Minimum Age: 18 Years

Maximum Age: N/A

Are Healthy Volunteers Accepted: Accepts Healthy Volunteers

Investigator Details

  • Lead Sponsor
    • Julieta María Méndez Romero
  • Provider of Information About this Clinical Study
    • Sponsor-Investigator: Julieta María Méndez Romero, Head of Writting and Publication Department, Regional Health Research Institute – Universidad Nacional de Caaguazu
  • Overall Official(s)
    • Jazmin Servin, Principal Investigator, Universidad Nacional de Caaguazu
    • Nelson Portillo, Study Director, Universidad Nacional de Caaguazu


Ardakani MR, Golmohammadi S, Ayremlou S, Taheri S, Daneshvar S, Meimandi M. Antibacterial effect of Iranian green-tea-containing mouthrinse vs chlorhexidine 0.2%: an in vitro study. Oral Health Prev Dent. 2014;12(2):157-62. doi: 10.3290/j.ohpd.a31663.

Megalaa N, Thirumurugan K, Kayalvizhi G, Sajeev R, Kayalvizhi EB, Ramesh V, Vargeese A. A comparative evaluation of the anticaries efficacy of herbal extracts (Tulsi and Black myrobalans) and sodium fluoride as mouthrinses in children: A randomized controlled trial. Indian J Dent Res. 2018 Nov-Dec;29(6):760-767. doi: 10.4103/ijdr.IJDR_790_16.

Ronanki S, Kulkarni S, Hemalatha R, Kumar M, Reddy P. Efficacy of commercially available chlorhexidine mouthrinses against specific oral microflora. Indian J Dent Res. 2016 Jan-Feb;27(1):48-53. doi: 10.4103/0970-9290.179816.

Hajiahmadi M, Yegdaneh A, Homayoni A, Parishani H, Moshkelgosha H, Salari-Moghaddam R. Comparative Evaluation of Efficacy of "Green Tea" and "Green Tea with Xylitol" Mouthwashes on the Salivary Streptococcus mutans and Lactobacillus Colony Count in Children: A Randomized Clinical Trial. J Contemp Dent Pract. 2019 Oct 1;20(10):1190-1194.

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