The Antiplaque and Antigingivitis Effect of Pure Green Tea Mouth Wash Compared to Placebo and Essential Oils Mouth Washes

• Study Design This study will be a double-blinded, randomized, controlled, clinical trial with a parallel group design. Participants will be randomly allocated into four groups: Group P: placebo (pure water with a flavored additive) solution. Group T1: pure green tea mouthwash. Group T2: Listerine Total Care mouthwash. Group T3: Listerine Green Tea mouthwash. All participants will be instructed to rinse with 10 ml of the assigned mouthwash for 30 seconds twice daily over a three-week experimental period. The study will follow the experimental gingivitis model, during which participants will refrain from all forms of mechanical plaque control. * Sample Size A total of 44 dental participants, aged between 18-50 years, will be recruited. Each group will consist of 11 participants, providing a power of 80% to detect a difference of 0.2 in mean plaque index values between groups, with a p-value \< 0.05 and a β-error of 20%. * Ethical Considerations All participants will be informed about the study objectives, methodology, and possible risks. Written informed consent will be obtained before participation. All procedures will follow ethical standards and the principles of the Declaration of Helsinki. * Data Collection and Clinical Assessments Clinical examinations will be performed at baseline (T0), day 7 (T1), day 14 (T2), and day 21 (T3). The following parameters will be recorded: plaque index, gingival index, staining index, and patients reported outcome in regards to their perciption of freshness and good breath. After the experimental period (T3), participants will receive a professional cleaning and fluoride application, and will be followed for two additional weeks to ensure the restoration of oral health. * Randomization and Blinding Randomization will be performed using a computer-generated sequence by an independent researcher. The mouthwash samples will be provided in coded and unlabeled containers to ensure blinding of both participants and the examiner. A third party will be responsible about desposing the assigned mouth wash to the patients. * Adverse Events Monitoring Participants will be closely monitored throughout the study for any possible adverse effects such as gingival irritation, sensitivity, or allergic reactions. Any incident will be documented and managed according to the study protocol. Any participant who experience an adverse event will be excluded from the study.