Gargling with tea is being tested as a treatment for reducing the build-up of plaque on teeth. A trial in India will compare green and black tea with an antiseptic mouthwash. Around 45 people with gingivitis - a form of gum disease - will be given one of the teas or a mouthwash containing chlorhexidine to rinse with for 30 seconds, twice a day after brushing. The levels of plaque on their teeth will be measured throughout the two-week trial at Sri Hasanamba Dental College and Hospital in India. Plaque forms when we eat and drink - some bacteria in plaque are harmful and, if left to build up, can lead to gum disease. It's thought tannin, a chemical in tea, may have antibacterial properties. Source: dailymail.co.uk/health/article-3269842/For-clean-teeth-try-gargling-tea-Tannin-s-antibacterial-properties-reduce-build-plaque.html