I believe our ancient tooth powder (the umikkari mix) was the best one in the world! umi(powdered paddy shell) is burnt to form "kari"(carbon) which is them mixed with pepper, salt and dried leaves of neem. The second toothpaste was mango leaves! Pick a ripe mango leaf bite it to form a paste and use it to brush. The stem of the leaf can be used asa tongue cleaner. My grandpa still uses the latter tooth paste. No wonder he can eat murukku even at the age of 85!
I did some research on the tooth paste, almost all the popular brands have one abrasive of the other(mainly bone powder) which destroys our enamel.. All the tooth whiteners have such abrasives that they remove one layer of the enamel revealing the bottom one which will be white... If somebody interested in a natural tooth powder you can try "dashana kaanthi" from "Kottakkal Arya vadiya sala" ... apply it on the teeth and gums and wait for a couple of minutes.. Then brush with a soft bristled toothbrush!! U (and your teeth) will thank me after 30-40 years!
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