Does the mouth have any natural resistance to plaque?

Asked by: Neil Watkins, by email

Yes, alkaline saliva. The minerals in your teeth are continually dissolving and re-depositing in a dynamic equilibrium mediated by mouth pH. If your mouth pH is neutral, the two processes are exactly balanced and there is no net effect. The more acid your mouth is, the further the equilibrium point is pushed towards dissolving your teeth. If your mouth is sufficiently alkaline, minerals get re-deposited on your teeth. This can be a problem in extreme cases as it causes tartar build-up. Within about 10 minutes of eating and for about half an hour after that, the natural alkalinity of your saliva is overwhelmed before returning to an alkaline pH.

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