Enamel is a living membrane that can be easily softened and demineralized by acids. Dentists cannot stop enamel damage - only removing the acidity can prevent damage.

Mouth acidity is measured in the pH of saliva. A pH above 7.0 is a safe, alkaline state. A pH below 7.0, it is acidic. The root surfaces of teeth can be damaged when acidity drops below 6.5 and tooth enamel erodes if levels fall to pH 5.5. The longer teeth remain in acidic saliva, the greater the damage from demineralization. Yet, when saliva levels are alkaline, teeth can strengthen and repair through a natural process of tooth remineralization. The longer the mouth pH remains alkaline, the greater opportunity for teeth to repair themselves.

Mouth pH can fluctuate for a number of reasons related to diet, body chemistry and hormones, climate, or mouth dryness. Anything that causes a drop in the mouth pH to make it acidic or to cause mouth dryness is a risk factor for dental disease. The greater your risk for dental disease, the more protection you will need to keep your teeth safe from damage.

To understand and control mouth acidity, it is useful to test for saliva pH. You can easily keep the mouth in an alkaline state by eating xylitol. Xylitol protects teeth from mouth acidity and helps remineralize and repair them.

Nature’s Response
When you bite into a lemon you naturally produce saliva in your mouth. This is nature’s way to wash away the acidity and protect your teeth. Without help from saliva the acids in your mouth would dissolve calcium out of your teeth.

Saliva brings calcium and minerals to the tooth and helps repair any damage. It takes about 20-30 minutes for nature to dilute and remove the damaging acids from your mouth. This graph illustrates how acidity puts your mouth below a safe level but there is natural recovery over time.

Sipping drinks
Problems occur if you drink more acid before the mouth has recovered. Constant sipping can keep the mouth in an acid state for hours and in this way teeth are damaged. This graph illustrates the way frequent sipping can keep the mouth at damaging levels.

Damage in a dry mouth
AAnyone with a dry mouth will be at greater risk of tooth damage. Without saliva there is no natural response to wash away the acids. People with blocked noses or who breathe through their mouths have less saliva. Allergies, sinus problems, exercise or even sleep can put you at risk for acid damage.

Dry mouths offer greater risk of dental damage. While some dry mouth is permanent, caused by disease or radiation damage, everyone wakes with a dry mouth following sleeping, when less saliva is produced, so everyone shares this risk.