The OTHER Role of Saliva

When saliva is mentioned, most would associate it with the digestion of food. That is what we were taught in secondary school biology.

However, saliva has an even more important role, i.e. to protect our teeth from decay. Saliva's buffering capacity has a moderating effect on the acids that we ingest on a daily basis. This prevents an acid attack which can soften the surface of our teeth.

For example, if we have our customary breakfast orange juice and brush our teeth after that, we would be brushing away some of our teeth. Over time, we would have removed enough tooth substance to expose the nerves in our teeth. Not a pleasant experience.

As dentists, we need to determine the cause of the decay before we treat the cavity otherwise the decay would recur. This would involve the use of salivary test to determine salivary pH and salivary flow rate.

Salivary pH can be reduced when there is a shift in fluid balance as a result of execrise. A lack of hydration on the other hand would reduce salivary flow.

Sometimes, the medication that we take would also affect our salivary flow. In patients being treated for Rheumatoid Arthritis, one out of three would suffer from dry mouth. It is more likely to occur in female Rheumatoid Arthritis patients. This would inevitably lead to numerous teeth having decay, especially on the roots of the teeth, which is the most difficult to treat. Patients with Hepatitis C and diabetic patients would also suffer from dry mouth and up to 50% of patients would be affected. Dry mouth from these conditions is the result of Secondary Sjogren's Disease.

Conversely, with orthodontic (braces) treatment, there would be an increase in salivary flow. There is also a related change in the bacterial colonies in the mouth and an increase in bacterial count.

Thus, it is important for the dentist to regularly to assess the patient's caries risk and to tailor treatment to address those needs. Patients who suffer from Rheumatoid Arthritis, Hepatitis C and diabetes should visit the dentists more frequently so that any dental problems can be detected and treated early to prevent further adverse consequences.