Role of Saliva in the Mouth
Role of Saliva in Health and Disease
Biofilms and Salivary mechanisms

Role of Saliva in the Mouth

Saliva is a complex multi-functional fluid; its lubricating properties help our mouths to perform all the day-to-day mechanical functions:  to chew, swallow, taste and speak; its composition helps to strengthen our teeth, facilitate digestion and control disease - oral and systemic.

As well as keeping the mouth moist and comfortable saliva plays a vital, everyday role in protecting our general health and wellbeing.  It is the combined action of saliva’s non-immune mechanisms such as lactoferrin, lysozyme and the peroxidase system, and its immune mechanisms such as immunoglobulins and growth factors which are essential for regulating oral conditions and maintaining your mouth’s ecosystem.

Role of Saliva in Health and Disease

Dentists know that maintaining healthy teeth and gums is a primary goal in the control of oral and systemic disease. 

Your mouth is a major route for the introduction of disease into the body.  Its constant, ambient temperature and the regular presence of moisture and nutrients make it a paradise for bacteria to thrive and multiply. 
Bacterial colonies which accumulate in the mouth are known as 'biofilms'.  Biofilms are responsible or more than 70% of oral bacteria.  If left untreated, biofilm bacteria are the cause of dental plaque, gum disease and tooth loss.

Evidence shows that biofilm bacteria, as well as affecting the quality of your teeth and gums, can lead to systemic disorders, Healthy teeth and gums, therefore, are not only important for the sake of our appearance and mouth comfort, but also to protect your general health and wellbeing. 

Regular tooth cleaning is essential to help remove the bacteria that can accumulate from eating or drinking, or those that are airborne.  In addition to clearing food particles, brushing your teeth can also stimulate the flow of your saliva – a fluid essential for mouth comfort and protection.

Biofilms and Salivary mechanisms

More than 70% of bacteria in the mouth are found in biofilms

Under normal conditions, the salivary systems continuously maintain a healthy balance in the mouth which helps prevent the formation of bacterial colonies, known as biofilm

Oral bacteria are present either individually (isolated or planktonic bacteria), or in organised layered colonies (biofilm).
Anaerobic bacteria situated in the inner layers of the biofilm attached to gums and teeth cause dental plaque and oral inflammation, often leading to progressive oral disease.
It has been demonstrated that the salivary molecules lactoferrin, lysozyme and immunoglobulins can react on the micro-organisms forming the outer layer of the biofilm and on isolated bacteria. Consequently they are not present to react against the bacteria located inside the biofilm. Similary, the active agent of the Salivary Peroxidase System, hypothiocyanite ions (OSCN-), acts on the bacteria located on the external surface of the biofilm and against isolated bacteria.
Their lack of efficacy against the bacteria located inside the biofilm is due to the dilution factor the molecules have to support when penetrating the biofilm.