Skip to main page content
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
, 80 Suppl 1, S3-S12

The Role of Natural Salivary Defences in Maintaining a Healthy Oral Microbiota


The Role of Natural Salivary Defences in Maintaining a Healthy Oral Microbiota

Anne Marie Lynge Pedersen et al. J Dent.


Objectives: To provide an update on our current understanding of how saliva and its various constituents directly and indirectly affect oral bacteria and thereby play a role in the modulation and maintenance of a healthy oral microbiota and also the associations with symbiosis and dysbiosis.

Methods: The search for biomedical literature on saliva and its antimicrobial activities (years 1966 to 2017) was conducted in PubMed, Embase and Web of Science databases.

Results: This review underlines that saliva plays an essential role in shaping and maintaining the ecological equilibrium of the resident oral microbiota. Saliva contributes to the formation of the salivary pellicle, which covers the oral hard and soft tissues, and thereby determines the initial adhesion and colonisation of microorganisms. Saliva facilitates clearance of dietary carbohydrates and microorganisms from the oral cavity, but also supplies bacteria with nutrients through enzymatic breakdown of dietary starch and proteins and salivary glycoproteins. In addition, saliva comprises proteins such as mucins, which block the adherence of certain microorganisms to oral surfaces through binding and aggregating mechanisms. Saliva also provides antimicrobial activity through numerous proteins and peptides including mucins, lactoferrin, lysozyme, lactoperoxidase, statherin, histatins and secretory immunoglobulin A.

Conclusions: A balanced oral microbiome is important for the maintenance of oral health and symbiosis. Conditions associated with salivary gland hypofunction, impaired oral clearance, low salivary pH and altered salivary composition, often lead to perturbation of the function and composition of the oral microbiome causing dysbiosis, and an associated risk of oral disease.

Clinical significance: Saliva plays a significant role in keeping the relationship between the host and oral microbiota in a symbiotic state. In conditions with salivary gland dysfunction, the natural balance of the oral microbiome is often disturbed, leading to dysbiosis and associated risks of gingivitis, caries and fungal infection.

Keywords: Amylase; Lactoferrin; Lysozyme; Oral microbiota; Peroxidases; Salivary mucins.

Similar articles

  • Antimicrobial Defense Systems in Saliva
    W van 't Hof et al. Monogr Oral Sci 24, 40-51. PMID 24862593. - Review
    The oral cavity is one of the most heavily colonized parts of our body. The warm, nutrient-rich and moist environment promotes the growth of a diverse microflora. One of …
  • Salivary Microbiota Reflects Changes in Gut Microbiota in Cirrhosis With Hepatic Encephalopathy
    JS Bajaj et al. Hepatology 62 (4), 1260-71. PMID 25820757.
    Dysbiosis, represented by reduction in autochthonous bacteria, is present in both saliva and stool in patients with cirrhosis, compared to controls. Patients with cirrhos …
  • Influence of Saliva on the Oral Microbiota
    PD Marsh et al. Periodontol 2000 70 (1), 80-92. PMID 26662484. - Review
    Saliva plays a major role in determining the composition and activity of the oral microbiota, via a variety of mechanisms. Molecules, mainly from saliva, form a condition …
  • Salivary Proteins: Protective and Diagnostic Value in Cariology?
    A Van Nieuw Amerongen et al. Caries Res 38 (3), 247-53. PMID 15153696. - Review
    Saliva is essential for a lifelong conservation of the dentition. Various functions of saliva are implicated in the maintenance of oral health and the protection of our t …
  • Saliva and Dental Caries
    FJ Dowd. Dent Clin North Am 43 (4), 579-97. PMID 10553245. - Review
    A study of saliva and its tooth-protective components reveals at least four important functions of saliva: (1) buffering ability, (2) a cleansing effect, (3) antibacteria …
See all similar articles

Cited by 7 PubMed Central articles

See all "Cited by" articles

LinkOut - more resources