Oral Antimicrobial Peptides and Biological Control of Caries

The presence of antimicrobial peptides (AMPs) in saliva may be a biological factor that contributes to susceptibility or resistance to caries. This manuscript will review AMPs in saliva, consider their antimicrobial and immunomodulatory functions, and evaluate their potential role in the oral cavity for protection of the tooth surface as well as the oral mucosa. These AMPs are made in salivary gland and duct cells and have broad antimicrobial activity. Alpha-defensins and LL37 are also released by neutrophils into the gingival crevicular fluid. Both sources may account for their presence in saliva. A recent study in middle school children aimed to determine a possible correlation between caries prevalence in children and salivary concentrations of the antimicrobial peptides human beta-defensin-3 (hBD-3), the cathelicidin, LL37, and the alpha-defensins. The levels of these AMPs were highly variable in the population. While levels of LL37 and hBD-3 did not correlate with caries experience, the mean alpha-defensin level was significantly higher in children with no caries than in children with caries (p < 0.005). We conclude that several types of AMPs that may have a role in oral health are present in unstimulated saliva. Low salivary levels of alpha-defensin may represent a biological factor that contributes to caries susceptibility. Our observation could lead to new ways to prevent caries and to a new tool for caries risk assessment

Stimulating the discussion on saliva substitutes: a clinical perspective

Xerostomia is a significant problem commonly faced by patients and oral health practitioners. There is no cure for this condition, which commonly manifests as a side effect of medications, head and neck irradiation and other systemic conditions, such as Sj€ogren’s syndrome and type 2 diabetes. It may also arise idiopathically. Therefore, treatment is palliative and takes the form of oral lubricants and saliva substitutes which aim to reduce symptoms associated with xerostomia as well as prevent oral disease secondary to it. Recently there has been an expansion of the number and range of products available in Australia for the palliative management of xerostomia. It is imperative then that oral health professionals have a sound understanding of the advantages and disadvantages of using such products as patients tend to be well informed about new products which are commercially available. This article discusses some of the most commonly available products used for the symptomatic relief and preventive management of xerostomia. Amongst the plethora of products available to the patient suffering from xerostomia, no single product or product range adequately reproduces the properties of natural saliva and therefore consideration of patients’ concerns, needs and oral health state should be taken into account when formulating a home care regime. With Australia’s ageing population and its heavier reliance on medications and treatments which may induce xerostomia, oral health professionals are likely to encounter this condition more than ever before and therefore an understanding of xerostomia and its management is essential to patient care