Alpha-defensin levels in whole saliva of totally edentulous subjects

Salivary levels of alpha-defensins 1-4 and histatins 1, 3 and 5 were determined in 11 totally edentulous patients, 11 younger healthy adults with normal gingival mucosa (Control group I) and 8 subjects, age-matched with edentulous patients, having a minimum of 25 teeth (Control group II). Whole saliva was treated with trifluoroacetic acid and the acidic soluble fraction analyzed by High Performance Liquid Chromatography-Mass Spectrometry. The area of the extracted ion current peaks was used for peptide quantification. Levels of alpha-defensins1-4, but not of histatins, were significantly lower in totally edentulous patients with respect to both Control group I and Control group II. The two control groups did not show significant differences. The reduced level of oral alpha-defensins, which are mainly of crevicular origin, is most likely due to the absence of the gingival sulcus in the edentulous subjects. The near absence of alpha- defensins might be in part responsible for the higher vulnerability of the oral cavity to oral pathogen infections observed in totally edentulous patients.