Protein, albumin and cystatin concentrations in saliva of healthy subjects and of patients with gingivitis or periodontitis.

Salivary protein, albumin and cystatin concentrations were investigated in subjects with a healthy periodontium and in patients with gingivitis or periodontitis. Protein and albumin concentrations in saliva of individuals with gingivitis or periodontitis were significantly increased compared with healthy subjects. Salivary protein and albumin appeared to be positively correlated in all the groups, which suggests that the increase in salivary protein concentration in subjects with gingivitis or periodontitis is caused by leakage of plasma proteins. Cystatin concentrations in saliva of subjects with periodontitis were significantly increased when compared with the healthy group and the gingivitis group (p < 0.01). In the gingivitis and periodontitis group, salivary cystatin was only weakly correlated with albumin concentrations, which suggests that the increased salivary cystatin activity found in subjects with gingivitis and periodontitis is derived from sources other than plasma.