OBJECTIVE: To determine salivary pH, flow rate (FR) and surface tension (Upsilon(s)) in a cohort of 30 healthy young adults. To acquire cohort biological independent variables (age, gender, weight, height, medications, smoking, pathologies, and allergies) and to correlate them with pH, FR and Upsilon(s) obtained values. Evaluate the possible variation of the Upsilon(s) values during the time after the withdrawal and the influence of the operational abilities of the experimenting operators. Evaluate the relationship between Upsilon(s), pH and FR and the dependence between pH and FR. PATIENTS AND METHODS: Non- stimulated saliva samples were taken in four different time span, for three days, with a drooling method for 15 minutes. The saliva sample was analyzed, in terms of Upsilon s, by two different operators (OP1 and OP2), twice consecutive (Upsilon(s)-1 and Upsilon(s)- 2) for a total of 360 measurements. The Upsilon(s) was calculated using the du Nouy method. The FR was evaluated by weighing technique and pH by pH indicator papers. RESULTS: The measurements of.s performed by two different operators (OP1, OP2) showed respectively average values of 46.46 mN/m and 43.45 mN/m, while the mean FR was 0.29 +/- 0.13 mL/min and the average pH was 7.1 +/- 0.43. There were no significant correlations between.s and the biological variables analyzed. CONCLUSIONS: We can consider as reference values, in a sample of young adults, Upsilon(s) 45.56 +/- 6.51 mN/m.
