[Effect of 3 saliva collection methods on salivary secretion]

This study compared the effect of 3 saliva collection methods on salivary secretion, in order to select optimum collection method for follow-up studies.

Fifty-five young healthy volunteers' saliva samples were collected by EP tube collecting emulated with natural flow (ETC), rotating mouth swab slightly (RMS) and chewing mouth swab (CMS) before and after stimulating with acid. The salivary flow rate, salivary alpha-amylase (sAA) activity of each saliva sample and its ratio before and after stimulating with acid were detected to provide the basis for the preferred method of collecting saliva. SPSS 17 software package was used to compare the results before and after acid stimulation.

The salivary flow rate ratio (1.73 ± 1.35 and 1.37 ± 0.82, respectively), sAA activity ratio (1.22 ± 0.38 and 1.10 ± 0.30, respectively) and unit time total sAA activity ratio (2.12 ± 1.57 and 1.56 ± 1.18, respectively) of ETC and RMS increased after acid stimulation with the same tendency, and the detection rate of the indexes were closer between ETC and RMS (salivary flow rates: 80%, 78.2%; sAA activity:67.3%, 60.0%; unit time total sAA activity: 83.6%, 76.4%, respectively). Among them, RMS had the advantage of objective and paralleled to collect sufficient amount of saliva. However, the results of CMS were quite different with the first two methods. The detection rate of each index ratio increased in the CMS (salivary flow rate, sAA activity and unit time total sAA activity were 67.3%, 40%, 61.8%, respectively) was significantly lower than the first two, and did not accurately reflect the status of sAA activity in healthy people after acid stimulation.

RMS is recommended when studying on the variation of salivary secretion before and after salivary gland stimulated by acid.