Newer saliva collection methods and saliva composition: a study of two Salivette kits

Saliva is frequently used as a diagnostic fluid and several collection devices have been developed.

The aim of the present study was to investigate the validity and reliability of two types of Salivette collection kits (non-covered cotton roll and polypropylene covered polyether roll) relative to conventional collection of saliva using paraffin wax chewing stimulation.

Whole saliva samples were collected from 16 healthy volunteers. Following a cross-over design saliva was collected in a standardized way. The flow rate was determined and saliva samples were analyzed for pH, buffer capacity, electrolytes and protein/glycoprotein content.

We find that Salivette methods do not allow evaluation of flow rate. pH was unaffected but buffer capacity was lower in Salivette collected than in paraffin wax-stimulated saliva. The non-covered cotton rolls reduced the content of Na+, K+, Cl-, as well as glycoprotein markers (hexosamines, fucose, sialic acid), lysozyme, lactoferrin, salivary- and myeloperoxidase but increased the concentrations of Ca2+, PO4(3)- and SCN-. Polypropylene covered polyether rolls affected saliva composition less than the non-covered cotton rolls. Thus, SCN- and sIgA concentrations were higher and lysozyme activity lower in the former (covered roll) saliva than in paraffin wax saliva. The reliability of the Salivette kits was good.

We conclude that the Salivette method generates data significantly different from conventional paraffin wax-stimulated saliva such as buffer capacity and several electrolytes and organic components. Care should be taken in interpreting the results when such methods are employed.