Salivary secretion: stimulatory effects of chewing-gum versus paraffin tablets

Paraffin tablets are commonly used in clinical saliva tests whereas chewing-gum is recommended to increase salivation in xerostomic patients. The aim of this study was to compare the effect on salivation of these stimuli. Saliva stimulated by chewing-gum or paraffin tablets was sampled on separate occasions from eight healthy subjects (25-45 yr). Whole or parotid saliva were collected for 6 min (1 min + 5 min) and 21 min (1 min + 5 min x 4), respectively. pH of saliva was measured with and without the addition of HC1 (titrated pH). Total parotid protein was measured using the microBSA-assay. Initially, flow rates were significantly higher during the chewing of gum vs. paraffin tablets (whole saliva 5.18 vs. 2.99 ml/min, parotid saliva 0.83 vs. 0.42 ml/min). Conversely, during final chewing periods, parotid flow rates, pH, and titrated pH were significantly higher during paraffin chewing. When comparing the stimuli, parotid protein output was higher initially during gum chewing, but in the final period paraffin chewing elicited the higher output. It was concluded that the clinical test of paraffin chewing gives a good estimate of the expected whole saliva response to chewing-gum. Furthermore, extended chewing of paraffin tablets seemed to influence parameters of parotid saliva positively.