Investigating the relation between hyposalivation and mucosal wetness

Objective: to validate the measurement of mucosal wetness in the diagnosis of dry mouth and examine the correlation between mucosal wetness and salivary flow rate. Method: 100 dry mouth patients and 50 healthy control subjects were included on the study. Measurement of mucosal wetness using a Periotron® 8000 was performed at four sites inside the mouth; Anterior Hard Palate (AHP), Buccal mucosa (BUC), Anterior Tongue (AT), Lower Lip (LL). Unstimulated Whole Mouth (UWM) salivary flow rate was also measured. In order to validate the reproducibility of the method 10 healthy subjects had their mucosal wetness and UWM flow rate measured 10 times over 10 visits (5 mornings and 5 afternoons). The relationship between mucosal wetness and UWM flow rate was determined. Means of wetness at different surfaces were compared using ANOVA and Students t tests. Results: The wettest site was AT (32 µm ± 2.5) and, like the other sites, its wetness was significantly correlated with UWM salivary flow rate (0.55, p=<0.01value). AHP was the driest site (7 µm ± .72). All sites showed a decrease in wetness in patients versus controls (eg. BUC: 15 µm ± 5.7, 32 µm ± 2.3). Anterior tongue mucosal wetness was best correlated with UWM flow rate. The AT, BUC, and LL showed decreases wetness even in patients with UWM flow rate of > 0.2 ml/min. Conclusion: Mucosal wetness is positively correlated with UWM flow rate and can be reliably used to directly monitor the mucosal surfaces of dry mouth patients.