Salivary flow rates during relaxing, clenching, and chewing-like movement with maxillary occlusal splints

The purpose of this study was to test the hypothesis that the application of occlusal splints increases the diurnal salivary flow rate both in bruxism patients and in normal subjects. Salivary flow rates in 16 adult volunteers (8 bruxism patients and 8 sex- and age-matched control subjects) were measured with the spitting method. There was no significant difference in the salivary flow rate with or without splints between the control and bruxism groups. In all subjects, the salivary flow rates with splints were significantly higher than those without splints during relaxing, clenching, and chewing-like movement. The salivary flow rate during the chewing-like movement was significantly higher than that during relaxing and clenching, irrespective of splint application. The results suggest that maxillary occlusal splints might stimulate salivary secretion, particularly during chewing-like movement, in both bruxism patients and normal subjects.