Salivary secretion and occlusal force in patients with unilateral cerebral stroke

The purpose of this study was to investigate salivary secretion in unilateral cerebral stroke patients, including the effects of masticatory forces. We compared the volumes of unstimulated and acid-stimulated saliva between 30 patients with unilateral cerebral stroke and 30 age-matched healthy subjects. The volume of whole-mouth salivary secretion was measured by the modified cotton swab method. Occlusal forces were measured with an occlusal force meter in patients/subjects, in groups with normal teeth and dentures, respectively. The volume of unstimulated saliva in stroke patients was significantly lower than that in controls. For subjects with normal teeth, the volume of acid-stimulated saliva and the occlusal force on the hemiplegic side in stroke patients were significantly lower than those in control subjects. For those with dentures, while the volume of unstimulated saliva in stroke patients was significantly lower than that in controls, there were no significant differences in occlusal forces between the two groups. These results suggest that salivary secretion might be reduced in cerebral stroke patients, which might be caused partly by an inability to generate sufficient masticatory force, and which, in turn, might lead to a reduced masticatory-parotid reflex and consequent disuse atrophy of the salivary glands.