Effects of repeated wet and dry swallows in healthy adult females.

Understanding changes that may occur in the swallow with repetitive use in healthy individuals is a prerequisite to evaluate and treat persons with compromised swallowing. To determine any systematic effect of use on swallow function, we attempted to tax the swallow mechanism in a rigorous sequence of dry and liquid swallow conditions. Oropharyngeal temporal measures were assessed videofluoroscopically for 12 healthy females aged 20-29 during 42 wet and 5 dry swallows. No significant effects were found for any temporal measures over a series of 21 l-mL and 21 cup swallows plus 5 dry swallows, indicating swallow efficiency and safety do not appear to decline over 47 swallows in this young adult population. Additionally, no significant effects were found over the dry swallows or when 1-mL liquid swallows were compared with the dry, indicating dry swallows do not demonstrate significant change over a 5-swallow series due to reduced available saliva. Ability of subjects to perform consecutive dry swallows varied greatly. Results of this study provide normative data regarding multiple, consecutive, wet and dry swallowing in a healthy female population.