Effect of Tongue-Hold Swallow on Pharyngeal Contractile Properties in Healthy Individuals

Abstract

Tongue-hold swallow (THS) is a swallow exercise in which an individual swallows saliva while holding the anterior portion of the tongue between the front teeth. The effect of THS on pharyngeal contractile vigor is still unclear. The purpose of this study was to quantify THS using high-resolution manometry with a contractile integral analysis. Twenty-two healthy participants performed three different saliva swallow tasks: normal swallow, weak THS (in which the tongue was protruded 1 cm outside the upper incisors), and strong THS (in which the tongue was protruded 2 cm outside the upper incisors). The participants repeated each task twice randomly. Pharyngeal and upper esophageal sphincter metrics, including the pharyngeal contractile integral, were analyzed. Both weak and strong THS enhanced the velopharyngeal contractile integral and peak pressure compared with normal swallow (P < 0.01). THS also prolonged mesopharyngeal contraction (P < 0.01). Holding the tongue anteriorly during swallow requires significant biomechanical changes to pharyngeal contractile properties at the superior and middle pharyngeal constrictor levels; thus, it may serve as a resistance exercise for the muscles that are involved in bolus propulsion.

Keywords: Deglutition; Deglutition disorder; High-resolution manometry; Superior pharyngeal constrictor; Tongue-hold swallow.

Fig. 1

Tongue positions with normal saliva swallow, weak tongue-hold swallow (THS), and strong THS The tongue was protruded 1 and 2 cm outside the upper incisors in weak and strong THS, respectively. The extent of tongue protrusion was adjusted using a transparent scale

Fig. 2

Example of spatiotemporal plots of normal saliva swallow, weak tongue-hold swallow (THS), and strong THS from a single participant, who exhibited differences in velopharyngeal and mesopharyngeal pressure topographies. UES upper esophageal sphincter