Effects of tongue right positioner use on tongue pressure: a pilot study

Abstract

The effectiveness of the tongue right positioner (TRP) use on oral and swallowing functions remains unclear. To investigate the effects of TRP use on tongue function in patients with dysphagia. This interventional study included eight participants with dysphagia who visited a university dental hospital. The measurement variables included tongue pressure (TP) as the primary outcome and lip and tongue movements, peak nasal inspiratory flow, and changes in the tongue and suprahyoid muscle regions on ultrasonography as the secondary outcomes. Each participant was asked to use a TRP for at least 8 h every night for 2 months. The measurement variables before and after the intervention were compared using the paired t test and Wilcoxon signed-rank test. TP after intervention (31.5 ± 13.1 kPa) was significantly higher than that before intervention (23.0 ± 13.4 kPa), while other measurement variables did not significantly improve. Numerous exercises have been suggested to improve TP; however, most require patients' adherence to instructions. In contrast, although participants did not perform active exercises, most participants in this study observed an improved TP. Our findings show that TRP can greatly improve TP after 2 months of usage.Trial registration number: University Hospital Medical Information Network Clinical Trials Registry (UMIN000040253, date of first registration: 27/04/2020).

Figure 1

Views of the tongue right positioner. Left: Occlusal view; Right: Posterior view.

Figure 2

Comparison of tongue pressure between baseline and follow-up values for each participant. Each number indicates the participant’s number in Table 1.

Figure 3

Box plots of measurement items with medium or large effect sizes. The left (dark grey) and right (light grey) box plots in each measurement item reveal baseline and follow-up values, respectively. The top and bottom of the vertical line show the maximum and minimum values, respectively, and the box in the middle illustrates the interquartile range. The horizontal line in the middle of the box shows the median value, and the cross mark shows the mean value. TP tongue pressure, ODK oral diadochokinesis, PNIF peak nasal inspiratory flow.