Use of Superelastic Nitinol and Highly-Stretchable Latex to Develop a Tongue Prosthetic Assist Device and Facilitate Swallowing for Dysphagia Patients.

Mahdis Shayan,Youngjae Chun,Gabrielle Salazar,Woon-Hong Yeo,Neil Gildener-Leapman,Puneeth Shridhar,Jack T Hastings,Jee-Hong Kim,Shinjae Kwon,Moataz Elsisy

doi:10.3390/ma12213555

Abstract

We introduce a new tongue prosthetic assist device (TPAD), which shows the first prosthetic application for potential treatment of swallowing difficulty in dysphagia patients. The native tongue has a number of complex movements that are not feasible to mimic using a single mechanical prosthetic device. In order to overcome this challenge, our device has three key features, including (1) a superelastic nitinol structure that transfers the force produced by the jaws during chewing towards the palate, (2) angled composite tubes for guiding the nitinol strips smoothly during the motion, and (3) highly stretchable thin polymeric membrane as a covering sheet in order to secure the food and fluids on top of the TPAD for easy swallowing. A set of mechanical experiments has optimized the size and angle of the guiding tubes for the TPAD. The low-profile TPAD was successfully placed in a cadaver model and its mobility effectively provided a simplistic mimic of the native tongue elevation function by applying vertical chewing motions. This is the first demonstration of a new oral device powered by the jaw motions in order to create a bulge in the middle of the mouth mimicking native tongue behavior.

Highlights

Millions of Americans suffer from swallowing disorders primarily due to dysphagia every year [1,2]
The superelastic nitinol biomaterials were used for the dynamic backbone in the tongue prosthetic assist device (TPAD)
The tongue plays a significant role in swallowing, through preparing the bolus of food and pushing it posteriorly in order to transfer it from the oral to the pharyngeal phase of swallowing

Summary

Introduction

Millions of Americans suffer from swallowing disorders primarily due to dysphagia every year [1,2]. Dysphagia occurs when the patient cannot properly transfer the food from the mouth to the Materials 2019, 12, 3555; doi:10.3390/ma12213555 www.mdpi.com/journal/materials. Dysphagia occurs when the patient cannot properly transfer the food from the mouth to the esophagus esophagusororfrom fromthe theesophagus esophagustotothe thestomach. Current treatment options for dysphagia strategies forfor head oror body position, Current treatment options for dysphagiainclude: include:postural postural strategies head body position, change bolusvolume volumeor or viscosity, muscle contraction including neuromuscular changein in food food bolus viscosity, tonictonic muscle contraction including neuromuscular electrical electrical stimulation (NMES), sensorial enhancement strategies, and gastrostomy alimentation stimulation (NMES), sensorial enhancement strategies, and gastrostomy tubetube alimentation and and surgery [3]. A widely accepted rehabilitation approach is the Madison Oral. A widely accepted rehabilitation approach is the Madison Oral Strengthening Therapeutic

Methods

Results

Discussion

Conclusion