Conference Proceedings | J Oral Health Dent. 2018;1(S2):A024 | Open Access

Investigating the Effect of Tablet Size and Shape on Swallowing Using an In Vitro Model

Marconatia M1,2, Rauta S1,2, Burbidgeb A1,2, Engmannb J1,2 and Ramaiolia M1,2

1CPE, Faculty of Engineering and Physical, Sciences, University of Surrey, Guildford, GU2 7XH, UK
2Nestlé Research Center, Route du Jorat 57, 1000 Lausanne 26, Switzerland



Purpose: Dysphagia imposes significant limitations to oral drug therapy. The conditions leading the acceptance of different tablet sizes and shapes lack mechanistic understanding and rely on practitioner's experience. An in vitro test is proposed as a tool to quantitatively assess the role of tablet size and shape in the oral phase of swallowing.
Methods: The in vitro setup allows to study the tablet and bolus attributes at different simulated tongue forces in a geometry reproducing the key features of the oral cavity. The evolution of the velocity of the bolus, the oral transit time and the relative position of the tablets within the bolus were quantified in vitro from high speed camera recordings.
Results: The swallowing performance of tablets decreases with their cross sectional area in the direction of swallow. This effect was accentuated by low applied tongue driving force and thin suspending liquid vehicles. The relative position of the tablets in the bolus evolved during the swallow highlighting a slower flow of the smallest and largest tablets compared to the bolus flow. Finally, results show that a single tablet flows faster than several smaller tablets of equivalent total volume.
Conclusions: These results highlight the important interplay of tablet size, shape and liquid viscosity and the meaningful contribution that in vitro methods can provide to pre-screening tablet design before in vivo evaluation.