# Characterizing masticatory motion of dogs using optical and electromagnetic motion tracking

## TL;DR

This study uses motion tracking to analyze how beagle dogs chew different foods, revealing patterns that could help in designing better pet food and dental products.

## Contribution

The study is the first to fully characterize masticatory motion in beagles using optical and electromagnetic tracking.

## Key findings

- Beagle dogs exhibit a hinge motion during chewing with minimal horizontal mandible movement.
- Chewing frequency varies with food type, with kibble resulting in the highest chewing frequency.
- Chewing frequency correlates with the force required to fracture the food, but not with food stiffness.

## Abstract

Accurate knowledge of masticatory motion across a variety of food materials is essential for ex-vivo testing and simulation of the food-teeth interaction. Yet, the masticatory motion has never been fully characterized in the domestic dog (Canis lupus), limiting our ability for ex-vivo modelling.

The aim of this study was to characterize masticatory motion among a variety of different foods in beagle dogs using optical and electromagnetic motion tracking.

We confirmed that the masticatory pattern in the beagle is a hinge motion with no clinically meaningful horizontal motion of the mandible. The mouth opening was not significantly difference among different food and treat types regardless of food stiffness and force to fracture of the food, with a mean and standard deviation of 2.51  ±  0.33 (range 1.93–2.95) cm between the canine teeth during chewing. Conversely, frequency of chewing was influenced by food type, with kibbles having a significantly higher peak mean chewing frequency (2.93 Hz) compared to other feeds. Frequency of chewing was linearly correlated to the force to fracture of the food material (p = 0.03, R2 = 0.56), while stiffness of food did not significantly affect peak chewing frequency.

Data from this study can guide ex-vivo modelling of the feed-teeth interaction for product design and testing, especially those that focus on prevention of periodontal disease and dentoalveolar trauma.