Comparison of mouth rinsing performance between adults and children using a contactless vital sensing camera.

BACKGROUND: Evaluating mouth rinsing skills is useful for assessing oral function, however current evaluation methods are subjective. OBJECTIVES: This study compared mouth rinsing between adults and children using a contactless camera to capture lip motion. METHODS: The subjects comprised 16 adults and 13 children with no oral dysfunction. A compact vital sensing camera adapted from a Microsoft Xbox One Kinect Sensor® (Kinect) was placed 100 cm from the floor and 120 cm from the subject; 5, 10 and 15 ml of water were used as samples. Participants were instructed to hold the sample in the oral cavity, close the lips and move the sample alternatively left and right for 15 s. Maximum/minimum displacement from the reference plane and rinsing cycle for each sample were analysed by one-way analysis of variance. RESULTS: In adults, there was no significant difference in the maximum/minimum displacement between the left and right sides of the angulus oris due to differences in sample amount. In children, the right maximum significantly differed between the 5- and 15-ml and 10- and 15-ml samples, while the left maximum significantly differed between the 5- and 10-ml and 5- and 15-ml samples. The right minimum significantly differed between the 5- and 10-ml samples, as did the duration of mouth rinsing between the 5- and 15-ml samples. CONCLUSIONS: In children, lip movement and mouth rinsing duration tended to decrease with increasing sample volume. Evaluating lip movement using a contactless vital sensing camera is useful for assessing children's development of oral function.

Relationship between lip motion detected with a compact 3D camera and swallowing dynamics during bolus flow swallowing in Japanese elderly men.

Clinical application of a swallowing function evaluation system that is minimally invasive and enables an objective evaluation is necessary. We constructed a system that can synchronise and analyse lip motion with a three-dimensional (3D) camera and swallowing dynamics with videofluoroscopy (VF) and clarified the relationship between lip movement and swallowing dynamics. A compact 3D camera was adapted to Microsoft XBox One Kinect Sensor® . We examined Kinect's accuracy and repeatability and analysed the highest measurement accuracy and repeatability of the distance between anguli oris muscles. The constructed system simultaneously measured, synchronised and analysed lip motion by Kinect and swallowing dynamics by VF. Fourteen elderly men without dysphagia were included. Barium turbid solution (5, 10, 15 and 20 mL) was used for swallowing. Measurement parameters were the 3D distance between angulus oris displacement (TDDD), swallowing quantity (SQ), oral transit time (OTT), stage transit duration (STD), pharyngeal transit time (PTT) and total swallowing duration (TSD). Statistical analyses were performed. The measurement accuracy and reproducibility were optimum within a 10° horizontal imaging angle at a 120-cm measurement distance. SQ, TDDD, OTT, STD, PTT and TSD showed significant differences, and correlation was found between TDDD and OTT. SQ affected TDDD, OTT, STD, PTT and TSD; OTT could be predicted from TDDD. Improvement in the system and analysis method was considered to enable prediction of swallowing dynamics from body surface movement of the head and neck, including realisation of measurement conditions with higher precision and reproducibility, and from lip motion.