Ergonomic Evaluation and Customized Design of Toothbrush Handle

Toothbrush handles available in the market are classified in adult, junior and baby sizes. As per IS 3387:2004, the length of the handle for these variants is specified. However, the width and thickness of the handle is not specified. As per the standard “The width and thickness of the handle may vary according to the individual design”. The focus of the current work is to design an ergonomic toothbrush handle based on hand anthropometry. This would improve the grip of the handle (user comfort) and enhance oral hygiene. A commercially available toothbrush was taken as reference to find out the optimal parameters of toothbrush handle. Hand anthropometric data of volunteers was collected. The comfort rating of these volunteers was related to the normalized handle sizes. The resulting regression equation was used to find out the optimal handle dimensions. Contact area was measured using both commercially available toothbrush handle and the same toothbrushes with different fabricated handle sleeves. Electromyography activity was recorded for muscle fatigue. The plaque index was also obtained before and after two weeks of using customized toothbrush handle. It was observed that the customized toothbrush handle was comparatively more purposeful. Relevance to Industry. From the results of this study, tooth brush designers, researchers and manufacturers can obtain guidelines for maximising grip comfort based on the hand sizes of users. The results also shows that optimal handle diameter will result in increasing the subjective comfort rating which will further increase the user performance and will lower the risk of muscle fatigue.