Analysis of Toothbrushing Motion with High Precision Motion Capture

Fourth Report: Analysis and Comparison of Arm Movement between Dominant and Non-dominant Hand

Abstract

The pen grip is one of the recommended methods for holding a toothbrush, as it allows careful control of movement by the fingers. However, toothbrushing with a pen grip may be difficult for children because of limited dexterity. We evaluated the brushing movements in adults when toothbrushing with their non-dominant hand to simulate the instable movements of children.

Dental hygienists were employed as subjects, and asked to brush the buccal and palatal sides of the right and left upper molars. Toothbrush motion frequency and the joint angles of the shoulder, elbow,and wrist were examined. Furthermore, the motions of the toothbrush and arm during brushing were evaluated and compared between brushing with the dominant and non-dominant hand.

Study conclusions :

1)The peak frequency and effective arm motion while brushing the upper buccal left and palatal right and left molars were different between brushing with the dominant and non-dominant hand.

2)When brushing the upper left molars, a significant difference was noticed for peak frequency and effective arm motion when brushing with the dominant and non-dominant hand.

3)All arm joints must move in a synchronous manner in order to enable reciprocal motion of the toothbrush while brushing with a pen grip.

Our findings suggest that arm motion during tooth brushing with the dominant hand using a pen grip requires a certain level of learning and proficiency, while the coordinated movements of the joints of arm are reflected in reciprocal motion of the toothbrush.