Biomechanics Activity Analysis -- Brushing My Teeth

Every morning I wake up and brush my teeth, because I value having good hygiene. For this activity, I start by standing in front of my sink with my arms in a relaxed position by the sides of my body. When I reach for my toothbrush with my left hand my left elbow is in an extended position and my shoulder slightly flexed. I will use coordination and grasping methods in order to pick up the toothbrush; activating flexion in the hand joints, while having abduction of my thumb to hold the toothbrush in place. After I successfully have hold of my toothbrush I use my right arm to reach for the bottle of toothpaste and maintain balance of my trunk and lower limbs. When I reach for my toothpaste my right elbow is in an extended position and my shoulder slightly flexed. I will use grasping methods in order to pick up the toothpaste, activating flexion in the hand joints, while having abduction of my thumb in order to squeeze the bottle. To make sure my toothpaste goes onto the bristles of the toothbrush I will use proper coordination and proprioception. During the actual task of brushing my teeth there is continued palmar grasp of the toothbrush, flexion of both the shoulder and elbow, as well as radial deviation at the wrist that is needed to perform the correct circular motions.

The actions of brushing my teeth all occur in the sagittal plane with the correlation of the frontal axis. The osteokinematic movements of brushing my teeth occur in an open kinematic chain that come from the concentric movement of the prime movers. The prime movers used to create the brushing motion are the biceps brachii, triceps brachii, deltoid, and teres minor. The prime movers used when reaching and grabbing the toothbrush and toothpaste are the biceps brachii, brachioradialis, and bracialis. The arthrokinematic movements of brushing my teeth occur at the elbow joint, where the ulna is the concave structure that is rolling and gliding on the humerus which is the convex structure.