Tires â Retreading is less expensive than new tires and is a large portion of this cost. Although mere pennies per mile, an average tire can cost over $250 and annual tire expenses can exceed $4,000 ($0.03 per mile), enough to purchase 16 new tires annually, but still not enough to replace every tire of an 18-wheeler.
With the head in a forward position, a passive tensile force is created in the hyoid muscles resulting in hyoid muscle tension, causing the mandible to be depressed and translated posteriorly. The patient is therefore forced to contract the temporalis and masseter muscles to keep the mouth closed.
These extrinsic eye muscles are some of the fastest contracting and most precisely controlled skeletal muscles in the human body and function as Agonist & Antagonists pairs to move the eyeball. 1  Superior and Inferior Rectus Muscles, 2  Lateral and Medial Rectus Muscles,hese muscles are called extrinsic eye muscles because their origin points are outside of the eyeballs (in the orbit) and insertion points are on the outer surface of the Sclera.