MadSci Network: Anatomy
Query:

Re: How the jaw works

Date: Tue Mar 24 19:10:48 1998
Posted By: Jim Bridger, Faculty, Biology, Prince Georges Community College
Area of science: Anatomy
ID: 890182344.An
Message:

The number of times that a person moves their jaw per day would of course vary greatly by the activities of the person. It would also vary due to what was considered closing the jaw. For instance, every time one swallows, the teeth are slightly clenched. Does that constitute a closing? So, I can't really answer this part of your question.

The other part of your question is also difficult to answer for a number of reasons. Since the 4 muscles that are mainly responsible for chewing (masseter, temporalis, lateral and medial pterygoids) all can vary in their strengths due to useage, genetics etc., it would be only a guess to come up with a figure of so many pounds per square inch of pressure. The act of swallowing for example, causes about 25 pounds of force per square inch to be exerted on the back teeth. The amount of force exerted during the clenching of the mandible would be many times that amount. Incidently, you can feel the masseter and temporalis muscles when you clench your teeth. Feel in the area of your cheek and temple to feel them "bulge" during contraction. The chewing muscles are among the strongest muscles in the body and in carnivorous animals they are leveraged differently so that they are even stronger.


Current Queue | Current Queue for Anatomy | Anatomy archives

Try the links in the MadSci Library for more information on Anatomy.



MadSci Home | Information | Search | Random Knowledge Generator | MadSci Archives | Mad Library | MAD Labs | MAD FAQs | Ask a ? | Join Us! | Help Support MadSci


MadSci Network, webadmin@www.madsci.org
© 1995-1998. All rights reserved.