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Tim Woodfield
12-08-1997, 02:12 AM
Hi Biomch-L members,

Last week I posted a couple of questions to the list about determining the
stresses experienced in the temporomandibular joint (TMJ) and current finite
element modeling
in this area. Thanks very much for your help, here is a summary of the
replies I received:

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Dr David Hooper wrote:

I did my Ph.D. at the University of Iowa and one my friends was
working on an FE model of the TMJ. His name is Jim DeVocht and has
since finished his degree. I believe his work has been published but
I'm not certain where. Furthermore, I believe that he is currently
at Palmer Chiropractic College in Davenport Iowa. Good luck.

David
Department of Rehabilitation Sciences
University of East London
Romford Road
London E15 4LZ
Phone 0181-590-7000 (4025)
d.m.hooper@uel.ac.uk

**** Thanks to David I managed to track down this article by DeVocht:
- A Study of Control of Disc Movement within TMJ Using Finite Element
Analysis 1996. J Oral Maxillofac Surg; 53(12):1431-1437.****

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Eric Holmgren wrote:

> It seems likely that to obtain the specific information I require for the
> implant, I will need to develop an FE model to simulate the varying load
> conditions experienced at the TMJ, so :
>From my FEA experience, especially in the dental realm, comparing
FEA-generated stress values to that of histological bone stress values is
not always accurate. However, comparing the stress fields of varying
materials and different shapes within the same FEA model to obtain the most
optimum stress field (as compared to other materials) is extremely useful.

> 2. I would also like to hear any opinions on how to obtain a complete
> picture of stress at the condyle. Are max forces exerted on the TMJ only
> during clench? If so, there may be enough information available and no need
> for further FE modeling, or, are forces affected by incisal opening?
I'm not really sure about this, but I would think that not only magnitude
but direction of bite force would play a role too; i.e. using maximum bite
force on a stiff food bolus say on the right side of the mandible.

Just my two cents worth, good luck

Eric P Holmgren

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Steve Levin wrote:

I'm not sure where I read it, but there does not appear to be any
compressive load across the TMJ. It appears that the bones Are suspended
in there muscle tension network just as the teeth are suspended in their
sockets.
Steve Levin
Potomac Back Center
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Thank you very much for these replies. Any futher information is of course
welcome.
Tim
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Tim Woodfield
Institute of Biomedical Engineering
University of Toronto
Home Ph: (416) 536-2304
Office Ph: (416) 978-4995
Office Fax: (416) 978-4317
E-mail: woodfield@ibme.utoronto.ca