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Showing posts from May, 2007

Unilateral vs bilateral biting

Well, I haven't really had anything to post for awhile but I came up with an idea today.

Another one of my introductions into bite force analyses. This time, it's a relatively old but very well cited study by Jeff Thomason et al. (1990). This study is usually cited for the isometric stress values in jaw adductor muscles. What this means, is that when muscles contract, the individual fibres exert a certain amount of stress (force over a unit area). Thomason et al. (1990) showed that the mean muscle stress was 317 kPa which was well within the range of 147 - 392 kPa obtained for other vertebrates in a previous study (Carlson and Wilkie 1974).

The significance of these results is that they allow us to calculate muscular contractile forces from the physiological cross-sectional areas (PCSA) of muslces. Since stress is force over unit area, if the total area is known, then force can be calculated. Now, since stress value seems to be within a known range, we can multiply the stress va…