Journal of Dental Research, Vol 65, 1300-1302, Copyright © 1986 by International & American Associations for Dental Research Online Journals
A cinephotographic study of the role of the canine in limiting lateral jaw movement in Macaca fascicularis
C. N. Kay, R. P. Scapino and E. D. Kay
Department of Pediatrics, University of Illinois at Chicago 60612.
Three specimens of Macaca fascicularis were examined to test the hypothesis
that the canines do not restrict lateral masticatory movements in these
animals. The animals were filmed while chewing freely before, shortly
after, and seven weeks after canine removal. Facial markers, viewed from
the lateral plane, allowed for computer tracings of all mandibular
movements. The maximal lateral movement of the mandible was assessed for
each chewing cycle, and means were calculated for each test condition and
animal. These means were compared intra-animal for statistically
significant differences in lateral jaw movement before and after canine
removal. No significant long-term increase in lateral movement was found in
any animal after the removal of its canine teeth. We conclude that, in
accordance with our hypothesis, the lateral movement during mastication did
not increase significantly after removal of the canine teeth in three
specimens of Macaca fascicularis. Therefore, the use of the macaque as a
human model for masticatory studies requires further assessment. This study
reveals that the canine teeth are not as important as previously assumed in
affecting the form of the masticatory cycle in the macaque.
