Publication Date


Document Type


First Advisor

Orlosky, Frank James, 1943-

Degree Name

M.A. (Master of Arts)

Legacy Department

Department of Anthropology


Chin; Facial expression; Mandible


The growth of the human mandible has been studied extensively, but questions still remain. In this report the expression of the chin in the human mandible is examined. Three potential factors appeared to be of major significance in the evolution of the mental protuberance: the shifting of the alveolar and mandibular components; the reduction in size of the dentition, and the stress of the medial- pulling lateral pterygoid muscles. The significance of each of these factors was tested in this thesis. Radiographic and metric data from 71 laboratory specimens was used. Data were gathered from the mandibles of 56 adults, 10 children, and 5 adolescents. Correlation and partial correlation statistics were used to test three general hypotheses regarding the expression of the chin in relation to the three possible factors in the evolution and development of the chin. The results did not support the shifting or the dental reduction hypotheses. However, mandibular width and symphyseal variables were significantly correlated and the third hypothesis was supported.


Bibliography: pages 50-53.


vi, 53 pages




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