| Mechanical impact of incisor loading on the primate midfacial skeleton and its relevance to human evolution. | |
| | |
MedLine Citation:
|
PMID: 20235317 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
The midfacial skeleton in the human lineage demonstrates a wide spectrum of variation that may be the consequence of different environmental and mechanical selective pressures. However, different facial configurations may develop under comparable selective regimes. For example, the Neanderthal high and projected face and the Inuit broad and flat face are hypothesized to be the consequence of (1) life in a cold climate, and (2) excessive paramasticatory stresses focused on the anterior dentition. In this study, the second of these two hypotheses is tested using finite element analyses of a monkey skull. Results indicate that incisor loading induces heavy stress in the anterior midface of macaques. Additional analyses using incremental increases in the anteroinferior tilt of the skull to simulate different magnitudes of facial projection revealed that comparable muscular force generates less stress in a less-projected face. However, the findings of our final analyses, which attempted to combine biting with the incisors and pulling with the hands, differed from the analyses that mimicked only incisor loading (without any sort of anterior pulling component). These findings suggest that shortening the face may be the most effective way to compensate for anterior dental loading but not necessarily offset the forces incurred when using the anterior dentition as a vice for various paramasticatory behaviors. Although Neanderthals may have frequently loaded their anterior dentition, countervailing selection pressures, such as the inclusion of tough foods in the diet that demanded molar grinding, may have selected for a longer face with a lower load- to lever-arm ratio. |
| | |
Authors:
|
Qian Wang; Barth W Wright; Amanda Smith; Janine Chalk; Craig D Byron |
Related Documents
:
|
2233437 - Stress and hypertension--a critical review. 12111287 - Influence of time pressure and verbal provocation on physiological and psychological re... 10415947 - Excess catecholamine syndrome. pathophysiology and therapy. 17893637 - Morphological and biomechanical aspects of vulnerable coronary plaque. 5020437 - Failure to demonstrate a humoral mechanism in the antinatriuresis of acute caval constr... 9277467 - Cardiovascular responses to glutamate stimulation of diagonal band of broca. |
Publication Detail:
|
Type: Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, Non-P.H.S. |
Journal Detail:
|
Title: Anatomical record (Hoboken, N.J. : 2007) Volume: 293 ISSN: 1932-8494 ISO Abbreviation: Anat Rec (Hoboken) Publication Date: 2010 Apr |
Date Detail:
|
Created Date: 2010-03-25 Completed Date: 2010-07-07 Revised Date: - |
Medline Journal Info:
|
Nlm Unique ID: 101292775 Medline TA: Anat Rec (Hoboken) Country: United States |
Other Details:
|
Languages: eng Pagination: 607-17 Citation Subset: IM |
Copyright Information:
|
(c) 2010 Wiley-Liss, Inc. |
Affiliation:
|
Division of Basic Medical Sciences, Mercer University School of Medicine, 1550 College Street, Macon, GA 31207, USA. wang_q2@mercer.edu |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Animals Biomechanics Evolution* Facial Bones / anatomy & histology* Finite Element Analysis Fossils Humans Incisor / physiology* Macaca fascicularis / anatomy & histology Male Models, Anatomic Primates / anatomy & histology* Software Stress, Mechanical |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: The Effect of Early Hominin Occlusal Morphology on the Fracturing of Hard Food Items.
Next Document: Microanatomical Assessment of Nasomaxillary Suture Patency.