Asymmetry, balance and dental macrowear pattern of Yuendumu Aboriginal people. A case study

Gregorio Oxilia, Ottmar Kullmer, Grant Clement Townsend, John Kaidonis, Luca Fiorenza, Stefano Benazzi

Research output: Contribution to conferenceAbstract

Abstract

Objectives: Real symmetry and perfect balance between opposite jaw halves and antagonistic teeth is not the reality in a masticatory system. Research results show that natural asymmetry in our body, skull and jaws is related to non-genetic environmental and individual ontogenetic factors. However, in modern human groups it seems we see an increase of variability in tooth spatial positions and asymmetry compared to non-human primates and most fossil hominins.
Materials and Methods: The sample of Yuendumu Aboriginal people consists of complete maxilla and mandible dental arch 3D models from 19 individuals (young and adult). The analysis was carried out on first molars from all quadrants. Only individuals with M1´s in similar level of wear were selected. Virtual models were oriented identifying a standard plane for mandible and maxilla. Occlusal fingerprint analysis was used to obtain M1 macrowear patterns, and 2D cross section geometry analysis of the jaws was carried out to investigate the purported asymmetry in dental and palatal arch.
Results and Conclusions: A high variability in asymmetry has been observed in both upper dental and palatal arches, correlating with differences in inclinations of upper M1 crowns. Significant values of correlation have been observed in the lower dental arches inclination, likely expressing less plasticity in the mandible than in the maxilla. The wear facet pattern reveals asymmetries, referring to the inclination of the molars between left and right sides.
Discussion: Wear facets are produced by various factors (external and internal) that interact during ontogeny. Our results emphasize the important role played by asymmetry to understand the masticatory function in the context in which teeth erupted, finding their antagonistic position in the system to produce dental macrowear pattern in modern humans. Enlarged asymmetry in our modern masticatory apparatus highly effects loading distribution and functional capability of food reduction.
Original languageEnglish
Publication statusPublished - 2017
EventInternational Symposium on Dental Morphology (ISDM) & 2nd congress of International Association for Paleodontology (IAPO) - Bordeaux, France
Duration: 4 Oct 20177 Oct 2017
Conference number: 17th
https://isdm-iapo-2017.sciencesconf.org/

Conference

ConferenceInternational Symposium on Dental Morphology (ISDM) & 2nd congress of International Association for Paleodontology (IAPO)
Abbreviated titleISDM-IAPO-2017
CountryFrance
CityBordeaux
Period4/10/177/10/17
Internet address

Cite this

Oxilia, G., Kullmer, O., Townsend, G. C., Kaidonis, J., Fiorenza, L., & Benazzi, S. (2017). Asymmetry, balance and dental macrowear pattern of Yuendumu Aboriginal people. A case study. Abstract from International Symposium on Dental Morphology (ISDM) & 2nd congress of International Association for Paleodontology (IAPO), Bordeaux, France.