Odontometrics

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Odontometrics is the measurement and study of tooth size.[1][2] It is used in biological anthropology and bioarchaeology to study human phenotypic variation. The rationale for use is similar to that of the study of dentition, the structure and arrangement of teeth.

Uses of Odontometrics[edit]

Determining Age[edit]

Linking to the Past by Kenneth L. Feder states that "Dental development...provides a valuable gauge of the level of physical maturity and age." [3] The first set of teeth, or the lower central incisors, does not begin to appear until the infant is approximately six-and-a-half months old. The rest of the baby teeth, which are called deciduous teeth, will then appear “fairly consistently across the species”, until the child is about two-years-old, when the second upper molars appear; at this point in development, there are twenty teeth in all.

From the age of two-and-a-half until about six years, the deciduous teeth maintain stability, until a set of molars (also called “Six Year Molars”) appear in the lower jaw; these are the child’s first permanent teeth. From this point on, for the approximate next twelve years, the rest of the deciduous teeth will be replaced by all of the permanent teeth. Additional permanent teeth will erupt in the back of the mouth in order to enlarge the mouth. When the process of all permanent teeth coming in is over, the adult mouth will have thirty-two teeth.

The “fairly consistent” rate at which deciduous and permanent teeth appear is relevant because it allows an expert to determine the age of the human. According to Feder, based on odontometrics, “the approximate age of a living child or the age at which a deceased child died can be fairly easily and accurately determined based on which teeth are present, the stage of growth of these teeth, and which teeth have yet to erupt into the mouth.”

Determining Sex[edit]

Though, when available, more standard approaches to sex identification are used, in times where the archaeological remains are not completely discovered or preserved, odontometrics are used. Because teeth are “made from the most enduring mineralized tissues in the human body”, they are resistant to many types of destruction, including physical, thermal, mechanical and chemical. According to Marin Vodanović et al., “Sex determination using dental features is primarily based upon the comparison of tooth dimensions in males and females, or upon the comparison of frequencies of non-metric dental traits, like Carabelli's trait of upper molars, deflecting wrinkle of lower first molars, distal accessory ridge of the upper and lower canines or shoveling of the upper central incisors”. When analyzing the teeth, one must also take into consideration the differences in odontometric features between different populations, or one may be lead to a false conclusion in sex determination.[4]

References[edit]

  1. ^ Relethford, John (2009). The Human Species: An Introduction to Biological Anthropology, Glossary. McGraw Hill Online Learning Center. ISBN 0-07-353101-4. Retrieved May 2, 2010. 
  2. ^ Kieser, Julius A. (2008). Human Adult Odontometrics: The Study of Variation in Adult Tooth Size. Cambridge Studies in Biological and Evolutionary Anthropology. Cambridge University Press. ISBN 0-521-06459-7. 
  3. ^ Feder, Kenneth L. (2007). Linking to the Past: A Brief Introduction to Archaeology, Second Edition. Oxford University Press. ISBN 0-19-533117-6. 
  4. ^ "Odontometrics: a useful method for sex determination in an archaeological skeletal population?". Journal of Archaeological Science (in English). 2006-08-02. Retrieved 2012-04-01.