Skip to main content Accessibility help
×
Hostname: page-component-7c8c6479df-24hb2 Total loading time: 0 Render date: 2024-03-28T09:22:28.879Z Has data issue: false hasContentIssue false

5 - Sexual dimorphism in the primary and permanent dentitions of twins: an approach to clarifying the role of hormonal factors

Published online by Cambridge University Press:  05 May 2013

Daniela Ribeiro
Affiliation:
The University of Adelaide, Australia
Wayne Sampson
Affiliation:
The University of Adelaide, Australia
Toby Hughes
Affiliation:
The University of Adelaide, Australia
Alan Brook
Affiliation:
The University of Adelaide, Australia
Grant Townsend
Affiliation:
The University of Adelaide, Australia
Grant Townsend
Affiliation:
University of Adelaide
Eisaku Kanazawa
Affiliation:
Nihon University, Japan
Hiroshi Takayama
Affiliation:
Keio University, Japan
Get access

Summary

ABSTRACT

This study aims to quantify the amount of sexual dimorphism in primary and permanent tooth crown size in a sample of Australian twins and to explore the role of hormonal factors in human dental development. We hypothesise that the magnitude and patterning of sexual dimorphism within and between the primary and permanent dentitions of the same individuals will reflect associations between the timing of initial stages in the process of odontogenesis and the timing of hormonal surges during pre-natal and peri-natal development. Serial dental models of the primary, mixed and permanent dentitions of 88 males and 91 females from monozygotic and dizygotic same-sex twin pairs were used. Mesiodistal crown diameters (MD), buccolingual crown diameters (BL), crown heights (CH), and intercuspal distances (IC) of all primary teeth and the permanent central incisors, lower lateral incisors, canines, second premolars, first and second molars were measured to an accuracy of 0.1mm using a 2D image analysis system. Mean values, standard deviations, coefficients of variation, percentages of sexual dimorphism, and correlation coefficients were calculated for all variables. Overall, males presented larger tooth crown dimensions than females, with the primary dentition displaying less sexual dimorphism compared with the permanent dentition. Intercuspal distances tended to show the least sexual dimorphism whereas crown heights showed the most, reflecting differences in the timing of formation of these dimensions during odontogenesis. These results are consistent with some hormonal influence during tooth development, but further studies of twins, including opposite-sex dizygotic pairs, are needed to clarify the nature of this hormonal effect.

Type
Chapter
Information
New Directions in Dental Anthropology
Paradigms, Methodologies and Outcomes
, pp. 46 - 64
Publisher: The University of Adelaide Press
Print publication year: 2012

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Save book to Kindle

To save this book to your Kindle, first ensure coreplatform@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about saving to your Kindle.

Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

Find out more about the Kindle Personal Document Service.

Available formats
×

Save book to Dropbox

To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Dropbox.

Available formats
×

Save book to Google Drive

To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Google Drive.

Available formats
×