Tissue contributions to sex and race: Differences in tooth crown size of deciduous molars
- 18 June 2001
- journal article
- research article
- Published by Wiley in American Journal of Physical Anthropology
- Vol. 115 (3) , 223-237
- https://doi.org/10.1002/ajpa.1077
Abstract
This study describes size of constituent deciduous tooth crown components (enamel, dentine, and pulp) to address the manner in which males characteristically have larger teeth than females, and the observation that teeth of American blacks are larger than those of American whites. Measurements were collected (n = 333 individuals) from bitewing radiographs using computer‐aided image analysis. Tissue thicknesses (enamel, dentine, pulp) were measured at the crown's mesial and distal heights of contour. Deciduous mesiodistal molar crown length is composed of about 1/7 enamel, 1/3 dentine, and 1/2 pulp. Details differ by tooth type, but males typically have significantly larger dentine and pulp dimensions than females; there is no sexual dimorphism in marginal enamel thickness. Males scale isometrically with females for all variables tested here. Blacks significantly exceed whites in size of all tissues, but tissue types scale isometrically with blacks and whites with one exception: enamel thickness is disproportionately thick in blacks. While the absolute difference is small (5.56 mm of enamel in blacks summed over all four deciduous molar tooth types vs. 5.04 mm in whites), the statistical difference is considerable (P < 0.001). Aside from enamel, crown size in blacks is increased proportionately vis‐à‐vis whites. Principal components analysis confirmed these univariate relationships and emphasizes the statistical independence of crown component thicknesses, which is in keeping with the sequential growth and separate embryonic origins of the tissues contributing to a tooth crown. Results direct attention to the rates of enamel and dentine deposition (of which little is known), since the literature suggests that blacks (with larger crowns and thicker enamel) spend less time in tooth formation than whites. Am J Phys Anthropol 115:223–237, 2001.Keywords
This publication has 65 references indexed in Scilit:
- Small tooth sizes in a nineteenth century South Carolina plantation slave seriesAmerican Journal of Physical Anthropology, 1989
- Human and mouse amelogenin gene loci are on the sex chromosomesGenomics, 1989
- The developmental field concept in clinical geneticsThe Journal of Pediatrics, 1982
- A Simple Method of Multiple Comparisons of MeansJournal of the American Statistical Association, 1978
- An analysis of developmental fieldsDevelopmental Biology, 1970
- Density Patterns in EnamelCaries Research, 1967
- ALLOMETRY AND SIZE IN ONTOGENY AND PHYLOGENYBiological Reviews, 1966
- Blood factors and morphology of the Negroes of James Island, Charleston, S. C.American Journal of Physical Anthropology, 1964
- Studies of the Mammalian Dentition.–Differentiation of the Post‐canine DentitionJournal of Zoology, 1939