Estimating striae of Retzius periodicity nondestructively using partial counts of perikymata
Article first published online: 28 FEB 2014
Copyright © 2014 Wiley Periodicals, Inc.
American Journal of Physical Anthropology
Volume 154, Issue 2, pages 251–258, June 2014
How to Cite
McFarlane, G., Littleton, J. and Floyd, B. (2014), Estimating striae of Retzius periodicity nondestructively using partial counts of perikymata. Am. J. Phys. Anthropol., 154: 251–258. doi: 10.1002/ajpa.22501
- Issue published online: 13 MAY 2014
- Article first published online: 28 FEB 2014
- Manuscript Accepted: 14 FEB 2014
- Manuscript Received: 27 AUG 2013
- chronological markers;
- dental development;
- daily cross-striations
Accurate age estimations for enamel formation and the timing of enamel hypoplasia have traditionally only been available through histological analyses of dental thin sections, which is a difficult and destructive process. However, an association between striae of Retzius periodicity, crucial for accurate aging, and the total number of striae in imbricational enamel has been reported in the literature. This means periodicity can be estimated nondestructively but is reliant on all perikymata being visible along the crown surface. Therefore, crowns with worn or damaged surfaces may not be able to be assessed, potentially limiting sample sizes. We tested this relationship in a modern New Zealand sample and investigated whether reliable associations might be identified using only partial perikymata counts from the cervical half of the crown. Using mandibular canines (n = 11), the distribution of perikymata per decile was recorded using high definition replica surfaces. Thin sections of the same crowns were used to assess periodicity histologically along with striae of Retzius distributions. A strong correlation between total striae numbers and periodicity was also identified in our sample. Furthermore, we report strong correlations that allow periodicity to be estimated from perikymata counts using only 10% of crown height when certain deciles are used. Based on these findings, we propose a simple matrix that can be developed for nondestructively estimating periodicity based on the range of perikymata counts in the sixth to ninth deciles. Am J Phys Anthropol 154:251–258, 2014. © 2014 Wiley Periodicals, Inc.