NCJ Number
145903
Journal
Journal of Forensic Sciences Volume: 38 Issue: 6 Dated: (November 1993) Pages: 1383-1390
Date Published
1993
Length
8 pages
Annotation
This examination of the location of the neonatal line in 173 primary teeth from 43 children shows significant differences among preterm, term, and postterm births.
Abstract
The researchers obtained primary teeth from 21 males and 22 females by advertising in local newspapers for "tooth fairies" whose children were born significantly preterm or postterm. Crowns were identified from anatomical form, embedded in Fiber-Tek resin, and allowed to cure until hard. Labio/bucco-lingual sections approximately 200 microns thick were obtained with a Buehler Isomet low-speed saw fitted with a 3-inch diamond wafering blade. Each longitudinal section was examined under normal and polarized light at 20x magnification for evidence of the neonatal line. Approximately 75 percent of the neonatal lines that lie beyond 2SD of the mean location of the line in term births were from children born outside 38 to 42 weeks gestation. The duration of pregnancy accounted for about 36 percent of the variation in location of the neonatal line in nonterm births. Based on the small proportion of nonterm births whose neonatal line was located beyond 2 SD of the mean location of the neonatal line in term births, the authors estimate that this technique will provide individualizing information in approximately 3 percent of immature skeletonized remains in a forensic context. The relative timing of prenatal and postnatal pathological striae in the enamel of primary teeth can be evaluated in terms of the variation, documented in this study, in the location of the neonatal line due to individual and birth timing differences. Determination of the timing of pathological enamel striae will aid in the identification of both children and adults for whom histological examination of enamel is undertaken. 1 table, 3 figures, and 27 references