Age Dental Cardoso

Forensic Science International 172 (2007) 17–22 www.elsevier.com/locate/forsciint

Accuracy of developing tooth length as an estimate of age in human skeletal remains: The deciduous dentition
Hugo F.V. Cardoso *
´ ´ Departamento de Zoologia e Antropologia (Museu Bocage), Museu Nacional de Historia Natural, Rua da Escola Politecnica 58, 1269-102 Lisboa, Portugal Received 25 May 2006; receivedin revised form 12 November 2006; accepted 13 November 2006 Available online 14 December 2006

Abstract Dental age assessments are widely used to estimate age of immature skeletal remains. Most methods have relied on fractional stages of tooth emergence and formation, particularly of the permanent dentition, for predicting the age of infants and very young children. In this study, the accuracyof regression equations of developing deciduous tooth length for age estimation (Liversidge et al.) is tested on a sample of 30 Portuguese subadult skeletons of known age at death. Overall the method shows high accuracy and the average difference between estimated and chronological age is between 0.20 and À0.14 years when using single teeth, and 0.06 years, when using all available teeth. However,there is a tendency for the deciduous molars to provide overestimates of chronological age. Results show that age estimates can be obtained within Æ0.10 years with a 95% confidence interval when several teeth are used. Overall between-tooth agreement in age estimates decreases with increasing age but there is less variability of estimates with more teeth contributing to overall mean age. Oneseemingly limitation of this method may be the fact that it was developed by combining the maxillary and mandibular teeth. The other is related to the accuracy with which radiographic tooth length can be used as a valid surrogate for actual tooth length. Nevertheless, the advantages of this metric method surpass the limitations of chronologies based on stages of dental development. # 2006 ElsevierIreland Ltd. All rights reserved.
Keywords: Forensic odontology; Age determination by teeth; Subadults; Tooth length; Deciduous dentition

1. Introduction Dental age assessments have long been considered the best indicators of age at death in immature skeletal remains and particular attention has been devoted to the development and test of methods based on the permanent dentition. However, whendealing with the remains of very young children, the forensic anthropologist or the bioarchaeologist can utilize additional age markers provided by the deciduous dentition. The formation of deciduous teeth begins before birth and is complete by about the fourth postnatal year, thus providing a number of chronological landmarks during this period [1]. Deciduous tooth emergence has been used to estimateage at death of unknown immature skeletons in forensic investigations [2,3] but it relies on the timing of a single, brief event in the process of tooth eruption. In contrast, tooth formation

* Tel.: +351 213 921 823; fax: +351 213 969 784. E-mail address: hfcardoso@fc.ul.pt. 0379-0738/$ – see front matter # 2006 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.forsciint.2006.11.006progresses in a continuous and cumulative way and ends only when the tooth has been completely formed. Although postnatal deciduous tooth formation data is available [4,5] it is somewhat cursory and particularly scarce for the anterior teeth. Additional difficulties with methods that rely on schedules of tooth formation include problems of defining formation stages and subjectivity in identifyingstages such as fractions of the crown [6]. Radiographic assessments of deciduous teeth have an additional problem with difficulty in distinguishing crown-completed stages in radiographs, since deciduous teeth are less opaque than permanent teeth. Quantitative data on dental development offer additional information about deciduous tooth development, can provide more objective methods of age...