Dental and skeletal imaging in forensic age estimation : disparities in current approaches and the continuing search for optimization

Medical imaging for forensic age estimation in living adolescents and young adults continues to be controversial and a subject of discussion. Because age estimation based on medical imaging is well studied, it is the current gold standard. However, large disparities exist between the centers conducting age estimation, both between and within countries. This review provides an overview of the most common approaches applied in Europe, with case examples illustrating the differences in imaging modalities, in staging of development, and in statistical processing of the age data. Additionally, the review looks toward the future because several European research groups have intensified studies on age estimation, exploring four strategies for optimization: (1) increasing sample sizes of the reference populations, (2) combining single-site information into multifactorial information, (3) avoiding ionizing radiation, and (4) conducting a fully automated analysis

Bias and accuracy of age estimation using developing teeth in 946 children

Developing teeth are used to assess maturity and estimate age in several disciplines. The aim of the study was to determine which of the most well known dental age estimation methods was best at estimating age. The target sample of dental radiographs ( N = 946, ages 3–16) was described by Maber et al. (Forensic Sci Int 159 ( 2006 ) S68–S73). Seven mandibular permanent teeth (I 1 –M 2 ) were assessed, and dental age was calculated using four dental maturity scales and fifteen methods that use data for individual teeth. The mean difference between dental age and real age was calculated (bias) as well as several other measures of accuracy (mean/median absolute difference, percentage aged to within six months and to within 10% of real age). Most methods estimated age with significant bias and standard deviation of bias ranged from 0.86 to 1.03 years. Analysis by age group showed most methods over-aged younger children, and considerably under-aged older children. The method that performed best was the dental maturity scale of Willems et al. (J Forensic Sci 46 ( 2001 ) 893–895) with bias of −0.14 ± 0.86 years ( N = 827), mean absolute difference of 0.66 years, 71% aged to 10% or less of age, and 49% aged to within six months. Two individual teeth, P 2 and M 2 , estimated age with bias not significantly different to zero for most formation stages using methods based on a large reference sample (L9a Demirjian stages) and a uniform age distribution (N25a Moorrees stages). Standard deviation of bias was least for early crown stages and most for late root stages. Methods that average ages for individual teeth improve if schedules for ‘mean age entering a stage’ are adjusted for prediction. Methods that directly calculate ‘mean age within stage’ can be improved by drawing from a uniform age distribution. Am J Phys Anthropol, 2010. © 2010 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/78321/1/21349_ftp.pd

The effects of acute and chronic lithium treatment on rat submandibular salivation

OBJECTIVE: Acute and chronic actions of lithium on salivation induced by agonists associated with receptor-linked hydrolysis of membrane inositol phospholipids (carbachol and phenylephrine) and by agonist linked to activation of adenylate cyclase (isoproterenol) were investigated. MATERIAL AND METHODS: In anaesthetized rats, submandibular salivation induced by intravenous injection of carbachol, phenylephrine and isoproterenol, was measured and expressed as volume of fluid (mul) elicited per 100 mg wet weight of each gland per minute. The experiments were repeated after acute and chronic treatment of lithium (7 mg kg(-1)). The results were analysed with unpaired t-test. RESULTS: Chronic, but not acute lithium treatment significantly decreases carbachol- and phenylephrine-induced salivation while isoproterenol-induced salivation was not changed neither after acute nor after chronic administration of lithium. CONCLUSION: The results suggest that hyposalivation during chronic lithium therapy could be mediated by alterations in the phosphatidylinositol cycle and a consequent lack of inositol after agonist stimulation