Search

The study objective was to assess (a) the effect of a rubbing-application of ethylenediaminetetraacetic acid (EDTA) or citric acid (CA) has on the ultrastructure of surface dentin and (b) the effect of two scanning electron microscopy (SEM) desiccation preparation techniques have on the collagen surface produced. Treatment regions on proximal root surfaces of extracted human teeth were root planned to expose dentin. Cotton pellets soaked in either 30% CA or 24% EDTA solution were rubbed on the treatment region then processed for SEM using one of two desiccation techniques, that is, (a) critically point dried from liquid CO2 (control) or (b) air-dried from tetramethylsilane (experimental). Specimens were coated with gold/palladium and viewed/photographed with an SEM. Specimens of the control groups displayed tufted fibrils (CA > EDTA) with many dentin tubules being partially obscured by overhanging fibrils. Air-dried specimens of both treatment groups displayed a flat intact monolayer devoid of a matted meshwork of fibrous collagen. Discrete fibril "sprigs," emanating from the surface monolayer, were characteristic of the EDTA group only. The rubbing-application of EDTA on dentin produces a tufted fibril surface somewhat similar to that produced by CA. Air-drying desiccation of both resulted in marked distortion with fibril collapse/coalescence of the tufted collagen matrix.

The two forensic disciplines that most often interact with forensic odontology are forensic anthropology and DNA analysis. Although forensic anthropologic analyses seldom lead to a direct identification, it often helps to narrow the search field, which may indirectly lead to an identification. In addition, many anthropologic analyses involve the craniofacial complex, which may often produce information that is relevant to a dental identification. DNA analysis is often interrelated with forensic odontology investigations. Although dental identification is relatively inexpensive, it relies on antemortem dental records for comparative purposes. However, if dental remains are badly fragmented, burned, or incinerated, a dental identification may not be possible. In these situations, DNA identification is often still possible, as long as a DNA profile can be extracted from the remains and reference samples can be obtained. In addition, if DNA is recovered from a human bitemark, it may be tested and compared with potential bite suspects. These DNA results can be compared with bitemark linkages and assist in either eliminating or corroborating possible suspects.

Objectives Though applied in bioarchaeology, dental wear is an underexplored age indicator in the biological anthropology of contemporary populations, although research has been conducted on dental attrition in forensic contexts (Kim et al., 2000, Journal of Forensic Sciences, 45, 303; Prince et al., 2008, Journal of Forensic Sciences, 53, 588; Yun et al., 2007, Journal of Forensic Sciences, 52, 678). The purpose of this study is to apply and adapt existing techniques for age estimation based on dental wear to a modern American population, with the aim of producing accurate age range estimates for individuals from an industrialized context. Materials and methods Methodologies following Yun and Prince were applied to a random sample from the University of New Mexico (n = 583) and Universidade de Coimbra (n = 50) cast and skeletal collections. Analysis of variance (ANOVA) and linear regression analyses were conducted to examine the relationship between tooth wear scores and age. Results Application of both Yun et al. (2007) and Prince et al. (2008) methodologies resulted in inaccurate age estimates. Recalibrated sectioning points correctly classified individuals as over or under 50 years for 88% of the sample. Linear regression demonstrated 60% of age estimates fell within ±10 years of the actual age, and accuracy improved for individuals under 45 years, with 74% of predictions within ±10 years. Discussion This study demonstrates age estimation from dental wear is possible for modern populations, with comparable age intervals to other established methods. It provides a quantifiable method of seriation into “older” and “younger” adult categories, and provides more reliable age interval estimates than cranial sutures in instances where only the skull is available.

The statistical quantification of error and uncertainty is inherently intertwined with ascertaining the admissibility of forensic evidence in a court of law. In the forensic anthropological discipline, the robustness of any given standard should not only be evaluated according to its stated error but by the accuracy and precision of the raw data (measurements) from which they are derived. In the absence of Australian contemporary documented skeletal collections, medical scans (e.g. multislice computed tomography-MSCT) offer a source of contemporary population-specific data for the formulation of skeletal standards. As the acquisition of morphometric data from clinical MSCT scans is still relatively novel, the purpose of this study is to assess validity of the raw data that is being used to formulate Australian forensic standards. Six human crania were subjected to clinical MSCT at a slice thickness of 0.9 mm. Each cranium and its corresponding volume-rendered three-dimensional MSCT image were measured multiple times. Whether differences between MSCT and dry bone interlandmark measurements are negligible is statistically quantified; intra- and inter-observer measurement error is also assessed. We found that traditional bone measurements are more precise than their MSCT counterparts, although overall differences between the two data acquisition methods are negligible compared to sample variance. Cranial variation accounted on average for more than 20× the variance explained by MSCT vs. bone measurements. Similarly, although differences between operators were sometimes significant compared to intra-operator variance, they were negligible when compared to sample variance, which was on average 12× larger than that due to inter-operator differences.

Decomposition is the process by which organic substances are broken down into a much simpler form of matter. This chapter describes decomposition rates and stages, and a description of time since death estimation.

A 62 year-old contemporary white female diagnosed with metastatic carcinoma of the breast was examined after skeletonisation. She never received chemical, hormonal or radiation therapy. Because of the confirmed clinical diagnosis, lack of medicinal intervention, and quality of bone preservation, this specimen provides a comparative standard for metastatic carcinoma and differential diagnosis of idiopathic dry bone pathology. We detail gross and radiographic bone response to this disease and differentially diagnose the skeleton against Langerhans cell histiocytosis and multiple myeloma, conditions capable of modifying bone in characteristic patterns that may mimic metastatic carcinoma. Copyright © 2006 John Wiley & Sons, Ltd.

Amelogenesis imperfecta is a hereditary enamel protein disorder affecting deciduous and secondary crown formation. The prevalence ranges from 1:700 to 1:14,000 depending on the population. These teeth may be hypoplastic, hypomineralized, or hypermineralized and are often discolored, sensitive and caries vulnerable. Patients often present with psychosocial issues due to appearance. Primary teeth are often treated with stainless steel crowns while secondary teeth are treated with full coverage esthetic crowns. The presenting preteen male here was fitted with Snap-On Smile? (www.snaponsmile.com). This treatment option provided cosmetic enhancement of the patient's appearance besides stabilization without altering the primary and secondary dentition during adolescent development.

This study assessed the effect various scanning electron microscopy (SEM) desiccation preparation techniques have on a tufted collagen surface produced using an acid-burnished (rubbed) demineralization application technique. Citric acid- soaked cotton pellets (30%) were burnished on the dentin treatment region, rinsed in water, and then fixed. Four SEM desiccation preparation techniques were employed: (1) air-dried from glutaraldehyde; (2) air-dried from ethanol; (3) critical point dried from liquid carbon dioxide (control); or (4) air-dried from tetramethylsilane. Control specimens all displayed a characteristic tufted fibril surface. In all experimental groups, fibrils collapsed, forming an intact, undulating nondescript surface monolayer. All air-drying SEM desiccation preparation procedures appear to cause artifactual distortion of a tufted dentin collagen surface.

Dental trauma is sudden, unscheduled, and the dentist and staff must be adequately equipped to expeditiously and properly treat the patient to assure the best possible outcome. This paper reviews current dental trauma guidelines to provide the correct treatment protocol to ensure the best prognosis. The case report illustrates the technique of avulsion care, RCT care, and functional splinting in a successful manner.

Edited by John R. Lukacs. 1998. Eugene: University of Oregon Anthropological Papers (Number 54). 447 pp. ISBN 0-87114-060-8. $39.95 (paper).

Requisite to routine casework involving unidentified skeletal remains is the formulation of an accurate biological profile, including sex estimation. Choice of method(s) is invariably related to preservation and by association, available bones. It is vital that the method applied affords statistical quantification of accuracy rates and predictive confidence so that evidentiary requirements for legal submission are satisfied. Achieving the latter necessitates the application of contemporary population-specific standards. This study examines skeletal pelvic dimorphism in contemporary Western Australian individuals to quantify the accuracy of using pelvic measurements to estimate sex and to formulate a series of morphometric standards. The sample comprises pelvic multi-slice computer tomography (MSCT) scans from 200 male and 200 female adults. Following 3D rendering, the 3D coordinates of 24 landmarks are acquired using OsiriX® (v.4.1.1) with 12 inter-landmark linear measurements and two angles acquired using MorphDb. Measurements are analysed using basic descriptive statistics and discriminant functions analyses employing jackknife validation of classification results. All except two linear measurements are dimorphic with sex differences explaining up to 65 % of sample variance. Transverse pelvic outlet and subpubic angle contribute most significantly to sex discrimination with accuracy rates between 100 % (complete pelvis—10 variables) and 81.2 % (ischial length). This study represents the initial forensic research into pelvic sexual dimorphism in a Western Australian population. Given these methods, we conclude that this highly dimorphic bone can be used to classify sex with a high degree of expected accuracy.

In Australia, particularly Western Australia, there is a relative paucity of contemporary population-specific morphometric standards for the estimation of sex from unknown skeletal remains. This is largely a historical artefact from lacking, or poorly documented, repositories of human skeletons available for study. However, medical scans, e.g. MSCT (multislice spiral computed tomography) are an ingenious and practical alternative source for contemporary data. To that end, this study is a comprehensive analysis of sternal sexual dimorphism in a sample of modern Western Australian (WA) individuals with a main purpose to develop a series of statistically robust standards for the estimation of sex. The sample comprises thoracic MSCT scans, with a mean of 0.9 millimeter (mm) slice thickness, on 187 non-pathological sterna. Following 3D volume rendering, 10 anatomical landmarks were acquired using OsiriX(®) (version 3.9) and a total of 8 inter landmark linear measurements were calculated using Morph Db (an in-house developed database application). Measurements were analyzed using basic descriptive statistics and discriminant function analyses, with statistical analyses performed using SPSS 19.0. All measurements are sexually dimorphic and sex differences explain 9.8-47.4% of sample variance. The combined length of the manubrium and body, sternal body length, manubrium width, and corpus sterni width at first sternebra contribute significantly to sex discrimination and yield the smallest sex-biases. Cross-validated classification accuracies, i.e., univariate, stepwise and direct function, are 72.2-84.5%, with a sex bias of less than 5%. We conclude that the sternum is a reliable element for sex estimation among Western Australians.

Positive identification of skeletonized, decomposed, or disfigured victims lacking clinical records is a difficult endeavor. However, videotapes of family and social activities can be analyzed using the frame isolating technique of video image capture by inexpensive means. A rare skeletal Class III malocclusion and dental peculiarities in a decomposing 3-year old lacking a clinical history were compared to videotapes taken of a suspected victim shortly prior to her disappearance. Overlaying transparent dental tracings from digitized skeletal remains onto selected frames of the videotape (and reversing this process) produced the identification and hastened the entire investigation.

Twenty-two years of human identification cases have been analyzed with respect to the development of a forensic anthropology curriculum at the University of Tennessee under William M. Bass. Relationships forged with the State Medical Examiner and lecture programs for national, state and local law enforcement agencies and arson investigators have provided the necessary exposure that ensured the growth of Dr. Bass's caseload and program. Postmortem indicators for assessing time-since-death have been Bass's target research domain. The development of a donated body program with curation of those skeletons promises to keep his research perspective fueled. Finally, the formal establishment of the Forensic Anthropology Center at the University of Tennessee ensures the continued academic commitment to forensic anthropology.