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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2009.09.024 Byline: P. Pittayapat (a)(b), P. Thevissen (a), S. Fieuws (c), R. Jacobs (d), G. Willems (a) Keywords: Forensic odontology; Dental identification; Hand-held dental X-ray units; Radiological image quality Abstract: Recently, different portable hand-held and battery-powered dental X-ray units have become available. Especially for forensic odontological purposes, they offer diverse advantages such as for use in disaster areas and crime-scene locations as also in autopsy rooms and mortuaries. For any application, the most important feature of these hand-held devices is the delivered image quality. The aim of this study is to evaluate the radiographic image quality acquired by two portable X-ray devices in combination with two types of image receptors and to compare the findings with the image quality of a standard intra-oral X-ray device. Eleven samples consisting of eight teeth, two dry skeletal specimens and one formalin-fixed mandible part were mounted on blocks for standardised (re)positioning. Radiological images were acquired with two hand-held (AnyRay.sup.[R] 60kVp, 0.02-4.00mAs and NOMAD.sup.[R] 60kVp, 0.023-2.277mAs) and one wall-mounted (MinRay.sup.[R] 60/70kVp 0.14-22.4mAs) X-ray device combined with two image receptor systems (VistaScan.sup.[R] phosphor storage plate (PSP) and SIGMA.sup.[R] M CMOS Active Pixel technology sensor). The effect of X-ray source-to-object distance (SOD) was checked at 20cm in conjunction with object to image receptor distances (OIDs) of 0.8 and 2.5cm. For each parameter setup, the exposure times were run from low till high. An expert consent statement was achieved by agreement of four expert observers selecting the optimal images based on a developed four point quality rating system. Next, a selection of the images was assembled in a set of 198 observation screens and scored by seven observers. The observation screens were designed to compare observer scores, relations between devices, receptors and OIDs and images obtained from the different devices at equal exposure levels (mAs). All results were statistically analysed. Radiological image quality was significantly higher for phosphor plate compared with the CMOS digital receptor system (p Author Affiliation: (a) Biomedical Sciences Group, Department of Dentistry, Oral Pathology and Maxillofacial Surgery, Section Forensic Odontology, Katholieke Universiteit Leuven, Kapucijnenvoer 7, B-3000 Leuven, Belgium (b) Radiology Department, Faculty of Dentistry, Chulalongkorn University, Henri-Dunant Road, Bangkok 10330, Thailand (c) Biomedical Sciences Group, Department of Public Health, Leuven Biostatistics and Statistical Bioinformatics Centre (L-BioStat), Katholieke Universiteit Leuven, Kapucijnenvoer 35, 3000 Leuven, Belgium (d) Biomedical Sciences Group, Department of Dentistry, Oral Pathology and Maxillofacial Surgery, Oral Imaging Center, Katholieke Universiteit Leuven, Kapucijnenvoer 7, 3000 Leuven, Belgium Article History: Received 3 October 2008; Revised 27 September 2009; Accepted 30 September 2009

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2009.04.002 Byline: Julie C. Mitchell (a), Graham J. Roberts (a), Ana Nora A. Donaldson (b), Victoria S. Lucas (a) Keywords: Dental age assessment; Meta-analysis Abstract: The purpose of this study was to determine reference data for dental age assessment (DAA) for the 16 year threshold in British caucasians. Author Affiliation: (a) Department of Paediatric Dentistry, King's College Dental Hospital and Institute (KCDI), Bessemer Road, London SE5 9RS, United Kingdom (b) Biostatistics Unit, KCDI, United Kingdom Article History: Received 3 November 2008; Revised 16 March 2009; Accepted 1 April 2009

One of the difficulties that has prevented Wilson bands, internal defects of enamel growth, from achieving maximum usefulness as indicators of stress in bioarchaeological studies is the inaccuracy of the methods for determining ages of defect occurrence. This study tests a technique that uses microstructural growth markers of enamel to establish the chronology of Wilson bands in deciduous teeth. A sample of 274 teeth from 127 sub-adults from an Imperial Roman necropolis was sectioned and examined under a microscope. The sample ranged in age at death from birth to 13 years. Sixty-four teeth from 50 individuals were found to have 447 Wilson bands in total. Of those contributing multiple teeth to the sample, 13 individuals had at least one Wilson band in each of two teeth that could be identified as having been formed co-evally. These provided the basis for testing the methodology. Paired t-tests found no significant differences between the chronologies of matched pairs in the two teeth, with mean ages from each differing by less than 1 day. The authors propose a hypothesis that explains the development of Wilson bands, and classifies them within the context of other features of enamel. The most important implications arising from this paper are: 1) aging methods using microstructural growth markers can be applied to deciduous teeth; 2) physiological stressors leave different traces in enamel, depending on severity and time of occurrence relative to total crown development; 3) no threshold level exists; all physiological stress will leave a record; 4) therefore, no minimal definition of a Wilson band can be delineated that recognizes all such events; 5) implying that studies using them will only identify minimum rates of occurrence. KEY WORDS accentuated striae; Wilson bands; chronology; deciduous teeth; microstructural growth markers

Standard methods should be applied to the identification of deceased individuals using forensic dentistry. All examinations should be conducted under the authority and guidance of a coroner or medical examiner. Photographs, dental records and medical records of the deceased prior to death should be obtained if possible, and photographs of dental evidence both before and after cleaning should be taken. The jaw or other structures should be removed carefully so as to avoid damage to the surrounding tissue and bones and only after obtaining permission from the coroner. A verbal description of the evidence should be given in addition to a written record, and the universal numbering system for the teeth should be used. Dental impressions and X-rays should be taken. These should be compared with impressions and X-rays taken prior to death and a positive, possible or negative identification should be made.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2009.12.009 Byline: J.W. Chen, J. Guo, J. Zhou, R.K. Liu, T.T. Chen, S.J. Zou Keywords: Dental age; Panoramic radiography; Demirjian's method; Forensic Anthropology Population Data Abstract: Age estimation plays an important role in forensic medicine and orthodontics. Dental maturity, expressed as dental age, is one of the common indices for age estimation. Demirjian's method, first described in 1973 and based on a large number of French-Canadian samples, is one of the most widely used methods for dental age assessment. The aim of this study is to evaluate the applicability of Demirjian's method for dental age estimation in western Chinese children. Digital panoramic radiographs of 445 children of western Chinese origin, ranging from 8 to 16 years old, were assessed in Demirjian's method. The dental maturity scores (DMSs) and dental ages of all the subjects were calculated by a single observer. The dental ages were compared to the chronological ages with a paired t-test. The general trend in this research showed that the western Chinese children demonstrated a more advanced dental age compared to French-Canadian children as previously presented by Demirjian. The mean difference in each age group between the dental age and chronological age ranged from 0.0071 to 1.2500 years in girls and from -1.0000 to 1.3000 years in boys. The standards of dental age assessment provided by Demirjian for French-Canadian children may be not suitable for western Chinese children. As a result, specific standards of dental age assessment should be established for this population. Author Affiliation: State Key Laboratory of Oral Diseases and Department of Orthodontics, West China College of Stomatology Sichuan University, Chengdu 610041, China Article History: Received 7 November 2008; Revised 22 November 2009; Accepted 4 December 2009

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2009.01.004 Byline: Masaki Yoshida (a), Yoichi Hanaoka (b), Tamiyuki Tsuzuki (c), Asao Ueno (a), Tetsuya Takagi (a), Kaori Iwahara (c), Mamoru Yasuda (d), Yoshinobu Sato (a), Kiyoshi Minaguchi (b) Keywords: Forensic odontology; Dental identification; Small color dental scanner Abstract: Together with X-ray radiography and the description in the dental chart (odontogram), the collection of intraoral images is extremely important in dental identification. Recently, thanks to advances in digital devices for taking images in the oral cavity, problems with developing images and images being lost due to scanning errors have been minimized. However, in corpses where postmortem rigidity has firmly set in and burned bodies where the jaw has to be forced open, it is difficult to open the jaw enough to allow images to be taken. In addition, collection of intraoral images requires skill. Our goal was to determine the efficacy of a newly developed, small-scale color dental scanner in collecting intraoral images. The results showed that it was comparatively easy to obtain an entire image of the oral cavity with even a minimum degree of jaw opening. This should enable even a non-expert to perform oral image collection. Author Affiliation: (a) Department of Legal Medicine, Kyorin University, 6-20-2 Shinkawa, Mitaka-shi, Tokyo 181-8611, Japan (b) Department of Forensic Odontology, Tokyo Dental College, 1-2-2 Masago, Mihama-ku, Chiba-shi, Chiba-ken 261-8502, Japan (c) Center of Legal Medicine of Dentistry, The Nippon Dental University School of Dentistry at Tokyo, 1-9-20 Fujimi, Chiyoda-ku, Tokyo 102-8159, Japan (d) Kawasaki Research and Development Center, Mitutoyo Corp., 1-20-1 Sakado, Takatsu-ku, Kawasaki-shi, Kanagawa-ken 213-8533, Japan Article History: Received 10 December 2008; Accepted 6 January 2009

Detailed descriptions of the dentition of many strepsirhine primate taxa are rare, despite their importance in understanding primate evolutionary biology. While several researchers have provided detailed morphological descriptions of ring-tailed lemur dentition (e.g., Schwartz and Tattersall [1985] Am. Mus. Nat. Hist. Anthropol. Pap. 60:1-100; Tattersall and Schwartz [1991] Am. Mus. Nat. Hist. Anthropol. Pap. 69:2-18), there are few studies (e.g., Eaglen [1986] Am. J. Phys. Anthropol. 71:185-201) that present quantitative data on the dentition of this species. Furthermore, prior analyses were based on museum specimens from various populations and locations. We present here quantitative and morphological data on the dentition of a population of wild Lemur catta from Beza Mahafaly Special Reserve, Madagascar. Measurements were made on dental casts (n = 39) taken from living members of this L. catta population. Our analysis indicates that no significant (P [is greater than] 0.05) sexual dimorphism exists for the 30 dental measurements collected. These data support the generalizations (e.g., Plavcan and van Schaik [1994] Evol. Anthropol. 2:208-214; Kappeler [1996] J. Evol. Biol. 9:43-65) that little sexual dimorphism in dentition exists among Malagasy strepsirhines. In addition, the overall patterns of metric variation in this sample compare favorably with patterns seen among other primates, e.g., premolar measurements varying more than molars (e.g., Gingerich [1974] J. Paleontol. 48:895-903). However, there is a degree of intraspecific morphological variation indicated, with one of the morphological traits discussed in other studies as being species-specific for L. catta (absence of [P.sub.4] metaconids) observed to vary between specimens. Because the patterns of variation seen in this sample are from a known breeding population, the data presented here provide an important reference for interpreting and understanding the fossil record. Am J Phys Anthropol 114:215-223, 2001. [C] 2001 Wiley-Liss, Inc. KEY WORDS strepsirhine dentition; primate dental metrics; ring-tailed lemurs

Morphological traits in the deciduous dentition have been understudied compared to their permanent counterparts. Reasons the primary teeth are not as intensely studied include: 1) there is no scoring standard, 2) they are often found in lower frequencies than permanent teeth, and are more subject to wear, and 3) the relationship of development of traits between the deciduous and permanent dentitions is still unknown. This study examines the third problem by comparing frequencies of traits found in both types of teeth within and between two groups. The first sample is from a collection of Pima casts collected by the Dahlbergs approximately 50 years ago. The second is ah archaeological Nubian sample dating primarily to the Meroitic period (ca. 400BC-350AD). Twelve comparable crown traits were examined on fifty individuals with deciduous teeth and fifty individuals with permanent teeth from each group. The primary teeth were scored using a combination of visual and written descriptions based on A.A. Dahlberg and K. Hanihara, in conjunction with the Arizona State University Dental Anthropology System (ASU DAS). The permanent teeth were scored according to the ASU DAS. The results of the study indicate that most traits have comparable frequencies but certain traits, including cusp 7, have significant differences. These differences may be a result of the scoring method used, of perhaps a difference in development. With a refinement in scoring procedures and a standard method, the deciduous dentition of subadults can be used in dental morphology research to increase our knowledge of the people we are studying.

Increasingly, studies analyse concentrations and isotope ratios of lead and strontium in archaeological tooth mineral to obtain dietary and mobility information. Unfortunately, there is little data on the fundamental behaviour and homogeneity of lead and strontium in teeth and how this impacts on sample selection and preparation. This study uses core enamel and co-genetic primary crown dentine, neither of which model nor remodel in vivo, from modern and archaeological teeth to investigate lead and strontium behaviour and so inform future sampling strategies. Results demonstrate that isotope ratios of modern enamel and co-genetic crown dentine remain indicative of childhood origin with no evidence for post-eruptive uptake. However, resorbing deciduous roots are dynamic, facilitating lead and strontium incorporation and consequently sensitive to post-formation residence change. Enamel samples from the same tooth, from antimeres and from co-genetic teeth replicate extremely well in modern and archaeological teeth. In particular, enamel strontium reproducibility can surpass that of the analytical standard. Macromorphological tooth preservation is no guide to biogenic strontium or lead isotope integrity. Mature, but not immature, enamel is resistant to diagenesis whether well preserved or not. Dentine is highly susceptible to diagenesis irrespective of preservation state. Formation, mineralization and subsequent ante- and post-mortem behaviour of dentine and enamel are very different; within each tissue there exists age and exposure-dependent changes that, if sampled, may invalidate comparisons between adults and juveniles. Core enamel (all surfaces and enamel-dentine-junction removed) from the histologically simple tooth wall of fully mineralised molars is recommended as the standard archaeological sample.