Age estimation and the developing third molar tooth: an analysis of an Australian population using computed tomography

The third molar tooth is one of the few anatomical sites available for age estimation of unknown age individuals in the late adolescent years. Computed tomography (CT) images were assessed in an Australian population aged from 15 to 25 years for development trends, particularly concerning age estimation at the child/adult transition point of 18 years. The CT images were also compared to conventional radiographs to assess the developmental scoring agreement between the two and it was found that agreement of Demirjian scores between the two imaging modalities was excellent. The relatively wide age ranges (mean ± 2SD) indicate that the third molar is not a precise tool for age estimation (age ranges of 3-8 years) but is, however, a useful tool for discriminating the adult/child transition age of 18 years. In the current study 100% of females and 96% of males with completed roots were over 18 years of age.     

Human dental age estimation by calculation of pulp-tooth volume ratios yielded on clinically acquired cone beam computed tomography images of monoradicular teeth

Abstract: Secondary dentine is responsible for a decrease in the volume of the dental pulp cavity with aging. The aim of this study is to evaluate a human dental age estimation method based on the ratio between the volume of the pulp and the volume of its corresponding tooth, calculated on clinically taken cone beam computed tomography (CBCT) images from monoradicular teeth. On the 3D images of 111 clinically obtained CBCT images (Scanora^®3D dental cone beam unit) of 57 female and 54 male patients ranging in age between 10 and 65 years, the pulp–tooth volume ratio of 64 incisors, 32 canines, and 15 premolars was calculated with Simplant^® Pro software. A linear regression model was fit with age as dependent variable and ratio as predictor, allowing for interactions of specific gender or tooth type. The obtained pulp–tooth volume ratios were the strongest related to age on incisors.     

Age-at-death estimation by pulp/tooth area ratio in canines: study of a 20th-century Mexican sample of prisoners to test Cameriere's method

Accurate age estimation has always been a problem for forensic scientists, and apposition of secondary dentine is often used as an indicator of age. Cameriere et al. studied the pulp/tooth area ratio by peri-apical X-ray images of the canines, to observe the apposition of secondary dentine. The present study examines the application of this technique in a Mexican identified sample coming from the Department of Physical Anthropology of the INAH, at Mexico City. The main aim of this work is to test the reliability of this method in a skeletal sample of a specific population, different from the samples used for its development. The obtained regression model explained 96.2% of total variance (R(2) = 0.962) with a standard error of estimate of 1.909 and a standard deviation of 1.947. These results demonstrate great reliability and that the age/secondary dentine relationship is not variable in this specific population.     

Three-dimensional modeling of the various volumes of canines to determine age and sex: a preliminary study

Canines are usually used in anthropological and forensic sciences for sex and age determination. The best methods to estimate age are based on secondary dentine apposition, evaluated from periapical X-rays. The aim of this study was to propose a new method of sex and age estimation using 3D models to obtain more precise predictions using tooth volumes. Fifty-eight dental CT scans of patients aged 14-74 with a well-balanced sex ratio composed the sample. One hundred and thirty-three healthy canines were modeled (Mimics 12.0). The sample was divided into a training sample and a validation sample. An age formula was determined using the "pulp volume/tooth volume" ratio. Sex prediction was adjusted with total volumes. Applying the equations to the validation sample, no significant difference was found between the real and predicted ages, and 100% of the sex predictions were correct. This preliminary study gives interesting results, and this method is worth being tested on a larger data sample.     

广东省6～15周岁汉族人牙龄的研究

目的研究广东省6～15周岁人群牙齿钙化的规律,建立根据牙齿钙化程度推断未成年人年龄的方法。方法观测2 710例（男性1 363例,女性1 347例）广东省6～15周岁汉族人全口曲面断层影像片,对其下颌牙齿钙化程度进行评分分级,所得数据经SPSS软件统计分析,建立根据牙齿钙化程度推断年龄的方程,并以100例（男60例、女40例）研究外样本进行盲测。结果数据统计显示,两侧同名牙钙化评分分级值的差异无显著性意义（P〉0.05）,而性别间差异有显著性意义（P〈0.05）;下颌单侧8颗牙齿的钙化评分分级值与年龄相关系数（r）女性为0.552～0.759,男性为0.672～0.838;所建回归模型拟合优度（R2）均在0.7以上,估计值标准误男性为0.91～1.11岁,女性为0.92～0.98岁;盲测推测年龄与真实年龄平均误差男性为0.429±0.282岁、女性为0.399±0.252岁。结论本研究所建方法推断结果准确可靠,可用于广东地区6～15周岁人群年龄推断。     

中国汉族6-18周岁男性牙齿生长发育的年龄研究

目的研究牙齿钙化程度与年龄的关系,建立利用牙齿钙化程度推断中国汉族6～18周岁男性年龄的办程。方法通过对6568名6～18周岁汉族男性全口曲面断层影像上牙齿的钙化程度进行评分;将分级值及其对应年龄输入SPSS软件进行分析,建立推断年龄的方程模型;从研究样本外随机抽取已知年龄的样本160例进行卣测,,结果同名牙齿钙化评分值侧别间秩合检验结果P〉0．05;下颌左侧恒牙钙化评分值与年龄相关分析结果r值均存0．7以上,下颌同名牙间相关系数r均在0．9以上;所建回归模型拟合优度R^2=0．828,估计值标准误为1．23岁;阿测平均洪差为0．423±0．269岁。结论本研究所建立的方法准确可靠,可用于中国汉族6～18周岁男性人群的年龄推断。     

肋软骨分析检验技术在法医学中的应用

传统法医人类学对肋软骨的分析检验仅限于形态学检验.近年来,法医影像学以及分子遗传学的发展丰富了人类肋软骨的分析检验技术,并且已经能够运用于法医学实践中.本文从肋软骨的组织学特性入手,综述了近年来肋软骨在法医人类学性别判定、年龄推断等方面的研究进展,以期为同行提供借鉴和参考.     

Accounting for Future Generations: Intergenerational Equity in Australia1

Australian governments have published three intergenerational reports since 2002. In line with a general international trend these reports pointed to a problem said to arise from an ageing population which exposes Australia to the risk of a future major fiscal crisis. In this article we argue that by failing to use a generational accounting framework, the reports privilege the elderly at the expense of young people. Added to this, they fail to engage any discussion of intergenerational equity defined as distributive fairness and justice. In this article we explore the value of various approaches to intergenerational justice, focusing on the Principle of Intergenerational Neutrality derived from Rawls' theory of justice. We argue that this does not work as well from a policy point of view as Sen's freedom‐as‐capabilities approach. We conclude that linking Sen's approach to justice to a generational accounting will enable governments to address future issues of equity.     

论相对刑事责任年龄承担责任范围的标准

我国《刑法》第17条第2款规定:"已满14周岁不满16周岁的人,犯故意杀人、故意伤害致人重伤或者死亡、强奸、抢劫、贩卖毒品、放火、爆炸、投放危险物质罪的,应当负刑事责任。"对于这8种犯罪是指犯罪行为还是具体罪名,刑法学界展开了激烈的争论,大体上有罪行说、罪名说两种观点。相对刑事责任年龄承担责任范围的标准具有不确定性,对于相对刑事责任年龄承担刑事责任的范围标准不能一概而论,应该具体问题具体分析。因此在罪行说和罪名说的基础上引入附条件的刑事责任年龄制,对于完善相对刑事责任年龄人承担责任范围的标准具有一定意义。     

Radiographic evaluation of third molar development in relation to chronological age among Turkish children and youth

A sharp increase in forensic age estimation of living persons has been observed in recent years. However, ethnic populations residing in different countries have been insufficiently analyzed. According to 2004 data compiled by the Essen-based Turkey Research Center, there are 3.8 million Turkish people living abroad, and 3.2 million of them reside in European Union countries. Despite the high number of Turks living abroad, little is known about third-molar development for forensic application in this population. Hence, it was considered worthwhile to determine the developmental stages of the third molar in a group of Turkish population, to assess chronological age estimation based on the developmental stages, and to compare third molar development according to sex, age and location. Orthopantomograms of 1134 Turkish patients, ages 4-20 years were examined and third-molar developmental stages were evaluated based on Demirjian's classifications. Orthopantomograms were scored by two different observers, and Wilcoxon matched-pairs signed-ranks test used to test intra- and inter-observer reliability revealed a strong agreement between both intra- and inter-observer measurements. Linear regression analysis was performed to correlate third-molar development and chronological age, and further statistical analysis was performed to determine the relation between sex, age and location. Results showed a strong linear correlation between age and molar development (males: r(2)=0.57; females: r(2)=0.56). Mineralizations of left and right third molars were compared using Wilcoxon tests, and no statistical differences were found. No significant differences were found in third-molar development between males and females. Mandibular third molar crypt formation was observed in 2.4% of patients at age seven and maxillary third molar crypt formation was observed in 1.3% of patients at age seven. A strong correlation was found between third-molar development and chronological age. Among the Turkish population, third molar crypt formation is observable at as early as 7 years in both the mandible and maxilla. Agenesis can be determined conclusively if no radiolucent bud is present by age 14.