A simple technique for age estimation in adult corpses: the two criteria dental method.

A method for age determination of adults from single rooted teeth is presented. It is based on the measurement of two dental features: periodontosis height times 100/root height (P) and transparency of the root height times 100/root height (T). These measurements are made on the labial surface of the entire tooth without section and do not require special equipment or training. The application of multiple regression analysis to a working sample of 306 teeth of known age, sex and race provided the following equation: Age (years) = 0.18 x P + 0.42 x T + 25.53. The mean error between the actual and estimated age was +/- 10 years on the working sample and +/- 8.4 years on a control sample made of 45 forensic science cases. Upper incisors showed a better precision than the other single rooted teeth and accuracy was not sex related. A comparison of the Gustafson and Lamendin methods on a control sample of 39 teeth resulted in an advantage of the latter considering the mean error on the estimation (14.2 +/- 3.4 years for Gustafson versus 8.9 +/- 2.2 for Lamendin). The Lamendin method can be practical interest for any forensic pathologist or dentist as it is fast, easy to use, and reasonably accurate except for cases of individuals under age 40 where other methods must be preferred.     

计算机图像分析应用于牙齿推断年龄方程的研究

应用计算机多元逐步回归对567颗中国人牙齿结构变化进行图像分析、分级并对数转换的数据分析，从而推导出利用牙齿推断年龄的方程。根据适用范围和牙齿类型的不同，从实验组得到的利用单颗牙齿推断年龄方程的估计标准误分别为4．8岁～5．4岁；各方程测试于对照组标本时，估计标准误分别为2．9岁～5．4岁。各方程测试于广东法医尸体解剖案例的结果表明，用单颗牙齿推断年龄的估计标准误为3．7岁；测试于广西壮族人案例的结果表明，用单颗牙齿推断年龄的估计标准误为2．6岁。用同一个体多颗牙齿推断年龄的研究结果表明，根据不同的年龄分组范围，利用同一个体2颗牙齿推断年龄的估计标准误分别为0．8岁～2．6岁；同一个体3颗～4颗牙齿推断年龄的估计标准误分别为0．6岁～2．3岁。研究结果表明，如果检材条件许可，采用同一个体多颗牙齿推断个体年龄可明显提高推断年龄的准确性。     

Accuracy of developing tooth length as an estimate of age in human skeletal remains: the deciduous dentition

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 accuracy of 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 -0.14 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 +/-0.10 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. One seemingly 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.     

Age estimation using CT imaging of the third molar tooth, the medial clavicular epiphysis, and the spheno-occipital synchondrosis: a multifactorial approach

A multi-factorial method for estimating age was devised based on the development of the 3rd molar tooth, the medial clavicular epiphysis, and the spheno-occipital synchondrosis, using multiple regression as the means to construct age estimation formulae and CT scanning as the imaging modality. The sample consisted of approximately 600 individuals from a contemporary Australian population, between the ages of 15 and 25 years, who were admitted to the Victorian Institute of Forensic Medicine, Melbourne, Australia, for the purposes of medico-legal death investigation. Results show that the spheno-occipital synchondrosis does not contribute to the age estimation model for this age cohort. The regression computation for the 3rd molar tooth and medial clavicle, when combined into a single multiple regression calculation, provides a robust model with tighter age ranges at the 95% confidence interval (CI) than when each age marker is used individually. This research provides a method to estimate age for unknown age Australian individuals in the problematic age group of 15-25 years with greater precision than previously possible.     

合并自杀的杀人行为研究(附40例分析)

目的　探索合并自杀的杀人行为的犯罪学特征、发生机理 ,为责任能力的评定提供依据 ,并提出进一步研究方向。　方法　采用回顾性研究方法 ,3名研究人员从 1997年 1月～ 2 0 0 1年 10月的鉴定案例中挑出符合研究条件的案例 ,进行统计学分析 ,并结合国内外相关文献进行讨论。　结果　符合条件者共 40例 ,男性被鉴定人较多 (2 8名 ) ,平均年龄 33.5 5岁 ,主要年龄段 30～ 40岁 ,妄想和情绪低落等症状具有明显的作用 ,精神分裂症和无精神病在疾病诊断中占有显著地位。　结论　合并自杀的杀人行为具有一定的特征 ,应引起司法精神病学的关注 ,并展开更深入的研究。     

Co-offending and the diversification of crime types

There is theoretical and empirical support for co-offending being important not only for understanding current offending but also subsequent offending. The fundamental question is--why? In this article, an aggregate analysis is performed that begins to answer this question. Disaggregating solo- and co-offending by single year of age (12-29 years) and crime type in a largely metropolitan data set from British Columbia, Canada, 2002 to 2006, it is shown that the distribution of co-offences is significantly more varied than the distribution of solo offences. This more varied distribution of co-offences favors property crimes during youth but fades as offenders age.     

Facial soft tissue depths in craniofacial identification (part II): An analytical review of the published sub-adult data

Prior research indicates that while statistically significant differences exist between subcategories of the adult soft tissue depth data, magnitudes of difference are small and possess little practical meaning when measurement errors and variations between measurement methods are considered. These findings raise questions as to what variables may or may not hold meaning for the sub-adult data. Of primary interest is the effect of age, as these differences have the potential to surpass the magnitude of measurement error. Data from the five studies in the literature on sub-adults which describe values for single integer age groups were pooled and differences across the ages examined. From 1 to 18 years, most soft tissue depth measurements increased by less than 3 mm. These results suggest that dividing the data for children into more than two age groups is unlikely to hold many advantages. Data were therefore split into two groups with the division point corresponding to the mid-point of the observed trends and main data density (0-11 and 12-18 years; division point = 11.5 years). Published sub-adult data for seven further studies which reported broader age groups were pooled with the data above to produce the final tallied soft tissue depth tables. These tables hold the advantages of increased sample sizes (pogonion has greater than 1770 individuals for either age group) and increased levels of certainty (as random and opposing systematic errors specific to each independent study should average out when the data are combined).     

Preliminary report on a new method of human age estimation from single adult teeth.

A total of 317 upper and lower third molars were randomly divided into working and control samples and used to estimate chronological age employing a method which combined multiple regression analysis of data from Gustafson's and Maples's scoring system, direct morphological measurements obtained with a Kontron image analysis system and logarithmic data transformation. The standard errors of estimate were 2.4-6.8 years in the working sample and 1.9-7.5 years when the derived formulae were tested on the control sample, respectively. Compared to previous studies, this method provides a smaller standard error of estimate from a single molar tooth. The method is presently being tested on other tooth categories, like premolars, canines and other types of molars.     

Estimation of age from epiphyseal union at the wrist and ankle joints in the capital city of India

Various studies conducted in and outside India for estimation of age from long bone joints revealed that unlike other vital parameters no uniform pattern exists for epiphyseal union of long bones in different countries of the world and also in different parts of the same country. A radiological study was conducted in 180 boys and girls of the capital city of India, Delhi, between the age group of 14-20 years to find out the age at which epiphyseal union at wrist and ankle joint takes place. The result of the study showed that the wrist joint epiphyseal union is completed in all cases in the age group of 19-20 years in males and 18-19 years in females. In the ankle joint, 17-18 years was the age group in males and 16-17 years the age group in females which showed complete epiphyseal union in all cases.     

Applicability of Greulich and Pyle skeletal age standards to Indian children

A total 375 Indian children of age 1 day to 19 years were studied (male 194 and female 181). For determining the bone age (skeletal age), wrist and hand radiographs were taken. The skeletal age was determined by blinded review of radiograph using Greulich and Pyle atlas (2nd edition, 1959). If we consider all age group (1-19 years), the Indian boys were retarded in skeletal age by 0.7 years and females by 0.33 years. Male and female children skeletally lag behind the American standard (GP Atlas) in all age groups except 12-13 years age group in which girls are accelerated by 0.22 years. Chronological age and skeletal age difference of more than 1 year is seen between age group 7 years and 12 years in males. Females after second year showed a retardation, which ranged from 0.2 to 0.8 years, up to the age of 19 years. The present study concludes that, Greulich and Pyle atlas is not applicable to the Indian children of both sexes especially in middle and late childhood.     

Age-at-death diagnosis and determination of life-history parameters by incremental lines in human dental cementum as an identification aid

Incremental lines in acellular extrinsic fiber cementum of 91 roots from 80 freshly extracted teeth have been investigated for a verification of the suitability of pathological teeth for a valid age-at-death diagnosis. Independent from tooth type, the accuracy of histological age-at-death diagnosis is clearly a function of a tooth's pathological state. Various periodontal diseases lead to a reduced number of incremental lines, while teeth with a sufficient nutritional support of their root showed a deviation of the histological age from the known actual age of 2-3 years only. For all patients, a detailed query concerning a variety of life-history parameters was established. We are able to show that especially previous pregnancies, skeletal traumata and renal diseases which all have a marked influence on the calcium metabolism result in hypomineralized incremental lines. The year of production of these hypomineralized lines could be dated precisely. Differential quality of incremental lines can, therefore, serve as a valuable tool in identification cases.     

Vitreous humor carbohydrate-deficient transferrin concentrations in the postmortem diagnosis of alcoholism

Deaths from the effects of alcohol intoxication are encountered routinely in forensic practice. In an important number of cases difficulty may arise in interpreting the significance of results obtained in the autopsy. In clinical practice biochemical markers, particularly serum gamma-glutamyl-transpeptidase (GGT), alanine aminotransferase (ALT), aspartate transaminase (AST), carbohydrate-deficient transferrin (CDT), and erythrocyte mean corpuscular volume are used to diagnose heavy alcohol consumption. CDT is used as a reliable and specific marker. In postmortem diagnosis, because of the difficulty in interpreting blood alcohol levels and relatively non-specific pathological features, biochemical compounds have been studied for use as possible markers. The aim of this study was to evaluate the usefulness of the postmortem determination of CDT in vitreous humor as a confirmation of antemortem alcoholism. CDT levels were studied in 66 male cadavers with a mean age of 55.9 years (S.D. 17.0, range 22-87 years) with a mean postmortem interval of 17.9 h (S.D. 11.4, range 4-72 h). Cases were assigned to two diagnostic groups according to the antemortem diagnosis of alcoholism. Statistically significant differences were found for CDT and ALT concentrations between the two diagnostic groups. The highest vitreous humor levels of CDT and ALT were obtained in the group of cases with a previous diagnosis of alcoholism. Our results suggest that vitreous humor CDT levels are useful in cases where the postmortem diagnosis of alcoholism is hindered by the non-specificity of data.     

Age-at-death estimation based on the study of frontosphenoidal sutures

Determination of age at the time of death based on the observation of cranial sutures has led to numerous studies with sometimes contradictory results. The initial hypothesis being that suture closure is part of an age-related physiological process, the conflicting results have been interpreted by various authors as secondary to the choice of sutures, under the co-existing influence of pathological factors or genetic factors, or even independent of age. Despite these differences, macroscopic methods remain much used in anthropology and in forensic medicine. In our work, we evaluated the value of the degree of closure of the frontosphenoidal suture in estimating age at death of mature subjects, with the secondary objective of establishing a linear regression which could be used in routine practice. The study concerned bone specimens from individuals whose age, sex and medical history were known. Macroscopic observation was carried out on the ectocranial and endocranial sides according to four stages of closure previously defined. 290 sutures were taken from a population of whom two-thirds were men. The method can be repeated and reproduced and the regression established shows the confidence range for average error to be +/-1.5 years. While this result is of interest in terms of precision in prediction for a group of people, the prediction range is too great (+/-23 years) to be applicable to a single individual as part of a forensic procedure.     

Evaluation of age estimation technique: testing traits of the acetabulum to estimate age at death in adult males

This study evaluates the accuracy and precision of a skeletal age estimation method, using the acetabulum of 100 male ossa coxae from the Grant Collection (GRO) at the University of Toronto, Canada. Age at death was obtained using Bayesian inference and a computational application (IDADE2) that requires a reference population, close in geographic and temporal distribution to the target case, to calibrate age ranges from scores generated by the technique. The inaccuracy of this method is 8 years. The direction of bias indicates the acetabulum technique tends to underestimate age. The categories 46-65 and 76-90 years exhibit the smallest inaccuracy (0.2), suggesting that this method may be appropriate for individuals over 40 years. Eighty-three percent of age estimates were ±12 years of known age; 79% were ±10 years of known age; and 62% were ±5 years of known age. Identifying a suitable reference population is the most significant limitation of this technique for forensic applications.     

Age estimation by measurements of developing teeth: accuracy of Cameriere's method on a Brazilian sample

Developing teeth are commonly the criteria used for age estimation in children and young adults. The method developed by Cameriere et al. (Int J Legal Med 2006;120:49-52) is based on measures of teeth with open apex, and application of a formula, to estimate chronological age of children. The present study evaluated a sample of panoramic radiographs from Brazilian children from 5 to 15 years of age, to evaluate the accuracy of the method proposed by Cameriere et al. The results has proven the system reliable for age estimation, with a median residual error of -0.014 years between chronological and estimated ages (p = 0.603). There was a slight tendency to overestimate the ages of 5-10 years and underestimate the ages of 11-15 years.     

青少年手腕骨骨龄与生活年龄的差异观察

目的比较以不同骨龄标准所评价的青少年手腕骨骨龄与生活年龄的差异,观察生长发育长期变化对青少年年龄推测的影响。方法从中国5座大中城市抽取11464名（男5873,女5591）3～18岁汉族正常青少年儿童,并另随机抽取950名（男516,女434）12～18岁骨发育正常的汉族青少年作为验证样本。按CHN法和RC法骨龄标准评价手腕部X线片骨龄,并对不同方法评价的骨龄及生活年龄进行统计学分析。结果各年龄组CHN法骨龄中位数大于RC骨龄,其差异具有显著性意义（P〈0．05）。验证样本中,在男12—16．5岁、女12～14．5岁之间,CHN骨龄减生活年龄之差值分别为0．35—1．00岁和0．57～1．16岁（P〈0．01）;RC骨龄减生活年龄的差值分别为-0．26—0．23岁和-0．27～0．06岁（P〉0．05）。在男17～18岁、女15～17岁之间,CHN骨龄减生活年龄的差值分别为-0．52～-1．05岁和-0．16～-1．13岁（P〈0．05）,RC骨龄减生活年龄的差值分别为-0．35～-0．48岁和-0．22～-0．79岁（P〈0．05）。结论CHN法骨龄高于生活年龄,在大部分年龄组RC骨龄与生活年龄基本一致。     

Evaluation of post-mortem estimated dental age versus real age: a retrospective 21-year survey

The aim of the study was to evaluate the reliability of methods used for forensic dental age estimation. We analysed all cases over the last 21 years (1984-2004) of unidentified bodies that were examined for identification purposes (including age assessment), and of which secure identification was subsequently achieved. In total, the study included 51 cases and 7 different methods had been used for dental age estimation, with the Bang/Ramm and the Gustafson/Johanson methods being the most frequently applied. The age estimates had usually been recorded as 10-year intervals. Factual ages at death were in the range of 6-76 years, with the largest concentration of cases being in the age interval of 25-55 years (34 cases). There was good agreement between estimated age interval and factual age at death in 37/51 (72%) of the cases. In eight cases the factual age at death deviated up to +/-5 years from the estimated age, and in six cases by more than 6 years. The average difference between factual age at death and estimated age was 4.5 years. The four subadults in the material were all correctly estimated within an age range of +/-3 years. Our study showed that forensic odontological age estimates are reliable. However, the implementation of the specific methods may need to be adjusted concerning age ranges. In the future we recommend to register anamnestic information and the different steps in the methods used. Clinical evaluation should contain more details about attrition, colour, number and presumed age of the restorations and periodontal status.     

Comparison of four skeletal methods for the estimation of age at death on white and black adults

ABSTRACT: When analyzing human adult skeletal remains, it is often difficult to decide whether a single aging method will give a more reliable age estimation than a combination of methods. This study evaluates four macroscopic indicators for age estimation on 218 American White and Black individuals, ranging in age from 25 to 90 years of age, from the Terry collection. Individuals in the sample were selected to have a balanced race, sex, and age distribution. The following aging methods were applied to each skeleton by one experienced observer: the Suchey–Brooks (SB) pubic symphysis method, the Lovejoy auricular surface method, the monoradicular teeth Lamendin (LM) method, and the I?can (IC) method for fourth ribs. The statistical study involved the evaluation of inaccuracy and bias (based on median age) for each age indicator and the combination of methods using Principal component analysis (PCA). Analysis was performed on the entire sample, then by race, then sex, and then age group (25–40 years, 41–60 years, and >60 years). PCA was the most accurate method for both racial groups when all age groups are analyzed together. When the sample was divided into age groups, SB was the most accurate for young adults (25–40 years) and LM was the most accurate for middle adults (41–60 years). After the age of 60, all methods are highly inaccurate, although IC gives the lowest inaccuracy. As regards bias, the study highlights the tendency of all methods to overestimate the age of young individuals and to underestimate in the older age group. No single skeletal indicator of age at death is ever likely to reflect accurately the many factors that accumulate with chronological age. In fact, one must use as many dental and skeletal indicators as possible. However, in order to maximize the potential of each method, in the final evaluation one should consider mainly the method or methods that have a higher accuracy for a particular age range.     

The accuracy of three methods of age estimation using radiographic measurements of developing teeth

The accuracy of age estimation using three quantitative methods of developing permanent teeth was investigated. These were M?rnstad et al. [Scand. J. Dent. Res. 102 (1994) 137], Liversidge and Molleson [J. For. Sci. 44 (1999) 917] and Carels et al. [J. Biol. Bucc. 19 (1991) 297]. The sample consisted of 145 white Caucasian children (75 girls, 70 boys) aged between 8 and 13 years. Tooth length and apex width of mandibular canine, premolars and first and second molars were measured from orthopantomographs using a digitiser. These data were substituted into equations from the three methods and estimated age was calculated and compared to chronological age. Age was under-estimated in boys and girls using all the three methods; the mean difference between chronological and estimated ages for method I was -0.83 (standard deviation +/-0.96) years for boys and -0.67 (+/-0.76) years for girls; method II -0.79 (+/-0.93) and -0.63 (+/-0.92); method III -1.03 (+/-1.48) and -1.35 (+/-1.11) for boys and girls, respectively. Further analysis of age cohorts, found the most accurate method to be method I for the age group 8.00-8.99 years where age could be predicted to 0.14+/-0.44 years (boys) and 0.10+/-0.32 years (girls). Accuracy was greater for younger children compared to older children and this decreased with age.