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1.
The eruption of teeth in the mouth is suitable for age estimations during the period when teeth are actively emerging, in the deciduous dentition phase approximately from the age of 6 months to 2.5 years. Estimations of age can be performed simply by counting the number of teeth in the mouth. Reliability of the estimates depends on the reference data available and each population group should preferably have its own standards. In the present study timing of eruption of successive deciduous teeth was studied longitudinally in 129 Finns. The dates of clinical eruption of deciduous teeth were recorded by mothers and checked by dentists. In 40 of the 129 children emergence ages of at the most the four last teeth were based only on semiannual registrations performed by dentists. The main purpose was to provide normal timetables of tooth eruption in small children in forms that are practical in estimations of dental age. No sexual dimorphism existed in the timing of clinical eruption of successive deciduous teeth. The mean age corresponding to the presence of one tooth in the mouth was 7.1 months (S.D.=1.78) and that corresponding to tooth count 19 was 27.8 months (S.D.=3.99). If the chronological age is known, the presented distributions and means with variations make it possible to estimate the degree of advancement or delay in a child’s dental development. If the age of the child is not known, the mean and median ages can be used for estimations of chronological age. However, estimations of age should not be based only on tooth counts because of marked variation also within this homogeneous group.  相似文献   

2.
The aim of this study was to evaluate the applicability of Cameriere’s European formula for age estimation in children in South China and to adapt the formula to establish a more suitable formula for these children. Moreover, the performance of dental age estimation based on Cameriere’s method combining the developmental information of permanent teeth (PT) and third molar (TM) was also analysed. Orthopantomographs of 720 healthy children in Group A, and orthopantomographs of 320 children and 280 subadults in Group B were assessed. The samples of Group A were divided into training dataset 1 and test dataset 1, and the samples of Group B were also divided into training dataset 2 and test dataset 2. A South China-specific formula was established based on the training dataset 1, and the comparison of accuracy between the Cameriere’s European formula and the South China-specific formula was conducted with the test dataset 1. Additionally, a PT regression model, a TM regression model, and a combined regression model (PT + TM) were established based on the training dataset 2, and the performance of these three models were validated on the test dataset 2. The Cameriere’s European formula underestimated chronological age with a mean difference (ME) of −0.47 ± 1.11 years in males and −0.69 ± 1.19 years in females. However, the South China-specific formula underestimated chronological age, with a mean difference (ME) of −0.02 ± 0.71 years in males and −0.14 ± 0.73 years in females. Compared with PT model and TM model, the PT and TM combined model obtained the smallest root mean square error (RMSE) of 1.29 years in males and 0.93 years in females. In conclusion, the South China-specific formula was more suitable for assessing the dental age of children in South China, and the PT and TM combined model can improve the accuracy of dental age estimation in children.

Key points

  • Orthopantomographs of 720 healthy children in Group A, and orthopantomographs of 320 children and 280 subadults in Group B were assessed.
  • A South China-specific formula was established based on the training dataset 1, and the comparison of accuracy between the Cameriere’s European formula and the South China-specific formula was conducted with the test dataset 1.
  • A PT regression model, a TM regression model, and a combined regression model (PT + TM) were established based on the training dataset 2, and the performance of these three models were validated on the test dataset 2.
  • The South China-specific formula was more suitable for assessing the dental age of children in South China, and the PT and TM combined model can improve the accuracy of dental age estimation in children.
  相似文献   

3.
Bones and teeth often represent the only sources of DNA available for identifying human remains. DNA in bones and teeth is generally better preserved than that in soft tissues because of the presence of hard connective tissue with a high level of calcium. Because of the extensive mineralisation, the choice of an efficient DNA extraction procedure is important to minimise the sampling of a high level of minerals and to remove polymerase chain reaction (PCR) inhibitors. Some protocols are available for DNA extraction from bones and teeth as part of the Qiagen EZ1 DNA Investigator Kit using the EZ1 Advanced XL automated purification platform. To improve the efficiency of DNA extraction from skeletal remains, the present study focuses on a modification to these already available protocols. In this study, different bones and teeth collected between 1 and 50 years after death were subjected to DNA extraction using the standard EZ1 protocol, a supplementary protocol, and a modified protocol. The modified approach included a decalcification step, whereas the Qiagen protocols worked directly on non-decalcified powder. In all three procedures, 150 mg samples were used for DNA extraction. We evaluated the quantity of DNA recovered from samples, the presence of any PCR inhibitors co-extracted, the level of DNA degradation, the quality of short tandem repeat (STR) profiles, and the reproducibility of the modified procedure. When compared with the other protocols, the modified protocol resulted in the best recovery of DNA that was free of PCR inhibitors. Additionally, the STR profiles were reliable and of high quality. In our opinion, the decalcification step increases DNA recovery by softening tissues, which allows lysis solutions to act more effectively. Furthermore, the use of two lysis solutions and the variation added to the EZ1 purification step allow for DNA recovery with quality and quantity superior to those of the previously available Qiagen-based protocols. These findings may be helpful solutions to the problems commonly encountered when dealing with difficult samples, such as bones and teeth.

Key points

  • Bones and teeth often represent the only sources of DNA for identifying human remains.
  • The choice of an efficient DNA extraction procedure is important for maximizing DNA recovery and removing PCR inhibitors.
  • This study focuses on modifications to the previously available Qiagen-based protocols.
  • The modified protocol enabled the best recovery of DNA, and both quality and quantity were superior to those of the previously available Qiagen-based protocols.
  • The STR profiles obtained from samples extracted using the modified protocol were reliable and of high quality.
  相似文献   

4.
The expression of uncertainty is defined by the standard deviation and is usually expressed in multiples of the standard deviation (±1sd, ±2sd, and ±3sd). The objective was to use weighting of the sd calculation by the number or count of subjects for each tooth development stage. A comparison shows the difference between the range of uncertainty using the unweighted sd and the weighted sd. The range of uncertainty related to Dental Age Estimation is statistically significantly greater (p < 0.001) for the weighted sd compared to the unweighted sd. It is concluded that the number of subjects for each Tooth Development Stage in the Reference Data set should be included in the calculation for a single Dental Age Estimation using the Simple Average Method when presenting the uncertainty associated with the point estimate of the “mean” for Dental Age Estimation of a single subject of unknown age.  相似文献   

5.
The aim of the present study was to evaluate the validity of the modified Kim's scoring system as a practical method of recording occlusal tooth wear and estimating age. For this purpose, 1092 pairs of maxillary and mandibular full-arch casts were randomly selected, scored, and analyzed. The results showed that the modified Kim's scoring system had excellent reliability, and that occlusal tooth wear had a positive correlation with age. Tooth wear scores of all teeth except the two lower central incisors were higher in males than in females. Calculating tables for age estimation were designed by multiple linear regression analysis. Estimated ages were within +/-5 years of actual ages in 63.5% of male subjects, and 64.0% of female subjects. The accuracy of age estimation was increased when the subjects were divided into two age groups and data were re-analyzed. Collectively, it was shown that the modified Kim's scoring system is a reliable and accurate method for age estimation, and that the data from these 1092 individuals can be used as a standard for age estimation of Korean adults.  相似文献   

6.
The eruption times of permanent teeth and the sequence of tooth eruption were investigated in 952 individuals aged 4 to 24 years. Wisdom teeth were excluded from the evaluation. All individuals were inhabitants of Tehran, Iran. The results were compared to results of international studies on tooth eruption of the 20th century and studies published in recent years. The teeth emerged symmetrically in each jaw. However, teeth erupted earlier in the mandible than in the maxilla, excluding the earlier eruption of maxillary premolars. The sequence of emerging teeth in the maxilla is: first molar, central incisor, lateral incisor, first premolar, second premolar, canine, and second molar. The sequence of tooth eruption of the mandible differs from the maxillary sequence: first molar, central incisor, lateral incisor, canine, first premolar, second premolar, second molar. The sequence of all teeth is: lower first molar, lower central incisor, upper first molar, upper central incisor, lower lateral incisor, upper lateral incisor, upper first premolar, lower canine, lower first premolar, upper second premolar, upper canine, lower second premolar, lower second molar, and upper second molar. The results support current theories that the differences in tooth eruption times between humans of different ethnic origin are small.  相似文献   

7.
Sweden has witnessed an increase in the rates of sexual crimes including rape. Knowledge of who the offenders of these crimes are is therefore of importance for prevention. We aimed to study characteristics of individuals convicted of rape, aggravated rape, attempted rape or attempted aggravated rape (abbreviated rape+), against a woman ≥18 years of age, in Sweden. By using information from the Swedish Crime Register, offenders between 15 and 60 years old convicted of rape+ between 2000 and 2015 were included. Information on substance use disorders, previous criminality and psychiatric disorders were retrieved from Swedish population-based registers, and Latent Class Analysis (LCA) was used to identify classes of rape+ offenders. A total of 3 039 offenders were included in the analysis. A majority of them were immigrants (n = 1 800; 59.2%) of which a majority (n = 1 451; 47.7%) were born outside of Sweden. The LCA identified two classes: Class A — low offending class (LOC), and Class B — high offending class (HOC). While offenders in the LOC had low rates of previous criminality, psychiatric disorders and substance use disorders, those included in the HOC had high rates of previous criminality, psychiatric disorders and substance use disorders. While HOC may be composed by more “traditional” criminals probably known by the police, the LOC may represent individuals not previously known by the police. These two separated classes, as well as our finding in regard to a majority of the offenders being immigrants, warrants further studies that take into account the contextual characteristics among these offenders.

Key points

  • Rape, aggravated rape, attempted rape or attempted aggravated rape (rape+) are increasing in Sweden.
  • The majority of those convicted of rape+ are immigrants.
  • LCA identifies two classes of rape+ offenders: LOC and HOC.
  相似文献   

8.
Isotopic signatures used in the georeferencing of human remains are largely fixed by spatially distinct geologic and environmental processes. However, location-dependent temporal changes in these isotope ratios should also be considered when determining an individual’s provenance and/or trajectory. Distributions of the relevant isotopes can be impacted by predictable external factors such as climate change, delocalisation of food and water sources and changes in sources and uses of metals. Using Multi-Collector Inductively-Coupled Plasma Mass Spectrometer (MC-ICP-MS) analyses of 206Pb/207Pb in tooth enamel and dentin from a population of 21 ± 1-year-old individuals born circa 1984 and isotope ratio mass spectrometry (IRMS) of δ18O in their enamel, we examined the expected influence of some of these factors. The resulting adjustments to the geographic distribution of isotope ratios (isoscapes) found in tooth enamel and dentin may contain additional useful information for forensic identification, but the shifts in values can also impact the uncertainty and usefulness of identifications if they are not taken into account.

KEY POINTS

  • Isoscapes of 206Pb/207Pb and δ18O used for geolocation are not static.
  • Within a few years, the enamel and dentin of a person may exhibit measurable differences in 206Pb/207Pb even without changing locations.
  • Changes in climatic patterns tied to rising temperatures are more significant than the direct effect of increasing temperature on δ18O fixed in tooth bioapatite.
  • Third molar (M3) enamel mineralisation includes material incorporated from before formal amelogenesis takes place.
  相似文献   

9.
The aim of this study was to determine the eruption times of permanent teeth, excluding third molars, in a defined area population of a country district in Lower Saxony. The authors investigated 2495 oral findings of 664 patients (male 315, female 349) in a longitudinal study. The minimum age was 3.00 years and the maximum age 24.00 years. The dental findings were collected over a period of about 20 years (1980-2002). The oral findings per child/adolescent were assessed between one and 16 times. The eruption times of teeth in females are earlier than those for the same teeth in males. Further, the permanent dentition in females is completed earlier than in males. The tooth eruption occurs symmetrically in both jaws. The comparison of both jaws revealed a slightly advanced eruption of the lower jaw teeth for both sexes. There is a noteworthy change in the eruption sequence of the teeth. In contrast to other reports we determined that the eruption of the canine proceeds the eruption of the second premolar. We found no acceleration of the dentition when compared to other reports and confirmed the rules of tooth eruption in man. Oral examination of teeth is a simple tool to calculate tooth eruption intervals. This first investigation on a population of Lower Saxony revealed a change in the eruption sequence of permanent teeth. The findings are relevant for dental treatment planning and should be reconfirmed at certain intervals.  相似文献   

10.
The eruption of teeth in the mouth is suitable for age estimations during the period when teeth are actively emerging, in the deciduous dentition phase approximately from the age of 6 months to 2.5 years. Estimations of age can be performed simply by counting the number of teeth in the mouth. Reliability of the estimates depends on the reference data available and each population group should preferably have its own standards. In the present study timing of eruption of successive deciduous teeth was studied longitudinally in 129 Finns. The dates of clinical eruption of deciduous teeth were recorded by mothers and checked by dentists. In 40 of the 129 children emergence ages of at the most the four last teeth were based only on semiannual registrations performed by dentists. The main purpose was to provide normal timetables of tooth eruption in small children in forms that are practical in estimations of dental age. No sexual dimorphism existed in the timing of clinical eruption of successive deciduous teeth. The mean age corresponding to the presence of one tooth in the mouth was 7.1 months (S.D.=1.78) and that corresponding to tooth count 19 was 27.8 months (S.D.=3.99). If the chronological age is known, the presented distributions and means with variations make it possible to estimate the degree of advancement or delay in a child's dental development. If the age of the child is not known, the mean and median ages can be used for estimations of chronological age. However, estimations of age should not be based only on tooth counts because of marked variation also within this homogeneous group.  相似文献   

11.
目的 通过三维重建测量上、下颌尖牙髓腔/牙体表面积比值(Pulp/Tooth area Ratio,PTR)来推断个体年龄,为临床年龄推断的应用提供科学依据.方法 收集口腔门诊患者年龄在16~65岁200例锥形束CT(Cone beam computed tomography,CBCT)影像资料,以4个尖牙为测量对象并...  相似文献   

12.
Developing teeth are used to assess maturity and estimate age in a number of disciplines, however the accuracy of different methods has not been systematically investigated. The aim of this study was to determine the accuracy of several methods. Tooth formation was assessed from radiographs of healthy children attending a dental teaching hospital. The sample was 946 children (491 boys, 455 girls, aged 3-16.99 years) with similar number of children from Bangladeshi and British Caucasian ethnic origin. Panoramic radiographs were examined and seven mandibular teeth staged according to Demirjian's dental maturity scale [A. Demirjian, Dental development, CD-ROM, Silver Platter Education, University of Montreal, Montreal, 1993-1994; A. Demirjian, H. Goldstein, J.M. Tanner, A new system of dental age assessment, Hum. Biol. 45 (1973) 211-227; A. Demirjian, H. Goldstein, New systems for dental maturity based on seven and four teeth, Ann. Hum. Biol. 3 (1976) 411-421], Nolla [C.M. Nolla, The development of the permanent teeth, J. Dent. Child. 27 (1960) 254-266] and Haavikko [K. Haavikko, The formation and the alveolar and clinical eruption of the permanent teeth. An orthopantomographic study. Proc. Finn. Dent. Soc. 66 (1970) 103-170]. Dental age was calculated for each method, including an adaptation of Demirjian's method with updated scoring [G. Willems, A. Van Olmen, B. Spiessens, C. Carels, Dental age estimation in Belgian children: Demirjian's technique revisited, J. Forensic Sci. 46 (2001) 893-895]. The mean difference (+/-S.D. in years) between dental and real age was calculated for each method and in the case of Haavikko, each tooth type; and tested using t-test. Mean difference was also calculated for the age group 3-13.99 years for Haavikko (mean and individual teeth). Results show that the most accurate method was by Willems [G. Willems, A. Van Olmen, B. Spiessens, C. Carels, Dental age estimation in Belgian children: Demirjian's technique revisited, J. Forensic Sci. 46 (2001) 893-895] (boys -0.05+/-0.81, girls -0.20+/-0.89, both -0.12 y+/-0.85), Demirjian [A. Demirjian, Dental development, CD-ROM, Silver Platter Education, University of Montreal, Montreal, 1993-1994] overestimated age (boys 0.25+/-0.84, girls 0.23+/-0.84, both 0.24 y+/-0.86), while Nolla [C.M. Nolla, The development of the permanent teeth, J. Dent. Child. 27 (1960) 254-266] and Haavikko's [K. Haavikko, The formation and the alveolar and clinical eruption of the permanent teeth. An orthopantomographic study, Proc. Finn. Dent. Soc. 66 (1970) 103-170] methods under-estimated age (boys -0.87+/-0.87, girls -1.18+/-0.96, both -1.02 y+/-0.93; boys -0.56+/-0.91, girls -0.79+/-1.11, both -0.67 y+/-1.01, respectively). For individual teeth using Haavikko's method, first premolar and second molar were most accurate; and more accurate than the mean value of all developing teeth. The 95% confidence interval of the mean was least for mean of all developing teeth using Haavikko (age 3-13.99 years), followed by identical values for Demirjian and Willems (sexes combined).  相似文献   

13.
A new method was developed for pre-concentration and determination of multiple drugs of abuse in human urine using dispersive liquid–liquid microextraction (DLLME) and capillary electrophoresis (CE) with photodiode array detection. The method was based on the formation of tiny droplets of an organic extractant in the prepared sample solution using water-immiscible organic solvent (chloroform) dissolved in water-miscible organic dispersive solvent (isopropyl alcohol). The organic phase, which extracted eight drugs of abuse from the prepared urine solution, was separated by centrifugation. The sedimented phase was transferred into a small volume CE auto-sampler vial with 10 µL of 1% HCl methanol solution and evaporated to dryness. The residue was reconstituted in lidocaine hydrochloride (internal standard) aqueous solution and introduced by electrokinetic injection into CE. Under the optimum conditions, acceptable linear relationship was observed in the range of 3.0–500 ng/mL with the correlation coefficient (r) of 0.9982–0.9994 for spiked urine samples. The limit of detection (LOD) (S/N = 3) was estimated to be 1.0 ng/mL. A recovery of 75.7%–90.6% was obtained for spiked samples. The mean relative error (MRE) was within ±7.0% and the relative standard deviation (RSD) was less than 6.9%. The proposed DLLME-CE procedure offers an alternative analytical approach for the sensitive detection of drugs of abuse in real urine samples.

Key points

  • The dispersive liquid-liquid microextraction (DLLME) was involved for the determination of drugs in urine with capillary electrophoresis with photodiode array detection (CE-PDA).
  • Good linearity, sensitivity, recovery and precision were achieved.
  • The proposed method was eco-friendly with microliter scale solvent consumption.
  相似文献   

14.
The aim of this cross-sectional study was to evaluate the dental formulas according to age because of possible changes during the last decades. From these dental formulas, the median age of emergence for the permanent teeth was deduced. The study population corresponded to the 1 to 15 year-old children who had consulted either a pediatric dentist or orthodontist in the city of Nice (France). Data were collected from the 5,848 patients' charts that included an orthopantomography. This permitted the observation of emerged teeth and agenesis. Bar charts were used to indicate the dental formula according to age. There was no significant difference in the emergence pattern of both controlateral maxillary and mandibular teeth. Only the anterior tooth emergence significantly differed according to the maxillary. The lower central incisor was the lone tooth with a median age earlier than others; the remaining teeth had an age equivalent to those of previously estimates.  相似文献   

15.
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.  相似文献   

16.
Massively parallel sequencing (MPS) offers a useful alternative to capillary electrophoresis (CE) based analysis of human identification markers in forensic genetics. By sequencing short tandem repeats (STRs) instead of determining the fragment lengths by CE, the sequence variation within the repeat region and the flanking regions may be identified. In this study, we typed 264 Uyghur individuals using the MiSeq FGx™ Forensic Genomics System and Primer Mix A of the ForenSeq™ DNA Signature Prep Kit that amplifies 27 autosomal STRs, 25 Y-STRs, seven X-STRs, and 94 HID-SNPs. STRinNGS v.1.0 and GATK 3.6 were used to analyse the STR regions and HID-SNPs, respectively. Increased allelic diversity was observed for 33 STRs with the PCR-MPS assay. The largest increases were found in DYS389II and D12S391, where the numbers of sequenced alleles were 3–4 times larger than those of alleles determined by repeat length alone. A relatively large number of flanking region variants (28 SNPs and three InDels) were observed in the Uyghur population. Seventeen of the flanking region SNPs were rare, and 12 of these SNPs had no accession number in dbSNP. The combined mean match probability and typical paternity index based on 26 sequenced autosomal STRs were 3.85E−36 and 1.49E + 16, respectively. This was 10 000 times lower and 1 000 times higher, respectively, than the same parameters calculated from STR repeat lengths.

Key Points

  • Sequencing data on STRs and SNPs used for human identification are presented for the Uyghur population.
  • STRinNGS v.1.0 was used to analyse the flanking regions of STRs.
  • The concordance between PCR-CE and PCR-MPS results was 99.86%.
  • Detection of sequence variation in STRs and their flanking regions increased the allelic diversity.
  相似文献   

17.
Organisations in both business and government face a considerable risk from inadequately secured information systems. In recognition of these risks, Directorate-General XIII (Telecommunications, Information Industries and Innovation) of the Commission of the European Communities commissioned a series of projects to examine security issues in the use of information technology. The results of one of these studies, concentrating on the security of network systems, is reviewed below.It was an objective of the study that its results should be seen as definitive, authoritative and applicable across the European Community as a whole. In order to meet this objective, the study, led by Coopers & Lybrand, drew upon the skills and experience of 44 organisations in seven European countries, including:
  • &#x02022;⊎ Coopers and Lybrand practices in France, Germany, Italy, the Netherlands and the United Kingdom;
  • &#x02022;⊎ Admiral Management Services Ltd;
  • &#x02022;⊎ The Commission of the European Communities;
  • &#x02022;⊎ 17 vendors of IT products and services in five European countries;
  • &#x02022;⊎ 20 major users of network systems in seven European countries.
In particular, the study benefited from detailed case studies in each of the 20 large and sophisticated users of network systems and from assessments of 27 security products from twelve IT vendors.  相似文献   

18.
The availability of more quantitative data on flunitrazepam (FLU) and 7-aminoflunitrazepam (7AF) would aid in obtaining a better understanding of the interpretation of FLU concentrations in human hair. The purpose of this study was to provide concentrations of FLU and 7AF in hair segments of 22 FLU users. Quantitative data regarding hair concentrations of FLU and 7AF from various types of cases were also reviewed to give a comprehensive overview of the comparability of different studies. Three to six 1 cm segments of scalp hair from 22 FLU users were analyzed by a liquid chromatography–tandem mass spectrometry (LC–MS/MS) method. FLU and its metabolite were confirmed in the hair segments from all cases. Concentrations of FLU and 7AF in the segments ranged from 0.01–0.16 ng/mg (median of 0.03) and 0.01–0.34 ng/mg (median of 0.09), respectively. Most cases had FLU and 7AF distributions along the hair segments that were suggestive of repeated drug use. A summary of the published concentrations gives valuable data and can assist forensic investigators in their estimations of drug use history and patterns.

Key points

  • A method using LC–MS/MS to quantify flunitrazepam and its metabolite was described.
  • Segmental analysis of flunitrazepam and its metabolite in human hair was reported.
  • A comprehensive overview of quantitative data was given.
  相似文献   

19.
In 1993, the skeletal remains of a female corpse were found in Burgenland, Austria. Initial identification of the approximately 25–35-year-old female appeared impossible, but the case was reopened 23 years later. By applying biogeochemical isotope methods to her body tissues, the geographical origin of the unknown corpse could be predicted. The results of the C, N, S, H, Sr, and Pb isotope analyses suggested that the female did not originate from Europe and most likely spent her youth in the northern Caribbean. Using these findings, the police were able to identify the woman within 2 weeks. The female came from the Dominican Republic and resided in Austria for only a short period before she was murdered. This case shows that isotope biogeochemistry investigations can provide the police with crucial information that enables unknown persons to be identified.

Keypoints

  • C-N-S-H and Sr-Pb isotope analyses were applied to human remains associated with a cold case.
  • It was possible to determine the region of origin of the unknown deceased individual as the northern Caribbean.
  • After 23 years, the murder victim was successfully identified.
  相似文献   

20.
Developing teeth are widely used to predict age in archaeology and forensic science. Regression equations of tooth length for age is a direct method, however, data for permanent teeth is incomplete. The aims of this study were: (a) to calculate regression equations predicting age from tooth length of all permanent teeth from birth to maturity, and (b) to evaluate the difference between radiographic and actual tooth length. The sample studied (N = 76, age range 0 to 19 years) was the Spitalfields juveniles of recorded age-at-death. Tooth length was measured from incisal tip to developing edge of crown or root of 354 dissected teeth. Data for upper and lower teeth were combined except for the lateral incisor. The least squares regression method was used to analyze the data for each tooth type; age being regressed against tooth length for prediction. For most tooth types, growth followed an S-shaped (polynomial) curve with initial fast growth and a further growth spurt around the time of mid root formation. No difference was found between radiographic and true tooth length. These regression equations provide an easy method of predicting age from any developing permanent tooth by measuring tooth length from isolated teeth or from unmagnified, undistorted radiographs.  相似文献   

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