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1.
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.  相似文献   

2.
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   

3.
Age estimation by IBAS image analysis of teeth   总被引:2,自引:0,他引:2  
The study of teeth to estimate age in a cadaver or in remains has become widely accepted in legal medicine, especially since the appearance of Gustafson's work in 1950. However, many studies published since that time have questioned the accuracy of these determinations. Computerized image analysis (IBAS) provides much more precise measurements of the parameters involved in these studies. An IBAS I (Kontron) image analysis system was used to study 19 different morphological parameters in midsagittal sections of a total of 173 upper and lower central incisors from as many live subjects. The data thus obtained provide useful information for determining the subject's age.  相似文献   

4.
5.
Current standards for age at death estimation from the pelvis are based on Americans of European and African ancestry. Our limited understanding of population variability hampers our efforts to apply these techniques to the various skeletal populations around the world, especially in global forensic contexts. However, documented skeletal samples are rare, limiting our ability to test our techniques. This study tested the Suchey-Brooks pubic symphysis aging method and the auricular surface method originally developed by Lovejoy et al. on a large sample (n = 404) of known sex and age from the Sassari Collection, housed at the Museum of Anthropology at the University of Bologna, Italy. The results indicate that for both methods, bias and inaccuracy increased with age and actual age tended to be underestimated over the age of 40. The auricular surface method performed slightly better, exhibiting slightly lower levels of bias and inaccuracy, especially for males.  相似文献   

6.
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.  相似文献   

7.
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   

8.
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   

9.
Age estimation from the rib by phase analysis: white females   总被引:4,自引:0,他引:4  
Metamorphosis at the sternal extremity of the rib has already been established as a reliable indicator of age at death. Using a sample of white males, it was shown that an accurate estimation of age can be made by direct examination of the bone itself. However, because of sexual differences in hormonal production and dimorphism in the skeleton, the present study was carried out to develop an appropriate standard for age determination from the sternal rib in white females. The sample consisted of 86 ribs of known age, sex, and race. Observations were made at the costochondral junction with special attention to pit formation (its shape and depth), changes in the walls and rim surrounding it, and overall bone density and texture. Based on changes in these areas, the ribs were separated into nine phases (0 through 8). The most rapid metamorphosis occurred in Phases 1 through 4 (mean ages 14-28) with changes noticeable at 3 to 4 year intervals. After mean age 28, this process slowed, considerably expanding the interval between phases to 10 to 15 years. The female ribs showed both earlier initial pit formation and a different morphologic pattern of aging as compared with males. Statistical analysis revealed that the features chosen to delineate the phases are valid predictors of age. This study has shown that the sternal rib can provide an accurate estimation of age in females spanning a mean age of 14 to 76 years.  相似文献   

10.
Previous studies have shown that with advancing age the size of the dental pulp cavity is reduced as a result of secondary dentine deposit, so that measurements of this reduction can be used as an indicator of age. The aim of the present study was to find a method which could be used to estimate the chronological age of an adult from measurements of the size of the pulp on full mouth dental radiographs. The material consisted of periapical radiographs from 100 dental patients who had attended the clinics of the Dental Faculty in Oslo. The radiographs of six types of teeth from each jaw were measured: maxillary central and lateral incisors and second premolars, and mandibular lateral incisors, canines and first premolars. To compensate for differences in magnification and angulation on the radiographs, the following ratios were calculated: pulp/root length, pulp/tooth length, tooth/root length and pulp/root width at three different levels. Statistical analyses showed that Pearson's correlation coefficient between age and the different ratios for each type of tooth was significant, except for the ratio between tooth and root length, which was, therefore, excluded from further analysis. Principal component analyses were performed on all ratios, followed by regression analyses with age as dependent variable and the principal components as independent variables. The principal component analyses showed that only the two first of them had significant influence on age, and a good and easily calculated approximation to the first component was found to be the mean of all the ratios. A good approximation to the second principal component was found to be the difference between the mean of two width ratios and the mean of two length ratios, and these approximations of the first and second principal components were chosen as predictors in regression analyses with age as the dependent variable. The coefficient of determination (r2) for the estimation was strongest when the ratios of the six teeth were included (r2 = 0.76) and weakest when measurements from the mandibular canines alone were included (r2 = 0.56). Measurement on dental radiographs may be a non-invasive technique for estimating the age of adults, both living and dead, in forensic work and in archaeological studies, but the method ought to be tested on an independent sample.  相似文献   

11.
Methods of estimating adult age at death from such dental features as root translucency, root length, and the extent of periodontosis in intact single rooted teeth have proven useful in studies of modern individuals, especially in estimating age in older adults. Questions remain however, concerning the impact of regional and population variation on accuracy. To examine this issue, three approaches to age estimation were applied to a diverse sample of 100 individuals from Peru. Mean errors of estimation for all three approaches were similar to those originally reported, suggesting minimal impact of population variation of the features measured. A new regression equation, specifically for Peruvian samples, is provided.  相似文献   

12.
Age estimation using the racemization of amino acid in human dentin   总被引:2,自引:0,他引:2  
This study was made to improve the validity of age estimation from teeth using amino acid racemization. The correlation between actual age and the D/L ratio of aspartic acid was investigated by analyzing not only the total amino acid but also its fractionated substances, insoluble collagen and soluble peptide. The coefficient values of correlation between the D/L ratio and actual age in adult lower central incisors were 0.996 (sigma = +/- 1.0 year) for the total amino acid, 0.988 (sigma = +/- 1.8 years) for insoluble collagen, and 0.997 (sigma = +/- 0.9 years) for soluble peptide. The corresponding figures in adult first premolars were 0.991 (sigma = +/- 1.6 years), 0.988 (sigma = +/- 1.9 years), and 0.994 (sigma = +/- 1.4 years), respectively. The reactive velocity of aspartic acid racemization was highest for soluble peptide in both the lower central incisors and first premolars and approximately three times as rapid as that for total amino acid. As a result, age estimated from the analysis of soluble peptide was most accurate. The velocity for insoluble collagen was slightly lower than that for total amino acid. Age estimation was attempted from the teeth of an unknown body. These results suggest that the analyses, not only of total amino acid in dentin but also of its fractionated and extracted substances, can lead to higher reliability in age estimation. Soluble peptide, in particular, has been found to be most effective.  相似文献   

13.
14.
As an antihistamine, diphenhydramine (DPH) is well known for its use in allergy treatment. Since its introduction in 1946, it has been marketed under various trade names, the most popular being Benadryl. Three years after its introduction, the first fatality due to DPH toxicity was reported in 1949.To better understand the incidence of fatalities due to DPH monointoxication, we reviewed deaths that were reported from 2 data sources: (1) the English-language literature using PubMed, from 1946 through 2003; and (2) the Annual Report of the American Association of Poison Control Centers Toxic Exposure Surveillance System (ARAAPCCTESS), from 1983 through 2002. The results were then tabulated using age, gender, clinicopathologic findings, and toxicology results.Combined results from both data sets show the following mean (and range) for age and DPH levels: Adult, 35.6 years (18-84) and 19.53 mg/L (0.087-48.5); pediatric, 8.6 years (1.25-17) and 7.4 mg/L (1.3-13.7); infant, 31 weeks (6 weeks-11 months) and 1.53 mg/L (1.1-2.2), respectively.Most deaths were certified as accident or suicide; however, 6 infant homicides were reported. The most common symptoms for all cases were cardiac dysrhythmias, seizure activity, and/or sympathetic pupil responses. The most common autopsy finding was pulmonary congestion.  相似文献   

15.
Modifications to the Gustafson method of age estimation from teeth are described. They are designed to minimise the subjective nature of the scoring technique and to quantify the regressive changes in the enamel, dentine and cementum. Randomly selected teeth from 25 Indians were examined by the Gustafson method and by our own modification. It was shown that our modified method resulted in more accurate and reproducible age estimations than did the original method.  相似文献   

16.
中国人男性硬腭的年龄变化研究   总被引:2,自引:0,他引:2  
目的探讨腭缝及硬腭骨质年龄变化的规律,建立腭骨年龄判定的方法。方法对268例已知生前确切年龄的中国汉族男性的上腭硬腭腭缝的愈合情况及硬腭表面的骨质情况,进行了观察,将观察结果进行评分分级后,探讨硬腭骨骼特征与年龄的关系。结果将硬腭骨骼特征与年龄进行相关分析,并建立硬腭判定年龄的多组回归方程,判断年龄误差最小的为4.5岁。结论本文提出的硬腭年龄判定的方法,准确性较高,在较大年龄组的个体也可以得到较好的结果,是骨骼年龄判定的一个新的实用、可靠的方法。  相似文献   

17.
There are several approaches to the organization of an activity. Some of the better known methods are by function, project or a matrix. Each of these methods is investigated in terms of its effect on innovation. Some of the advantages and disadvantages of each are discussed. All discussion is carefully supported by reference to current literature.  相似文献   

18.
In recent years many countries have experienced a sharp increase in the demand for forensic age estimates of unaccompanied minors. In many countries the age thresholds of relevance to criminal prosecution lie between 16 and 22 years. In line with recommendations issued by the Study Group on Forensic Age Diagnostics, for determining the age of live subjects a forensic age estimate should combine the results of a physical examination, an X-ray of the hand and a dental examination which records dentition status and evaluates an orthopantomogram. To assess the age of persons who are assumed to be at least 18 years old, an additional radiographic or CT examination of the collar bones is recommended. Forensic age estimates should take account of the ethnic origin and socio-economic status of the person under examination.  相似文献   

19.
Recent years have brought a worldwide increase in cross-border migration due to a globalized economy and ongoing belligerent conflicts. As a result, the percentage of foreigners among the general population has steadily increased not only in Germany, but also in other countries. This trend has triggered a growing demand for forensic medicine to assess the age of adolescents and young adults. The individuals examined here are unaccompanied minors without valid identification documents who do not know their age or else are suspected of not giving their correct age. The mineralization of third molars is the main criterion for dental age estimation of living subjects in the relevant age group. To date insufficient knowledge has been obtained about how ethnic origin can influence tooth mineralization. This, however, constitutes a restraint on the reliability of age estimates and hence on the forensic value of information essential to legal security. A comparative study was conducted to present comparative data on third molar mineralization in a Caucasoid, Mongoloid and African sample. In conclusion, forensic age estimates of living subjects would be more powerful tools if population-specific standards were applied to evaluations of wisdom tooth mineralization. Since the mineralization of third molars is usually completed by the age of 19 or 20 years, this feature cannot be used to ascertain whether a person has attained the forensically relevant age of 21 years. The question was whether determination based on an orthopantomogram of a combination of features relevant to dental age estimation of adults supplies forensically useful information for ascertaining whether a person has attained 21 years of age. The features considered include the DMFT index of all permanent teeth, the DMFT index of all permanent teeth excluding third molars and the DFT index of third molars projecting beyond the occlusal plane. It can be concluded that an evaluation of the variations of the DMFT index does not by itself yield sufficient data to determine with the accuracy required in criminal proceedings whether a person has attained 21 years of age. An additional X-ray examination of the medial clavicular epiphyseal cartilage is, therefore, strongly recommended when assessing whether a person is over 21.  相似文献   

20.
Autoerotic death by hanging or ligature is a method of autoeroticism well known by forensic pathologists. In order to analyze autoerotic deaths of nonclassic hanging or ligature type, this paper reviews all published cases of autoerotic deaths from 1954 to 2004, with the exclusion of homicide cases or cases in which the autoerotic activity was not solitary. These articles were obtained through a systematic Medline database search. A total of 408 cases of such deaths has been reported in 57 articles. For each case, the following characteristics are presented here: sex, age, race, method of autoerotic activity, cause of death, and location where the body was found. Autoerotic death practioners were predominantly Caucasian males. Victims were aged from 9 to 77 years and were mainly found in various indoor locations. Most cases were asphyxia by hanging, ligature, plastic bags, chemical substances, or a mixture of these. Still, atypical methods of autoerotic activity leading to death accounted for about 10.3% of cases in the literature and are classified here into five broad categories: electrocution (3.7%), overdressing/body wrapping (1.5%), foreign body insertion (1.2%), atypical asphyxia method (2.9%), and miscellaneous (1.0%). All these atypical methods are further discussed individually.  相似文献   

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