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Utilization of forensic dentistry in indentification of individuals
Fialková, Martina ; Velemínská, Jana (advisor) ; Stránská, Petra (referee)
Forensic identification and age estimation has a significant role in cases when the unknown deceased body is found, after mass disasters when it is necessary to distinguish victims, but also in guestion of imigrants. And just these areas are very important part of forensic odontology, because dental development like a complex proces takes place from early foetal life to approximately 20 years of age is less affected by endocrine diseases or nutritional variations than other tissues. Dental age estimate is fundamental mainly in cases of children and young people, which teeth are still growing and they are in different developmental stages. On basis of these stages is possible to obtain very accurate results.
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Evaluation of ontogenetic development of the mandible using geometric morphometric methods
Kiebelová, Alena ; Velemínská, Jana (advisor) ; Brůžek, Jaroslav (referee)
During ontogeny there are a lot of changes in the entire human skeleton. This thesis deals with shape changes in the mandible, which are caused by genetic, hormonal, as well as mechanical factors. The most important mechanical factors influencing the shape of mandible are development of deciduous and permanent dentition and also development of masticatory muscles. 34 children mandibles of known age and 14 adult mandibles were analysed and compared for this thesis. Data were obtained by scanning coordinates of 36 landmarks using Microscribe G2X, and then were processed by software PAST and Morphologika2 using multivariate statistics (PCA, MANOVA). Geometric morphometrics is used for a detailed analysis of shape changes of the mandible. There is no difference between dental and chronological age. In conclusion, lower jaw narrows during growth, the body extends more in the region of third molars and the ramus grows mainly in the region of condylar process. Chin prominence also occurs during ontogeny. In the group of adult mandibles the variability is caused by coronoid process height and the body width. The hypothesis, that age groups are significantly different from each other, and therefore due to tooth mineralization there are marked shape changes, is confirmed.
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Development of dentition in the x-ray image
STOKLASOVÁ, Martina
The topic of the bachelor thesis is to compare the quality of analogic and digital orthopantomograms. The accuracy and legibility of these x-ray photos is assessed via teeth dental age in different areas of mixed dentition at ten-year old children. Further, the thesis analyses the most commont mistakes made when orthopantomogram is taken. In the theoretic part of the thesis the anatomy is described, the development of teeth and teeth marking. Next, the thesis focuses on dental age assessing at grown ups and its methods. Further, the theoretical part describes in detail x-ray machines and techniques in stomatology. The x-ray photos of children and their preparation is a special part of the thesis. The practical part of the thesis formulates goals and research questions. A file and a metodology, which are used in the research are descibed. The dental age is assessed according to a method proposed by Kominek and Rozkovcova, 1984. This method lies in compartmentalization of a developing dental germ of 7 developing stages corresponging with a specific age period. A permanent and a temporary dentures are assessed in schemes and tables and devided according to the development stage of a child. The research of the thesis lied in assessing and comparing of dental age within a file of 100 children with mixed dentition at the age of ten years. The file comprised 50 randomly chosen analogic photos and 50 digital photos. Further, technical mistakes at the photos and the their reasons were assessed and analyzed. The thesis descibes examples of assessing both of analogic photos and digital photos and the mistakes which inable the dentition development assessing. Its clear that digital photos is more accurate and of a higher quality. Thus, its suprising how many mistakes were found on the chosen photos. From today's point of view, analogic photos are a past. Analogic photos showed frequent flaws in quality, such as insufficiant photos development causing artefacts, over- and underlighting, insufficiant settling on the photos. A disadvantage of this way of development were also huge area demands for development of an analogic photos and the necessity of storing of chemicals and films. Paradoxically, in the results of the thesis more mistakes were found on digital rather than on analogic photos in a random choice, which seems a serious problem to me because modern digital methods cannot be compared to history photos as far as their technical possibilities are concerned. When assesing the accuracy of results of the dental age of children, we can find out how many photos can be assessed and how many not. On 20 randomly chosen digital and 20 analogical photos an analysis of the most common mistakes in orthopantomographs was carried out. For the analysis of the mistakes on the photos a frontal part of the denture was chosen, which is the area of the cutters where the most mistakes were cause by incorrect setting of the children's head in the x-ray machine. On 20 analogical photos, 35% of the children were placed in the machine incorrectly, on 20 digital photos the result was 25% of the children. When comparing analogical and digital photos, no difference was found when assessing the dental age. The discussion shows the importance of making orthopantomograph in a high quality at children in the period of denture change and the most common mistakes are commented on. In conclusion, the problematics of orthopantomograph making was summed up, where the most common flaws when making x-ray photos at children were pointed out. These flaws lead to diagnostic inaccuracies. The importance of correct placing of the child when x-ray making was stressed, which was not adhered to at 55% of the children patients whose photos I assessed. This fact is to be taken very seriously because it is an invasive checkup.
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Age estimation in two recent European population by assessment of permanent tooth mineralization
Černá, Magdaléna ; Velemínská, Jana (advisor) ; Stránská, Petra (referee)
Age estimation is a common requirement in forensic, bioarcheological and biomedical practice. This master thesis deals with age estimation based on permanent tooth mineralization according to Demirjian et al. (1973). The research material consisted of orthopantomograms of 716 Czech and 743 French children aged between 4 and 15 years. The purpose of this study was to analyse the suitability of the original French-Canadian standards for age estimation (Demirjian a Goldstein, 1976) and the recent Belgian standards (Willems et al., 2001) in Czech and French population. Another aim of the study was to evaluate the accuracy of the neural network method that represents a completely new approach in data prediction. In order to express the accuracy of estimate we used mean and median of difference between chronological and dental age, and RMS error. Using logistic regression, differences in tooth mineralization between Czech and French population and between girls and boys were also evaluated. Our results indicate that the French-Canadian standards gave a consistent overestimation of dental age compared with chronological age. Mean difference was 0,33 years for Czech children and 0,45 and 0,46 years for French girls and boys, respectively. We found that Willem's method and neural network method were more...
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Possibilities and limits of auxological studies in past populations
Suchanová, Gabriela ; Velemínská, Jana (advisor) ; Sedlak, Petr (referee)
Auxological studies in bioarcheology provide valuable information about the health of children in past populations. They show the influence of various environmnetal factors, non- specific stress or illness during growth. The stress following the growth retardation of subadults who survive until adulthood will influence the function and general health of the entire population. Despite all the achieved results in this field, auxological studies comprise of many problems. It is necessary to remember that the archaeological samples of children who died of unknown reasons are compared with modern growth standards, also the secular trend of recent population needs to be allowed for. The question is whereas the growth of children who died prematurely represents accuretly the growth of those who survived until adulthood. Of importance is a precise estimation of age of subadult skeletons. To minimalize faults associated to paleoauxological studies in bioarchaeology, it is necessary to compare the samples of related populations where possible, use the same techniques of age-at-death estimation, take account of migrations and so on.
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Age estimation based on human dentice
Černá, Magdaléna ; Velemínská, Jana (advisor) ; Brůžek, Jaroslav (referee)
Age estimation plays a very important role not only in forensic and biomedicinal anthropology, but also in other disciplines, such as bioarcheologie or paleoanthropology. Teeth are considered the most reliable age indicators during childhood and adolescence. Teeth are resistant to the effects of external and internal factors, and because of that they decay a long time after a death of an individual. While age estimation in children and adolescents can be based on mineralization or eruption of the teeth, in adults it is focused on retrogressive changes in dentition. There have been established several methods and their modification for age assessment based on these criteria. This thesis aims to generally summarize tthe principles and methods of age estimation based on dentition both in immature and adult individuals.
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Utilization of forensic dentistry in indentification of individuals
Fialková, Martina ; Velemínská, Jana (advisor) ; Stránská, Petra (referee)
Forensic identification and age estimation has a significant role in cases when the unknown deceased body is found, after mass disasters when it is necessary to distinguish victims, but also in guestion of imigrants. And just these areas are very important part of forensic odontology, because dental development like a complex proces takes place from early foetal life to approximately 20 years of age is less affected by endocrine diseases or nutritional variations than other tissues. Dental age estimate is fundamental mainly in cases of children and young people, which teeth are still growing and they are in different developmental stages. On basis of these stages is possible to obtain very accurate results.
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Evaluation of ontogenetic development of the mandible using geometric morphometric methods
Kiebelová, Alena ; Velemínská, Jana (advisor) ; Brůžek, Jaroslav (referee)
During ontogeny there are a lot of changes in the entire human skeleton. This thesis deals with shape changes in the mandible, which are caused by genetic, hormonal, as well as mechanical factors. The most important mechanical factors influencing the shape of mandible are development of deciduous and permanent dentition and also development of masticatory muscles. 34 children mandibles of known age and 14 adult mandibles were analysed and compared for this thesis. Data were obtained by scanning coordinates of 36 landmarks using Microscribe G2X, and then were processed by software PAST and Morphologika2 using multivariate statistics (PCA, MANOVA). Geometric morphometrics is used for a detailed analysis of shape changes of the mandible. There is no difference between dental and chronological age. In conclusion, lower jaw narrows during growth, the body extends more in the region of third molars and the ramus grows mainly in the region of condylar process. Chin prominence also occurs during ontogeny. In the group of adult mandibles the variability is caused by coronoid process height and the body width. The hypothesis, that age groups are significantly different from each other, and therefore due to tooth mineralization there are marked shape changes, is confirmed.
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