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Variabilita a vývojové změny obličeje člověka ve věku 3-15 let: longitudinální a transverzální přístup / Variability and developmental changes of human face between 3 and 15 years: longitudinal and transversal approachMoštková, Miroslava January 2018 (has links)
- 1 - Abstract The intent of this thesis is to evaluate the differences in facial morphology of children between 3 and 15 years of age based on 3D facial models and cross-sectional data. Due to improper use of cross-sectional data for studying growth, the next part of the thesis is focused on the comparison of cross-sectional and longitudinal approaches in research. The longitudinal observation of facial developmental changes can be considered as actual growth. The cross-sectional database contains 839 3D facial models (397 boys, 442 girls). Three previously published longitudinal databases were used for comparison. Their age intervals were as follows: 3 to 6 years (12 boys, 14 girls), 6 to 12 years (15 boys, 18 girls), 12 to 15 years (23 boys, 22 girls). Geometric morphometric methods were used to analyse facial models (Coherent Point Drift - Dense Correspondance Analysis, Per Vertex T-Test and Principal Component Analysis). The results were visualized using superimposition colour maps, shell distance significance maps and their interlacing. When annual consecutive age intervals were used for cross-sectional data, we could not observe the fluency of differences in facial morphology between age categories, which we can observe during actual growth. When wider age intervals were used for cross-sectional...
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Odhad pohlaví lebky podle povrchu exokrania s využitím CT skenů / Sex assessment of skull using exocranial meshes from CT scansMusilová, Barbora January 2015 (has links)
Sex estimation is a challenging problem in both forensic anthropology and bioarchaeology. Sexual dimorphism is most noticeably displayed by the pelvis; however in instances when it is not preserved, sex is estimated by skull. There is a multitude of approaches that use the skull, however, their population specificity and variable sexual dimorphism oscillation reduces their effectiveness (Bruzek and Murail, 2006). We base our contribution on the study by Abdel Fatah et al. (2014) that estimates sex based on exocranial and endocranial surfaces with a high success rate of 97%. Our approach uses anonymized CT scans of skulls from recent french population, from which the exocranial surface was segmented. On these surfaces, CPD-DCA (Dupej et al., 2014) was performed. We analyzed both form and shape (form after size normalization) of these surfaces in 104 skulls (53 males, 51 females) aged 18 to 92 years. The mean age was 58 years in females and 52.46 years in males. Classification was performed using support vector machines (SVM) with a radial kernel. Leave-one-out crossvalidation was also applied. The highest success rate (87.5 %) was achieved with the first 27 principal components of form. Classification of shape was less accurate by only 2 %. Even though our success rate was lower than that of Abdel...
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3D morfometrická analýza obličeje pacientů s Williamsovým, Noonanové a DiGeorgeovým syndromem / 3D morphometric facial analysis in Williams, Noonan and DiGeorge syndrome patientsČaplovičová, Martina January 2016 (has links)
The aim of the thesis was to evaluate facial dysmorphism in Williams (WBS), Noonan (NS) and DiGeorge syndrome (DGS) patients and also to evaluate changes in the morphology of the face during growth. In total 57 3D facial scans of patients of all ages were analysed, including 12 WBS, 20 NS, 25 DGS and 31 scans of control subjects. The evaluation has been carried out using methods of geometric morphometry, namely by coherent point drift - dense correspondence analysis, superprojection of mean faces, per vertex t-test and principal component analysis. Statistically significant differences in the facial morphology were shown for all the syndromes vs. control. Observed dysmorphies in WBS (narrow forehead, bitemporal narrowing, periorbital fullness, bulbous and anteverted nasal tip, malar flattening, protrusion of both lips, pointed chin) mostly confirmed existing knowledge of the typical phenotype. The morphology in WBS is thus strongly specific and manifested in most of the patients. During ontogeny, the dysmorphic features associated with increased facial convexity become pronounced, while the other typical features remain relatively stable. In contrast to the control, the retrusion of the chin occurs during the development. Observed dysmorphic traits in NS (less prominent supraorbital ridges,...
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Morfologie dolní čelisti s ohledem na demografickou strukturu raně středověkého pohřebiště Mikulčice / Morphology of the mandible with regard to the demographic structure of the early medieval burial area MikulčiceThon, Tomáš January 2020 (has links)
This Master's thesis focuses on the influence of socioeconomic status on the morphology of the mandible of individuals from the early medieval burial area in Mikulčice. This hillfort was an important center of power of the Great Moravian Empire with a stratified society. This work compares 2 different approaches on how to divide the inhabitants. The first of them is the division of individuals according to the location of graves into individuals from the castle, sub-castle, and hinterland. The second approach is the division of individuals according to the richness of grave equipment into individuals with rich and poor grave equipment. A different social status is associated mainly with different diets. Therefore, the attachments of the masticatory muscles are the most affected areas. A total of 132 individuals (59 males and 73 females) were analyzed. The material was evaluated by methods of geometric morphometrics. The used methods were CDP DCA, GPA, two-sample t-test, PCA, MANOVA, and SVM. Sexual dimorphism was observed in all sub-groups of the Mikulčice population. Men have larger mandibles with rami wider apart. The biggest differences are between individuals from the castle, the smallest between individuals with rich grave equipment. The distribution of individuals based on the location of...
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Hodnocení morfologie obličeje pacientů s orofaciálními rozštěpy v návaznosti na terapeutické postupy. / Assessment of facial morphology in patients with orofacial clefts in relation to surgical protocolsMoslerová, Veronika January 2018 (has links)
The presented thesis summarizes the results of research on craniofacial morphology in patients with facial cleft defects in relation to therapeutic approaches (Caganova et al., 2014; Dadáková et al., 2016; Hoffmannova et al., 2016; Hoffmannova et al., 2018; Moslerová et al., 2018). The effect of therapy in individuals with pathological growth disorders cannot be evaluated without detailed auxological studies of control subjects whose facial morphology, longitudinal changes, or manifestations of sexual dimorphism were evaluated upon similar methodology (Koudelová et al. 2015). Therefore, the thesis was conceived as a volume of six publications complemented with a general synthetic introduction into the area of study. Together, the thesis includes probands in a broad age spectrum from birth to 15 years with a total of 294 facial 3D scans, 36 tele-X-ray face images, 3D scans of 112 gypsum palate castings. The methods of geometric morphometry and multidimensional statistics prevail in the assessment. The main clinical part of the thesis deals with the influence of two types of surgery on the facial growth and development of patients with cleft palate, namely secondary spongioplasty (SS) and neonatal cheiloplasty (NCH). Neonatal cheiloplasty (NCH) is the surgery whose effects were studied from several...
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Hodnocení morfologie patra u BCLP pacientů s palatoláliemi / Evaluation of the palate morphology in bilatelar cleft lip and palate clefts with palatolalyHamtilová, Martina January 2011 (has links)
The diploma work was based on the evaluation of dental casts of patients with bilateral cleft lip and palate (BCLP) with a mean age of 10. Patients consist of two groups, patients without defect in speech and with speech impairment (palatolaly). Palatolalies in the literature are primarily associated with velopharyngeal insufficiency. The study tested the working hypothesis that in the failure of speech is involved a different, specific in some way, palatal shape. Dental casts were scanned using a laser scanner and analyzed by 3-D geometric morphometry and multivariate statistics: principal component analysis (PCA), linear regression analysis and finite element analysis (FESA). Using linear regression it was found that the shape of the palate is affected in younger individuals by age, and so had to be 5 patients excluded for further analysis. Patients with palatolaly have lower variability the palatal shape than patients without palatolalie, so their palates are similar to each other and have a specific shape. Palates are wider and lower than in individuals without speech disorder and they have a characteristic deepening behind the anterior part of the palate. We assume that these features in palate morphology primarily the lower arch and the substantial deepening are most likely to affect the...
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