A configuração e o formato das estruturas craniofaciais, a oclusão dentária, a musculatura orofacial bem como a harmonia facial são determinantes para as características próprias da face humana. Instrumentos manuais como paquímetro e fitas métricas têm sido tradicionalmente utilizados para realizar as medidas antropométricas, diretamente de um sujeito em ambiente clínico. O avanço tecnológico possibilitou transformar a aquisição destas medidas analógicas em medições digitais, tornando possível aquisições rápidas, precisas e sem radiação. Tais informações podem, ainda, ser arquivadas para futuras análises e compartilhamento de informações com colegas e pacientes. A estereofotogrametria tem se destacado dentre as novas técnicas de captação de imagens tridimensionais, onde um grupo de câmeras de rápida captura fotografam a imagem do indivíduo a partir de variadas angulações. Atualmente, sistemas portáteis de estereofotogrametria vêm sendo propostos no mercado por apresentarem maior praticidade e simplicidade no manuseio. A proposta do presente estudo foi avaliar a precisão e a reprodutibilidade de um sistema de estereofotogrametria 3D portátil (Vectra H1, Canfield Scientific, Fairfield, NJ, EUA) em medições dos tecidos moles faciais de 30 participantes e de um cubo de medidas definidas, comparando tais medidas com as obtidas por um sistema de estereofotogrametria 3D fixo (Vectra M3, Canfield Scientific, Fairfield, NJ, EUA), de precisão e reprodutibilidade estabelecidas e validadas, através de análise quantitativa dos possíveis erros. Foram realizadas marcações craniométricas transitórias em tecido mole da face nos 30 participantes do estudo (n=30), sendo estes submetidos à aquisição de imagens pela técnica da estereofotogrametria, tanto pelo sistema fixo Vectra M3, quanto pelo sistema portátil Vectra H1. Trinta pontos de referência (landmarks) foram utilizados para realizar as medidas (em mm) de 34 distâncias. Quanto ao cubo, foram avaliados, no total, 20 ângulos, 20 áreas e 9 distâncias lineares. Os resultados obtidos pela metodologia estabelecida, juntamente com a correlação aos achados da literatura, permitiram concluir que o sistema portátil Vectra H1 apresentou precisão e repetibilidade comparáveis com o sistema fixo Vectra M3, evidenciando sua capacidade de capturar imagens tridimensionais de modo eficaz, o que torna viável seu uso nas mais diversas aplicações clínicas / The human face presents characteristics according to dental occlusion, facial harmony, orofacial musculature, besides the format and configuration of craniofacial structures. Traditionally, anthropometric measurements have been acquired through direct measurements of a subject inside clinical environment, using calipers and metric tapes to measure distance between arches and landmarks. Along with scientific breakthrough, the data, used to be analogic, became digital. It opened the possibility of quick, precise and radiation-free acquisitions, with its details being simultaneously archived for future analysis and being able to be easily shared with patients and colleagues. Among new facial analysis methods the stereophotogrammetry technique has emerged, where a group of cameras with fast acquisition take photographs of the subject from multiple angles. Nowadays, portable stereophotogrammetric are being proposed, as they are more practical and easy to use. The aim of this work was analyze the accuracy and reproducibility of a portable 3D stereophotogrammetric system (Vectra H1, Candield, Fairfeld, NJ, USA) in measurements of facial soft tissue of 30 participants and defined measures of a cube, comparing these measurements with those obtained by a set 3D stereophotogrammetric system (Vectra M3, Candield, Fairfeld, NJ, USA), which has it\'s accuracy and reproducibility previously validated, through quantitative analysis of possible errors. Thirty temporary landmarks were used to make the measurements (in mm) of 34 distances in 30 participants (n=30). Regarding the cube, 20 angles, 20 areas and 9 linear distances were evaluated. The obtained results by the established methodology, along with the correlation to literature findings, allowed us to conclude that the Vectra H1 portable system has shown accuracy and reproducibility as good as the Vectra M3 set system, evidencing it\'s capability to reliably capture tridimensional images, what makes practicable it\'s use in the most diverse clinical applications

A face humana apresenta características próprias de acordo com a oclusão dentária, harmonia facial, musculatura orofacial, além do formato e configuração das estruturas craniofaciais. Tradicionalmente, medidas antropométricas têm sido adquiridas através de medições diretas de um sujeito em ambiente clínico, utilizando-se de compassos e fita métrica para medir distâncias ou arcos entre pontos de referência. Com o avanço científico e tecnológico, os dados anteriormente analógicos passaram então a ser digitais. Isto abriu a possibilidade de aquisição rápida, precisa e sem radiação, com suas informações sendo simultaneamente arquivadas para análises futuras e podendo ser compartilhadas facilmente com pacientes e colegas. Dentre as novas modalidades de análise facial a técnica da estereofotogrametria tem se destacado, onde um grupo de câmeras de captura rápida fotografam o sujeito a partir de múltiplos ângulos. O objetivo desse trabalho foi analisar o perfil facial de um grupo de jovens adultos brasileiros assintomáticos para Disfunções Temporomandibulares (DTMs), com idade entre 18 e 30 anos através da técnica da estereofotogrametria, definindo características faciais comuns a este grupo, criar um banco de dados de mensurações faciais de uma parcela da população brasileira adulta jovem saudável para uso em futuros estudos complementares e testar a precisão e repetibilidade do aparelho Vectra M3®. Participaram do estudo 60 brasileiros adultos jovens sem DTM, sendo 30 homens (GH) e 30 mulheres (GM). O diagnóstico da DTM foi realizado com o Research Diagnostic Criteria For Temporomandibular Disorders (RDC/TMD). Após avaliação Odontológica inicial, foram realizadas marcações craniométricas transitórias em tecido mole e estes sujeitos foram submetidos à aquisição de imagens pela técnica da estereofotogrametria. Trinta e um pontos de referência (landmarks) foram utilizadas para realizar as medidas (em mm) de 42 distâncias. A repetibilidade do aparelho foi testada em 20% da amostra (12 sujeitos), não havendo diferença estatisticamente significante (p>0,05) em nenhuma das 42 distâncias entre a primeira e a segunda aquisição. Os resultados obtidos possibilitaram a criação de um banco de dados de mensurações faciais de uma parcela população brasileira jovem saudável. As distâncias Tr-N, N-Sn, Tr-G, Ls-Sto, Sto-Li, En[r]-En[l] e Prn-Sn não mostraram-se estatisticamente diferentes entre os grupos GH e GM, sendo que as outras 35 medidas apresentaram-se significantemente maiores no grupo GH. O aparelho de estereofotogrametria Vectra M3® mostrou alto grau de precisão e repetibilidade. / The human face presents characteristics according to dental occlusion, facial harmony, orofacial musculature, besides the format and configuration of craniofacial structures. Traditionally, anthropometric measurements have been acquired through direct measurements of a subject inside clinical environment, using calipers and metric tapes to measure distance between arches and landmarks. Along with scientific breakthrough, the data, used to be analogic, became digital. It opened the possibility of quick, precise and radiation-free acquisitions, with its details being simultaneously archived for future analysis and being able to be easily shared with patients and colleagues. Among new facial analysis methods the stereophotogrammetry technique has emerged, where a group of cameras with fast acquisition take photographs of the subject from multiple angles. The aim of this work was analyze the anthropometric profile of a group consisted of young Brazilian adults without symptoms of Temporomandibular Disorders (TMDs), aged between 18 and 30 years old, defining facial characteristics that are common to them, create a database of facial measurements for a portion of a young healthy Brazilian population to be used in future works and test the precision and repeatability of the Vectra M3® equipment. 60 young adult Brazilians without TMD participated in this study, 30 males and 30 females. The TMD diagnose was accomplished with the Research Diagnostic Criteria For Temporomandibular Disorders (RDC/TMD). After early Odontological exam, temporary craniometrical landmarks were performed in soft tissue and those subjects underwent to imaging acquisition by the stereophotogrammetry technique. 31 landmarks were used to make the measurements (in mm) of 42 distances. The equipment repeatability was tested in 20% of the sample (12 subjects), not having statistically significant difference (p>0.05) in none of the 42 distances between first and second acquisitions. The obtained results allowed the creation of a database containing facial distances of a portion of a young healthy Brazilian population. The distances Tr-N, N-Sn, Tr-G, Ls-Sto, Sto-Li, En[r]-En[l] e Prn-Sn didn\'t show statistical difference between the group GH and GM, while the other 35 distances were significantly greater in GH. The equipment Vectra M3® showed a high level of precision and repeatability.

A face humana apresenta características próprias de acordo com a oclusão dentária, harmonia facial, musculatura orofacial, além do formato e configuração das estruturas craniofaciais. Tradicionalmente, medidas antropométricas têm sido adquiridas através de medições diretas de um sujeito em ambiente clínico, utilizando-se de compassos e fita métrica para medir distâncias ou arcos entre pontos de referência. Com o avanço científico e tecnológico, os dados anteriormente analógicos passaram então a ser digitais. Isto abriu a possibilidade de aquisição rápida, precisa e sem radiação, com suas informações sendo simultaneamente arquivadas para análises futuras e podendo ser compartilhadas facilmente com pacientes e colegas. Dentre as novas modalidades de análise facial a técnica da estereofotogrametria tem se destacado, onde um grupo de câmeras de captura rápida fotografam o sujeito a partir de múltiplos ângulos. O objetivo desse trabalho foi analisar o perfil facial de um grupo de jovens adultos brasileiros assintomáticos para Disfunções Temporomandibulares (DTMs), com idade entre 18 e 30 anos através da técnica da estereofotogrametria, definindo características faciais comuns a este grupo, criar um banco de dados de mensurações faciais de uma parcela da população brasileira adulta jovem saudável para uso em futuros estudos complementares e testar a precisão e repetibilidade do aparelho Vectra M3®. Participaram do estudo 60 brasileiros adultos jovens sem DTM, sendo 30 homens (GH) e 30 mulheres (GM). O diagnóstico da DTM foi realizado com o Research Diagnostic Criteria For Temporomandibular Disorders (RDC/TMD). Após avaliação Odontológica inicial, foram realizadas marcações craniométricas transitórias em tecido mole e estes sujeitos foram submetidos à aquisição de imagens pela técnica da estereofotogrametria. Trinta e um pontos de referência (landmarks) foram utilizadas para realizar as medidas (em mm) de 42 distâncias. A repetibilidade do aparelho foi testada em 20% da amostra (12 sujeitos), não havendo diferença estatisticamente significante (p>0,05) em nenhuma das 42 distâncias entre a primeira e a segunda aquisição. Os resultados obtidos possibilitaram a criação de um banco de dados de mensurações faciais de uma parcela população brasileira jovem saudável. As distâncias Tr-N, N-Sn, Tr-G, Ls-Sto, Sto-Li, En[r]-En[l] e Prn-Sn não mostraram-se estatisticamente diferentes entre os grupos GH e GM, sendo que as outras 35 medidas apresentaram-se significantemente maiores no grupo GH. O aparelho de estereofotogrametria Vectra M3® mostrou alto grau de precisão e repetibilidade. / The human face presents characteristics according to dental occlusion, facial harmony, orofacial musculature, besides the format and configuration of craniofacial structures. Traditionally, anthropometric measurements have been acquired through direct measurements of a subject inside clinical environment, using calipers and metric tapes to measure distance between arches and landmarks. Along with scientific breakthrough, the data, used to be analogic, became digital. It opened the possibility of quick, precise and radiation-free acquisitions, with its details being simultaneously archived for future analysis and being able to be easily shared with patients and colleagues. Among new facial analysis methods the stereophotogrammetry technique has emerged, where a group of cameras with fast acquisition take photographs of the subject from multiple angles. The aim of this work was analyze the anthropometric profile of a group consisted of young Brazilian adults without symptoms of Temporomandibular Disorders (TMDs), aged between 18 and 30 years old, defining facial characteristics that are common to them, create a database of facial measurements for a portion of a young healthy Brazilian population to be used in future works and test the precision and repeatability of the Vectra M3® equipment. 60 young adult Brazilians without TMD participated in this study, 30 males and 30 females. The TMD diagnose was accomplished with the Research Diagnostic Criteria For Temporomandibular Disorders (RDC/TMD). After early Odontological exam, temporary craniometrical landmarks were performed in soft tissue and those subjects underwent to imaging acquisition by the stereophotogrammetry technique. 31 landmarks were used to make the measurements (in mm) of 42 distances. The equipment repeatability was tested in 20% of the sample (12 subjects), not having statistically significant difference (p>0.05) in none of the 42 distances between first and second acquisitions. The obtained results allowed the creation of a database containing facial distances of a portion of a young healthy Brazilian population. The distances Tr-N, N-Sn, Tr-G, Ls-Sto, Sto-Li, En[r]-En[l] e Prn-Sn didn\'t show statistical difference between the group GH and GM, while the other 35 distances were significantly greater in GH. The equipment Vectra M3® showed a high level of precision and repeatability.

O objetivo deste estudo foi determinar as variações de volume pós-operatórias associadas à cirurgia ortognática, com base nas variáveis tempo, gênero, idade e lado da face. Foram avaliadas fotografias tridimensionais de dezoito pacientes submetidos simultaneamente às osteotomias Le Fort I e sagital do ramo mandibular bilateral. As imagens foram obtidas por meio do aparelho Vectra® M3 (Canfield, NJ, EUA) e capturadas nos períodos pós-operatórios de: uma semana (1S), um mês (1M), dois meses (2M), seis meses (6M) e um ano (1A). A foto obtida no período 1A foi utilizada como base de comparação para as demais (1S, 1M, 2M e 6M). O maior volume facial foi observado 1 semana após a realização da cirurgia ortognática (47,11 cm3, DP = 30,5 cm3), e neste período os homens apresentaram valores mais elevados (67,27 cm3, DP = 33,54 cm3) em relação as mulheres (30,98 cm3, DP = 15,25 cm3) e o lado direito (26,58 cm3, DP = 17,22 cm3) maior que o esquerdo (20,52 cm3, DP = 14,93 cm3). A regressão do volume mais expressiva ocorreu entre a primeira semana e o primeiro mês de pós-operatório (58,9%). Não foram observadas diferenças significantes entre as faixas etárias analisadas. / The purpose of this retrospective study was to determine postoperative volume differences associated with orthognathic surgery, controlling for time, gender, age and side of face. Three-dimensional (3D) photographs were analyzed of eighteen patients submitted to simultaneous Le Fort I + Bilateral Sagittal Split osteotomies. The images were obtained using a Vectra® M3 device (Canfield, NJ, USA) and were captured postoperatively, at one week (1S), one month (1M), two months (2M), six months (6M) and one year (1A). The photo taken at 1A was used as the basis of comparison for the other photos (1S, 1M, 2M, 6M). Greatest facial volume was observed at one week after surgery (47,11 cm3, DP = 30,5 cm3), with men in this period showing higher values (67,27 cm3, DP = 33,54 cm3) than women (30,98 cm3, DP = 15,25 cm3) and the right side (26,58 cm3, DP = 17,22 cm3) higher than the left (20,52 cm3, DP = 14,93 cm3). The most extensive facial volume resolution occurred between the first week and the first month; postoperatively (58,9%). No significant difference was found between age groups.

O objetivo deste estudo foi determinar as variações de volume pós-operatórias associadas à cirurgia ortognática, com base nas variáveis tempo, gênero, idade e lado da face. Foram avaliadas fotografias tridimensionais de dezoito pacientes submetidos simultaneamente às osteotomias Le Fort I e sagital do ramo mandibular bilateral. As imagens foram obtidas por meio do aparelho Vectra® M3 (Canfield, NJ, EUA) e capturadas nos períodos pós-operatórios de: uma semana (1S), um mês (1M), dois meses (2M), seis meses (6M) e um ano (1A). A foto obtida no período 1A foi utilizada como base de comparação para as demais (1S, 1M, 2M e 6M). O maior volume facial foi observado 1 semana após a realização da cirurgia ortognática (47,11 cm3, DP = 30,5 cm3), e neste período os homens apresentaram valores mais elevados (67,27 cm3, DP = 33,54 cm3) em relação as mulheres (30,98 cm3, DP = 15,25 cm3) e o lado direito (26,58 cm3, DP = 17,22 cm3) maior que o esquerdo (20,52 cm3, DP = 14,93 cm3). A regressão do volume mais expressiva ocorreu entre a primeira semana e o primeiro mês de pós-operatório (58,9%). Não foram observadas diferenças significantes entre as faixas etárias analisadas. / The purpose of this retrospective study was to determine postoperative volume differences associated with orthognathic surgery, controlling for time, gender, age and side of face. Three-dimensional (3D) photographs were analyzed of eighteen patients submitted to simultaneous Le Fort I + Bilateral Sagittal Split osteotomies. The images were obtained using a Vectra® M3 device (Canfield, NJ, USA) and were captured postoperatively, at one week (1S), one month (1M), two months (2M), six months (6M) and one year (1A). The photo taken at 1A was used as the basis of comparison for the other photos (1S, 1M, 2M, 6M). Greatest facial volume was observed at one week after surgery (47,11 cm3, DP = 30,5 cm3), with men in this period showing higher values (67,27 cm3, DP = 33,54 cm3) than women (30,98 cm3, DP = 15,25 cm3) and the right side (26,58 cm3, DP = 17,22 cm3) higher than the left (20,52 cm3, DP = 14,93 cm3). The most extensive facial volume resolution occurred between the first week and the first month; postoperatively (58,9%). No significant difference was found between age groups.

Magister Scientiae Dentium - MSc(Dent) / The research is aimed at investigating and finding alternatives to the physical necessity of producing and storing plaster casts or stone models of the tissues of the mouth. The quest for time and space is universal and the successful management of both results in stress free, financially stable and uncluttered work circumstances. Study models do playa very important role in diagnostics and treatment planning as well as communicating final results in Dentistry, especially in Orthodontic practice. Conventional study models are bulky, fragile, and expensive diagnostic tools produced from impressions taken of the patient's mouth and cast in plaster or stone. The storage of these records creates major space problems, and recalling or retrieving models at some later stage also causes logistical problems. Ideally, the tissues of the mouth could be scanned and from this a 3-D image produced on screen, which could later be milled (machining process of reproducing, explained in Appendix B) if necessary. Three dimensionally accurate, visually pleasing, reproducible, measurable and retrievable records, would be the solution. Computerizing dental records has already revolutionized the industry in the fields of Radiology and written patient data. This information is available at the click of a mouse, and integrated diagnostic tools can be displayed on screen. A thorough investigation of all methods of capturing dental data and 3D images from previously researched and publicized studies was conducted before attempting the latest technology. The final project involved: 1. requesting an introductory and explanatory demonstration on the scanning possibilities in South Africa 2. organizing and attending a demonstration of the laser and contact scanner on study models and impressions. 3. undergoing training in the use of a contact scanner. Computerizing of these results and comparing data derived from analyzing both study models and impressions, manually and digitally. 4. researching and collecting of data with engineering professionals, to establish the validity and viability of this method ( aiming to use uncomplicated, widely accepted and thoroughly applicable basic criteria in all experiments.) 5. evaluation of data statistically by a statistician. Discussion: Digitizing and computerizing of images derived from scanning the models or impressions offers the most attractive alternative for record keeping. Laser scanning disappointed in general due to the relative unavailability in South Africa, the expensive nature of the service elsewhere and limiting factors due to the sensitivity of the laser beam. It is the most promising alternative in future research, because of improved accuracy, higher speed of scanning, uniformity and reproducibility. Contact scanning proved to be available, reliable and adjustable. In most applications, the best results in terms of accuracy and quality of surface finish are obtained using contact scanning. The disadvantage of this method is the time factor and therefore it becomes expensive and economically not viable. The direct scanning of impressions, albeit with laser or contact scanning, remains a scientific and clinical viable option. Conclusion: Digital imaging is still a young technology and many aspects are not yet completely explored. It is a promising technology and its significance is increasing because it opens the door to diagnostic information. Another important development is that the software for digital imaging will become more integrated with other computerized dental applications in the dental office, enabling patient data between different and remote practices to be exchanged more easily. Further progress is not limited by a lack of available image processing tools but rather by our restricted understanding of the various components of diagnostic imaging in dentistry. A Bioengineering exhibition mounted by the University of Munich during a December 2000 conference, displayed a specially adapted CT Scanner that could scan information directly from the mouth. This leads to more possibilities of deriving images without impressions or study casts.

The annals of orthodontics are filled with studies aimed to understand how extraction orthodontic treatment might change the face. Although many studies have addressed profile changes due to extraction treatment, fewer studies have focused on how extractions change a patients smile. With the advent of surface imaging systems such as 3dMD, it is now possible to visualize the smile, and any changes incurred during orthodontic treatment, in three dimensions. Subjects for this study were chosen from the pool of 11-18 year old patients treated at the Podray Orthodontic Clinic at the Temple University Kornberg School of Dentistry. Subjects were Cl II patients, and must have been treated with either extraction of any combination of premolars or treated without extraction. Subjects were divided into four experimental groups based on two characteristics- mandibular angle (those with angles greater than 28o versus those with angles less than 28o) and treatment (extraction versus non-extraction). The resulting groups were separated as follows: high-angle extraction patients (n=8), low-angle extraction patients (n=6), high-angle non-extraction patients (n=7), and low-angle non-extraction patients (n=15). For each subject initial and final 3dMD images were superimposed using 3dMD Vultus software. A color histogram was constructed to visualize changes during treatment. The cheeks, commissures, upper and lower lips, chin, and nose, were also landmarked, and the changes in these landmarks were calculated. Volume changes were also calculated between pre and post treatment 3D data. Results showed that the lower lip and right commissure changes between high-angle extraction and non-extraction groups were statistically significant. A qualitative analysis of the histograms further supported these findings. In general, a greater change in soft tissue landmarks and soft tissue volumes could be seen in high-angle patients than low-angle patients. Differences in the changes that result from treatment type (extraction vs. non-extraction) were seen in the high-angle group. In contrast, similar changes result from treatment type (extraction vs. non-extraction) in the low-angle groups. Furthermore, the lip changes seen in extraction patients upon smiling are very similar to those changes seen in the same patient in repose. Most interestingly, soft tissue differences of the face due to treatment, growth, or both, seem to disappear upon smiling, with the exception of the lips. Qualitative assessment of these changes in the smile might be a more appropriate method for identifying soft tissue changes than statistical analyses. Similar studies with larger sample sizes are a promising direction for future research. / Oral Biology

The purpose of this work is to study phenotypic craniofacial traits of unaffected parents of individuals with nonsyndromic cleft lip with or without palate (NSCL/P). In order to evaluate these craniofacial traits, three dimensional photographs were obtained and landmarked to compare the sample of unaffected parents with a control sample. The sample was comprised of 40 unaffected fathers, 25 control males, 84 unaffected mothers, and 34 control females. Twenty-four three-dimensional landmarks were exported for analysis for each subject. For the purposes of this study, nine euclidean distances were subjected to a discriminant function analysis to evaluate their ability to discriminate between an unaffected parent and a control. In both the male and female analysis, certain craniofacial measurements correctly and significantly discriminated between unaffected parents and controls. It appears that certain facial traits are subclinical markers for enhanced genetic susceptibility to nonsyndromic cleft lip with or without palate.

Vergleichende Untersuchungen zur Wiedergabegenauigkeit optoelektronischer berührungsloser und plastischer Abformungen weicher Gesichtsstrukturen Universität Leipzig, Dissertation Problemstellung: Deformation der fazialen Weichgewebe bei liegenden Patienten, hervorgerufen durch schwerkraft- und materialgewichtabhängige Einflüsse der bei konventionellen Abformmethoden verwendeten Materialien Hydrokolloiden und Elas- tomere. Ziel: Vergleich der Wiedergabegenauigkeit weicher Gesichtsstrukturen bei konven- tionellen plastischen Abformmethoden und einem optischen, mechanischen berüh- rungsfreien dreidimensionalen fotorealistischen Modell. Material und Methode: Konventionelle Abformung bei 20 Probanden mit Hydrokolloid und Elastomer sowie ein optischer Gesichtsscan vom Mittelgesicht. Studienaufbau: Digitali- sieren der Gipsmodelle und Auswertung aller STL-Datensätze zum Vergleich zwischen plastischen und optoelektronischen Abformungen sowie die Evaluation der vorhandenen Abweichungen in 34 konstruierten Punkten. Statistik: Testen auf Normalverteilung und Varianzengleichheit zum Prüfen der Signifikanz mittels Zweistichproben-t-Test und Wilcoxon-Rangsummen-Test. Ergebnisse: Der allgemeiner Abformfehler zwischen optischem Scan und konven- tionellen Abformungen liegt bei 1,19 mm ± 0,32 mm mit Variationen bei den Ma- terialien Alginat 1,02 mm ± 0,24 mm und Silikon 1,36 mm ± 0,31 mm. Signifikante Unterschiede zwischen den Abformmaterialien zeigen sich in 6 von 34 Messpunkten (p < 0,05). Alginat weist tendentiell die besseren Ergebnisse auf und ruft weniger Weichgewebsveränderung hervor. Die beschriebenen Differenzen entstehen durch die Deformation der Weichgewebe bei der Gesichtsabformung. Bei den Punkten ohne statistische Signifikanz ist die Abformtechnik als sehr präzise zu betrachten. In gut skelettal-unterstützten Regionen zeigt Silikon in einigen Messpunkten geringere Abweichungen. Schlussfolgerung: Die Auswahl des Abformmaterials sollte in Abhängigkeit von der Ausgangssituation gewählt werden. Trotz der modifizierten Abformtechnik zeigen die Ergebnisse einen deutlichen Unterschied zwischen digital erfasstem dreidimensionalem Gesichtsscan und konventionellen Abformmethoden. Den optischen Systemen ist derzeit der Vorzug zu geben. Die Vorteile sind hinsichtlich noninvasiver, iterierender Aufnahmen, genauerer und effektiverer Analyse sowie CAD/CAM-Herstellung von Epithesen aus biokompatiblen Werkstoffen beachtlich.

The underground limestone mining industry is a small, but growing segment of the U.S. crushed stone industry. However, its fatality rate has been amongst the highest of the mining sector in recent years due to ground control issues related to ground collapses. It is therefore important to improve the engineering design, monitoring and visualization of ground control by utilizing new technologies that can help an underground limestone company maintain a safe and productive operation. Photogrammetry and laser scanning are remote sensing technologies that are useful tools for collecting three-dimensional spatial data with high levels of precision for many types of mining applications. Due to the reality of budget constraints for many underground stone mining operations, this research concentrates on photogrammetry as a more accessible technology for the average operation. Despite the challenging lighting conditions and size of underground limestone mines that has previous hindered photogrammetric surveys in these environments, over 13,000 photographic images were taken over a 3-year period in active mines to compile these models. This research summarizes that work and highlights the many applications of terrestrial close-range photogrammetry, including practical methodologies for implementing the techniques in working operations to better visualize hazards and pragmatic approaches for geotechnical analysis, improved engineering design and monitoring. / M.S. / The underground limestone mining industry is a small, but growing segment of the U.S. crushed stone industry. However, its fatality rate has been amongst the highest of the mining sector in recent years due to ground control issues related to ground collapses. It is therefore important to improve the engineering design, monitoring and visualization of ground control by utilizing new technologies that can help maintain safe and productive underground stone operations. Photogrammetry and laser scanning are remote sensing technologies that are useful tools for collecting three-dimensional spatial data with high levels of precision for many different mining applications. Due to the reality of budget constraints for many mining operations, this research concentrates on photogrammetry as a more accessible technology for the average operation, despite the challenging lighting conditions and expansive size of underground limestone mines that has previous hindered photogrammetric surveys in these environments. This research focuses on the applications of photogrammetry in underground stone mines and practical methodologies for implementing the techniques in working operations to better visualize hazards for improved engineering design and infrastructure management.