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https://hdl.handle.net/10784/28131

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Accuracy and reliability of mandibular digital model registration with use of the mucogingival junction as the reference
(Elsevier USA, 2018-01-01) Rey, Diego; Universidad EAFIT. Departamento de Ingeniería Mecánica; Bioingeniería GIB (CES – EAFIT)
Acoustic displacement tetrahedra developed using the IET rules
(PERGAMON-ELSEVIER SCIENCE LTD, 2010-09-01) Correa, S.; Militello, C.; Recuero, M.; Universidad EAFIT. Departamento de Ingeniería Mecánica; Bioingeniería GIB (CES – EAFIT)
A four node, displacement based, acoustic element is developed. In order to avoid spurious rotational modes, a higher order stiffness is introduced. The higher order stiffness is developed from an incompatible strain field which computes element volume changes under nodal rotational displacements fields. The higher order strain satisfies the IET requirements, non affecting convergence. The higher order stiffness is modulated, element by element, with a factor. Thus, the displacement based formulation is capable of placing the spurious rotational modes over the range of physical compressional modes that can be accurately captured by the mesh. © 2010 Elsevier Ltd. All rights reserved.
Adsorption of Cadmium Using Biochars Produced from Agro-Residues
(American Chemical Society, 2020-01-01) López J.E.; Builes S.; Heredia Salgado M.A.; Tarelho L.A.C.; Arroyave C.; Aristizábal A.; Chavez E.; Universidad EAFIT. Departamento de Ingeniería Mecánica; Bioingeniería GIB (CES – EAFIT)
Biochars have been shown as promising materials for cadmium remediation. However, the different precursors and the pyrolysis process operating conditions can yield very different surface functional groups, and as a result, different cadmium sorption mechanisms can be observed in biochars. Herein we present the results of cadmium sorption on biochars produced from the pyrolysis of different agro-residues, namely, coffee husk, quinoa straw, and oil palm kernel shell. The adsorption isotherms were used to determine the influence of the biochar's physicochemical characteristics to their sorption behavior. The biochars prepared from quinoa residues showed much higher cadmium uptakes than the other biochars. The concentration of base cations was found to be a critical factor for cadmium sorption. Although the quinoa biochars presented large uptakes, it was found that base cations were supported on the biochars and could be removed by leaching. Results from this study suggest that concentration of base cations on biochars could be used as predictors of the biochar capabilities for the removal of cadmium in aqueous solution. Copyright © 2020 American Chemical Society.
Alimentación, nutrición y salud oral
(2005-01-01) Roldan, Samuel Ignacio; Universidad EAFIT. Departamento de Ingeniería Mecánica; Bioingeniería GIB (CES – EAFIT)
Análisis Comparativo por Medio del Método de Elementos Finitos de los Esfuerzos Generados en la Articulación Temporomandibular en Tres Condiciones de Mordida
(2001-01-01) Roldan, Samuel Ignacio; Universidad EAFIT. Departamento de Ingeniería Mecánica; Bioingeniería GIB (CES – EAFIT)
Análisis con elementos finitos del efecto de la terapia con mentonera sobre la mandíbula y la articulación temporomandibular
(2002-01-01) Roldan, Samuel Ignacio; Universidad EAFIT. Departamento de Ingeniería Mecánica; Bioingeniería GIB (CES – EAFIT)
Aproximación a la representación en XML de objetos DICOM para fotografía médica digital
(Escuela de Ingeniería de Antioquia, 2007-01-01) Garcia, Alvín; Universidad EAFIT. Departamento de Ingeniería Mecánica; Bioingeniería GIB (CES – EAFIT)
Architecture and microstructure of cortical bone in reconstructed canine mandibles after bone transport distraction osteogenesis
(SPRINGER, 2011-11-01) Zapata, Uriel; Halvachs, Emily K.; Dechow, Paul C.; Elsalanty, Mohammed E.; Opperman, Lynne A.; Universidad EAFIT. Departamento de Ingeniería Mecánica; Bioingeniería GIB (CES – EAFIT)
Reconstruction of the canine mandible using bone transport distraction osteogenesis has been shown to be a suitable method for correcting segmental bone defects produced by cancer, gunshots, and trauma. Although the mechanical quality of the new regenerate cortical bone seems to be related to the mineralization process, several questions regarding the microstructural patterns of the new bony tissue remain unanswered. The purpose of this study was to quantify any microstructural differences that may exist between the regenerate and control cortical bone. Five adult American foxhound dogs underwent unilateral bone transport distraction of the mandible to repair bone defects of 30-35 mm. Animals were killed 12 weeks after the beginning of the consolidation period. Fourteen cylindrical cortical samples were extracted from the superior, medial, and inferior aspects of the lingual and buccal plates of the reconstructed aspect of the mandible, and 21 specimens were collected similarly from the contralateral aspect of the mandible. Specimens were evaluated using histomorphometric and micro-computed tomographic techniques to compare their microstructure. Except for differences in haversian canal area, histomorphometric analyses suggested no statistical differences in microstructure between regenerate and control cortical bone. Morphological evaluation suggested a consistent level of anisotropy, possibly related to the distraction vector. After 12 weeks' consolidation, bone created during bone transport distraction osteogenesis was comparable to native bone in microstructure, architecture, and mechanical properties. It is proposed that, after enough time, the properties of the regenerate bone will be identical to that of native bone. © Springer Science+Business Media, LLC 2010.
Are maximum bite forces of subjects 7 to 17 years of age related to malocclusion?
(Allen Press Inc., 2016-05-01) Roldán, S.I.; Restrepo, L.G.; Isaza, J.F.; Vélez, L.G.; Buschang, P.H.; Universidad EAFIT. Departamento de Ingeniería Mecánica; Bioingeniería GIB (CES – EAFIT)
Objective: To determine the effects of occlusion on maximum bite force of growing subjects. Materials and Methods: Incisor and first molar bite force of children and adolescents was evaluated. Four cohorts were measured annually for 3 years, starting at approximately 7, 9, 12, and 15 years of age, respectively. The initial sample included 182 females and 198 males; there were 130 subjects with normal occlusion, 111 with Class I malocclusion, and 139 with Class II malocclusion. Multilevel analyses were performed to model the growth changes and compare groups. Results: Maximum bite force increased significantly (P < .05) over time. Incisal forces peaked at 14.3 and 15.3 years of age for females and males, respectively. Maximum molar bite force peaked at 16 years for both males and females. Subjects with normal occlusion had significantly higher bite force than subjects with malocclusion. Maximum molar bite force exhibited a significant testing effect, with forces increasing 2.6 kg each year that the tests were repeated. Conclusions: Malocclusion has a detrimental effect on bite force. Changes in maximum bite force are also due to age, sex, and repeated testing.
Biomechanical characteristics of regenerated cortical bone in the canine mandible
(WILEY-BLACKWELL, 2011-07-01) Zapata, Uriel; Opperman, Lynne A.; Kontogiorgos, Elias; Elsalanty, Mohammed E.; Dechow, Paul C.; Universidad EAFIT. Departamento de Ingeniería Mecánica; Bioingeniería GIB (CES – EAFIT)
To test the mechanical properties of regenerate cortical bone created using mandibular bone transport (MBT) distraction, five adult male American foxhound dogs underwent unilateral distraction of the mandible with a novel MBT device placed to linearly repair a 30-35 mm bone defect. The animals were sacrificed 12 weeks after the beginning of the consolidation period. Fourteen cylindrical specimens were taken from the inner (lingual) and outer (buccal) plates of the reconstructed mandible and 21 control specimens were removed from the contralateral aspect of the mandible. The mechanical properties of the 35 cylindrical cortical bone specimens were assessed by using a non-destructive pulse ultrasound technique. Results showed that all of the cortical mechanical properties exhibit higher numerical values on the control side than the MBT regenerate side. In addition, both densities and the elastic moduli in the direction of maximum stiffness of the regenerate cortical bone specimens are higher on the lingual side than the buccal side. Interestingly, there is no statistical difference between elastic modulus (E1 and E2) in orthogonal directions throughout the 35 cortical specimens. The data suggest that not only is the regenerate canine cortical bone heterogeneous, but the elastic mechanical properties tend to approximate transverse isotropy at a tissue level, as opposed to control cortical bone, which is orthotropic. In addition, the elastic mechanical properties are higher not only on the control side but also in the lingual anatomical position, suggesting a stress shielding effect from the presence of the reconstruction plate. © 2011 John Wiley & Sons, Ltd.
Biomechanical Configurations of Mandibular Transport Distraction Osteogenesis Devices
(MARY ANN LIEBERT, INC, 2010-06-01) Zapata, Abraham Uriel; Universidad EAFIT. Departamento de Ingeniería Mecánica; Bioingeniería GIB (CES – EAFIT)
Biomechanical configurations of mandibular transport distraction osteogenesis devices.
(MARY ANN LIEBERT, INC, 2010-06-01) Zapata U; Elsalanty ME; Dechow PC; Opperman LA; Universidad EAFIT. Departamento de Ingeniería Mecánica; Bioingeniería GIB (CES – EAFIT)
Mandibular bone transport (MBT) distraction osteogenesis devices are used for achieving reconstruction of mandibular defects in a predictable way, with few complications, less complexity than other alternative surgical procedures, and minimal tissue morbidity. However, selection of appropriate MBT device characteristics is critical for ensuring both their mechanical soundness and their optimal distraction function for each patient's condition. This article assesses six characteristics of currently available MBT devices to characterize their design and function and to classify them in a way that assists the selection of the best device option for each clinical case. In addition, the present work provides a framework for both the biomechanical conception of new devices and the modification of existing ones.
Biomechanics of the canine mandible during bone transport distraction osteogenesis
(ASME, 2014-11-01) Zapata, Uriel; Dechow, Paul C.; Watanabe, Ikuya; Elsalanty, Mohammed E.; Opperman, Lynne A.; Universidad EAFIT. Departamento de Ingeniería Mecánica; Bioingeniería GIB (CES – EAFIT)
This study compared biomechanical patterns between finite element models (FEMs) and a fresh dog mandible tested under molar and incisal physiological loads in order to clarify the effect of the bone transport distraction osteogenesis (BTDO) surgical process. Three FEMs of dog mandibles were built in order to evaluate the effects of BTDO. The first model evaluated the mandibular response under two physiological loads resembling bite processes. In the second model, a 5.0 cm bone defect was bridged with a bone transport reconstruction plate (BTRP). In the third model, new regenerated bony tissue was incorporated within the defect to mimic the surgical process without the presence of the device. Complementarily, a mandible of a male American foxhound dog was mechanically tested in the laboratory both in the presence and absence of a BTRP, and mechanical responses were measured by attaching rosettes to the bone surface of the mandible to validate the FEM predictions. The relationship between real and predicted values indicates that the stress patterns calculated using FEM are a valid predictor of the biomechanics of the BTDO procedures. The present study provides an interesting correlation between the stiffness of the device and the biomechanical response of the mandible affected for bone transport. Copyright © 2014 by ASME.
Bone regeneration and docking site healing after bone transport distraction osteogenesis in the canine mandible
(W.B. Saunders Ltd, 2012-01-01) Nagashima, L.K.; Rondon-Newby, M.; Zakhary, I.E.; Nagy, W.W.; Zapata, U.; Dechow, P.C.; Opperman, L.A.; Elsalanty, M.E.; Universidad EAFIT. Departamento de Ingeniería Mecánica; Bioingeniería GIB (CES – EAFIT)
Purpose: Bone transport distraction osteogenesis provides a promising alternative to traditional grafting techniques. However, existing bone transport distraction osteogenesis devices have many limitations. The purpose of this research was to test a new device, the mandibular bone transport reconstruction plate, in an animal model with comparable mandible size to humans and to histologically and mechanically examine the regenerate bone. Materials and Methods: Eleven adult foxhounds were divided into an unreconstructed control group of 5 animals and an experimental group of 6 animals. In each animal, a 34-mm segmental defect was created in the mandible. The defect was reconstructed with a bone transport reconstruction plate. Histologic and biomechanical characteristics of the regenerate and unrepaired defect were analyzed and compared with bone on the contralateral side of the mandible after 4 weeks of consolidation. Results: The reconstructed defect was bridged with new bone, with little bone in the control defect. Regenerate density and microhardness were 22.3% and 42.6%, respectively, lower than the contralateral normal bone. Likewise, the anisotropy of the experimental group was statistically lower than in the contralateral bone. Half the experimental animals showed nonunion at the docking site. Conclusion: The device was very stable and easy to install and activate. After 1 month of consolidation, the defect was bridged with new bone, with evidence of active bone formation. Regenerate bone was less mature than the control bone. Studies are underway to identify when the regenerate properties compare with normal bone and to identify methods to augment bone union at the docking site. © 2012 American Association of Oral and Maxillofacial Surgeons.
Calidad de vida en pacientes con cardiopatía isquémica
(2015-12-18) Lemos, Mariantonia; Universidad EAFIT. Departamento de Ingeniería Mecánica; Bioingeniería GIB (CES – EAFIT)
La cardiopatía isquémica es una enfermedad crónica que lleva a cambios en el estilo de vida y en el funcionamiento físico de aquellos que la presentan.El presente artículo hace una revisión teórica de este tema, centrándose en la trayectoria que pres
Changes in illness perceptions after cognitive behavior therapy in depressed cardiac patients
(Springer New York LLC, 2015-04-01) Lemos, Mariantonia; Universidad EAFIT. Departamento de Ingeniería Mecánica; Bioingeniería GIB (CES – EAFIT)
Comparación de la aplicación del índice PAR en modelos e intraoralmente
(Facultad de Odontología, Universidad CES., 2004-01-01) Roldan, Samuel Ignacio; Universidad EAFIT. Departamento de Ingeniería Mecánica; Bioingeniería GIB (CES – EAFIT)
Comportamiento de las fuerzas generadas por un perno colado sobre una raíz por medio un análisis tridimensional de elementos finitos
(Facultad de Odontología, Universidad CES., 2004-01-01) Zapata, Abraham Uriel; Universidad EAFIT. Departamento de Ingeniería Mecánica; Bioingeniería GIB (CES – EAFIT)
Consideraciones sobre la depresión como factor de riesgo en pacientes cardiovasculares
(UNIV COMPROMETIDOS EXCELENCIA, 2015-01-01) Lemos, Mariantonia; Universidad EAFIT. Departamento de Ingeniería Mecánica; Bioingeniería GIB (CES – EAFIT)
Considerations of depression as risk factor in cardiovascular patients
(UNIV COMPROMETIDOS EXCELENCIA, 2015-01-01) Lemos, Mariantonia; Agudelo Velez, Diana Maria; Universidad EAFIT. Departamento de Ingeniería Mecánica; Bioingeniería GIB (CES – EAFIT)
Studies have found a strong association between depressive symptoms and major depression and cardiac morbidity and mortality increased after acute coronary syndrome (ACS); however it has also been reported evidence against this association. This difference in results may explain why depression has not yet been accepted by the American Heart Association as a risk factor for poor prognosis in patients with CVD. In this article depression is discussed as a risk factor of poor prognosis in patients who have had ACS and the factors that may influence the divergence of results in the studies. Our conclusions show that depression is related with a worse prognosis in ACS patients specifically when the symptomatology occurred after the event or when it is a treatment-resistant disorder. Cognitive and somatic symptoms and also comorbid anxiety are bad prognosis indicators.

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