Oculopalpebral prosthesis prototype design using the additive manufacturing technique: A case study.

Three-dimensional (3D) printing technology has advanced for applications in the field of reconstructive surgery. This study reports the application of a comprehensive methodology to obtain an anatomical model, using computed tomography and 3D printing, to treat a patient with cancer who designed a prototype oculopalpebral prosthesis for the reconstruction of the affected area of the face (left eye). A personalized prototype was obtained, which adapted to the face of the person, and improved the aesthetics and quality of life. The applied techniques helped to make definitive prostheses using materials that could be permanent. The training and tests carried out in this study favored the understanding and assimilation of the technology and the possibility of applying it to patients in need of facial prosthetic rehabilitation.

Finite element analysis of a customized implant in PMMA coupled with the cranial bone.

This computational study investigates the effect of the Von Misses stresses and deformations distribution generated by coupling a customized cranial implant with its fixation system for anchoring in the cranial bone of a specific patient. Three simulations were carried out under static loads, in different areas of the implant and during the rest-activity; and another three simulations were considered preset maximum intracranial pressures. Anatomical models were obtained by computed tomography. The design of the device to be implanted was carried out by applying reverse engineering processes, from the corresponding computer-aided design (CAD) model of the bone structure of interest. Likewise, the anchoring system was modeled in detail. Loads were applied at three points on the custom implant. The stress distribution on the artificial plate and the implant-natural bone interface was analyzed. The distribution of the stresses caused by the internal load states on the plate and the anchoring system was also studied. The neurocranial reconstruction with the customized polymethylmethacrylate (PMMA)-based implant and the finite element analysis demonstrated that the fixation and coupling system of the bone-implant interface guarantees adequate protection for the internal structures of the restored area. In addition, the custom-designed and placed implant will not cause non-physiological harm to the patient. Nor will failures occur in the anchoring system.

Medición ecográfica del grosor del cartílago femoral en rodilla de jóvenes universitarios sanos / Ultrasound measurement of femoral cartilage thickness in the knee of healthy young university students

ANTECEDENTES Y OBJETIVO: El cartílago articular (CA) siempre está afectado en cualquier articulación con artrosis (A). La ecografía puede ser una herramienta útil en la monitorización de los cambios en el CA. El propósito del presente estudio es medir ecográficamente el grosor del CA en el fémur distal en jóvenes estudiantes y determinar su relación con el índice de masa corporal (IMC), masa muscular, grasa corporal y la práctica deportiva. MATERIALES Y MÉTODOS: Se realizó un estudio transversal observacional con voluntarios sanos, entre 15 y 25 años. Se recogieron datos antropométricos y se midió el grosor del cartílago femoral de la rodilla en cinco puntos. Además, se midió en un subgrupo el porcentaje de músculo y de grasa corporal. RESULTADOS: En el estudio se incluyeron 100 sujetos. La edad promedio fue de 20 años (± 2,5). El IMC promedio fue 23 kg/m2 (± 3,1). El CA tuvo un mayor grosor en los hombres y en los deportistas vs. las mujeres y los sedentarios, con diferencia estadísticamente significativa. Al comparar el IMC con el grosor del CA no se encontró ninguna relación significativa; sin embargo, sólo dos participantes tenían IMC > 30. CONCLUSIONES: El grosor del cartílago tiene una relación directamente proporcional con el porcentaje de músculo, e inversamente proporcional con el porcentaje de grasa. El IMC no es un buen parámetro al evaluar el comportamiento dinámico del cartílago en jóvenes no obesos

BACKGROUND AND OBJECTIVE: Articular cartilage (AC) is always affected in any joint with osteoarthritis. Ultrasound can be a useful tool in monitoring changes in the AC. The purpose of the present study is to ultrasound measure the thickness of the AC in the distal femur in young students and determine its relationship with body mass index (BMI), muscle mass, body fat and sports practice. MATERIALS AND METHODS: An observational cross-sectional study was conducted with healthy volunteers, between 15 and 25 years old. Anthropometric data were collected and the thickness of the femoral cartilage of the knee was measured at 5 points. In addition, the percentage of muscle and body fat was measured in a subgroup. RESULTS: 100 subjects were included in the study. The average age was 20 years (± 2.5). The average BMI was 23 kg/m2 (± 3.1). AC was thicker in men and sportsmen, versus women and sedentary people, with a statistically significant difference. When comparing BMI with AC thickness no significant relationship was found; however, only 2 participants had BMI > 30. CONCLUSIONS: Cartilage thickness has a direct relationship with the percentage of muscle, and inversely with the percentage of fat. BMI is not a good parameter when evaluating the dynamic behaviour of cartilage in non-obese youths

Ultrasound measurement of femoral cartilage thickness in the knee of healthy young university students. / Medición ecográfica del grosor del cartílago femoral en rodilla de jóvenes universitarios sanos.

BACKGROUND AND OBJECTIVE: Articular cartilage (AC) is always affected in any joint with osteoarthritis. Ultrasound can be a useful tool in monitoring changes in the AC. The purpose of the present study is to ultrasound measure the thickness of the AC in the distal femur in young students and determine its relationship with body mass index (BMI), muscle mass, body fat and sports practice. MATERIALS AND METHODS: An observational cross-sectional study was conducted with healthy volunteers, between 15 and 25 years old. Anthropometric data were collected and the thickness of the femoral cartilage of the knee was measured at 5 points. In addition, the percentage of muscle and body fat was measured in a subgroup. RESULTS: 100 subjects were included in the study. The average age was 20 years (± 2.5). The average BMI was 23 kg/m2 (± 3.1). AC was thicker in men and sportsmen, versus women and sedentary people, with a statistically significant difference. When comparing BMI with AC thickness no significant relationship was found; however, only 2 participants had BMI > 30. CONCLUSIONS: Cartilage thickness has a direct relationship with the percentage of muscle, and inversely with the percentage of fat. BMI is not a good parameter when evaluating the dynamic behaviour of cartilage in non-obese youths.

Association of human beta-defensin 1 gene polymorphisms with nonsegmental vitiligo.

BACKGROUND: Vitiligo is a pigmentation disorder of autoimmune aetiology. Polymorphisms in beta-defensin genes have been linked to a predisposition to some autoimmune disorders. AIM: To evaluate the role of polymorphisms in DEFB1, the gene encoding for human beta-defensin (HBD)-1 and its 5' untranslated region in nonsegmental vitiligo. METHODS: In total, 354 participants [171 patients with non-segmental vitiligo and 183 age and sex-matched healthy controls (HCs)], were genotyped by the PCR-restriction fragment length polymorphism (RFLP) method. For 80 of these individuals (40 patients and -40 HCs) serum HBD-1 was also measured by ELISA. RESULTS: The -44 G allele, CG genotype and GGG haplotype increased the risk for vitiligo (P < 0.02 in all cases), whereas the -20 AA genotype seems to be protective (P = 0.04). Serum HBD-1 levels were lower in patients with vitiligo than in HCs (P < 0.01), as well as in patients with active vitiligo compared with those with stable vitiligo and with HCs (P < 0.05 in both cases), CONCLUSION: Our results suggest that HBD-1 and its gene polymorphisms may modulate vitiligo susceptibility and/or disease activity. This is the first report, to our knowledge, of the association of serum HBD-1 levels and DEFB1 gene polymorphisms with vitiligo.