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Preterm prelabor rupture of membranes (PPROM) is the most frequent complication of fetal surgery. Strategies to seal the membrane defect created by fetoscopy aiming to reduce the occurrence of PPROM have been attempted with little success. The objective of this study was to evaluate the ex-vivo mechanical sealing properties and toxicity of four different bioadhesives integrated in semi-rigid patches for fetal membranes. We performed and ex-vivo study using term human fetal membranes to compare the four integrated patches composed of silicone or silicone-polyurethane combined with dopaminated-hyaluronic acid or hydroxypropyl methylcellulose (HPMC). For mechanical sealing properties, membranes were mounted in a multiaxial inflation device with saline, perforated and sealed with the 4 combinations. We measured bursting pressure and maximum pressure free of leakage (n = 8). For toxicity, an organ culture of membranes sealed with the patches was used to measure pyknotic index (PI) and lactate dehydrogenase (LDH) concentration (n = 5). All bioadhesives achieved appropriate bursting pressures, but only HPMC forms achieved high maximum pressures free of leakage. Concerning toxicity, bioadhesives showed low PI and LDH levels, suggesting no cell toxicity. We conclude that a semi-rigid patch coated with HPMC achieved ex-vivo sealing of iatrogenic defects in fetal membranes with no signs of cell toxicity. These results warrant further research addressing long-term adhesiveness and feasibility as a sealing system for fetoscopy.

Increasing life expectancy is leading to an increase inage-related diseases, like osteoporosis, which often involve the breakdown of bone. One of the main problems related with such disease is the formation of vertebral compression fractures (VCF). The impact of the vertebral compression fractures that have been describedis diverse, such as distortion in the spine (kyphosis), chronic back pain, reduced physical function with risk of immobility, decline of lung function, gastroesophagealreflux and change in appearance that may led tosocial isolation, loss of self-esteem and depression. Vertebral fracture is just the beginning of the constant deterioration of the health of the affected patients. Until now, the treatments applied in this type of fracture are mainly three: conservative medicaltreatment, invasive surgical intervention, and vertebroplasty and kyphoplasty. These last two techniques,minimally invasive, have shown interesting resultsthough there is still room for improvement, especially due to the lack of an ideal bone cement material. In this review, we will focus on the recent developments in vertebroplasty, their pros and cons and the needs for further achievements. We therefore begin with a brief description of vertebroplasty followed with a description of the biomechanical and the osteoregeneration needs that materials should ful fill to be useful in this application. Finally, we describe the recent materials developments for vertebroplasty and the different proposals for improvement.

Plastic Laminated Object Manufacturing has not been assessed from the flexural properties point of view. The deflection range in parts manufactured by this technique is wider than in parts fabricated by other additive manufacturing methods like SLS or FDM. This fact has increased the interest on the final application of these parts rather than restricted to Rapid Prototyping applications. In this study it will be compared the impact of building orientation and geometric features of parts over the flexural properties. Through optical observation it will be studied the failure mechanism.