This article reports on a patient who required a cranial protection system. Using additive manufacturing techniques and surgical planning with the help of bio-models, a patient-specific bone implant solution was proposed that allows aesthetic restoration of the affected area and provides an adequate level of protection. In addition, through a comparative analysis with finite elements, the mechanical response to external actions of the medical device, printed with two materials: polymethylmethacrylate (PMMA) and polyether-ether-ketone (PEEK), is simulated. The tested materials have recognized biocompatibility properties, but their costs on the market differ significantly. The results obtained demonstrate the similarities in the responses of both materials. It offers the possibility that low-income people can access these devices, guaranteeing adequate biomechanical safety, considering that PMMA is a much cheaper material than PEEK.

New developments in terms of additive manufacturing, computational tools and mathematical simulation techniques have favored the development of successful methodologies for the restoration or restitution of bone structures in the human body. Likewise, achievements in Materials Science have allowed the development of biocompatible composites capable of achieving mechanical characteristics and biological similarities comparable to those of natural bone. Without considering the advantages and disadvantages of some biomaterials with respect to others, this research aims to evaluate the surgical planning, the design process, the impact resistance and the critical deflection of a customized cranial implant manufactured from polymethylmethacrylate (PMMA). With the support of finite element methods (FEM), the level of neurocranial protection offered by the implant is assessed.

In the present investigation, the mechanical properties of natural polyether-ether-ketone (PEEK), processed by additive manufacturing applying fused deposition modeling (FDM) with three different infill densities, are investigated. Mechanical characterization was performed through destructive testing. Specimens were designed in CAD software and printed with controlled infill densities of $40\%$, $70\%$, and $100\%$, using a rectilinear pattern. The results showed that increased infill density improves mechanical strength and stiffness but reduces ductility and energy absorption capacity. For considered infill densities, maximum stress levels reach values of $107.53\pm 6.29$MPa, $114.32\pm 11.95$MPa, and $63.96\pm 2.39$MPa, respectively, against compression, bending, and tensile loading. These findings offer crucial information for optimizing infill density in manufacturing high-strength components for industrial and biomedical applications. As a result, practical guidelines are provided for the design of medical devices, such as implants, achieving an appropriate balance between mechanical performance and material efficiency.

Mineral processing has been identified among the twelve main industrial processes that must be under control due to the expose to natural radioactive sources. The modification and, generally, the increase in the concentration of Naturally Occurring Radioactive Materials (NORM) in the earth's crust cause an imbalance in the ecosystem. Imbalance that affects the fauna, which are able to bio accumulate these radioisotopes and introduce them into the trophic chain. The main purpose of this work was to establish a radio-ecological baseline. For this purpose, the concentration levels of 226Ra in rainbow trout, in macro invertebrate matrices-substrates and water from the Irquis and Portete rivers were evaluated. A study area adjacent to the Loma Larga mining concession was selected. The measurements were made using the Lucas cells coupled to a Pylon AB6A counter and the "Can Technique", using LR-115 passive detectors. The results indicated that rainbow trout bio accumulated in bones and organsa mean of 94.7% of the total 226Ra detected, which values varied from 4.69 to 2.46 Bq/kg, while macro invertebrate-substrate matrices showed a concentration that ranged between 0.7 and 1.3 Bq/kg in the Irquis River, while in the Portete River was between 1.1 and 19.3 Bq/kg. The water samples, in the sampling points of the Irquis River, showed concentrations that ranged between 37.3 and 119.1 mBq/l and in the Portete River between 43.5 to 146.4 mBq/l.