Compression mechanical properties of porous polylactic acid scaffolds generated by 3 D printing and sterilized with autoclave; Propiedades mecánicas a la compresión de matrices porosas de ácido poliláctico generadas con impresión 3 D y esterilizadas con autoclave

Autores de IIS La Fe

• Lucia Cucó Sanz

  Autor

• 

  María Ángeles Tormo Mas

  Autor

• José Baeza Oliete

  Autor

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  Francisco Baixauli García

  Autor

• Javier Pemán García

  Autor

Grupos

• Cirugía Ortopédica y Traumatología

• Infección Grave

Abstract

Introduction and objectives: Three-dimensional (3 D) printing and polylactic acid (PLA) have attacted considerable interest in the medical field thanks to their versatility. 3 D printers can reproduce the microarchitecture of the designed objects and PLA has mechanical properties similar to bone. This makes the technology highly promising for personalized treatment of bone defects. In this article explores the changes to the designed object suffers after the printing, sterilization, and its behavior when subjected to compression forces before and after autoclave sterilization. Methods: PLA scaffolds with 3 different pore sizes were designed and 3D-printed. Half of these were autoclaved. Dimensions in all three axes were measured on sterilized and unsterilized sets of scaffolds. Then, their compressive mechanical properties were assessed in different orientations. Results: A decrease in the dimensions of the X and Y axes, as well as in the volumen, was observed in the sterilized scaffolds, while the dimensions in the Z axis increased compared to the non-sterilized ones. In the compression study, it was observed that in the non-sterilized scaffolds failed more elastically in the Z axis, with failure ocurring by accumulation of layers, but without abrupt drops in resistance. In contrast, sudden drops in load-bearing capability were observed in the sterilized scaffolds. In the X and Y axes, the scaffolds failed due to dissociation between layers. The collapse of the mechanical support was more pronounced in the sterilized scaffolds. Conclusions: According to the results of this study, 3 D printing enables the production of customized models that adhere closely to the design, with dimensional deviations of less than 1%. However, autoclave sterilization reduces the dimensions of the X and Y axes (-4.4%) and increases those of the Z axis (+5.1%). This results in a decrease in total volume (-4.2%), which is more noticeable in scaffolds with larger pores (-6.6%). These alterations should be taken into account when designing to compensate them. Despite being stiffened and weakened by the autoclave, PLA scaffolds withstand an average compression of 320 MPa, compared to 380 MPa for unsterilized scaffolds. In the future, alloys could improve the compressive strength of PLA. © 2025 SECOT

Copyright © 2025 SECOT. Publicado por Elsevier España, S.L.U. All rights reserved.

Keywords

• 3D printing; Mechanic compression; Polylactic acid; Porous scaffolds; Sterilization