In vitro comparative study of deformation of 3D-printed models using different polylactic acids treated by steam...

Area of Science:

• Biomaterials Engineering
• Orthopedic Surgery Innovations
• 3D Printing Technology

Background:

• 3D printing is increasingly used in orthopedic surgery, necessitating materials compatible with sterilization.
• Polylactic acid (PLA) is common but its thermosensitivity raises sterilization concerns.
• Directly sterilizable 3D-printed PLA parts offer significant advantages if deformation is managed.

Purpose of the Study:

• To evaluate the in vitro resistance of 3D-printed polylactic acid (PLA) parts to steam sterilization.
• To determine if PLA material type and printed object shape influence post-sterilization deformation.
• To assess the feasibility of using 3D-printed PLA in hospital settings requiring sterile components.

Main Methods:

• Four types of polylactic acid (PLA) were used to 3D print simple cubes and complex cuboid bone shapes.
• Printed parts were subjected to steam sterilization under standard French hospital conditions.
• Dimensional changes (deformation) were measured using a digital caliper before and after sterilization.

Main Results:

• Cuboid bone shapes made from HT-PLA and PLA-WANAO showed non-significant deformation (<0.5mm) after sterilization.
• PLA-SUNLU and PLA-G3D cuboid shapes exhibited significant deformation (-1.37mm and -35.03mm, respectively).
• All tested PLA types, including cubes and cuboid shapes, showed significant deformation, with cubes deforming more severely.

Conclusions:

• Specific polylactic acid (PLA) formulations can resist steam sterilization with minimal deformation (<1mm), particularly for complex shapes.
• The choice of PLA material is crucial for maintaining dimensional stability after sterilization.
• While promising for anatomical parts, further research and a legal framework are needed for safe clinical application of 3D-printed PLA in hospitals.