An Evaluation of the Bacterial Adherence to Casting Materials

Area of Science:

• Biomaterials Science
• Infectious Disease Control
• Orthopedic Materials

Background:

• Casting materials are prone to bacterial adherence, posing infection risks.
• Traditional materials like plaster and fiberglass have limitations in decontamination.
• Novel materials are needed to improve hygiene during patient immobilization.

Purpose of the Study:

• To evaluate bacterial adherence to various casting materials.
• To compare the decontamination efficacy of different casting materials.
• To assess the potential of silicone-coated 3D printed plastic as a hygienic casting solution.

Main Methods:

• Determined minimal inhibitory concentration of a phosphate-free detergent for bacterial kill-off.
• Inoculated plaster, fiberglass, 3D printed plastic, and silicone-coated 3D printed plastic with *Staphylococcus aureus*.
• Visualized bacterial adherence using scanning electron microscopy and quantified remaining bacteria via CFU counts after washing trials with sterile water or detergent.

Main Results:

• Silicone-coated 3D printed plastic exhibited significantly lower initial bacterial adherence (58,879 CFU) compared to plastic (217,479 CFU), plaster (140,063 CFU), and fiberglass (550,546 CFU).
• Silicone-coated 3D printed plastic showed superior decontamination, with only 9.3% remaining bacteria (1,797 CFU) after detergent washing, versus 19,321 CFU with sterile water.
• The mean remaining bacteria on silicone-coated 3D printed plastic were significantly lower than all other materials after washing with sterile water or detergent for both 1 and 3 minutes.

Conclusions:

• Silicone-coated 3D printed plastic demonstrates reduced bacterial adherence and enhanced decontamination capabilities.
• This material offers a more hygienic alternative to conventional casting materials for immobilized patients.
• The findings support the use of 3D printed casts for improved patient safety, especially during infectious crises like COVID-19.