# Assessment of physicochemical alterations in 3D-printed biodegradable implants under biomimetic conditions for cranial defect repair

## TL;DR

This study evaluates how biodegradable cranial implants change under simulated body conditions, showing a significant loss in strength and mass over time.

## Contribution

The study introduces a novel simulated cranial defect physiological condition (SCDPC) to accurately predict biodegradable implant performance in vivo.

## Key findings

- BCP showed a 0.79% mass reduction and 69.30% decrease in tensile strength after 24 weeks in SCDPC.
- Molecular weight decreased by 9.67% in rabbits and 4.73% in SCDPC after 12 weeks.
- Physicochemical changes in vitro closely matched those observed in vivo.

## Abstract

Once implanted, biodegradable devices gradually deteriorate, potentially compromising clinical performance. Consequently, evaluating the alterations in physicochemical characteristics after implantation is crucial. Nonetheless, there is currently no established methodology for precisely assessing these alterations. This study sought to develop accurately simulated cranial defect physiological conditions (SCDPC) and examine the physicochemical modifications in biodegradable cranioplasty plates (BCP) to anticipate their performance changes following implantation in humans. We analyzed the physicochemical property alterations of BCP following 24 weeks of exposure to SCDPC. Following 24 weeks under SCDPC, the BCP showed a notable reduction in mass (− 0.79%) and tensile strength (− 69.30%). A decrease in molecular weight was noted after 12 weeks of implantation in rabbits (− 9.67%) and following 12 weeks of exposure to SCDPC (− 4.73%). The physicochemical alterations identified under simulated in vitro cranial defect conditions closely mirrored those found in the in vivo setting. In summary, assessing BCP under SCDPC offers an innovative and dependable approach for precisely forecasting performance shifts after implantation. This strategy could provide meaningful guidance for the advancement of BCP and various other biodegradable medical devices.