Biomimetic and Nonbiomimetic Approaches in Dura Substitutes: The Influence of Mechanical Properties

Abstract

The dura mater, the furthest and strongest layer of the meninges, is crucial for protecting the brain and spinal cord. Its biomechanical behavior is vital, as any alterations can compromise biological functions. In recent decades, interest in the dura mater has increased due to the need for hermetic closure of dural defects prompting the development of several substitutes. Collagen-based dural substitutes are common commercial options, but they lack the complex biological and structural elements of the native dura mater, impacting regeneration and potentially causing complications like wound/postoperative infection and cerebrospinal fluid (CSF) leakage. To face this issue, recent tissue engineering approaches focus on creating biomimetic dura mater substitutes. The objective of this review is to discuss whether mimicking the mechanical properties of native tissue or ensuring high biocompatibility and bioactivity is more critical in developing effective dural substitutes, or if both aspects should be systematically linked. After a brief description of the properties and architecture of the native cranial dura, we describe the advantages and limitations of biomimetic dura mater substitutes to better understand their relevance. In particular, we consider biomechanical properties’ impact on dura repair’s effectiveness. Finally, the obstacles and perspectives for developing the ideal dural substitute are explored.

Impact Statement

Dura mater, a crucial protective membrane for the brain and spinal cord, often requires artificial substitutes when injured or removed. However, complications are still frequent (up to 40% of CSF leakage) because substitutes lack the biological complexity and structural factors of native tissue, which affects its complete regeneration and function. This review discusses whether mimicking the mechanical properties of native tissue or ensuring high biocompatibility and bioactivity is more critical in developing an effective dural substitute. Overall, it can be assumed that mimicking the multiphasic structure could be more important than mimicking accurate biomechanical properties to achieve proper healing.