Biologic Mesh: Classification and Evidence-Based Critical Appraisal

Numerous biologic meshes exist for soft tissue repair applications such as hernia repair/abdominal wall reconstruction. These materials can be classified based on the species and type of tissue from which they are derived, as well as the processing that the tissue undergoes. The impact of these variables on the mechanical properties and remodeling characteristics of biologic meshes are not well understood. Recent studies have documented the baseline physical, mechanical, and thermal properties of several biologic meshes, along with in vitro studies of the impact of repetitive loading and enzyme exposure on baseline mechanical properties. Porcine models have also described the mechanical strength and host tissue response of several biologic meshes in an in vivo setting. Additionally, a recent clinical trial has documented the remodeling characteristics of several types of biologic meshes after implantation in human subjects. The results of these studies have consistently shown that the effects of crosslinking are species/tissue dependent or related to the specific chemical compounds utilized to achieve crosslinking and the number of additional bonds ultimately introduced into these tissues. Additionally, differences have been observed between non-crosslinked materials, suggesting that widespread generalizations should not be made even amongst non-crosslinked materials. Differences due to species, tissue type, and other processing conditions such as decellularization and sterilization are likely as influential as the presence or absence of intentional crosslinking and should be explored further in future studies.