The implementation in the use of BP has greatly facilitated the complex hernia treatment. This kind of ventral hernia repair represents a significant challenge for surgeons. The complexity of hernias could derive from trauma, contamination/infection, tissue loss, dimensions, anatomic position, and clinical or pharmacological data (Figs. 19.2 and 19.3). BP have completely changed the way to face the hernia surgery. They introduced the tissue engineering in surgical practice. The implantation of a biologic material triggers a cascade of events leading to new healthy tissue deposition and prosthesis remodeling. It also allows blood, growth and pro-/anti-inflammatory factors, and drugs to reach the surgical field during the first phases of healing process. This for sure enhances the effect against potential or certain contamination/infection [25]. It has been demonstrated in animal models as the tensile strength is different between cross-linked and non-cross-linked meshes during the first months after the implant. However, it reaches similar values after 12 months with the two kinds of meshes. Moreover, the strength of the repair sites doesn’t change over time. This might indicate that new tissue is deposited in the repair site as the scaffold is degraded, preventing the site from weakening over time. Another factor that should be kept into account in choosing which kind of BP to use is the demonstration that non-cross-linked material exhibits more favorable remodeling characteristics. This has a great importance when BP are used as bridge to cover tissue loss. In fact, discordant data have been published about the use of BP to bridge wide defect. Few different nonrandomized studies have been published reporting recurrence rate ranging between 100 % and 0 % if the prosthesis are placed, respectively, either as a bridge or not. Even if high-quality comparative data about BP exists in animal models, only clinical reports of a restricted number of cases are reported for humans. No definitive evidence-based conclusions could be obtained from the literature. The majority of surgeons stated they use BP in “difficult” situations, especially those with contaminated or infected field [11].

The Italian Biological Prosthesis Work Group (IBPWG) proposed a decisional model in the use of BP to facilitate the choice between the different types of BP [25].

The aforementioned decisional model suggests that the decision about which prosthesis to utilize should always be a dynamic process mediated by the surgeon decisional capability. The principal variables to keep in mind in deciding the kind of BP to use are infection grade and loss of tissue size.

Infection has been divided into three possible grades:

The same three-step division has been adopted for the tissue loss:

By combining together these variables (multiplication), a score could be obtained which suggests the necessity to use either a cross-linked or a non-cross-linked BP (Figs. 19.4 and 19.5).