Investigation of the expansion properties of osmotic expanders with and without silicone shell in animals.

Background: Particularly in clinical studies, it has been found that rapid swelling of tissue expanders leads to high-pressure peaks that can cause hypoxia in the tissue and thus also skin damage. For this reason, the present study in animals investigated whether an osmotic expander with silicone shell is capable of expanding in tissue and bringing about useful tissue expansion without complications. It was also examined whether and what quantitative and qualitative differences there are between conventional osmotic expanders and the new expanders with silicone shell.

Methods: The expansion of osmotic expanders with silicone shell was compared with that of osmotic expanders without silicone shell in four mini pigs. The expander type used was an M1 rectangle with an initial volume of 6 ml. Five expanders were implanted in each pig, meaning that 20 expanders were measured. The volume of the expanders was measured directly after explantation. Indirect volume determination was performed by producing plaster casts for subsequent laser optical measurement.

Results: Comparison of the two curve profiles showed a much flatter profile for the expanders with silicone shell. The absolute values for the volumes of the expanders with silicone shell were likewise substantially lower.

Conclusions: Controlled skin expansion is a technique of providing localized donor tissue for reconstructive surgery. The new expanders could be in a position to lower the rate of complications in tissue expansion.