[Titanium-coated silicone is not effective for preventing graft infection]

Titanium-coated grafts for breast augmentation are available since 2001 and are used clinically. The titan surface is supposed to improve the tissue compatibility and to lower the infection rate. It was the aim of the present study to validate the antibacterial efficiency of titanium-coated silicone.

C3H/HcN mice were assigned to four different groups (n=6/group). Silicone without (group I and III) or with (group II and IV) titanium were implanted subcutaneously. Following this in groups III and IV a local contamination was induced with 2 x 10 (7) CFU/0.1 ml Staphylococcus aureus ATCC 25923. Groups I and II were not infected. 14 days after primary operation all animals were euthanized and the grafts harvested. Specimens were examined for signs of infections by macroscopy, histology and microbiology.

In group I none of the grafts were infected (0/5). In group II (silicone, + titanium, no contamination) one infection was evident due to biting of the animal (1/6). In group III (silicone, no titanium, contamination) an infection was detected in all mice (6/6). The use of titanium, however, did not significantly reduce the infection rate in contaminated animals (group IV, 5/6). Interestingly, tissue integration of titanium-coated grafts was macroscopically reduced compared to non- titanium-coated grafts (group II vs. I).

The titanium-coated silicone grafts were not effective in protecting infection in vivo. The decreased tissue integration of titanium-coated grafts, however, might reduce the rate of capsular contracture. This potential advantage of titanium needs to be validated in controlled clinical trials.