[Biomechanical properties of skin expanded by different methods in vivo]

In plastic surgery, people hope the conventional expansion will be replaced by rapid expansion, which can shorten greatly the expansion period. Also people are concerned about whether the skin properties after rapid expansion approach that after conventional expansion. So we designed and made an apparatus for in vivo measurement of tension, and then measured the biomechanical properties of skin in vivo for the first time. The experimental results showed there was no significant difference between the rapid expansion method and conventional expansion method in respect to the area gain of expanded skin surface. Both the tension in vivo and the instant stretch-back ratio increased during the expansion, but fell almost to the control values after four weeks' maintaining period. So, rapid skin expansion did not produce any deleterious effect when compared with the conventional expansion. Extension of the maintaining period can improve the biomechanical properties of expanded skin and effectively reduce the stretch-back ratio. Therefore, rapid expansion with an extended maintaining period is clinically acceptable.