Correlation between successful rate of skin-defect repair with tissue-engineered skin and methods of operation

Lisheng HE; Yan JIN; Tianzheng DENG; Shaohua SONG; Peng LIU; Sha HUANG

ABSTRACT

BACKGROUND:

Skin defect is commonly repaired by autologous skin graft, but in which, it is required healthy skin provider and it probably results in scarring deformity to various extents. The successful construction and clinical application of tissue-engineered skin (TE skin) mark the major breakthrough in treatment of skin defect.

OBJECTIVE:

To analyze the relationship between operation method and healing rate, through repair of skin defect with TE skin, to provide experimental evidence on clinical application of TE skin.

DESIGN:

Randomized controlled observation was designed.

SETTING:

Department of Oral and Maxillofacial Surgery, Teaching-Research Room of Histology and Pathology and Experimental Center of Tissue Engineering, School of Stomatology, Fourth Military Medical University of Chinese PLAMATERIALS The experiment was performed in Experimental Center of Tissue Engineering, School of Stomatology, Fourth Military Medical University, in which 6 healthy York pigs were employed, of clean grade,aged varied from 2.5 to 3 months. 3 groups were randomized, named TE whole-layer group, TE dermal and auto-epidermal group and auto-graft group, 2 pigs in each group. 8 wounds were prepared in each pig, round in shape and 50 mm in diameter, 16 wounds in each group, totally 48wounds.

METHODS:

①Preparation of TE whole layer and TE true skin. ② In TE whole-layer group The whole layer of skin was cut off from fat layeralong the drawn line. When bleeding stopped thoroughly and the wound was covered with wet physiological saline gauze, TE whole-layer skin was collected and windowing was done on the skin for drainage. Physiological saline was used to rinsed away the culture solution on the surface of TE skin, and then, the cuticular layer was upward-covered the wound, avoiding gas vacuole between cuticular layer and wound. Single-layer oleic gauze, physiological saline gauze, aseptic dry gauze and elastic sponge cushion were covered successively, about 3-5 mm in thickness each layer. After routine dressing, elastic bandage was wrapped with compression terminally. ③ TE dermal and auto-epidermal group The whole- layer skin was cut off with same method. Thin split-thickness skin (TIS) 0.1-0.2 mm was collected with drum dermanuring machine and soaked in physiological saline. The same method was used to collect the managed TE true skin and cover it on the wound, covering immediately on autoTTS. The rest management was same as TE whole-layer group. ④ Autograft group The whole-layer skin was cut off and the fat tissue was removed, afterwards, it was re-grafted on the auto-wound, covered with various layers of dressing and bandaged with compression. ⑤ The survival case was determined if it was discovered no infection, necrosis and scaling of grafted skin, less than 3 mm in diameter when the wound was opened for changing fresh dressing each time, otherwise, the failed case was recorded. The survival rate in each group was analyzed statistically in 4 weeks after operation.MAIN OUTCOME

MEASURES:

Survival situation of grafted skin in 4weeks after operation in each group.

RESULTS:

In 4 weeks after operation, the survival rate of grafted skin was 75% in TE whole-layer group was 87% in TE dermal and auto-epidermal group and was 94% in auto-graft group. The results were similar basically in comparison among 3 groups (x2=-2.34, P ＞ 0.05).

CONCLUSION:

The effect of TE skin graft on repair of skin defect is near to that of auto-epidermal graft, testifying that the repair of skin defect with TE skin is feasible.