Department of Plastic Surgery, University of Szeged, Szeged, Hungary.
Skin Pharmacol Physiol. 2009;22(6):305-12. doi: 10.1159/000241300. Epub 2009 Sep 25.
Osmotically active tissue expanders allow the harvesting of soft tissue for reconstruction after different injuries. However, their expansion properties could be improved. Thus, our goal was to examine the in vivo applicability of acrylamide (AAm), acrylic acid (AAc) and N- isopropylacrylamide (NIPAAm) hydrogels.
Cylinders of AAm, AAc and NIPAAm hydrogels were implanted under the skin of rats in the dorsal region. The diameter and the length of the cylinders were measured daily. After removal of the hydrogels, their mass and rheological properties were determined. Further, biopsies were taken from the adjacent tissue for histological analysis.
The hydrogels reached the peak of swelling by the end of the 2nd postoperative week. The wet mass of the removed cylinders was 25 times their dry mass prior to implantation. NIPAAm polymers exhibited the most favourable visco-elastic properties, with the highest tendency to retain their preformed shape. The histological analysis revealed serious tissue damage when the AAc devices were used, whereas the AAm and NIPAAm did not result in such lesions.
In view of its mechanical and biological properties, NIPAAm hydrogel seems to be the most appropriate of these materials for application in plastic and reconstructive surgery.
渗透压活性组织扩张器可用于在不同损伤后采集软组织进行重建。然而，其扩张性能可以得到改善。因此，我们的目标是研究丙烯酰胺（AAm）、丙烯酸（AAc）和 N-异丙基丙烯酰胺（NIPAAm）水凝胶的体内适用性。
将 AAm、AAc 和 NIPAAm 水凝胶圆柱体植入大鼠背部皮肤下。每天测量圆柱体的直径和长度。取出水凝胶后，测定其质量和流变性能。此外，从相邻组织中取出活检进行组织学分析。
水凝胶在术后第 2 周末达到肿胀的峰值。取出的圆柱体的湿重是植入前干重的 25 倍。NIPAAm 聚合物表现出最有利的粘弹性，具有保持其预先形成形状的最高趋势。组织学分析显示，当使用 AAc 装置时会导致严重的组织损伤，而 AAm 和 NIPAAm 则不会导致这种损伤。
鉴于其机械和生物学特性，NIPAAm 水凝胶似乎是这些材料中最适合应用于整形和重建外科的材料。
