It is reported that foreign countries began to use braided sutures gradually in the 1960s. By the 1970s, the proportion of braided silk thread in medical silk thread had reached 70%. In the middle and late 1980s, braided silk thread has basically replaced twisted silk thread, accounting for nearly 65,438+000% of medical silk thread. Since the end of the 20th century, monofilament, knitting and twisting have coexisted in the domestic market, but the proportion of the first two is increasing year by year, especially the braided suture, which has developed rapidly although it has not developed for a long time. Medical silk thread woven suture is one of the best products widely used in medical surgery in the world, and it is also an upgraded product of medical silk thread. In recent years, the following medical sutures have appeared on the market.
1. Surgical suture
Suture is a sterile filament used to connect two biological tissues until they grow well, or to connect one tissue with a prosthesis. The suture can be monofilament, multi-strand, woven or non-woven fabric. The most important requirement for it is that human tissues can accept it. The Department of Textile Technology of Delhi Institute of Technology in India has been studying antibacterial and biocompatible textile materials and scaffold materials. Usually due to the lack of necessary maintenance after operation, there are many opportunities for suture wound infection. Antibacterial suture made of nylon and polypropylene monofilament is still in progress, and high-energy γ -ray irradiation and plasma irradiation are used to ensure that its mechanical properties and fastness are not affected. Some antibacterial drugs were coated on the surface of the suture, and slowly penetrated into the suture to prevent bacteria from invading. This suture has good biocompatibility and no side effects are found.
2. barb suture
Recently, there has been a two-way barbed seam method, which can stop knotting. Using this kind of thread can connect wound tissues together, without pulling and dragging, the wound is evenly stressed and the deformation is reduced. This sewing method is characterized by steep needle insertion and moderate depth, which is stronger than the general sewing method.
3. Gelatin coating line
The operability of gelatin coating line is excellent. Gelatin coating line can improve the surface smoothness and reduce the debris produced during sewing. The processing technology is as follows: the suture is soaked in gelatin aqueous solution, so that the surface of the suture is coated with this material, and a fixing agent and a crosslinking agent are added. The whole process is divided into several steps, that is, the coating line contacts the buffer solution, and then it is heated to 50℃ for a period of time, usually 1-20 hours. Sometimes a plasticizer is added to the gelatin solution, and the general plasticizer is triethyl citrate, glycerol or other polyols. Plasticizer is mainly used to improve the coating performance of gelatin, and the fixing solution used in the process is a crosslinking agent. The prefer crosslinking agent is dialdehyde, such as glyoxal, which can be use alone or mixed with formaldehyde or other acetaldehyde.
4. Catgut polymer mixed yarn
Catgut can be absorbed, but sometimes it will cause some uncomfortable reactions. This phenomenon can be avoided if catgut-polymer synthetic suture is used. This suture may gradually degrade under the action of enzymes. In order to avoid degradation, a protective polymer film can be coated on the surface of the material to shield the collagen of the enzyme from being decomposed by enzyme, but it can be degraded by water. This polymer is connected by urethane and urea to enhance its performance, which is very suitable for catgut. The specific method is to immerse catgut in this polymer solution and then quench it.