All attached. Shape memory sutures node when exposed to heat.
Surgeons could soon seal wounds difficult to reach using new son to change shape who know how to bind and never needs to be removed. The new biodegradable plastic fiber "smart" can be forged when heated to a few degrees above body temperature. The researchers say that the same material could be made to last much longer and one day be used for medical self-healing devices and shrink otherwise bulky implants -. Such as screws that hold the bones together
A growing class of materials have "shape memory" - they hold a form at a certain temperature and transform into another shape when heated. So far, none of these plastics have been used in medical devices, nor had any found to be biodegradable. The new material, described online April 25 in Science by the synthetic chemist Andreas Lendlein of mnemoScience GmbH in Aachen, Germany, and biomedical engineer Robert Langer of the Massachusetts Institute of Technology, is composed of two polymers, each already used separately in clinical applications such as drug delivery.
When combined, the two polymers react to temperature. The highest temperature form is "permanent" in the form of the plastic, which assumes after heating. After it cools down, the plastic can be stretched or crumpled into temporary forms up to four times larger or smaller than the permanent form. To make sutures, the researchers took a fiber of their shape-changing material and, after warming up for several minutes, cooled down and stretched. They used the loose sewing thread a wound on a rat. When heated to 40 ° C, tight suture with just the right amount of tension, avoiding damage to the surrounding tissue.
Medical devices that can fit into tiny holes in the body and develop forms designed with the request would be valuable, said Frederick Finelli laparoscopic surgeon at Medical Center of George Washington University in Washington, DC But he warned that the surgeons may feel uncomfortable not having direct control over the changing form implants. "If the size is predetermined and that you have it and you preheated then it turns out it is too small, what do you do then? These are the things the surgeons are concerned."
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mnemoScience Gmbh
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