The use of adhesives in medical applications was for a long time restricted to the production of self-adhesive bandages (plasters, self-adhesive strips of fabric, etc.). The first force sensitive adhesives used for this were based on natural rubber. This was in part later outmoded by synthetic rubbers (e.g. polyisoprene, polyisobutylene). In the center of the 20th century, pressure sensitive adhesives based on polyacrylic acid esters became increasingly important, both for general use and for dressing materials.

 

Adhesives are today employed in diverse areas of medicine, replacing traditional methods with “friendlier” processes. In many cases, for example, stitches can be avoided by applying special cyanoacrylate adhesives to quickly close skin wounds. An advantage here is that the complete wound can be covered, so mostly suppressing secondary bleeding and the danger of infection. Cyanoacrylic acid butyl ester is normally preferred over the methyl and ethyl esters because it cures other slowly and the polymerisation produces less heat; it also causes less tissue irritation. By and huge, this adhesive is only used for relatively small wounds and occasionally in vascular surgery.   

Think about the transdermal patch…where the medicine delivery method to the blood stream is through the skin. Glues allow a more proficient technique of drug delivery rather than prescribing a high-ingestion dosage (which is subsequently flushed out of the body by the liver). Transdermal patch technology is highly successful as the adhesive that sticks the patch to your skin - made of products of chemistry like acrylic, acrylic-rubber hybrid, and styrenic rubber solution - in fact controls the rate at which the drug enters the body. This ensures that the drug dose is continuously and evenly administered all through the day, with no the spikes and falls linked with medicines taken orally.

 

 

The uses are numerous…smoke cessation, hormone replacement, and cardiovascular aid (I.e. nitroglycerin delivery) are commonplace. New transdermal patches hit the market every day with additional items like pain cessation becoming a reality. Other innovative products such as foot care and cosmetic patches, and nasal dilator strips have hit the market in recent years all possible because of the matchless functional characteristics of the pressure sensitive adhesives integral to the product.

 

 One of the latest bioadhesives on the market enables drugs to be delivered through the inside of the oral cavity, nasal passages and other mucus membranes as an alternative of just through skin. It adheres really well to the soft, damp mucus membranes of the body because of adhesives made from starch-polyacrylic acid blends, which then completely wear down and disappear. Drug makers are able to put their drug into tablet, film or powder form, and the patient is able to attach the product directly to a mucus membrane, providing a way for controlled delivery of drugs to specific areas of the body or systemically.

 

 

In cardiovascular surgical procedure, fibrin, a soluble protein recovered from blood, is a crucial sealing agent having a haemostatic effect. Compared to cyanoacrylates, fibrin is gentler to body tissue except prior to use it must undergo a special treatment to stop germs being spread. The use of methacrylate based adhesives has been a huge success in orthopaedics for anchoring hip socket implants to the bone. There are currently no other types of adhesive used for this application. The adhesive products comprise a.) a powder component and b.) a liquid component (whose main components are methyl methacrylate and a polymerisation accelerator). Although this type of adhesive puts a not inconsiderable stress on bone and tissue due to the strong heat development, hip and knee implants anchored by means of this adhesive are in 90 percent of cases functional for about 15 years.

 

 

In field of dentistry, fillings based on UV curing acrylates have largely replaced conventional filling materials such as amalgam. The products have a long open time (the period during which they can be used after mixing) and bond in just a minute or so when exposed to UV light.