Biological tissue adhesives

There are different types of commercially available tissue adhesives, classified into three categories natural or biological, synthetic and semisynthetic, and biomimetic. The biological tissue adhesives such as fibrin glues and collagen are quite effective in select applications. Their drawbacks are high cost and limited availability. The action of biomimetic adhesives is based on... 

There are many obstacles to permanent adhesion under oral conditions. The substrate is a biological tissue and subject to change, and the presence of moisture represents the worst kind of situation for adhesion. Water is the great barrier to adhesion. It competes for the polar surface of tooth material against any potential polymer adhesive. It also tends to hydrolyse any adhesive bond formed. These twin obstacles gave rise to considerable doubt as to whether materials adhesive to tooth material could be developed at all (Cornell, 1961). 

To mimic the macromolecular-based ECM in biological tissue, the cell adhesion and proliferation properties of hydrogels are critical parameters. However, various hydrogels that originate from natural resources, such as alginate [87], chitosan [88, 89], and hyaluronic acid [90], and that are synthetically created, such as poly (7V-isopropylacrylamide) (PNIPAAm) [91], PEO [92], PVA [93], and poly(ethylene glycol) (PEG) [94], show a poor cellular viability without modification with cell adhesive proteins or peptides, such as collagen, laminin, fibronectin, and the RGD (Arg-Gly-Asp) sequence. 

One consequence of the swelling of hydrocolloids is that adhesion to substrates, in particular to biological tissues or mucosae, may occur. Advantage can be taken of this finding to retain a dosage form in a certain site where drug delivery or absorption is optimum. 

Cyanoacrylates have become very useful as tissue adhesives in surgical applications, because they polymerize rapidly in contact with moisture and create an extremely tenacious film. Methyl cyanoacrylate, used initially, has now fallen out of favor because of its toxic properties. The butyl and heptyl analogs are, however, quite satisfactory and do not produce objectionable tissue response. They also degrade at a much slower rate than the methyl compound in a biological environment. 

Some of the most interesting properties of PGA that make it an ideal material for biological applications are its molecular weight, viscosity, biodegradability, and most importantly its vast availability[237,240,244]. It has found profound applications in the areas of development of scaffolds, drug and gene delivery, and tissue adhesive and sealant and coatings for several applications. Some of the... 

Ferreira et al. [75] synthesized a HMA for medical use. Urethanes based on polycaprolactone diol (PCL) were synthesized by reaction of the molecule either with isophorone diisocyanate (IPD-isocyanate) or hexamethylene diisocyanate (HDI-isocyanate). Nies Berthold et al. [76] tried out an adhesive composition based on polymers or polymer blends consisting of caprolactone copolymers or caprolactone copolymers and polycaprolactone. The adhesive can be utilized as HMA for temporarily gluing together biological tissue and other materials in medicine. 

This chapter discusses the phenomenon of ceU adhesion both from a tissue perspective and from a biomaterial perspective. Section 34.2 describes the cell biology of adhesion receptors and then-relevance to particular tissue functions. Section 34.3 addresses cell adhesion to biomaterials with... 

---