Congenital malformations, systemic disease processes, and trauma can all result in alteration of the nasal structural framework, causing functional nasal obstruction and altered facial cosmoses. Current methods for nasal reconstruction include autogenous cartilage and bone grafts, synthetic alloplastic materials and demeneralized bone (Lindsy et al., 1996).
In modern time's autologous grafts for the nasal dorsum won general acceptance. Among them the primary choices are septal, conchal, and rib cartilage, each of them has its disadvantages. Septal cartilage is frequently defective or missing in secondary or post-traumatic nose and the obtainable volume may be insufficient (Romo et al., 1998).
Autogenous conchal cartilage is a preferred grafting material in the nasal reconstruction, however as with septal cartilage, this donor site may have been utilized in prior rhinoplastic surgery and its usefulness for straight dorsal onlay graft is limited, occasionally patients refuse to use auricular cartilage because of the presumed postoperative deformity of the donor site. Additionally conchal cartilage in the older patient can become flaccid or brittle and therefore is not a suitable support graft for nasal reconstruction. (Jovanovich and Berghaus, 1991).
Alloplastic grafts have also been used in the nasal dorsum. Soft Silastic, Gore Tex, Proplast and Coralline hydroxyapatite grafts have sometimes yielded satisfactory long term results (Owsley and Taylor, 1994). Mersilene has the advantage of inciting prolific fibrous in-growth, but the stability comes at the price of extreme difficulty in removing these implants should they become infected. Mersilene did not gain widespread acceptance among plastic and reconstructive surgeons as a nasal implant material. The use of Mersilene was supported based on properties such as relative ease of use, ability to tolerate Folding, ability to be sutured in place, and relative early stability. Infection rates as high as 4% have been noted necessitating removal in 2% of patients. As a polyester mesh, Mersilene does not undergo hydrolytic degradation when implanted (Colton, 1992).
Silicone in a various state of viscosity was popular alloplast. The body is unable to infiltrate the material and tends to establish a fibrous tissue capsule around the implant. Potential disadvantage include extrusion, infection, migration, and asymmetry (Nakakita et al., 1999).
Chitin exists in the exoskeleton of crustaceans, such as insects, crabs and shrimps and in the cell wall of the bacillus (Giraudguille MM, 1984). It is known that Chitosan, obtained by the alkaline deacetylation of chitin in industrial processing (Borzacchiiello et al., 2001) possesses excellent biological properties for accelerating wound healing (Ueno et al., 2001).
Furthermore, the biodegradation of Chitosan through hydrolytic enzymes (mainly lysozyme) can release aminosugars that are incorporated into glycosaminoglycans and glycoproteins, in addition as a biocompatible (Muzzarelli RA, 1995). (Chatelet et al., 2001) and bioactive polymer stimulates the immune system of the host against viral and bacterial infections by activating macrophages. These bioactive characteristics have led to its application as a regeneration material for hard and soft tissues, and as an absorbable suture (Vasudev et al.,1997) with many uses, such as in films, sponges, fibers, solutions, powders, flakes and gels.
In dentistry, chitin and its derivatives have also been applied as a dressing for oral mucosal wounds and as a tampon following radical treatment of maxillary sinusitis (Muzzarelli et al., 1993).
In addition, the use of chitin decreased the clinical symptoms and signs, coinciding with a reduction of the lysozyme concentration in the periapical regions over time through the use of intracanal medication (Ikeda et al., 2000).
Chitosan's properties allow it to rapidly clot blood, and have recently gained approval in the USA for use in bandages and other haemostatic agents. Chitosan is hypoallergenic, and has natural anti-bacterial properties, further supporting its use in field bandages (Kevin, 2006).
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