**1. Introduction**

424 Biomaterials – Physics and Chemistry

Ghanaati S, Orth C, Unger RE,etc. Fine-tuning scaffolds for tissue regeneration: effects of

Mandal BB, Das T, Kundu SC. Non-bioengineered silk gland fibroin micromolded matrices to study cell-surface interactions. Biomed Microdevices. 2009 Apr;11(2):467-76. Acharya C, Ghosh SK, Kundu SC. Silk fibroin protein from mulberry and non-mulberry

Yang Y, Chen X, Ding F, etc. Biocompatibility evaluation of silk fibroin with peripheral nerve tissues and cells in vitro. Biomaterials. 2007 Mar;28(9):1643-52. Etienne O, Schneider A, Kluge JA, etc. Soft tissue augmentation using silk gels: an in vitro

adhesion. J Mater Sci Mater Med. 2008 Aug;19(8):2827-36.

and in vivo study. J Periodontol. 2009 Nov;80(11):1852-8.

2010 Aug;4(6):464-72.

formic acid processing on tissue reaction to silk fibroin. J Tissue Eng Regen Med.

silkworms: cytotoxicity, biocompatibility and kinetics of L929 murine fibroblast

When a synthetic material is placed within the human body, tissue reacts towards the implant in a variety of ways depending on the material type. The mechanism of tissue interaction (if any) depends on the tissue response to the implant surface. In general, there are three terms in which a biomaterial may be described in or classified into representing the tissues responses. These are bioinert, bioresorbable, and bioactive.

Biomaterials are often used and/or adapted for a medical application, thus comprises whole or part of living structures or biomedical devices which performs, augments, or replaces biological functions. Biomaterials are used in dental and surgical applications, in controlled drug delivery applications. A biomaterial may be an autograft, an allograft or a xenograft used as a transplant material.

Biomaterials are mostly polymers produced by monomers, and are used in artificial organ production in contemporary medicine. They are prepared by the polymerization reaction of certain monomers.

In several previous studies, we investigated whether acrylamide, methacrylamide, Nisopropylacrylamide, acrylic acid, 2-hydroxyethyl methacrylate, 1-vinyl-2-pyrrolidone and ethylene glycol had cytotoxic effects and induced apoptosis or not in spinal cord. Immunolocalization of glial fibrillary acidic protein (GFAP) was also determined, and it was evaluated by using semi-quantitative morphometrical techniques. The cytotoxicity of monomers on cultured fibroblastic cell lines was also examined *in vitro*.

Acrylic acid had the most cytotoxic effect when compared to the methacrylamide and the ethylene glycol groups. GFAP immunoreactivity was found to be rather stronger in the methacrylamide than the other monomers application groups. The methacrylamide, acrylic acid, N-vynil pyrrolidine, acrylamide, N-isopropylacrylamide and 2-hydroxyethyl methacrylate application groups had TUNEL positive cells when compared to the other groups. While some monomers used in biomaterial production seemed not to affect the cell viability and GFAP immunoreactivity, some other monomers had adverse effects on those features. This in turn may contribute to the pathological changes associated to the monomer type.

Histopatological Effect Characteristics of Various

Biomaterials and Monomers Used in Polymeric Biomaterial Production 427

Fig. 1. Fibroblast viability %100 after 12 h incubation period with ethylene glycol

Fig. 2. Fibroblast viability % 0 after 12h incubation period with N-isopropyl acrylamide

Graphic 1. Shows the cell viability alterations between groups in the fibroblastic cell lines by

the time.

In our previous other works, *in vitro* swelling and *in vivo* biocompatibility of radiation crosslinked acrylamide and its co-polymers such as acrylamide (AAm) and acrylamide/crotonic acid (AAm/CA), acrylamide/itaconic acid (AAm/IA), and acrylamide/maleic acid (AAm/MA) hydrogels were investigated.

The radiation crosslinked AAm, AAm/CA, AAm/IA and (AAm/MA) co-polymers were found to be well tolerated, non-toxic and highly biocompatible.

On the other hand, calcium phosphate ceramics and xenografts have been used in different fields of medicine and dentistry. We demonstrated the effects of calcium phosphate ceramics (Ceraform) and xenograft (Unilab Surgibone) in the field of experimentally created critical size parietal bone defects in rats. Although Ceraform was less resorptive and not osteoconductive properties, it could be considered as a biocompatible bone defect filling material having a limited application alternative in dentistry and medicine. However, xenograft seems biocompatible, osteoconductive, and could be used in a limited manner as a filling material in osseous defects in clinical practice.
