PENGEMBANGAN KOMPOSIT POLIVINIL ALKOHOL (PVA)�HIDROKSIAPATIT BOVINE DENGAN PENGUAT CATGUT DAN GLUTARALDEHID SEBAGAI CROSSLINKER UNTUK MATERIAL FIKSASI PATAH TULANG RAHANG

Abstract

The use of bone fracture fixation devices has become routine procedure by using a rigid material such as titanium. The strength and stiffness of the material are too high causes atrophy of the underlying bone. Some other disadvantages led to the need for secondary surgery to remove the device. Biodegradable bone fracture fixation material developed to overcome the disadvantages of metal fixation and avoid secondary operations. Use of Polyvinyl Alcohol (PVA) increases in several biomedical applications that do not require high mechanical strength. In this study, catgut that has been used for absorbable suturing wounds has woven to act as a reinforcement. Bovine hydroxyapatite (HA) was used as filler material has a bioactive and osteoconductive materials and has a good biocompatibility. To improve the mechanical strength was also used glutaraldehyde as a crosslinker to the PVA. The aim of the study was to determine whether the catgut reinforced Polyvinyl Alcohol (PVA)�bovine HA composites and glutaraldehyde as a crosslinker having adequate and stable mechanical strength of bone fracture fixation material and has good biocompatibility without toxicity and hypersensitivity reactions in experimental animals after biodegradation tests for 30 and 60 days. Methods of research were obtained by the tensile and bending specimen tests with any concentrations. In vitro biodegradation test was performed by immersing the specimens in PBS solution of pH 7.4 at the 37 oC for 30 and 60 days. Specimen weight, tensile and bending strength, characterization included FT-IR and SEM studies were performed before and after immersion. Finally, in vivo biocompatibility tests, including type IV contact hypersensitivity and local toxicity tests were performed. The results showed there was a slight decrease of the specimen mass weight mean in all groups due to polymer PVA dissolved. Mechanical tests showed the catgut reinforced Polyvinyl Alcohol (PVA)� bovine HA (60:40) weight fraction composites and glutaraldehyde as a crosslinker had the highest mechanical strength mean, were 43.06±0.18 MPa in the tensile strength and 46.04±2.57 MPa in the bending strength before immersion. There were a decreased in the tensile strength and the bending strength after immersion for 60 days. The mechanical strength had still above the masticatory muscle strength which can lead to tensile and bending forces to mandibular bone fractures, about to 25 MPa. The results showed that the catgut reinforced Polyvinyl Alcohol (PVA)�bovine HA (60:40) weight fraction composites and glutaraldehyde as a crosslinker had adequate and stable mechanical strength as the bone fracture fixation material after biodegradation test for 30 and 60 days. The FT-IR characterization study showed functional groups increases of composites. SEM study showed the morphological changes of the catgut reinforced Polyvinyl Alcohol (PVA)�bovine HA (60:40) weight fraction composites and glutaraldehyde as a crosslinker. FT-IR and SEM studies showed the biodegradation process with polymer PVA dissolved after immersion for 30 and 60 days. The biocompatibility tests showed that the material had not caused hypersensitivity and toxicity reactions in experimental animals. It can be concluded that the composites can be developed for biodegradable bone fracture fixation material as titanium substituted