Abstracts Posters SICOT-SOF meeting Gothenburg 2010 _2_

Poster
Topic: Biomaterials
Abstract number: 26013
COBALT CHROME ALLOYS FOR IMPLANTS - A STUDY ON RABBIT
Florian PURGHEL 1 , Radu CIUVICA 1 , Constantin JEMNA 1 , Andrei ANASTASIU 1 ,
Nicolae SABAU 2 , Traian ZAHARESCU 2 , Lidia PURGHEL 3
1 "Bagdasar-Arseni" Clinical Emergency Hospital Bucharest, Bucharest (ROMANIA),
2 National Institute of Heat Engines, Bucharest, Magurele (ROMANIA), 3 National
Institute of Physics and Nuclear Engineering "Horia Hulubei", Magurele (ROMANIA)
INTRODUCTION: Cobalt-chrome alloys are some of the most used and very well
tolerated metallic biomaterials, used for osteosynthesis, and especially in producing
internal hip and knee prosthesis. OBJECTIVE: The aim of this study was to obtain a
cobalt-chrome type alloy, using Romanian raw materials and conception. In order to
be used as a model for producing of metallic hip endoprostheses, the prototype was
obtained. MATERIALS AND METHOD: The cobalt-chrome-molybdenum alloy
(stellite) has a chemical composition similar to the imported stellite named Vitallium,
with lower carbon and iron contents. The corrosion tests were made in vitro, with
oxalic acid 10% and chlorhydric acid 1/1, and in vivo, by implantation in rabbits for 90
days.After 90 days the following tissues were analyzed:-the metallic implant
electronic microscopy-the debris -the interface tissues - EDXA, AAS, electronic
microscopy, histological, histochemical studies. RESULTS: Mechanical
characteristics: fracture strength determined by traction test: 851 N/sqm;-elongation:
18.6%;- density: 330 HV. Interface tissue analysis:- EDXA- no presence of
Fe, Ni, Co, Mo; AAS Co 0.30-0.42 mg/100 gr. dry tissue (N = 0.28-0.47 mg %)Cr
0.68 -0.74 mg/100 gr (N = 0,55 mg %)Fe 5.87 - 9.38 mg % (N = 5.54 mg %)- SEM
and TEM (scanning and transmission electronic microscopy) - granulation tissue with
sclerotic organization, numerous cells, mastocytes. CONCLUSION: The conception
and elaboration of a biomedical Co-Cr alloy requires high technology (vacuum
induction furnace) and special projected chemical composition.
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