Biomaterials.info - Resources for Engineers

Record 161 to 180

[Experimental study on biomaterials coated with titanium-nitride ceramic for orthopedics]
Suka, T. (1986), Nippon Seikeigeka Gakkai Zasshi 60(6): 637-47.
Abstract: Ceramic has excellent properties. However, the brittleness of ceramic is one of the major problems. Coating ceramic on stronger substance materials may be one of the ways to overcome this problem. In this study, stainless steel (316L) coated with titanium nitride ceramic (TiN), produced by using a physical vapor deposition method, was investigated. The results indicated that although the yielding strength was decreased by exposing the material to 550 degrees C, the grain structure did not change. Stainless steel with 3.0 micron TiN coating demonstrated high resistance to bending stress and friction. In addition, this material displayed sufficient fatigue strength for an orthopaedic implant after 10(7) loading repetitions. Based on organ cultures and animal experiments, the biocompatibility of TiN coated stainless steel appeared to be superior to uncoated stainless steel. The TiN coating dissolved in H2O2 although it was stable to HNO3. In conclusion, titanium nitride ceramic coated stainless steel appears to be a promising material for implantation. However, further investigation is necessary for a long term results as an implant material.

[Experimental study on repairing segmental bone defect with bio-derived bone preserved by various methods]
Lan, X., Z. Yang, et al. (2005), Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi 19(2): 95-9.
Abstract: OBJECTIVE: To study the difference of repairing segmental bone defect with bio-derived bone preserved by various methods. METHODS: Freeze-dried biomaterials had been stored in two different preservation solutions for three months, while the biomaterials stored for same period were observed as control group. The experimental model of 15 mm radial segmental defect was made in 60 New Zealand white rabbits, which were divided into groups A, B and C according to transplant materials preserved by various methods. Groups A and B were deeply divided into A1 and A2 subgroups, B1 and B2 subgroups according to whether materials were cocultured with osteoblasts. Tissue engineered bone was used to repair bone defects of left limbs in A1 and B1 subgroups, while simple material to repair defects of right limbs in A2 and B2 subgroups. Group C was divided into C1 and C2 subgroups. Freeze-dried material was used to repair bone defects of the left limbs, while defects of the right limbs as blank control group. The samples were harvested and observed by the roentgenographical, histomorphological, biomechanical and computerized graphical analysis at 4, 8 and 16 weeks. RESULTS: All of the defects treated with implants exhibited new bone formation 4, 8 and 16 weeks postoperatively, increasing with time. The radiological, histomorphological and biomechanical evaluation showed that the ability of new bone formation was arranged in 6 subgroups as follows: A1>A2>C1>B1>B2>C2, the difference was significant between them (P<0.001, P<0.05). The ability of new bone formation was strongest and at 16 weeks the defect was bridged with the appearance of marrow cavities in A1 subgroup, the biomechanical properties in implants approached to those of normal bone. CONCLUSION: The choice of proper preservation solution can improve the ability of repairing bone defect.

[Experimental study on the Biomaterial/Porous Titanium composite dental implants]
Zhou, J. C., G. Y. Xiao, et al. (1993), Shanghai Kou Qiang Yi Xue 2(1): 28-31.
Abstract: This study investigated the tissue compatibility of bone morphogenetic protein (BMP) /biologic ceramic/porous titanium implant,BMP/porous titanium implant,biologic ceramic/porous titanium implant and porous titanium implant by LM,SEM,EDXA.The results showed that the new bone formation and new bone mature were earlier in the BMP composite implants treated group.BMP uncomposite implants had no evident difference in the time of new bone formation, but the interface bonding ways had significant difference.

[Experimental study on the treatment of femur head necrosis with tricalcium phosphate and platelet-rich plasma]
Tao, H., C. Zhang, et al. (2005), Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi 19(3): 170-3.
Abstract: OBJECTIVE: To study the mechanism of compound of calcium phosphate (TCP) and platelet-rich plasma(PRP) in the treatment of femoral head necrosis. METHODS: The left femoral heads of 48 New Zealand white rabbits were frozen by liquid nitrogen as to make the model of femoral head necrosis. Twenty-four rabbits were randomly chosen as the experimental group and their femoral heads were filled with TCP/PRP. The other 24 rabbits were used as the control group and their femoral heads were filled only with TCP. They were sacrificed at 2, 4, 8, 12 weeks after operation. The specimens were examined with X-ray and histological study. RESULTS: At 2 weeks after operation, there was no significant difference in femoral head density between the two groups. Four weeks after operation, femoral head density decreased in both groups, while it decreased more in the control group. At 8, 12 weeks after operation, the density of the femoral heads in both groups increased, and it was higher in the experimental group. Histology examination showed that there was no difference between the two groups 2 weeks after operation. The head became flat at 4 weeks. Control group had more defects. At 4, 8, 12 weeks, more repairs were observed in the experimental group than that in the control group. The amount and maturity of osteogenesis in experimental group were much more greater than those in control group. Bone histomorphometry showed that the volume of the trabecular was larger in the experimental group (36.65% +/- 7.22%, 38.29% +/- 4.28%, 39.24% +/- 3.42%) than that of control group (P < 0. 05). CONCLUSION: TCP/PRP does not only provide osteoblasts scaffold, but also promotes bone formation and the head repair. TCP/PRP is a good biomaterial for the treatment of femur head necrosis.

[Experimental study using 86Rb on the permeability of biomaterials used for occlusal pit and fissure sealants]
Neumann, C. P., V. Rusu, et al. (1998), Rev Stomatol Chir Maxillofac 99 Suppl 1: 76-8.
Abstract: In experimental in vivo work, we used 45Ca and 131I radioisotopes to establish the impervious nature of biomaterials used for filling. A comparative study of permeability in 3 biomaterials used as pit and fissure sealant, alkylcyanoacrylate, Delton and Sigilar was conducted with 86Rb radiosotope. The materials were applied to the surface of 60 natural intact teeth divided into 3 sets and 6 groups. Each of the 3 types of materials were applied no one set of teeth. Within each set, a group of 10 teeth were labeled with 86Rb for 30 minutes and the other group was marked with 86Rb for 60 minutes. After washing, gamma emission was measured immediately after labeling then again 24 hours later. Results indicate that the biomaterial Delton is the least permeable to 86Rb, gamma counts being approximately 20-times lower with Delton than with alkylcyanoacrylate and Sigilar.

[Experimental-morphologic study of bone tissue reaction to carbon-containing material implantation with initiated X-ray contrast property]
Grigorian, A. S., F. Nabiev, et al. (2005), Stomatologiia (Mosk) 84(2): 4-9.
Abstract: In experimental study on 15 rabbits (chinchilla) influence of titanium plates implanted lapped on adjacent tissues in the region of the lower jaw body (comparison group) and carbon material with added boron in the concentrations of 8 and 15% (the study group) was studied. Results of the experimental-morphological investigation show that carbon-based materials with boron addition (with its content 8 and 15%) did not impede adaptive rebuilding of bone tissues and in particular bone structure regeneration in the process of reactive rebuilding of the "maternal" bone. Moreover, as the result of reactive processes developing in osseous tissues after implantation of the tested materials their successful integration in surrounding tissue structures was detected.

[Failures of endoscopic treatment of vesico-ureteric reflux in children using Macroplastique]
Kouame, B. D., C. Szwarc, et al. (2005), Prog Urol 15(2): 291-5; discussion 295.
Abstract: INTRODUCTION: Macroplastique has been used since 1993 for the endoscopic treatment of vesico-ureteric reflux in children with a failure rate per injected ureteric unit of 21%. The objective of this study was to analyse these failures on the basis of endoscopic findings on injection, ultrasound data at 2 months post-endoscopy and operative findings during the secondary reimplantation. MATERIAL AND METHODS: The authors retrospectively reviewed cases of failure of Macroplastique treatment from September 1993 to December 2002. Only children undergoing subsequent surgical reimplantation were included in the study: 60 cases (57 girls, 3 boys). Another 68 patients also presented recurrence of reflux, but are currently asymptomatic and have not been reoperated. Twenty five patients (42%) initially presented unilateral vesico-ureteric reflux: bilateral injection was performed in 17 of these cases because of the anatomical findings on endoscopy. In 92% of cases, the refluxing ureteric orifice appeared to be abnormal (in terms of position, appearance and the submucosal course of the ureter). RESULTS: Eleven children (18%) presented symptomatic or asymptomatic urinary tract infection before the first clinical and radiological review at 2 months. On the first ultrasound examination, the implant was visualized in the bladder wall in 71% of cases. At reimplantation, the bladder mucosa was inflammatory in 56 patients (94%). The ureteric orifice remained gaping in 38% of cases and the implant appeared to be modified (migration, decreased volume) in 35% of cases. CONCLUSION: Failures of endoscopic treatment by Macroplastique can be due to persistence of pre-existing ureteric anatomical lesions (poor indication, technical error or difficulty) or modification of the injected product. Bladder inflammation and therefore previous or post-endoscopy urinary tract infections may also play a role.

[Femoral implants of coral and ceramics: histological results after 120 days]
Diallo, A. S., M. Diarra, et al. (2002), Dakar Med 47(2): 197-201.
Abstract: The authors have made an histological study of the evolution, after 120 days, of coral implant and tricalcic phosphate ceramic implant in each femur of 12 rabbits. The results have shown on the one hand that ceramic is resorbed faster than coral, on the other hand that for both types of biomaterials the resorption was much faster for the implants in contact with the bone-marrow than for those which were not.

[Formation of the allogeneic tissue engineered cartilage using injectable biomaterial]
Luo, J. S., G. Z. Li, et al. (2001), Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi 15(5): 273-5.
Abstract: OBJECTIVE: To study the feasibility of the formation of allogeneic tissue-engineered cartilage of certain shape in immunocompetent animal using the injectable biomaterial. METHODS: Fresh newborn rabbits' articular cartilages were obtained under sterile condition (< 6 hours after death) and incubated in the sterile 0.3% type II collagenase solution. After digestion of 8 to 12 hours, the solution was filtered through a 150 micron nylon mesh and centrifuged, then the chondrocytes were washed twice with phosphate buffered saline (PBS) and mixed with the biomaterial to create a final cell density of 5 x 10(7)/ml. The cell-biomaterial admixture was injected into rabbits subcutaneously 0.3 ml each point while we drew the needle back in order to form the neocartilage in the shape of cudgel, and the control groups were injected with only the biomaterial or the suspension of chondrocytes with the density of 5 x 10(7)/ml. After 4, 6, 8 and 12 weeks, the neocartilages were harvested to analyze. RESULTS: The new nodes could be touched subcutaneously after 2 weeks. In the sections of the samples harvested after 4 weeks, it was found that the matrix secreted and the collagen formed. After 6 weeks and later than that, the neocartilages were mature and the biomaterial was almost completely degraded. The cudgel-shaped samples of neocartilage could be formed by injection. In the experiment group, there was no obvious immune rejection response. On the contrary, there were no neocartilage formed in the control group. CONCLUSION: The injectable biomaterial is a relatively ideal biomaterial for tissue engineering, and it is feasible to form allogeneic tissue engineered cartilage of certain shape by injection in an immunocompetent animal.

[Free and conjugated forms of salicylic acid: content and role in potato]
Panina Ia, S., N. I. Vasiukova, et al. (2005), Prikl Biokhim Mikrobiol 41(3): 354-7.
Abstract: Hydrolysis of conjugated forms of salicylic acid and accumulation of its free form was observed after infection of potato tubers (Solanum tuberosum L.) with an incompatible race of phytophthora or treatment with an elicitor (chitosan). Infection of tubers with a compatible race of the pathogen or treatment with a suppressor (laminarin) decreased both the degree of hydrolysis of conjugated forms of salicylic acid and the accumulation of its free form.

[Fundamental studies of adhesion mechanisms of cultured cells to biomaterials]
Kimura, M. (1987), Kanagawa Shigaku 22(1): 76-89.

[Gas chromatographic determination of hexachlorobutadiene in biomaterials]
Khalturin, G. V. and N. I. Andriushkeeva (1982), Gig Sanit(10): 61-2.

[Gel chromatography as a method of purifying extracts of biomaterial containing barbiturates]
Popova, V. I. (1977), Farm Zh(6): 70-1.

[Growth behavior of chondrocytes on various biomaterials]
Rudert, M., F. Hirschmann, et al. (1999), Orthopade 28(1): 68-75.
Abstract: Chondrocytes can be cultured on different three-dimensional culture systems suitable for transplantation to enhance the repair of localized cartilage defects. Articular cartilage chondrocytes from adult rabbit knees and from bovine calf metacarpophalangeal joints were isolated by enzymatic digestion and cultured in a monolayer system to amplify cell count. After amplification the cells were seeded on different biocompatible materials. We investigated two types of bioresorbable polymer fleece matrices (a composite fleece of polydioxanon and polyglactin and a resorbable poly-L-lactic acid fleece) and lyophilized dura as a biological carrier. On all three types of transport media the phenotypic and morphological appearance of cultured chondrocytes could be observed. The production of glycosaminoglycans was revealed by Alcian blue staining and immunohistochemical detection of Chondroitin-4 and 6-sulfate in the created constructs. The material properties of the carriers allow for transplantation of the artificial cartilage-like products into full thickness articular cartilage defects and could therefore improve the minor intrinsic healing capacity of cartilage tissue. Bioartificial cartilage may become a future perspective in the treatment options of orthopaedic and plastic surgery.

[High tibial open-wedge osteotomy using a tricalcium phosphate substitute: 70 cases with 18 months mean follow-up]
Dehoux, E., K. Madi, et al. (2005), Rev Chir Orthop Reparatrice Appar Mot 91(2): 143-8.
Abstract: PURPOSE OF THE STUDY: We report our experience with a B tricalcium phosphate ceramic to fill open-wedge tibial osteotomy gaps. MATERIAL AND METHODS: Seventy high tibial open-wedge osteotomies were performed in 70 patients (47 men and 23 women). Ostotomy was performed for osteoarthritis in 56 knees, Ahlback classification stage I (n = 18), stage II (n = 32), stage III (n = 6) and for congenital varus in 14. Mean patient age was 45.2 years (16-69). We used a wedge-shaped piece of ceramic with an appropriate angle, which was associated with granulated material to complete the gap filling for the last 20 cases. One or two staples were used for fixation. Clinical and radiological outcome was assessed at 6 weeks, 3 months, 6 months, and at last follow-up. Mean follow-up was 18 months. RESULTS: There were no biological or clinical complications related to biomaterial intolerance. Tolerance to the osteosynthesis material was mediocre since we observed one infection and 12 cases of pain related to the staples which required material removal in 8 patients. Bone healing was achieved in 98.5%. Final correction was between 3 degrees and 6 degrees valgus in 80.5%. There was a loss of correction angle between the postoperative film and the bone healing film. Factors related to sustained correction were: non-fractured wedge, intact lateral tibial cortical, osteosynthesis with two staples. Osteointegration was good and rapid in 96%. We found two complete lucent lines at last follow-up but with variable resorption depending on the shape of the bone substitute. CONCLUSION: Use of a ceramic wedge to fill high tibial medial open-wedge osteotomy gap is a reliable reproducible technique providing correction without formation of a malalignment callus. Bone healing is achieved in 98.5% of the cases at about three months. Osteointegration is good in 96%. Resorption is complete and rapid when the substitute is implanted in granular form in a cancellous zone and is partial and slow when implanted as a massive wedge.

[Histo-pathological studies of periodontal tissue reactions after furcation perforations treated with various inorganic biomaterials in dog teeth]
Hinoide, M. (1985), Shikwa Gakuho 85(5): 571-611.

[Hybrid biomaterial]
Emi, N. (1995), Tanpakushitsu Kakusan Koso 40(17): 2514-8.

[Hydroxylapatite ceramics--a bone-like biomaterial. Preliminary report]
Osborn, J. F. and T. Weiss (1978), SSO Schweiz Monatsschr Zahnheilkd 88(10): 1166-72.
Abstract: Inorganical materials are being increasingly tried out in surgery and periodontal surgery for reconstructing bone defects. This paper discusses the biocompatibility and biofunctionality of different implant materials and presents a new hydroxyapatite ceramic material, of which a good bioactive behaviour is expected.

[Hydroxylapatite ceramics--development of a new biomaterial and 1st animal experimental results]
Osborn, J. F., E. Kovacs, et al. (1980), Dtsch Zahnarztl Z 35(1): 54-6.

[Identification and quantitation of selenocompounds in environment and organism]
Chen, X. B., S. B. Lin, et al. (2005), Wei Sheng Yan Jiu 34(3): 371-4.
Abstract: Identify and quantify of diversity of selenocompounds in environment and organism is necessary to further understand and fairly evaluate the effects of selenium in clinical chemistry, nutrition, toxicity, environment and ecology. For the purpose, many state-of-the-art of analytical techniques are applied with the particular emphasis on the effective isolation, high-sensitively element-selective detection and the identification of the detected selenocompounds. Some practical and recently-developed methods, especially Se speciation by the combination of chromatography with mass spectrography, are here reviewed, which is of benefit to the deep researches on the selenium species in environmental samples and biomaterials.

First Page

Last Page