Titanium sterilization

The first ever injectable crude biomaterial, that is a dental implant, appeared early in ad 6oo (Fig. 12.1). During those times, Mayan people trimmed seashells into artificial teeth to replace missing teeth (Michael, 2006 Ratner et al., 2004). Early biomaterials also led to problems, including sterilization, toxicity, inflammation, and immunological issues. Since the Mayan s initial use of artificial teeth, biomaterials have evolved to be used in modem artificial hearts, hip and knee pros-theses, artificial kidneys, and breast implants. Materials used in these applications include titanium, silicons, polyurethanes, teflon, polybiodegradable polymers, and most recently bio-nanomaterials (Pearce et al., 2007)... 

Syndiotactic Polystyrene. Syndiotactic polystyrene is an interesting material because it has a Tg of 95 °C and a Tm of 260 °C [38], Polystyrene made via radical polymerisation may show some syndiotacticity, but its heat distortion temperature is too low to allow its use in important applications requiring temperatures around 120 °C or higher, such as medical equipment which requires sterilization or hot water storage containers. Idemitsu and Dow have reported titanium-based catalysts such as the one shown in Figure 10.23. We presume that the mechanism is a chain-end controlled "2,1" insertion. 

Abstract A colloidal solution of titanium dioxide (TiO ) nanoparticles was prepared by the solvothermal method and dip-coated onto a polypropylene fabric with TMOS binder. The prepared TiO particles, colloidal solution and the coated fabrics were characterized by X-ray diffraction, SEM and TEM. The results showed that the TiO particles prepared by the solvothermal method were composed of anatase which uniformly coated the snbstrate. Photocatalysis induced bactericidal properties of coated fabrics were tested by measuring the viability of Escherichia coli. It was fonnd that solvothermally prepared TiO coatings have the ability to kill E. coli. This nniqne property of TiO makes it an ideal candidate in producing self-sterilizing protective masks and in providing bactericidal and self-cleaning properties to a variety of snrfaces. 

Horie Y, Taya M, Tone S. Evaluation of photocatalytic sterilization rates of Escherichia coli cells in titanium dioxide slurry irradiated with various light sources. J Chem Eng Jpn 1998 31 577-584. 

NT-501 is an ECT-CNTF product that consists of encapsulated cells that secrete recombinant human CNTF. After implantation, CNTF is released from the cells constitutively into the vitreous gel. The NT-501 implant is manufactured to be sterile, nonpyrogenic, and retrievable. The current implant or capsule is about 1.1 cm in length (including titanium loop) and will be placed well outside the visual axis in the human eye. This same implant and implant size has been used in preclinical toxicity and efficacy evaluation studies in dogs, pigs, and rabbits. The therapeutic intent of intraocular CNTF delivery is to reduce or arrest the progressive loss of photoreceptors, which is characteristic of retinitis pigmentosa (RP) and related retinopathies. 

Since our pioneering study on as-received [22] nickel-titanium endodontic instruments, other DSC studies have confirmed that as-received instruments are in the superelastic condition, which persists after numerous sterilization cycles [28,29]. As would be expected, mechanical properties of these instruments are related to the phase transformation behaviour of the nickel-titanium alloy [30]. Accordingly, suitable elevated-temperature heat treatment may favourably alter the mechanical properties of these instruments [31,32], as was previously found for nickel-titanium orthodontic wires [21,33]. 

Singh, S. and Schaaf, N.G. 1989. Dynamic sterilization of titanium implants with ultraviolet light. Int. ]. Oral MaxiUofac. Implants 4 139. 

Stanford, C.M., Keller, J.C., and Solursh, M. 1994. Bone ceU expression on titanium surfaces is altered by sterilization treatments. J. Dent. Res. 

Vezeau, RJ Keller, J.C., and Koorbusch, G.R 1991. Effects of multiple sterilization regimens on fibroblast attachment to titanium. /. Dent. Res. 70 530. 

Select . Modular titanium stem humeral prostheses with keeled and pegged UHMWPE glenoid components sterilized by gamma in an oxygen-free environment. Developed with Dr. Wayne Burkhead, it was introduced in 1987. It is intended for primary, hemiarthroplasty, total, and fracture use with cemented fixation. 

Foundation and Foundation fracture. Modular titanium stem humeral prostheses with keeled and pegged UHMWPE glenoid components sterilized... 

Modular Shoulder System. A modular titanium stem humeral component with a keeled UHMWPE glenoid component sterilized by EtO. Cobalt chromium, titanium nitrite, and ceramic humeral heads are available as part of the system. It is intended for primary, hemiarfhroplasty, total, and fracture use with press-fit fixation. 

Next we applied this assay to the assessment of a nickel-titanium alloy [18]. We selected MOLT-3 that was the most sensitive against nickel ion (see Fig. 11). Nickel-titanium (NiTi) alloys were made by an arc melting method. Those alloys varied greatly in composition (Table 3) and phase (Fig. 12). First these alloys were sterilized by soaking them in 70 % ethanol solution. Then they were immersed in phosphate buffer and incubated at 36.5 °C for 25 h. We collected the extract and added it to a MOLT-3 culture plate (the ratio of extract to supernatant was 1 1). After a 4-day culture, we measured the viable cell number of each culture condition. The order of the viable cell numbers was coupon 5> coupon 2> coupon 1, coupon 3> coupon 4 (Fig. 13). We also measured the nickel concentration of the extract by atomic absorptirai spectrophotometry. The order of the nickel concentration was coupon 4> coupon 1, coupon 3> coupon 2> coupon 5 (Table 4), which was... 

Gradient epoxy rq)licas (five replica substrata per time period) were placed in 24-well plates together with epoxy replicas of SLA (sandblasted and acid etched) cpTi discs (Institut Straumann, Basel, Switzerland) [20] and titanium-coated Thermanox discs (Nunc, Wiesbaden, Germany) as reference surfaces. Substrata were sterilized and the surface activated by oxygen-plasma treatment (Harrick Plasma, Ithaca, USA) for 4min. Immediately after the plasma treatment, the substrata were covered with media (a-DMEM with 10% foetal bovine serum and 1% antibiotics). 

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