Advances in Wear and Tribocorrosion Testing of Artificial Implants and Materials: A Review.
In general, medical implants are devices made of body tissues or artificial materials (i.e. metal, ceramic, plastics) that are placed inside or on the surface of the body to provide support or repair and restore functionality of a body part. The artificial implants inserted into body will undergo some degradation due to electrochemical reaction and wear under the physiological environment [1,2]. Implant wear is an important aspect which determines proper selection of biomaterial and implant design. Further, the nature, size and distribution of wear debris released into the body from implants are also an important issue. However, the effect of wear and wear debris on performance of implants is more prominent for the orthopaedic implants, more specifically in load bearing joint implants such as total hip implant, knee implant, shoulder implant [1,3]. Artificial joint replacements are exposed to different loading and sliding conditions and therefore prone to wear. F or example, the contact area between hip stem shank and the femoral head is subjected to fretting wear. In addition, the wear of acetabular or tibial liner made of ultra high molecular weight polyethylene (UHMWPE) can be very severe. The micrographs of retrieved implants shown in Fig. 1 demonstrate the wear and fracture of UHMWPE liner used in artificial hip and knee implants.
Different material pairs have been explored with an aim to reduce the friction and wear in artificial joint replacements. Today CoCrMo alloy, ultrahigh molecular weight polyethylene (UHMWPE), ceramics such as alumina and zirconia toughened alumina and other coatings such as TiN, DLC and ZrO2 are widely being used as articulating bearings . The most popular bearing combinations include metal-on-polymer (MoP), ceramic-on-polymer (CoP), ceramic-on-metal (CoP) and ceramic-on-ceramic (CoC). These artificial implants experience different types of wear and their fundamental wear mechanisms have also been identified [1-3,8,9]. The main purpose of this review is to highlight the recent considerations on the importance of wear test methodologies that are close to clinically relevant environmental conditions, the role of tribocorrosion on wear and the continued importance of overall wear of artificial load bearing implants in their long-term survival.
Types of wear in artificial implants
Synovial joint replacements such as hip and knee are exposed to extremely high loads during daily activities and therefore subjected to wear. Although the loads are smaller, the oral environment is extremely aggressive, due to variety of foods, and therefore, wear of dental implants is gaining equal importance. In general, for long-term stability of artificial implants, their chemical and mechanical properties must be stable over a long period of time. Presence of biological moieties such as proteins can significantly alter the surface reactions leading to corrosion thereby enhancing the wear rate while they can reduce or increase the friction. As a result the wear and corrosion induced damage promote premature implant failures. For example, the ultrahigh molecular weight polyethylene (UHMWPE) debris generated as a result of wear in hip and knee has been identified as the major cause of osteolysis, instability and implant loosening [10-14]. In addition to UHMWPE, the metallic counter parts also release some metal ion and debris, which can be demonstrated to inhibit several cellular activities of osteoblasts and osteoclasts . Further, the occurrence of inflammation, metal ion sensitivity and carcinogenicity has been directly related to dissolution of these wear debris [15,16]. Types of wear and their mechanism in artificial implants are very complex and depend on several interdependent variables related to materials composition, properties, contact stresses, lubrication etc. [8,17]. In general, the prevailing wear mechanism in orthopaedic and dental implants can be categorized as adhesive, abrasive, fretting, fatigue and corrosion [9,18-22]
Abrasive wear: This type of wear is characterized by loss soft material due to sliding of hard and rough surface against it. The abrasive wear damage can occur via two-body or three-body wear mechanisms, as shown in Fig. 2a. The overall wear starts with former mechanism and leading to three-body wear. In the former, the hard surface cuts and removes the soft material forming deep grooves. The removed particles entrap between the two articulating surfaces and result in third-body wear via rolling and sliding across the soft surface. Characteristic features typically observed on surfaces damaged by this type of wear include plowing, cutting and fragmentation (brittle materials). The scale of these features depends on size of third-body particles, initial roughness and hardness of articulating pairs . In THA and TKA third-body abrasive wear originates due to loose bone cement particles and typical abrasive wear features are shown in Fig. 2b.
Adhesive wear: This type of wear occurs when asperities of articulating materials fuse together, under the influence of pressure, and rupture subsequently due to relative motion leading to transfer of small material from one surface to other surface, as shown in Fig. 3a. Presence of any films separating the articulating surfaces can avoid adhesive wear. Therefore, adhesive wear is often observed in the regions where the lubrication is lost. The process starts with penetration of asperities of hard surface in to soft surface and in the plastically deformed region the two materials join together via micro-welding and adhesion. When these joined regions experience sufficiently high shear stresses, due to relative sliding motion, and they rupture leading to transfer of micro-joined regions to one of the articulating surfaces. Typical adhesive wear features on different bearing couples is shown in Fig. 3b.
Fatigue wear: The fatigue wear is a localized, progressive structural damage that occur when contact asperities experience high, local cyclic loads (higher than fatigue strength of the material) during articulation. Typically the damage starts at materials' surface (with high friction) and the cracks grow, penetrate deep and later coalescence leading to separation of small pieces of material from the surface. As shown in Fig. 4a, the fatigue wear can be either macroscopic or microscopic. The damage cover large area in macroscopic fatigue wear therefore the consequences are often catastrophic. On the other hand, the microscopic fatigue wear is a phenomenon localized to individual asperities . Being a soft material ultra-high molecular weight polyethylene (UMWPE) is prone to fatigue wear in THA and TKA . Examples are fatigue wear are shown in Fig. 4b.
Fretting wear: This type of wear occurs in the presence of cyclic stresses and small-amplitude oscillatory movements (typically less than 500 [micro]m) between two contact surfaces. Schematic illustration of fretting wear is shown in Fig. 5a. The characteristics features of fretting wear include localized regions of heavy plastic deformation, spalling and embedded particles with oxidized surface. The failure of the implant due to fretting wear originates from surface generated cracks and typically such wear has been observed on taper bore of femoral head and mating hip stem neck. Example of hip and dental implants failed due to fretting wear are shown in Figs. 5b and 6, respectively.
Corrosion wear: This is a damage induced by simultaneous influence of wear and corrosion. During corrosion wear, the surface chemically reacts with the environment forming oxide layers which can easily detach from the surface under the influence of mechanical wear leading to pitting and third-body abrasive wear. In general, the damage becomes more severe in corrosion wear compared to corrosion and wear occurring independently. This is because the rubbing action removes the protective passive layer from the surface and prevents its reformation. Similarly, the oxide layers form as a result of corrosion are brittle and removed from the surface under the influence of relative movement between articulating materials. Corrosion wear is most widely observed wear mechanism in orthopaedic, dental and other articulating implants, as these implants are always in contact with physiological fluids. The failure of implants can occur due to corrosion wear via pitting, fretting and stress corrosion cracking.
Factors effecting wear
Apart from type of materials combination, wear of the articulating surface also depends on several other factors such as surface conditions (roughness, hardness and wetting behaviour), manufacturing techniques (wrought, heat treated or sintered), microstructure, lubrication, clearance and design aspect [7,34-39]. Surface roughness of articulating surface is an important factor that strongly affects wear. The rough surface of hard femoral components can increase UHMWPE wear via adhesive and abrasive wear mechanisms [40,41]. The change in roughness by an order of magnitude can increase wear rate in the order of 2 to 3- fold . In order to reduce the friction and wear of bearing surface, international standards clearly specify the roughness (Ra) limits in the range of 0.02 and 0.10 [micro]m for femoral components of different materials and greater than 2 [micro]m for UHMWPE components . Further, the surface roughness along with surface chemistry/composition, sometimes crystallographic texture influences the wettability/interfacial energy of the surface. High wettability of articulating surface helps in adsorption of different proteins from physiological environment thereby forming an interfacial tribofilm between articulating materials and consequently can decrease the friction [43,44]. In vivo wear rate and friction coefficient are influenced by the wettability of articulating biomaterials [27,45]. The dependence of coefficient of friction on surface wettability (in terms of contact angle, q) and components of surface energy ([g.sub.polar] and [g.sub.dispersive]) was studied by Pawlak et al  and its was demonstrated that the friction coefficient is strongly dependent on the level of wettability of articulating materials (Dq = [q.sub.1] - [q.sub.2]). Further, due to the presence of ionic nature the ceramics surfaces showed greater wettability compared to that of metals. They readily chemisorb protein from body fluid thus forming lubricating films which can potentially reduce the coefficient of friction, which has been demonstrated with water . These observations were substantiated by recent in vitro tribological experiments on ZrO2 coatings , bulk ceramics  and TiO-TiN coatings , where considerable improvement in wettability and consequent reduction in wear rate were observed during standard tribometer tests. Other important aspects of any bearing surface are ideal operating clearance and lubrication. Wang et al.  found that lower radial clearances resulted in lower coefficients of friction, at various loading, and therefore less wear. Friction and wear of bearing surface depends on lubrication film thickness, which to some extent depends on the clearance. There are three main lubrication modes observed based on ratio of the fluid-film thickness to the surface roughness (l).
I. Boundary lubrication: the sliding surfaces are separated by molecules or tribo-film attached to one or both surfaces. The film thickness is limited compare to the roughness of the surfaces where the ratio, l<1.
II. Fluid film lubrication: the sliding surfaces are separated by a thick fluid film where the ratio, l>3. It is also called full film lubrication. In load bearing joint implants, the formation of such film depends on the implant design, loads on the joint, surface sliding velocity and lubricant properties .
III. Mixed lubrication: it is intermediate lubrication regime between boundary and hydrodynamic lubrication mode where l varies between 1 and 3 (1<l<3). This mode of lubrication prevents the sliding surface from direct contact. In this mode coefficient of friction is higher compare to full film lubrication but relatively low wear rate .
Study of lubrication model for joint implant in vivo is quite different from its natural joint due change in local biological system. Actual mechanisms are still a matter of debate. Wang et al.  suggested that fluid film lubrication was less effective for the metal on polyethylene joints. Recently the lubrication modes of the artificial hip joints with different materials combinations has been predicted by Scholes and Unsworth . Their research claimed that mixed lubrication mode prevailed for both MoP and MoM joints. Whereas full film lubrication was predicted for all ceramic joints due to much lower surface roughness of the ceramic components.
Wear test methods
New materials and devices developed for articulating implant applications must be evaluated in terms of tribological properties such as wear rate and coefficient of friction to avoid undesirable effects and failures in vivo. For efficient tribological evaluation of materials and devices the test conditions must be as close as possible to physiological movements and loads. Therefore, the wear testing methods can be categorized in to two groups (i) Wear screening tests, and (ii) joint simulator tests. The former tests are quick tests primarily used to screen/rank different materials based on their intrinsic wear rate. The joint simulator tests utilizes special machine that can simulate clinically relevant movement and loading conditions similar to those prevailing in in vivo service conditions. In these tests full size joint replacement devices are tested for their long-term tribological performance.
Wear screening tests: These quick and affordable tests are very useful in evaluating newly developed materials intended for articulating joint replacement applications. These tests provide good understanding of tribological properties and behavior of materials, which enable initial screening and ranking of different materials, under consideration, before full-scale evaluation using joint simulators followed by in vivo testing. Since the join simulator testing involves evaluation of materials along with implant design these tests are costly pin-on-disc type wear screening tests have been developed. However, the specimen geometry is simplified in these tests and therefore, the contact stresses and lubrication are different from those observed during in vivo service. Fig. 7 shows important wear screening test configurations, which include rotating ball/pin-on-disc, linear reciprocating ball/pin-on-disc, ball & crater, twin disc and one-way slide testing [21,54-56]. These tests are normally carried out at room temperature or 37 [+ or -] 1[degrees]C in variety of fluids such as Ringer's solution, Hank's solution, phosphate-buffered solution, artificial saliva, with and without serum/ proteins to simulate physiological conditions.
The wear rates of UHMWPE determined using standard pinon-disc testing with unidirectional and reciprocating motion (~[10.sup.-8] [mm.sup.3]/Nm) were found to be one to three orders of magnitude smaller than in vivo wear rates (~[10.sup.-6] [mm.sup.3]/Nm) of THA [57-61] and TKA [57,58,61-63]. This is primarily due to significant difference in test parameters such as sample geometry, contact stresses, contact area, multi-directional movements, surface roughness, between these tests and in vivo conditions . Further, the test parameters of these simple wear tests cannot predict operating wear mechanisms that are clinically relevant [65,66] and it is difficult to replicate in vivo conditions in these simple screening tests. However, these tests are extremely important to determine relative wear rate of different materials enabling their ranking before device level testing.
The first multi-directional pin-on-disc testing was reported by Charnley  in 1976. Later multi-directional movement was found to have strong influence on wear of UHMWPE tested in hip joint simulators [58,68]. Wear rates and wear mechanisms similar to those observed on retrieved hip implants have been obtained using multi-directional pin-on-disc testers . Following this, several other investigators examined the wear rate of UHMWPE using multi-directional wear testers and established the influence of cross-shear on its wear [62,63,65,66,69-72]. The use of multi-directional pin-on-disc testers enabled better ranking of materials in terms of their wear rates matching closely with the data obtained using joint simulator testing .
Multi-directional pin-on-disc testing performed on [Al.sub.2][O.sub.3]-on-[Al.sub.2][O.sub.3] THA articulation also showed overall tribological behavior that is known to occur in vivo . Such good correlation has been achieved primarily due to continually changing sliding direction of articulating materials. The relation between wear rate and mechanism, and type of relative motion has been systematically studied [75-77] which established good correlation with clinical observations . Later programmable random pin-on-disc (Random POD) testers, shown in Fig. 8 (left), with ability to produce virtually any type of movement (Fig. 8, right) and loading profiles have been developed [69,79]. Recent tests with random and circular motions showed that former could lead to drastic increase in the wear rate of UHMWPE as shown in Table 1 [69,79]. Similarly Baykal et al  showed that multi-directional motion resulted in about a 26 times increase in the wear compared to that observed with simple "circular" motion in POD testing. These Random POD wear test systems have been demonstrated to simulate wear mechanisms prevailing in well-functioning hip and knee . These studies also confirmed that relative motion between articulating materials play an important and decisive role in overall tribological performance. Comprehensive and systematic review of multidirectional pin-on-disc wear testing of biomaterials for articulating implant applications can be found elsewhere .
Joint simulator tests: These tests are primarily developed for pre-clinical evaluation of overall tribological performance of new materials and implant designs combinations before their in vivo use. In these tests along with materials the full size design of implants are tested under clinically relevant loading and kinematic conditions. The machines are designed to simulate physiological conditions that prevail in vivo and therefore, can predict tribological performance of total joint replacement (TJR) prostheses. Further, these machines are currently being used as research tools to determine the influence different variables such as surface roughness [81,82], design changes , microseparation , kinematic and loading conditions [82,85-87]. Typical loading and movement profiles of knee joint simulator are shown in Fig. 9. During last two decades there has been significant increase in the use of joint simulators and therefore, simulators with different capabilities such as degrees of freedom, number of stations, position of implant components, lubrication and its temperature control, are currently available [21,88]. Some of the important hip and knee joint simulators and their characteristics are summarized elsewhere [21,88].
The wear debris characteristics such as size, volume, shape and composition found to strongly influence the osteolysis and tissue reactions in THA and TKA . Several parameters thought to influence the debris characteristics including articulating pair, implant design, loading characteristics, and type of testing. For example, wear the particles extracted from hip joint simulator testing were significantly smaller than those obtained in sliding wear testing  and is primarily due to variations in contact geometry, loadings and movements. Similarly, hip joint simulator testing of UHMWPE on zirconia ceramic, metal-on-metal and alumina ceramic-on-ceramic articulations showed significantly larger wear particles of UHMWPE than metal and ceramic wear particles . Dowson et al.  provided wear data supporting the idea that larger femoral head diameter and smallest diameteral clearances resulted in mixed lubrication leading to low wear rates of metal-on-metal hip implants in joint wear simulator. For realistic estimation of wear performance of different implant designs and materials joint simulators appears to provide best option. A more detailed review on joint simulator studies performed on bulk ceramics and surface modified articulating biomaterials can be found in reference .
Although joint simulators can simulate in vivo loading and movements, the wear rates determined using different simulators do not match . The results clearly demonstrated the tribological behavior of same implant designs and materials derived from different joint simulators cannot be directly comparable. The discrepancy could be primarily due to variations in test protocols among the researchers. For example hip joint simulators with upright position of the prosthesis can generate higher maximum temperatures, than upside-down position, leading to excessive/ faster tribofilm formation this producing low wear rates due to better lubrication . Knee joint simulators are now available with a facility to perform simulation in either force control or displacement control per ISO 14243. It has been observed that the medial and lateral wear rate in force control testing was an order of magnitude (7.38 [+ or -] 1.18 mg/Mc) more than that observed with displacement control testing (0.6 mg/Mc) . Therefore, the control mode during simulator testing of total knee prosthesis can change the overall wear rate and scar size as well . DesJardins et al.  compared the treadmill walking kinematics (of patients with well function total knee replacements) with force controlled knee joint simulator kinematics using identical implant designs. Both showed similar contact pathways, motions and wear travel per cycle and it was concluded that force controlled testing can accurately reproduce the in vivo walking cycle of knee prosthesis. Similar variations have been observed in hip joint simulation due to application of more simplified loading profiles [57,76]. Finally maintaining proper lubrication during testing via accurate temperature control, thereby avoiding protein denaturing and maintaining proper concentration of the same in the test fluid, is also extremely important to achieve reliable wear rates in joint simulators . In summary, efforts are essential to standardize the joint simulation testing conditions so that comparable wear rates can be achieved on new materials and designs testing using different simulators .
The total degradation of artificial implants consists of degradation due to simultaneous influence of mechanical wear, chemical degradation (corrosion) and their synergy. The degradation due to simultaneous influence of wear and corrosion is known as tribocorrosion [97-99]. It has been found that the degradation will be accelerated due to synergy between mechanical and corrosion related materials removal and the degradation is always more severe than individual effects of wear and corrosion [100,101]. The dominant contribution of wear or corrosion towards overall materials loss can be estimated from ratio of material loss due to corrosion (Wc) and wear (Ww) . It was proposed that mechanical wear, wear enhanced corrosion, corrosion enhanced wear and pure corrosion mechanisms dominate when Wc/Ww is < 0.1, 0.1-1.0, 1.0-10 and > 10, respectively . Tribocorrosion can occur under different wear conditions described earlier (Figs. 2 to 5). Tribocorrosion is highly complex degradation process that depends on several factors  including (a) materials properties--microstructure, hardness, oxide films, passivation tendency, wear debris, ductility, (b) wear test conditions contact stress, contact area/geometry, sliding velocity, type of movement, (c) electrochemical conditions--potential, passivation kinetics, reaction film/layer growth, dissolution, valence, and (d) solution/ electrolyte--pH, temperature, conductivity, viscosity, dissolved gases. The tribocorrosion in biomedical applications is often referred as "bio-tribocorrosion" and recent review on tribocorrosion  studies revealed that more than 60% of them are focused on biomedical applications, which clearly demonstrate the importance of bio-tribocorrosion. The critical regions of total hip replacements and dental implants susceptible to tribocorrosion are shown in Fig. 10.
The clinical consequences of tribocorrosion include complete mechanical failures [106-109], swelling and pain [103,110], painful local and systemic biological reactions [111,112], excessive metal ion release [113,114], bone loss [106,111], and others [106,107]. Therefore, tribocorrosion testing of materials for biomedical applications is very essential. Typically the tribological and electrochemical parameters must be controlled and recorded during tribocorrosion testing, using a tribometer and potentiostat/glavanostat. Typical tribocorrosion testing system, Fig. 11a, consists of electrochemical system connected to the wear test setup shown in Fig. 7. The test sample act as working electrode and counter material is insulated from the electrochemical system. Different types of reference and counter electrodes can be used. Tribocorrosion testing is relatively complex and involves controlling several tribological and electrochemical parameters as shown in Fig. 11b.
Recently, different tests methods have been developed [104,115-117] to evaluate tribocorrosion properties of materials. In one method, open circuit potential (OCP) is continuously monitored (chronopotentiometric) before, during and after wear testing. The increase in the corrosion tendency is generally indicated by drop in OCP to more cathodic values. The second method uses potentiostatic polarization where the potential is controlled throughout the tests to understand the response of contact zone under different oxidizing conditions. In this test, evolution of current is monitored during the wear tests where increase in the corrosion degradation is manifested as increase in the measured anodic current . Similarly, electrochemical impedance spectroscopy (EIS) can also be used to understand the tribocorrosion events . Typical tribocorrosion test protocol with EIS measurement is shown in Fig. 12.
The material loss can be estimated using gravimetric methods, metrological methods (from wear track measurements) and chemical methods for metal ion released in to the electrolyte. However, it is important to note that total materials loss (Wt) during tribocorrosion is not simple sum of material loss due to pure corrosion (Wc) and pure mechanical wear (Wm). The total material loss due to tribocorrosion is generally expressed as: Wt = Wm + Wc + Ws, where Ws is the synergetic effect of wear and corrosion, which can contribute between 20 and 70% of total material loss [103,105,115,116,119-125]. The 'Wt' can be calculated using experimentally measured wear track dimensions, pure mechanical wear testing estimates the 'Wm' and similarly from electrochemical measurements the 'Wc" can be calculated. More detailed description of estimation of synergy between corrosion wear and wear has been provided in "ASTM G119 - 09: Standard guide for determining synergism between wear and corrosion". More detailed methodology to understand the mechanism of passive film destruction, its reformation and kinetics during tribocorrosion has also been proposed recently [117,126,127], where tests will be performed in three stages namely, fully passive, partially active and fully active states of material, as shown in Fig. 12b. In this test the synergetic effect of corrosion and wear considers the influence of repeated passive layer destruction and formation during wear testing.
Several investigators evaluated the tribocorrosion performance of materials for biomedical applications under different test conditions and obtained very different results [56,103,105,119-121,128,129]. Further, mapping of different mechanisms such as micro-abrasion, corrosion, and material loss and synergetic effect, has also been attempted [130-132]. Tribocorrosion of CoCrMo alloys has been evaluated using instrumented hip joint simulators [133-135] and it was observed that wear induced corrosion contribute up to 87% and corrosion induced wear contribute up to 12% towards total material loss . One interesting observation was that the severity of tribocorrosion was relatively less in joint simulator testing compared to standard tribometer tests and is presumably due to better lubrication and contact area in the joint simulator tests . However, no studies have been reported on tribocorrosion using random or multi-directional tribometers and articulating systems such as metal-on-metal, UHMWPE-on-ceramic and ceramicon-ceramic.
The continuous increase in the younger population receiving load bearing implants such as hip and knee would increase the stresses on current implant materials and therefore the demand for newer materials with enhanced wear and corrosion properties continue to increase in the future. To qualify new materials and bearing couples, testing methods that closely replicate the service conditions must be developed. For this purpose recently multidirectional and random movement tribometers have been designed and developed. Although joint simulators provide more realistic test conditions compared to the standard tribological test machines, lack of standard test conditions among different research group preclude comparison of the tribological data generated by them on identical implant systems. Finally, integration of tribocorrosion evaluation in existing testing machines would simulate clinically relevant environments, loading and movements leading better understanding of tribological and electrochemical behavior, and their synergy in artificial load bearing implants.
[1.] S.H. Teoh, Fatigue of biomaterials: A review, Int. J. Fatigue. 22, 825-837 (2000).
[2.] D.W. Hoeppner, V. Chandrasekaran, Fretting in orthopaedic implants: A review, Wear. 173, 189-197 (1994).
[3.] M.N. Rahaman, A. Yao, B.S. Bal, J.P. Garino, M.D. Ries, Ceramics for prosthetic hip and knee joint replacement, J. Am. Ceram. Soc. 90, 1965-1988 (2007).
[4.] K.D. Mimnaugh, J.Q. Yao, M.P. Laurent, R. Crowninshield, J.J. Mason, C. Blanchard, The Effect of Entrapped Bone Particles on the Surface Morphology and Wear of Polyethylene, J. Arthroplasty. 24, 303-309 (2009).
[5.] S.M. Kurtz, W. Hozack, M. Marcolongo, J. Turner, C. Rimnac, A. Edidin, Degradation of mechanical properties of UHMWPE acetabular liners following long-term implantation, J. Arthroplasty. 18, 68-78 (2003).
[6.] M.K. Musib, Response to Ultra-high Molecular Weight Polyethylene Particles, Am. J. Biomed. Eng. 1, 7-12 (2011).
[7.] V.K. Balla, M. Das, S. Datta, B. Kundu, Articulating Biomaterials: Surface Engineering, Tribology, and Biocompatibility, in: R. Tyagi, J.P. Davim (Eds.), Process. Tech. Tribol. Behav. Compos. Mater., IGI Global, pp. 218-267 (2015).
[8.] A. Buford, T. Goswami, Review of wear mechanisms in hip implants: Paper I--General, Mater. Des. 25, 385-393 (2004).
[9.] T.P. Schmalzried, J.J. Callaghan, Current Concepts Review Wear in Total Hip and Knee Replacements, J. Bone Jt. Surg. 81A, 115-136 (1999).
[10.] R.A. Cooper, C.M. McAllister, L.S. Borden, T.W. Bauer, Polyethylene debris-induced osteolysis and loosening in uncemented total hip arthroplasty. A cause of late failure, J. Arthroplasty. 7, 285-290 (1992).
[11.] A.A. Edidin, C.M. Rimnac, V.M. Goldberg, S.M. Kurtz, Mechanical behavior, wear surface morphology, and clinical performance of UHMWPE acetabular components after 10 years of implantation, Wear. 250-251, 152-158 (2001).
[12.] G.J. Atkins, D.R. Haynes, D.W. Howie, D.M. Findlay, Role of polyethylene particles in peri-prosthetic osteolysis: A review, World J Orthop. 2, 93-101 (2011).
[13.] M.A. McGee, D.W. Howie, K. Costi, D.R. Haynes, C.I. Wildenauer, M.J. Pearcy, et al., Implant retrieval studies of the wear and loosening of prosthetic joints: A review, Wear. 241, 158-165 (2000).
[14.] K. Hirakawa, J.J. Jacobs, R. Urban, T. Saito, Mechanisms of failure of total hip replacements: lessons learned from retrieval studies., Clin. Orthop. Relat. Res. 420, 10-17 (2004).
[15.] V. Sansone, D. Pagani, M. Melato, The effects on bone cells of metal ions released from orthopaedic implants. A review., Clin. Cases Miner. Bone Metab. 10, 34-40 (2013).
[16.] N.J. Hallab, J.J. Jacobs, Biologic effects of implant debris., Bull. NYU Hosp. Jt. Dis. 67, 182-188 (2009).
[17.] M. Slonaker, T. Goswami, Review of wear mechanisms in hip implants: Paper II--ceramics IG004712, Mater. Des. 25, 395-405 (2004).
[18.] J.J. Callaghan, D.R. Pedersen, J.P. Olejniczak, D.D. Goetz, R.C. Johnston, Radiographic measurement of wear in 5 cohorts of patients observed for 5 to 22 years., Clin. Orthop. Relat. Res. 317, 14-18 (1995).
[19.] S.M. Jones, I.M. Pinder, C.G. Moran, A.J. Malcolm, Polyethylene wear in uncemented knee replacements, J Bone Jt. Surg Br. 74, 18-22 (1992).
[20.] a V Lombardi, T.H. Mallory, B.K. Vaughn, P. Drouillard, Aseptic loosening in total hip arthroplasty secondary to osteolysis induced by wear debris from titanium-alloy modular femoral heads., J. Bone Joint Surg. Am. 71, 1337-1342 (1989).
[21.] S. Affatato, M. Spinelli, M. Zavalloni, C. Mazzega-Fabbro, M. Viceconti, Tribology and total hip joint replacement: Current concepts in mechanical simulation, Med. Eng. Phys. 30, 1305-1317 (2008).
[22.] S. Affatato, D. Brando, Wear of Orthopaedic Implants and Artificial Joints, in: Wear Orthop. Implant. Artif. Joints, Elsevier, pp. 3-26 (2013).
[23.] S.S. Santavirta, R. Lappalainen, P. Pekko, A. Anttila, Y.T. Konttinen, The counterface, surface smoothness, tolerances, and coatings in total joint prostheses., Clin. Orthop. Relat. Res. 369, 92-102 (1999).
[24.] C. Klapperich, J. Graham, L. Pruitt, M.D. Ries, Failure of a metal-on-metal total hip arthroplasty from progressive osteolysis, J. Arthroplasty. 14, 877-881 (1999).
[25.] S.T. O'Brien, C.D. Burnell, D.R. Hedden, J.-M. Brandt, Abrasive wear and metallosis associated with cross-linked polyethylene in total hip arthroplasty., J. Arthroplasty. 28, 197.e17-21 (2013).
[26.] S. Ge, S. Wang, N. Gitis, M. Vinogradov, J. Xiao, Wear behavior and wear debris distribution of UHMWPE against Si3N4 ball in bi-directional sliding, Wear. 264, 571-578 (2008).
[27.] M.P. Gispert, A.P. Serro, R. Colaco, B. Saramago, Friction and wear mechanisms in hip prosthesis: Comparison of joint materials behaviour in several lubricants, Wear. 260, 149-158 (2006).
[28.] D. Gundapaneni, R.T. Laughlin, T. Goswami, Characterization of retrieved total ankle replacement liners, Eng. Fail. Anal. 70, 237-254 (2016).
[29.] S. Wang, J. Song, Z. Liao, P. Feng, W. Liu, Comparison of wear behaviors for an artificial cervical disc under flexion/ extension and axial rotation motions, Mater. Sci. Eng. C. 63, 256-265 (2016).
[30.] J. Pellier, J. Geringer, B. Forest, Fretting-corrosion between 316L SS and PMMA: Influence of ionic strength, protein and electrochemical conditions on material wear. Application to orthopaedic implants, Wear. 271, 1563-1571 (2011).
[31.] Z.B. Cai, G.A. Zhang, Y.K. Zhu, M.X. Shen, L.P. Wang, M.H. Zhu, Torsional fretting wear of a biomedical Ti6Al7Nb alloy for nitrogen ion implantation in bovine serum, Tribol. Int. 59, 312-320 (2013).
[32.] S. Kerwell, M. Alfaro, R. Pourzal, H.J. Lundberg, Y. Liao, C. Sukotjo, et al., Examination of failed retrieved temporomandibular joint (TMJ) implants, Acta Biomater. 32, 324-335 (2016).
[33.] V.G. Pina, V. Amig??, A.I. Mu??oz, Microstructural, electrochemical and tribo-electrochemical characterisation of titanium-copper biomedical alloys, Corros. Sci. 109, 115125 (2016).
[34.] A. Wang, V.K. Polineni, C. Stark, J.H. Dumbleton, Effect of femoral head surface roughness on the wear of ultrahigh molecular weight polyethylene acetabular cups, J. Arthroplasty. 13, 615-620 (1998).
[35.] A. Turger, J. Kohler, B. Denkena, T. a Correa, C. Becher, C. Hurschler, Manufacturing conditioned roughness and wear of biomedical oxide ceramics for all-ceramic knee implants., Biomed. Eng. Online. 12, 84 (2013).
[36.] P. Huang, A. Salinas-Rodriguez, H.F. Lopez, Tribological behaviour of cast and wrought Co-Cr-Mo implant alloys, Mater. Sci. Technol. 15, 1324-1330 (1999).
[37.] A. Wang, A. Essner, Three-body wear of UHMWPE acetabular cups by PMMA particles against CoCr, alumina and zirconia heads in a hip joint simulator, Wear. 250-251, 212-216 (2001).
[38.] J. Livermore, D. Ilstrup, B. Morrey, Effect of femoral head size on wear of the polyethylene acetabular component., J. Bone Joint Surg. Am. 72, 518-28 (1990).
[39.] P.F. Lachiewicz, D.S. Heckman, E.S. Soileau, J. Mangla, J.M. Martell, Femoral head size and wear of highly cross-linked polyethylene at 5 to 8 years, Clin Orthop Relat Res. 467, 3290-3296 (2009).
[40.] D. Dowson, S. Taheri, N.C. Wallbridge, The role of counterface imperfections in the wear of polyethylene, Wear. 119, 277-293 (1987).
[41.] J. Fisher, P. Firkins, E.A. Reeves, J.L. Hailey, G.H. Isaac, The influence of scratches to metallic counterfaces on the wear of ultra-high molecular weight polyethylene., Proc. Inst. Mech. Eng. H. 209, 263-264 (1995).
[42.] K. Kato, Wear in relation to friction--A review, Wear. 241, 151-157 (2000).
[43.] E. a Vogler, Structure and reactivity of water at biomaterial surfaces., Adv. Colloid Interface Sci. 74, 69-117 (1998).
[44.] Z. Pawlak, A.D. Petelska, W. Urbaniak, K.Q. Yusuf, A. Oloyede,
Relationship Between Wettability and Lubrication Characteristics of the Surfaces of Contacting Phospholipid-Based Membranes, Cell Biochem. Biophys. 65, 335-345 (2013).
[45.] M.R. Widmer, M. Heuberger, J. Voros, N.D. Spencer, Influence of polymer surface chemistry on frictional properties under protein-lubrication conditions: Implications for hip-implant design, Tribol. Lett. 10, 111-116 (2001).
[46.] Z. Pawlak, W. Urbaniak, A. Oloyede, The relationship between friction and wettability in aqueous environment, Wear. 271, 1745-1749 (2011).
[47.] R.S. Gates, M. Hsu, E.E. Klaus, Tribochemical Mechanism of Alumina With Water, Tribol. Trans. 32, 357-363 (1989).
[48.] V.K. Balla, W. Xue, S. Bose, A. Bandyopadhyay, Laser-assisted Zr/ZrO2 coating on Ti for load-bearing implants, Acta Biomater. 5, 2800-2809 (2009).
[49.] S. Bodhak, V.K. Balla, S. Bose, A. Bandyopadhyay, U. Kashalikar, S.K. Jha, et al., In vitro biological and tribological properties of transparent magnesium aluminate (Spinel) and aluminum oxynitride (ALON), J. Mater. Sci. Mater. Med. 22, 1511-1519 (2011).
[50.] D. Xiong, Z. Gao, Z. Jin, Friction and wear properties of UHMWPE against ion implanted titanium alloy, Surf. Coatings Technol. 201, 6847-6850 (2007).
[51.] A. Unsworth, The effects of lubrication in hip prostheses, Phys. Med. Biol. 23, 253-268 (1978).
[52.] J. Black, Orthopaedic Biomaterials in Research and Practice, Churchill Livingstone, 1988.
[53.] S.C. Scholes, A. Unsworth, Comparison of friction and lubrication of different hip prostheses., Proc. Inst. Mech. Eng. H. 214, 49-57 (2000).
[54.] M. Hussein, A. Mohammed, N. Al-Aqeeli, Wear Characteristics of Metallic Biomaterials: A Review, Materials (Basel). 8, 2749-2768 (2015).
[55.] Z.-R. Zhou, H.-Y. Yu, J. Zheng, L.-M. Qian, Y. Yan, Explains the relationship between structures and tribological properties of human teeth, in: Dent. Biotribology, Springer Science & Business Media, p. 177 (2013).
[56.] D. Holmes, S. Sharifi, M.M. Stack, Tribo-corrosion of steel in artificial saliva, Tribol. Int. 75, 80-86 (2014).
[57.] V. Saikko, T. Ahlroos, Type of motion and lubricant in wear simulation of polyethylene acetabular cup., Proc. Inst. Mech. Eng. H. 213, 301-310 (1999).
[58.] A. Wang, V.K. Polineni, A. Essner, M. Sokol, D.C. Sun, C. Stark, et al., The significance of nonlinear motion in the wear screening of orthopaedic implant materials, J. Test. Eval. 25, 239-245 (1997).
[59.] V. Saikko, A multidirectional motion pin-on-disk wear test method for prosthetic joint materials, J. Biomed. Mater. Res. 41, 58-64 (1998).
[60.] H. McKellop, I.C. Clarke, K.L. Markolf, H.C. Amstutz, Wear characteristics of UHMW polyethylene: a method for accurately measuring extremely low wear rates., J. Biomed. Mater. Res. 12, 895-927 (1978).
[61.] W. Rostoker, J.O. Galante, Contact pressure dependence of wear rates of ultra high molecular weight polyethylene., J. Biomed. Mater. Res. 13, 957-64 (1979).
[62.] C.R. Bragdon, D.O. O'Connor, J.D. Lowenstein, M. Jasty, S. a Biggs, W.H. Harris, A new pin-on-disk wear testing method for simulating wear of polyethylene on cobalt-chrome alloy in total hip arthroplasty., J. Arthroplasty. 16, 658-665 (2001).
[63.] M.E. Turell, G.E. Friedlaender, A. Wang, T.S. Thornhill, A. Bellare, The effect of counterface roughness on the wear of UHMWPE for rectangular wear paths, Wear. 259, 984-991 (2005).
[64.] D. Baykal, R.S. Siskey, H. Haider, V. Saikko, T. Ahlroos, S.M. Kurtz, Advances in tribological testing of artificial joint biomaterials using multidirectional pin-on-disk testers, J. Mech. Behav. Biomed. Mater. 31, 117-134 (2014).
[65.] D. Mazzucco, M. Spector, Effects of contact area and stress on the volumetric wear of ultrahigh molecular weight polyethylene, Wear. 254, 514-522 (2003).
[66.] D. Mazzucco, M. Spector, Contact area as a critical determinant in the tribology of metal-on-polyethylene total joint arthroplasty, J. Tribol. Asme. 128, 113-121 (2006).
[67.] J. Charnley, The wear of plastic materials in the hip-joint, Plast. Rubber Inst. 1, 59-63 (1976).
[68.] C.R. Bragdon, D.O. O'Connor, J.D. Lowenstein, M. Jasty, W.D. Syniuta, The importance of multidirectional motion on the wear of polyethylene., Proc. Inst. Mech. Eng. H. 210, 157-165 (1996).
[69.] V. Saikko, J. Kostamo, RandomPOD-A new method and device for advanced wear simulation of orthopaedic biomaterials, J. Biomech. 44, 810-814 (2011).
[70.] S. Sathasivam, P.S. Walker, P.A. Campbell, K. Rayner, The effect of contact area on wear in relation to fixed bearing and mobile bearing knee replacements., J. Biomed. Mater. Res. 58, 282-290 (2001).
[71.] M. Turell, A. Wang, A. Bellare, Quantification of the effect of cross-path motion on the wear rate of ultra-high molecular weight polyethylene, Wear. 255, 1034-1039 (2003).
[72.] V. Saikko, T. Ahlroos, Wear simulation of UHMWPE for total hip replacement with a multidirectional motion pin-on-disk device: Effects of counterface material, contact area, and lubricant, J. Biomed. Mater. Res. 49, 147-154 (2000).
[73.] E.S. Greenbaum, B.B. Burroughs, W.H. Harris, O.K. Muratoglu, Effect of lipid absorption on wear and compressive properties of unirradiated and highly crosslinked UHMWPE: an in vitro experimental model., Biomaterials. 25, 4479-4484 (2004).
[74.] V. Saikko, J. Keranen, Wear Simulation of Alumina-on-Alumina Prosthetic Hip Joints Using a Multidirectional Motion Pin-on-Disk Device, J. Am. Ceram. Soc. 85, 2785-2791 (2002).
[75.] V. Saikko, O. Calonius, J. Keranen, Effect of slide track shape on the wear of ultra-high molecular weight polyethylene in a pin-on-disk wear simulation of total hip prosthesis., J. Biomed. Mater. Res. B. Appl. Biomater. 69, 141-148 (2004).
[76.] V. Saikko, O. Calonius, Slide track analysis of the relative motion between femoral head and acetabular cup in walking and in hip simulators., J. Biomech. 35, 455-464 (2002).
[77.] O. Calonius, V. Saikko, Slide track analysis of eight contemporary hip simulator designs., J. Biomech. 35, 1439-1450 (2002).
[78.] D. Bennett, J.F. Orr, D.E. Beverland, R. Baker, The influence of shape and sliding distance of femoral head movement loci on the wear of acetabular cups in total hip arthroplasty., Proc. Inst. Mech. Eng. H. 216, 393-402 (2002).
[79.] V. Saikko, J. Kostamo, Performance analysis of the RandomPOD wear test system, Wear. 297, 731-735 (2013).
[80.] V. Saikko, In vitro wear simulation on the RandomPOD wear testing system as a screening method for bearing materials intended for total knee arthroplasty, J. Biomech. 47, 2774-2778 (2014).
[81.] J.D. DesJardins, B. Burnikel, M. LaBerge, UHMWPE wear against roughened oxidized zirconium and CoCr femoral knee components during force-controlled simulation, Wear. 264, 245-256 (2008).
[82.] A.P.D. Elfick, S.L. Smith, S.M. Green, A. Unsworth, The quantitative assessment of UHMWPE wear debris produced in hip simulator testing: The influence of head material and roughness, motion and loading, Wear. 249, 517-527 (2001).
[83.] a Galvin, L.M. Jennings, H.M. McEwen, J. Fisher, The influence of tibial tray design on the wear of fixed-bearing total knee replacements., Proc. Inst. Mech. Eng. H. 222, 1289-1293 (2008).
[84.] J.A. Ortega-Saenz, M.A.L. Hernandez-Rodriguez, A. Perez-Unzueta, R. Mercado-Solis, Development of a hip wear simulation rig including micro-separation, Wear. 263, 1527-1532 (2007).
[85.] J.D. DesJardins, S.A. Banks, L.C. Benson, T. Pace, M. LaBerge, A direct comparison of patient and force-controlled simulator total knee replacement kinematics, J. Biomech. 40, 3458-3466 (2007).
[86.] P.I. Barnett, J. Fisher, D.D. Auger, M.H. Stone, E. Ingham, Comparison of wear in a total knee replacement under different kinematic conditions, J. Mater. Sci. Mater. Med. 12, 1039-1042 (2001).
[87.] K.A. Ezzet, J.C. Hermida, N. Steklov, D.D. D' Lima, Wear of Polyethylene Against Oxidized Zirconium Femoral Components. Effect of Aggressive Kinematic Conditions and Malalignment in Total Knee Arthroplasty, J. Arthroplasty. 27, 116-121 (2012).
[88.] M.Z. S. Affatato, W. Leardini, Hip Joint Simulators: State of the Art, in: D.M. Benazzo F., Falez F. (Ed.), Bioceram. Altern. Bear. Jt. Arthroplast., pp. 171-180 (2006).
[89.] I.M. Punt, S. Austen, J.P.M. Cleutjens, S.M. Kurtz, R.H.M. ten Broeke, L.W. van Rhijn, et al., Are periprosthetic tissue reactions observed after revision of total disc replacement comparable to the reactions observed after total hip or knee revision surgery?, Spine (Phila. Pa. 1976). 37, 150-159 (2012).
[90.] R. Pourzal, I. Catelas, R. Theissmann, C. Kaddick, A. Fischer, Characterization of wear particles generated from CoCrMo alloy under sliding wear conditions, Wear. 271, 1658-1666 (2011).
[91.] J.L. Tipper, P.J. Firkins, A.A. Besong, P.S.M. Barbour, J. Nevelos, M.H. Stone, et al., Characterisation of wear debris from UHMWPE on zirconia ceramic, metal-on-metal and alumina ceramic-on-ceramic hip prostheses generated in a physiological anatomical hip joint simulator, Wear. 250-251, 120-128 (2001).
[92.] D. Dowson, C. Hardaker, M. Flett, G.H. Isaac, A hip joint simulator study of the performance of metal-on-metal joints: Part II: Design, J. Arthroplasty. 19, 124-130 (2004).
[93.] Z. Lu, H. McKellop, P. Liao, P. Benya, Potential thermal artifacts in hip joint wear simulators, J. Biomed. Mater. Res. 48, 458-464 (1999).
[94.] S. Affatato, Displacement or Force Control Knee Simulators? Variations in Kinematics and in Wear., Artif. Organs. 40, 195-201 (2016).
[95.] T. Schwenke, D. Orozco, E. Schneider, M.A. Wimmer, Differences in wear between load and displacement control tested total knee replacements, Wear. 267, 757-762 (2009).
[96.] S.S. Brown, I.C. Clarke, A Review of Lubrication Conditions for Wear Simulation in Artificial Hip Replacements, Tribol. Trans. 49, 72-78 (2006).
[97.] P. Jemmely, S. Mischler, D. Landolt, Tribocorrosion behaviour of Fe-17Cr stainless steel in acid and alkaline solutions, Tribol. Int. 32, 295-303 (1999).
[98.] D. Landolt, S. Mischler, M. Stemp, Electrochemical methods in tribocorrosion: A critical appraisal, Electrochim. Acta. 46, 3913-3929 (2001).
[99.] S. Mischler, P. Ponthiaux, A round robin on combined electrochemical and friction tests on alumina/stainless steel contacts in sulphuric acid, Wear. 248, 211-225 (2001).
[100.] A. Iwabuchi, J.W. Lee, M. Uchidate, Synergistic effect of fretting wear and sliding wear of Co-alloy and Ti-alloy in Hanks' solution, Wear. 263, 492-500 (2007).
[101.] J. Jiang, M.M. Stack, A. Neville, Modelling the tribo-corrosion interaction in aqueous sliding conditions, in: Tribol. Int., pp. 669-679 (2002).
[102.] M.M. Stack, G.H. Abdulrahman, Mapping erosion-corrosion of carbon steel in oil exploration conditions: Some new approaches to characterizing mechanisms and synergies, Tribol. Int. 43, 1268-1277 (2010).
[103.] M.T. Mathew, P. Srinivasa Pai, R. Pourzal, A. Fischer, M.A. Wimmer, Significance of tribocorrosion in biomedical applications: Overview and current status, Adv. Tribol. 2009, 250986 (2009).
[104.] S. Mischler, Triboelectrochemical techniques and interpretation methods in tribocorrosion: A comparative evaluation, Tribol. Int. 41, 573-583 (2008).
[105.] N. Diomidis, S. Mischler, N.S. More, M. Roy, Triboelectrochemical characterization of metallic biomaterials for total joint replacement, Acta Biomater. 8, 852-859 (2012).
[106.] J. Cohen, Current concepts review. Corrosion of metal orthopaedic implants., J. Bone Joint Surg. Am. 80, 1554 (1998).
[107.] J.J. Jacobs, N.J. Hallab, R.M. Urban, M. a Wimmer, Wear particles., J. Bone Joint Surg. Am. 88 Suppl 2, 99-102(2006).
[108.] P.M. Pellicci, E.A. Salvati, H.J. Robinson, Mechanical failures in total hip replacement requiring reoperation., J. Bone Joint Surg. Am. 61, 28-36 (1979).
[109.] M.N. Jolley, E.A. Salvati, G.C. Brown, Early results and complications of surface replacement of the hip., J. Bone Joint Surg. Am. 64, 366-377 (1982).
[110.] F.W. Chan, J.D. Bobyn, J.B. Medley, J.J. Krygier, M. Tanzer, The Otto Aufranc Award. Wear and lubrication of metal-on-metal hip implants., Clin. Orthop. Relat. Res. 369, 10-24 (1999).
[111.] R.M. Urban, J.J. Jacobs, M.J. Tomlinson, J. Gavrilovic, J. Black, M. Peoc'h, Dissemination of wear particles to the liver, spleen, and abdominal lymph nodes of patients with hip or knee replacement., J Bone Jt. Surg Am. 82-A, 457-476
[112.] U. Kamachimudali, T.M. Sridhar, B. Raj, Corrosion of bio implants, Sadhana. 28, 601-637 (2003).
[113.] K.J. Waldron, J.C. Rutherford, D. Ford, N.J. Robinson, Metalloproteins and metal sensing., Nature. 460, 823-830 (2009).
[114.] H.-G. Willert, G.H. Buchhorn, A. Fayyazi, R. Flury, M. Windler, G. Koster, et al., Metal-on-metal bearings and hypersensitivity in patients with artificial hip joints. A clinical and histomorphological study., J. Bone Joint Surg. Am. 87, 28-36 (2005).
[115.] M.T. Mathew, M.A. Wimmer, Tribocorrosion in artificial joints: in vitro testing and clinical implications, in: Y. Yan (Ed.), Bio-Tribocorrosion Biomater. Med. Implant., Elsevier, pp. 341-371 (2013).
[116.] P. Ponthiaux, R. Bayon, F. Wenger, J.-P. Celis, Testing protocol for the study of bio-tribocorrosion, in: Y. Yan (Ed.), Bio-Tribocorrosion Biomater. Med. Implant., Elsevier, pp. 372-394, (2013).
[117.] N. Diomidis, J.P. Celis, P. Ponthiaux, F. Wenger, A methodology for the assessment of the tribocorrosion of passivating metallic materials, Lubr. Sci. 21, 53-67 (2009).
[118.] M. Stemp, S. Mischler, D. Landolt, The effect of mechanical and electrochemical parameters on the tribocorrosion rate of stainless steel in sulphuric acid, Wear. 255, 466-475 (2003).
[119.] M.T. Mathew, M.J. Runa, M. Laurent, J.J. Jacobs, L.A. Rocha, M.A. Wimmer, Tribocorrosion behavior of CoCrMo alloy for hip prosthesis as a function of loads: A comparison between two testing systems, Wear. 271, 1210-1219 (2011).
[120.] J.P. Celis, P. Ponthiaux, F. Wenger, Tribo-corrosion of materials: Interplay between chemical, electrochemical, and mechanical reactivity of surfaces, Wear. 261, 939-946 (2006).
[121.] I. Hacisalihoglu, A. Samancioglu, F. Yildiz, G. Purcek, A. Alsaran, Tribocorrosion properties of different type titanium alloys in simulated body fluid, Wear. 332-333, 679-686 (2015).
[122.] T.C. Zhang, X.X. Jiang, S.Z. Li, X.C. Lu, A quantitative estimation of the synergy between corrosion and abrasion, Corros. Sci. 36, 1953-1962 (1994).
[123.] M.-H. Hong, S.-I. Pyun, Corrosive wear behaviour of 304-L stainless steel in 1 N H2SO4 solution part 2. Effect of chloride ion concentration, Wear. 147, 69-78 (1991).
[124.] K. Miyoshi, Studies of mechanochemical interactions in the tribological behavior of materials, Surf. Coatings Technol. 43-44, 799-812 (1990).
[125.] A.L. Grogan, V.H. Desai, F.C. Gray, S.L. Rice, Apparatus for chemomechanical wear studies with biaxial load and surface charge control, Wear. 152, 383-393 (1992).
[126.] I. Garcia, D. Drees, J.P Celis, Corrosion-wear of passivating materials in sliding contacts based on a concept of active wear track area, Wear. 249, 452-460 (2001).
[127.] N. Diomidis, J.P. Celis, P. Ponthiaux, F. Wenger, Tribocorrosion of stainless steel in sulfuric acid: Identification of corrosion-wear components and effect of contact area, Wear. 269, 93-103 (2010).
[128.] A.C. Fernandes, F. Vaz, E. Ariza, L.A. Rocha, A.R.L. Ribeiro, A.C. Vieira, et al., Tribocorrosion behaviour of plasma nitrided and plasma nitrided + oxidised Ti6Al4V alloy, Surf. Coatings Technol. 200, 6218-6224 (2006).
[129.] J. Geringer, D.D. Macdonald, Friction/fretting-corrosion mechanisms: Current trends and outlooks for implants, Mater. Lett. 134, 152-157 (2014).
[130.] M.M. Stack, W. Huang, G. Wang, C. Hodge, Some views on the construction of bio-tribo-corrosion maps for Titanium alloys in Hanks solution: Particle concentration and applied loads effects, Tribol. Int. 44, 1827-1837 (2011).
[131.] K. Sadiq, R.A. Black, M.M. Stack, Bio-tribocorrosion mechanisms in orthopaedic devices: Mapping the micro-abrasion-corrosion behaviour of a simulated CoCrMo hip replacement in calf serum solution, Wear. 316, 58-69 (2014).
[132.] K. Sadiq, M.M. Stack, R.A. Black, Wear mapping of CoCrMo alloy in simulated bio-tribocorrosion conditions of a hip prosthesis bearing in calf serum solution, Mater. Sci. Eng. C. 49, 452-462 (2015).
[133.] J. Hesketh, X. Hu, Y. Yan, D. Dowson, A. Neville, Biotribocorrosion: Some electrochemical observations from an instrumented hip joint simulator, Tribol. Int. 59, 332-338 (2013).
[134.] J. Hesketh, Q. Meng, D. Dowson, A. Neville, Biotribocorrosion of metal-on-metal hip replacements: How surface degradation can influence metal ion formation, Tribol. Int. 65, 128-137 (2013).
[135.] Y. Yan, A. Neville, J. Hesketh, D. Dowson, Real-time corrosion measurements to assess biotribocorrosion mechanisms with a hip simulator, Tribol. Int. 63, 115-122 (2013).
Vamsi Krishna Balla *, Mitun Das
Bioceramics & Coating Division, CSIR-Central Glass & Ceramic Research Institute (CSIR-CGCRI), 196 Raja S.C. Mullick Road, Kolkata 700 032, India.
Received 10 November 2017; Accepted 11 November 2017; Published online 31 December 2017
* Coresponding author: Dr. Vamsi Krishna Balia; firstname.lastname@example.org
Caption: Figure 1: Representative image of a retrieved hip (Reprinted with permission from [4,5]) and knee implant (Open access from ) liners
Caption: Figure 2: (a) Schematic diagram showing abrasive wear, (b) Typical abrasive wear surface morphology of CoCrMo alloy (Reprinted with permission from ), XPE (Reprinted with permission from ). XPE: highly-crosslinked polyethylene
Caption: Figure 3: (a) Schematic diagram showing adhesive wear mechanism, (b) Examples of adhesive wear in UHMWPE (Reprinted with permission from ), 316L stainless steel (Reprinted with permission from ) and [Al.sub.2][O.sub.3] ((Reprinted with permission from )
Caption: Figure 4: (a) Macroscopic and microscopic fatigue wear mechanism, (b) Examples of fatigue wear, (left) fracture and delamination of retrieved total ankle replacement liners (Reprinted with permission from ) (right) fatigue wear due to UHMWPE deformation in artificial cervical discs (Reprinted with permission from )
Caption: Figure 5: (a) Fretting wear mechanism, (b) (Left) Morphology of fretting wear in retrieved hip implant (Reprinted with permission from ) (Right) high magnification morphology of fretting wear in Ti6Al7Nb alloy (Reprinted with permission from )
Caption: Figure 6: Typical appearance of corrosion wear damage in (left) failed retrieved temporomandibular joint (Reprinted with permission from ) (right) tribocorrosion features on commercially pure Ti (Reprinted with permission from )
Caption: Figure 7: Popular wear screening test configurations. Ball & crater, twin disc and one-way slide testing configurations are often used for dental materials testing
Caption: Figure 8: State-of-the-art 16-station random pin-on-disc testing system (left) and typical random pin track after 2 min of sliding (right) (Reprinted with permission from )
Caption: Figure 9: Typical kinematic and loading profiles of knee joint simulators (FE: Flexion-Extension; TR: Tibial Rotation; AF: Axial Force; APD: Anterior-Posterior Displacement)
Caption: Figure 10: Areas susceptible to tribocorrosion in (a) artificial hip replacements (Reprinted with permission from ) (b) artificial dental implants (Open access from )
Caption: Figure 11: (a) Typical tribocorrosion test setup (adapted from ), CE: Counter electrode; RE: Reference electrode; WE: Working electrode; Fn: Normal load; F: Frequency; D: Displacement, (b) Basic steps involved in tribocorrosion evaluation (adapted from )
Caption: Figure 12: (a) Tribocorrosion test protocol for biomedical applications (adapted from ). PS, potentiostatic test; OCP, open-circuit potential test; EIS, spectroscopy. Cleaning: -0.9V vs SCE. (b) Three step tribocorrosion test (adapted from )
Table 1: Wear rate of UHMWPE under different test conditions in multi-directional pin-on-disc tester  Motion Load Wear rate ([10.sup.-6] [m.sup.3]/Nm) Circular Static 2.55 [+ or -] 0.31 Random 2.49 [+ or -] 0.51 Random Static 4.57 [+ or -] 0.37 Random 4.59 [+ or -] 0.30
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|Author:||Balla, Vamsi Krishna; Das, Mitun|
|Publication:||Trends in Biomaterials and Artificial Organs|
|Date:||Oct 1, 2017|
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