Abstract

Solution treatment and ageing (STA) is an effective strengthen-
ing method for aþ b titanium alloys. This paper reports the effect
of solution treatment and aging on the corrosion behaviour of Ti-
6Al-7Nb alloy in a simulated body fluid (Ringer’s solution). Ti-
6Al-7Nb alloy is hot rolled in the aþ bfield and subjected to solu-
tion treatment above and below its beta transus temperature
(1283 K). The solution treated specimens are water quenched
(WQ), air-cooled (AC), and furnace cooled (FC) at three different
rates, and subsequently aged at 823 K for 4 h. Microstructural
changes were examined using optical microscopy and phases devel-

oped were analyzed using XRD. The influence of microstructure on
the corrosion performance of the alloys are discussed in detail based
on the Open Circuit Potential (OCP), passive current density and
area of repassivation loop values obtained from the cyclic polariza-
tion study in Ringer’s solution. The passive current density was low
(0.5 lA/cm2) for the specimen with duplex microstructure obtained
for solution treated at 1223 K, air-cooled, and aged, in comparison
with that for as-rolled specimen (1.5 lA/cm2). The corrosion as-
pects resulting from various heat treatments are discussed in detail.

Abstract

The aim of this paper is to study the effect of Nþ ion implantation on corrosion and phase
formation on the implanted surfaces of Ti–6Al–4V and Ti–6Al–7Nb alloys. Nitrogen ion was
implanted on Ti–6Al–4V and Ti–6Al–7Nb alloys at an energy of 70 and 100 keV, respectively
using a 150 keV accelerator at different doses ranging from 5 1015 to 2.5 1017 ions/cm2.
Electrochemical studies have been carried out in Ringer
s solution in order to determine the
optimum dose that can give good corrosion resistance in a simulated body fluid condition. The
implanted surfaces of such modified doses were electrochemically passivated at 1.0 V for an
hour. Secondary ion mass spectroscopy was used to study and characterize titanium oxide and
titanium nitride layers produced on implanted surface and to correlate them with the corro-
sion resistance. The nature of the passive film of the implanted–passivated specimen was
compared with the unimplanted–passivated as well as as-implanted specimens.

Abstract

In the present investigation, surface modification of Ti–6Al–7Nb alloy with nitrogen ions is
considered as a method to improve its performance with respect to corrosion. Nitrogen ion
was implanted on Ti–6Al–7Nb alloy at an energy of 70 and 100 keV using a 150 keV accel-
erator at different doses between 1
1016 and 3
1017 ions/cm2. Gracing incidence X-ray
diffraction was employed on the implanted specimens to understand the phases formed with
increasing doses. The implanted samples were subjected to electrochemical study in Ringer’s
solution in order to determine the optimum dose that can give good corrosion resistance in a
simulated body fluid condition. The OCP of the implanted specimens were found to shift in
the noble direction in comparison with unimplanted specimen. The passive current density and
area of the repassivation loop were found to decrease as the dose values increased. The
electrochemical impedance spectroscopic results indicate that the polarization resistance was
higher for the dose of 2:5
1017 ions/cm2 implanted at both energy of 70 and 100 keV. Ni-
trogen ion implantation enhanced the passivability and reduces the corrosion kinetics of the
alloy surface with increasing tendency for repassivation. Nature of the surface and reason for
the variation and improvement in corrosion resistance are discussed in detail.
2002 Elsevier
Science Ltd. All rights reserved.

Abstract

A Ti – 6Al – 7Nb alloy was surface modiŽ ed using
pulsed plasma nitriding and nitrogen ion implantation
in order to study its microstructural changes and
corrosion performance. Pulsed plasma nitriding was
performed for 30 h at 913 K in a gas mixture of 3 : 1
N2 : H2 under a total pressure of 3 mbar. Nitrogen ion
was implanted at 100 keV using a 150 keV accelerator
at a dose of 2.561017 ions cm2. Gracing incidence
X-ray diffraction was employed to explore the phases
formed after treatments. To characterise the nature of
the modiŽ ed layers produced and to correlate with the
corrosion behaviour, SIMS was used. The samples were
subjected to electrochemical studies, namely, open
circuit potential (OCP) – time measurements and
potentiodynamic cyclic polarisation in a simulated
body  uid (Ringer’s solution). The OCP of the pulsed
plasma nitrided and Nz implanted samples were found
to shift towards the noble direction (2189 mVSCE and
282 mVSCE, respectively) in comparison with the
untreated sample (2338 mVSCE). The passivation
current density and area of the repassivation loop were
found to decrease for both treatments compared with
those in the untreated condition. Nitrogen ion implan-
tation enhanced the passivability and reduced the

corrosion kinetics of the alloy with increasing tendency
for repassivation. It shows very low passivation current
density compared with pulsed plasma nitriding (0.086
and 0.493 mA cm2, respectively). The nature of the modi-
Ž ed surfaces and the reason for the variation andimprove-
ment in corrosion resistance are discussed.

Abstract
The study involves mechanical deformation and heat treatment effect on
the microstructure of the Ti-6Al-7Nb alloy which is used as surgical implanted
materials. The observed properties of (alpha-beta) Ti-based alloy are strongly
dependent on their microstructures. These alloys are heat treated by solution
treatment and aging (STA) as an effective strengthening method for (alpha-
beta) titanium alloys.   
 Ti-6Al-7Nb alloy is hot rolled in the (alpha-beta) field and subjected
to solution treatment above and below its beta transformation temperature.
The solution treatments are applied at three different temperatures (850oC,
930oC and 950oC) for one hour to these treatments. The solution treatment
specimens are water quenched (WQ), normalizing [air cooled (AC) and
annealed,[ furnace cooled(FC)] and subsequently aged the quenched and
normalized specimens at 550oC for 4 hours.  
 Changes in the microstructure were observed from heat treatment
action using optical microscopy, Atomic Absorption Spectroscopy (AAS)   and
phases   analysis by X-ray diffraction (XRD). The microstructure examination
results for as received alloy indicate alpha grains within a b- transformed
matrix. The results also indicate that the grain size and percent of a /b for the
heat treated specimens depend on heat treatment type and cooling media. The
microstructure of specimens heat treated at 950oC with air cooled shows fine
duplex (a /b) structures which have excellent properties for surgical
implanted field applications.

ABSTRACT
Background: The clinical success of implants has been achieved not only because of the mechanical strength or
excellent biocompatibility of the implant material but also because of other characteristics such as surface
properties. In am attempt to modify the surface properties of an implant, this study was conducted to evaluate the
effect of biomimetic calcium phosphate coating on the bone-implant interface of screw-shaped implants made
from the commercially pure titanium and Ti-6Al-7Nb alloy by histological analysis with optical microscope.
Materials and methods: The screws were biomimetically coated with calcium phosphate by immersion in a
concentrated simulated body fluid (5 times), which simulates the inorganic part of human blood plasma, under static
conditions in a biological thermostat at 37oC for 6 days. The uncoated screws were passivated with 28% nitric acid.
The tibias of 15 white New Zealand rabbits were chosen as implantation sites for 4 implants (two from each material,
one is uncoated and the other is biomimetically coated). After 2, 6, and 18 weeks of healing period, 5 rabbits were
sacrificed for each period. The influence of modified surface on the bone-implant interaction was analyzed by
histological testing with optical microscope.
Results: The results obtained from this experiment revealed that the quality of bone response was improved among
the coated screws. Furthermore, the coated Ti-6Al-7Nb alloy implants had better properties than the coated
commercially pure titanium implants.
Conclusion: Biomimetic coatings play an active role in the bone-remodeling process by creating a friendly surface
for cell adhesion and proliferation, which is a key issue for bone regeneration.
Key words: Dental implant, bone-implant interface, biomimetic coating, Ti-6Al-7Nb alloy. (J Bagh Coll Dentistry 2008;
20(2):59-66)
 

Abstract

This paper compares the results of the effects of a biomimetic coating and electrophoretic
deposition (EPD) of hydroxyapatite (HA) on the bond strength between the bone, implant and cell
compatibility of Ti–6Al–7Nb dental implants. In the biomimetic process, screw shaped implants
were chemically etched and NaOH activated to form hydroxycarbonated apatite after they were
soaked for six days in a solution that was five times more concentrated than regular simulated
body fluid (SBF). Electrophoretic deposition was also used to obtain a uniform coating of HA on
other batchs of screws. Elemental, structural and in vivo histological and biomechanical
investigations were carried out on the modified surfaces of the screws. The results show that there
was a faster reaction of bone towards the coated implants compared to the uncoated one. More
mature bones were observed on HA coated implants and increased mechanical strength (torque
value) of bone–implant interface. Higher torque was needed to remove elephoretically and
biomimetically HA coated screws from its bed compared to that needed for uncoated one
(5550?16 and 37?45 N cm respectively). Biomimetic and electrophoretic coating with a bioactive
HA leads to high integration between bone and implant by increasing the bioactivity of the
product and to promoting mechanical properties of the implanted screws and enhanced
osseointegration during the healing period. Owing to the higher roughness and porosity of the
EPD coated screws (average Ra52921¡100 nm), the bone growth was much higher than that
coated biomimetically (average Ra51550¡88 nm). Out of the two methods tried to form bioactive
surface, EPD yields high bone adhesion when compared to the biomimetic coating.

ABSTRACT
Objectives: Endosseous dental implants are dentistry's most cutting-edge and exciting treatment choice. They're commonly
used for a number of reasons, and the majority of the approaches are evidence-based and repeatable. The aim of this analysis was to improve the surface properties of dental implant material and improve osseointegration.
Materials and Method: Two metals were tested before and after nitriding: titanium as a control group and niobium as an experimental group. they were tested by analyzing the surface roughness as in vitro study and for in vivo analysis, torque removal and histomorphometric analysis were tested.
Results: Statistical analysis conducted for the data collected from contact angle measurements, torque removal test and histomorphometric analysis by running one way ANOVA Table and multiple comparison. The lowest contact angle found in plasma nitride Niobium group, for torque removal test the highest value found in plasma nitride Niobium after 2 and 6 weeks time intervals and similar results of torque removal test obtained with histomorphometric analysis test.
Conclusion: Experimental groups significantly enhanced its surface roughness properties, torque removal test and osseointe-gration, in addition niobium metal show the excellent improvement in its properties after nitriding.

Abstract

A partial ionized plasma source of DC-glow discharge at low pressures has been
constructed, characterized, and operated as home-built plasma system. The using system
technique is a direct current discharge, formed between two metal electrodes, a flat
cathode with diameter 14.5 cm and an anode of the same shape. High voltage DC power
supply has been built for delivering 4kV maximum output to discharging electrodes. The
glow length (inter- electrodes spacing) was varied from (4-6) cm and pressure produced
from (6.5×10-2 - 1×10-1) mbar. The performance of the system via the determination of  (I-
V) and (I-P) characteristics curves was studied using N2 as discharging gas source. As a
result of ionization processes of N2 gas it is possible to estimate that the current density
values at breakdown voltage indicated the discharge is operating in the abnormal glow
region. The characteristics of glow discharge (plasma) column were observed influenced
with inter- electrode spacing and gas pressure, and the negative glow, Faraday dark and
positive column regions are recognized.

Abstract This paper reports the effect of the various
ceramic coatings viz., hydroxyapatite (HA) and partially
stabilized zirconia (PSZ) on the bond strength between the
bone and implant, and cell compatibility of screw-shaped
Ti–6Al–7Nb dental implants. Electrophoretic deposition
technique (EPD) was used to obtain a uniform coating of
one of the three types of ceramic layers (HA, PSZ and
50%HA + 50%PSZ) on the screws. Structural investiga-
tions were carried out on the prepared HA powder and the
modified surfaces of the Ti–6Al–7Nb alloy using different
techniques, namely X-ray diffraction (XRD), and Fourier
transform infrared spectroscopy (FTIR). The in vivo stud-
ies were performed by the implantation of screw-shaped
uncoated and coated implants in the tibia of white New
Zealand rabbits. To understand the bone-implant interface,
biomechanical test was carried out after 2, 6 and 18 weeks
healing periods. There was increased mechanical strength
(torque value) of bone-implant interface with time, and the
highest increment in the bond strength was recorded for
implants coated with a 50% HA and 50% PSZ. Histological
results show that the coated Ti–6Al–7Nb screws after 18
weeks of the implantation seem to be well-tolerated by the
bone since no adverse tissue reaction was evident. How-
ever, there was a faster reaction of bone towards the coated implants compared to the uncoated one. The histochemical
stain studies shows higher cellular activity and mature bone
formation on all the samples.

Abstract

Low-pressure plasma reactor which is generated for SF6, SF6/He and Ar gases discharges between two metal electrodes (planer –parallel) using dc-high voltage power supply of 2 kV has been proposed. Paschen’s curves show the breakdown voltage of gases as a function of the parameter p*d which is the product of the pressure in the chamber (P=6.5´10^-2-1.5´10^-1 mbar) and the distance between the two electrodes (d=4.6 cm). The minimum breakdown voltages were found 450 V at pressure of 1.35´10^-1mbar and 276 V at pressure of 4.3´10^-1 mbar for SF₆ and Ar, respectively. Current-voltage characteristics have been studied at different values of pressure (6.5´10^-2-1.5´10^-1 mbar) and inter- electrodes spacing (3.4, 4.2, 4.6, 5 cm). The SF₆, SF₆/He and Ar gases discharges plasmas in Si etching have been discussed.

Abstract  
The present investigation provides experimental results of corrosion performance in simulated
body fluid of Ti-20Co medical alloy coated with hydroxyapatite (HA) and Partially Stabilized
Zirconia (PSZ) composite layer by electrphoretic deposition (EPD) technique. A three mixing ratios
of HA and PSZ powders (namely 90%HA+10%PSZ, 66%HA+34%PSZ and 25%HA+75%PSZ)
were electrophoretically deposited on the surface of a Ti-20Co substrates. Post heat treatment at
800Co in inert environment was performed to improve the adhesion strength of the coated layers.
The coated samples were subjected to electrochemical study in artificial saliva (Modified Carter's
solution) and simulated blood plasma in order to determine the optimum coating conditions that can
give corrosion resistance in simulated body fluid condition. The influence of mixing ratios and
deposition thickness on the corrosion performance of the alloy are discussed in details based on the
Open Circuit Potential (OCP), corrosion potential and corrosion rate using potentiodynamic
polarization. Results showed that the coating efficiency is highly depending on parameters like
composition, coating thickness, layer porosity and adhesion to substrate. The corrosion aspects
resulting from various deposition thicknesses are discussed in details. 

BSTRACT
Background: The clinical success of implants has been achieved not only because of the mechanical strength or
excellent biocompatibility of the implant material but also because of other characteristics such as surface
properties. This study was done to investigate the optimum conditions for the electrophoresis deposition of alumina
on Ti6Al7Nb alloy.
Materials and methods: Electrophoretic Deposition technique (EPD) was used to obtain a uniform coating of Alumina
on Ti-6Al-7Nb alloy with different applied voltage and at different time. Specimens weighting and thickness
measurement of coated layer was performed for all specimens. For examination of the changes occurred on the
surface, structural analysis beside morphological investigations were carried out on the modified surfaces of the Ti-
6Al-7Nb alloy using X-ray diffraction (XRD).
Results: The result shows that the coating thickness and the weight of the coated film were increased with increasing
of the time and with increasing of the applied voltage. Ti-6Al-7Nb alloy specimens coated with alumina shows rough
surface with large number of porosity, no cracks appear on the surface of all specimens. The XRD patterns of Ti-6Al-
7Nb alloy specimen coated with alumina shows the domination of the γAL2O3 phase with presence of αAL2O3
phase. The pattern indicated that the surface of the specimen is well covered with alumina layer.
Conclusion: The electrophoretic deposition (EPD) is a good alternative coating technique for dental implant since
the thickness and surface topography of coating layer can be controlled by time, applied voltage and particles size

Abstract

This paper compares the results of the effects of a biomimetic coating and electrophoretic
deposition (EPD) of hydroxyapatite (HA) on the bond strength between the bone, implant and cell
compatibility of Ti–6Al–7Nb dental implants. In the biomimetic process, screw shaped implants
were chemically etched and NaOH activated to form hydroxycarbonated apatite after they were
soaked for six days in a solution that was five times more concentrated than regular simulated
body fluid (SBF). Electrophoretic deposition was also used to obtain a uniform coating of HA on
other batchs of screws. Elemental, structural and in vivo histological and biomechanical
investigations were carried out on the modified surfaces of the screws. The results show that there
was a faster reaction of bone towards the coated implants compared to the uncoated one. More
mature bones were observed on HA coated implants and increased mechanical strength (torque
value) of bone–implant interface. Higher torque was needed to remove elephoretically and
biomimetically HA coated screws from its bed compared to that needed for uncoated one (55,
50?16 and 37?45 N cm respectively). Biomimetic and electrophoretic coating with a bioactive HA
leads to high integration between bone and implant by increasing the bioactivity of the product
and to promoting mechanical properties of the implanted screws and enhanced osseointegration
during the healing period. Owing to the higher roughness and porosity of the EPD coated screws
(average Ra52921¡100 nm), the bone growth was much higher than that coated biomimetically
(average Ra51550¡88 nm). Out of the two methods tried to form bioactive surface, EPD yields
high bone adhesion when compared to the biomimetic coating.

ABSTRACT
Background: The clinical success of implants has been achieved not only because of the mechanical strength or
excellent biocompatibility of the implant material but also because of other characteristics such as surface
properties. This study was done to investigate the optimum conditions for the electrophoresis deposition of alumina
on Ti6Al7Nb alloy.
Materials and methods: Electrophoretic Deposition technique (EPD) was used to obtain a uniform coating of Alumina
on Ti-6Al-7Nb alloy with different applied voltage and at different time. Specimens weighting and thickness
measurement of coated layer was performed for all specimens. For examination of the changes occurred on the
surface, structural analysis beside morphological investigations were carried out on the modified surfaces of the Ti-
6Al-7Nb alloy using X-ray diffraction (XRD).
Results: The result shows that the coating thickness and the weight of the coated film were increased with increasing
of the time and with increasing of the applied voltage. Ti-6Al-7Nb alloy specimens coated with alumina shows rough
surface with large number of porosity, no cracks appear on the surface of all specimens. The XRD patterns of Ti-6Al-
7Nb alloy specimen coated with alumina shows the domination of the γAL2O3 phase with presence of αAL2O3
phase. The pattern indicated that the surface of the specimen is well covered with alumina layer.
Conclusion: The electrophoretic deposition (EPD) is a good alternative coating technique for dental implant since
the thickness and surface topography of coating layer can be controlled by time, applied voltage and particles size
distribution.

ABSTRACT
Background: Partially stabilized Zirconia(PSZ)coated implant demonstrated the distinct effects on the surface
composition of the implant, and activates on osteoblasts. Zirconia improves cell proliferation significantly during the
first days of implantation, and may improve attachment and adhesion strength of the implant. The aim of the study
was to evaluate the influence of the coated biomaterial (zirconium) on osseointegration of cpTi implant
radiographically with mechanical test.
Materials and Methods: Seventy-two commercially pure titanium implants(cpTi)were used in this study,(24)implants
were coated with PSZ by electrophoretic deposition(EPD)method,&(24) by dipping method, the rest24 implants were
used as controls, they were inserted in the tibia of (32)New Zealand white rabbits & were followed for 2,&6weeks
.Mechanical torque removal test for evaluation of osseointegration was performed,  
Results: Results revealed that bone –implant contact (BIC), increased with time &that implants coated with PSZ by
dipping method have shown higher torque mean values than those coated by EPD method.
Conclusion: Dip-coating of the cpTi implants with PSZ, can be considered as an alternative coating method and
enhance better bone implant contact than EPD.

ABSTRACT
Background: Dental implants provide a unique treatment modality for the replacement of lost dentition. Functional
surface modifications by organic material such as collagen coating seem to enhance early peri-implant bone
formation, enhancing the initial cell attachment. The aim of the study was to study the expression of osteocalcin and
growth hormone receptor as bone formation markers in collagen coated and uncoated implant in interval
periods(2,and 6 weeks).  
Materials and Methods: Commercially pure Titanium(cpTi) implants, coated with collagen protein, were placed in
the tibias of 32 New Zealand white rabbits, immunohistochemical tests for detection of expression of osteocalcin and
growth hormone receptor were performed on all the implants of both control and experimental groups for (2, and 6
weeks) healing intervals. Mechanical test (torque removal test) was performed as an indicator for the presence of
osseointegration and as a test for the mechanical property of bone-implant interface, because the torsion appears
to be primarily probing the interface mechanics.
Results: Removal torque mean values in all studied groups (uncoated and coated with collagen at two and six
healing intervals were increasing with advancing time (higher at 6 than 2 weeks periods). And coated implant
showed high value in comparison to control. Results have shown that positive reaction for OC&GHR was expressed
by osteoblast cells (OB)at implants coated with collagen ,indicating that bone formation &maturation was
accelerated by adding biological materials as a modification modality of implant surface..
Conclusion: Immunohistochemical findings revealed high positive expression range from strong to moderate of
osteocalcin and GHR in coated implant in comparison to uncoated specialy in early periods

Abstract
Titanium alloy (Ti-6Al-4V) samples were nitrided in low pressure
(1.3, 3 mbar) dc-glow discharge plasmas of nitrogen. The treating
time was 5, 10 and 15 hour and the temperatures range of the
samples during the nitriding process was close to 800oC. The
obtained microstructures of the nitride layers were studied by x-ray
diffraction and optical microscopy. The ε –Ti2N, ζ-Ti3N3-x and η-
Ti3N2-x.phases were formed and addition to the solid solution of
nitrogen in titanium, α (Ti,N). Micro hardness measurements exhibit
an increment for the Ti-alloy specimens which nitrided at 800oC for
10 and 15h.Corrosion measurements were obtained for the Ti-6Al-
4V alloy in Ringer solution after plasma nitriding. The clear
improving in the corrosion resistance was observed rather than for
untreated specimens

ABSTRACT
The colloidal non-aqueous precipitation method was used to prepare a biocompatible
magnetic ceramic–polymer composite [Hydroxyapatite/ Polyvinylachohol (HAP/PVA)]
for medical applications. The starting materials used for preparing hydroxyapatite (HAP)
were calcium nitrate and diammonium hydrogen phosphate, while the biodegradable
polyvinylachohol (PVA) and nanosized iron oxide particles (γ-Fe2O3) were used to
generate a biocompatible magnetic gel film. The results showed that the specimens of
composite containing up to 30wt% hydroxyapatite didn’t explore any of phase
separation; further the incorporated of the ferrite enhanced the affectivity and the stability
of the composite. The surface morphology and magnetic properties of the gel films were
studied and the magnetization measurements were carried out at 5-300Kº. it showed that
no remnant magnetization at 300 Kº,  but at 5 Kº hysteretic loop was observed leading to
confirm that the superparamagnetic nature of the nanosized maghemite particles didn’t
affect in presence of the polymer and its behavior considered as superparamagnetic
material.

Abstract

Three medical alloys Ti–6Al–4V, Ti–10Co and Ti–20Co were treated to form Ti nanotubes (TNTs)
by anodic oxidation process. The average diameter of TNTs for Ti–6Al–4V and Ti–10Co alloys was
35 and 100 nm respectively. Owing to the a and b phases of Ti–6Al–4V alloy, TNTs had different
morphologies. Porous and dendrite structures were formed on the surface of Ti–20Co alloy. X-ray
diffraction (XRD) patterns, optical micrograph images and scanning electron microscope images
were used to analyse the produced structures. The XRD profiles of the treated Ti–6Al–4V alloys
illustrate the amorphous, anatase and rutile structures of as anodised, annealed samples
respectively. The TNTs over bphase areas dissolved after anodic process from the surfaces of Ti–
6Al–4V and Ti–10Co alloys. Rutile phase was the dominant phase in all XRD patterns of all
annealed alloys at high temperatures. The effects of anodising process and annealing treatment
on the corrosion parameters of the used alloy surfaces inside the simulated body fluid are studied.
The annealing process enhanced the corrosion parameters for all samples due to the formation of
a thick oxide layer.

ABSTRACT
Background: Synthetic hydroxyapatite,(Ca10(PO4)6(OH2) can directly bond to bones without infection and fibrous
encapsulation, thus is regarded as bioactive and biocompatible. The aim of the study was the estimation of
microarchitecture bone parameters include bone mass (gm/cm2) cortical bone width (mm), thread width (mm),
marrow space star volume analysis (V*m) and osteoblast, osteocyte cell number.  
Materials and methods: Ninety-six (96) commercially pure titanium CpTi) used in this study, (48) implants were coated
with HA by dipping coating and (48) implants were used as control. They were inserted in (32) Newzland white rabbits
and followed for 2 & 6 weeks. Mechanical torque removal test and histomorphometric analysis of bone
microarchiteture were performed for evaluation of osseointegration.  
Results: Results revealed, Torque values were increased with advancing time for coated and uncoated groups. And
specifically dip coated implant showed high value in comparison to control. Histomorphometric analysis for bone
parameters showed highly significant difference in overall contrasted groups of implant in 2nd and 6th week interval.
Conclusion: Dip coating method is an alternative coating technique for dental implant to enhance better bone
implant contact and improve osseointegration.

ABSTRACT
 Electrochemical and structural properties of titanium implant materials with a
nanotube surface treatment and heat treatment were examined. Amorphous TiO2
nanotubes were grown homogeneously on α phase of Ti-6Al-7Nb alloy.      
    Amorphous TiO2 nanotubes were partially crystallized to rutile by heat treatment
at 8000C for 2 hrs. The corrosion potential (Ecorr) of the annealed sample had
value of -162.881mV due to the stable TiO2 crystal phase compared to the -
343.629 mV observed in the untreated sample. At 0.5 V, where a passive layer had
formed, the corrosion resistance of the annealed sample was approximately ten
times that of the untreated sample.

Abstract  
New method was used to accelerate bone osseointegration, milled and annealed fishbone was used as coating
layer on Ti-6Al-4V alloy after creating TiO2nanotube(TNTs) on it. Mechanical and thermal treatments were used
to extract natural Hydroxyapatite (HAp) from fishbone.After milling, fish bones were heated at different
temperatures. Annealed fish bones at 9000C had correspondence structure to that of standard one as X-ray
diffraction (XRD) confirmed.  After creation TNTs on screws which were made from Ti-6Al-4V alloy, EPD was
used to coat them with milled fishbone, annealed fishbone and commercial HAp. All screws were implanted
inside the tibia of white New Zealand rabbits to evaluate the biocompatibility of modified alloys and to assess
the clinical success of implants. Radiographic and histologic evaluations showed that implants with double
surface modifications illustrate new bone formation around them. These results refer to the success of all surface
modifications in this work , however the comparison between them illustrate superiority of coating by annealed
fishbone over the other coating. During implantation interval from 4 to 12 weeks, screws with double surface
modifications (creating TNTs and then coating with annealed fishbone) had highest removal torque (RTQ)
values i.e. highest osseointegration acceleration rate. After 12 weeks of implantation, torque values for screws
coated with commercial HAp are approximately equal to those values associated with screws coated with
annealed fishbone.

ABSTRACT   
Background: This study report the corrosion behavior of commercially pure titanium and Ti-6Al-4V alloy samples
without coating and with hydroxyapatite, partial stabilized zirconia and mixture of partial stabilized zirconia and
hydroxyapatite coating and comparison between them through electrochemical polarization tests in 37 0 C Hank's
solution.
Materials and methods: Electrophoretic deposition technique (EPD) was used to achieve the coating from each one
of three types of the coating materials (HAP, PSZ and mixture of 50% HAP and 50%PSZ) on Cp Ti and Ti-6Al-4V alloy
samples. The electrochemical corrosion test was performed when samples were exposed to Hank's solution prepared
in the laboratory and the polarization potential, corrosion rate and the open circuit potential of the samples were
measured.
Results: The results indicated that the corrosion rate is significantly higher for Ti-6Al-4V than for Cp Ti .The three types of
coating significantly reduced the corrosion rate for Cp Ti while did not for Ti-6Al-4V alloy .After coating the corrosion  
rate for Ti-6Al-4V remained significantly higher than the coated Cp Ti samples .The open circuit potential (OCP) for
both Cp Ti and Ti-6Al-4V samples was in the following sequence PSZ > HAP> mixture of HAP and PSZ >uncoated.
Conclusions: Cp Ti showed less corrosion rate than Ti-6Al-4V alloy with and without coating .Coating significantly
decreased the corrosion rate of Cp Ti but did not for Ti-6Al-4V alloy.

ABSTRACT
Titanium and Ti – 6Al – 7Nb alloy biomaterials have become relatively popular for
surgical implants. Plasma nitriding are commonly used for orthopaedic devices which are subjected to articulation and wear, to increase the surface hardness, and reduce the generation of wear debris. This paper aims to demonstrate the structural and elemental analysis of plasma nitrided titanium and titanium alloy. A Commercially pure titanium Cp Ti   and Ti – 6Al – 7Nb alloy were surface modified using plasma nitriding in order to study its microstructural changes. DC glow discharge plasma nitriding was performed for different period of time (namely 5, 10, 15, 20, 25 and 30 hours). The glow discharge was occurred by applying 650 V between the two parallel electrodes under 3 mbar nitrogen gas pressures. To characterize the nature of the modified layers produced and to correlate with the corrosion behavior of these medical materials, Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) was employed on the modified surfaces. The effect of sputtering process that can occur during the nitriding process on the surface roughness was studied using Atomic Force Microscopy (AFM). The results shows that as the nitriding time processed the N+ concentration increases comparing to the metal and alloy matrix elements. Also the SEM micrographs shows two effected zones of the nitriding in the modified surfaces and the thickness of each zone depend on the nitriding time. The AFM results show that the nitriding process leads to reduce the surface roughness.

Abstract: - A new biocompatible coating was developed by alternately depositing Titanium oxide(TiO2) ,with piratical size 22nm, purity 99,9 layers on CPTi  and Ti6Al4V  layers substrates using radio frequency magnetron-assisted sputter processing to improve the interface properties between the coating and the substrate .Thin film with  thicknesses(200,300 and 500nm) of polycrystalline TiO2 deposited on Ti alloys heated substrates at 100 C ̊using in argoon gas Ar with purity 99.8 under vacuum7×10-3Toor. For different power and time deposition depend on thickness of thin film. Field-emission scanning electron microscopy SEM was used to observe the surface morphologies,  microscope. microstructure captures are also taken using an optical , the Vickers Micro Hardness tests performed on each specimen and corrosion test have been carried out  to determine the optimum dose that can give good corrosion resistance in a simulated body fluid condition. The experimental results indicated that the hardness measurements exhibit an increment for the Ti-alloys specimens. Microscope ,the value of hardness decreasing for increasing thickness of thin film also there is clear improving
 in the corrosion resistance was observed rather than for untreated specially specially for 300nm thickness thin
 film.

Abstracts -Titanium and its alloys are used, because of their high mechanical properties, chemical stability, and biocompatibility. Due to its poor osteoconductive properties, coating of bioactive hydroxyapatite HAp (Ca10(PO4)6(OH)2), which has similar chemical and crystallographic structure to the main inorganic phase of human bone tissues. Reaction bonding process. Scanning Electron Microscope (SEM), Energy Dispersive X-ray Spectrometer (EDS) and X-ray Diffraction (XRD) were employed to characterize the titanium substrate and as-prepared coatings. From SEM, the interfacial bonding strength of the sintered composite coating was tested. Results show that the tripe form composite coating can be easily sintered with no cracks and decomposition at 600℃, the bonding strength to the substrate is significantly improved compared with the single HAp coating. The EDS result, A concentration weight Ca , P increasing with time of working sputtering. The results of the X-ray diffraction pattern revealed that the sputtering shows a thin layer coating contain nano size crystals. The in vitro electrochemical measurement results also indicated there is improvement in corrosion resistant of  single layer and triple layer coated compare with the uncoated as fallows, 30716, 508276 and 23176 Ω(ohm) respectively this improvement related triple layer HAp using  RF sputtering .

Abstract
The aim of this paper is to prepare a protective coating on API 5L (carbon steel) alloy which is the widely used materials in oil industry and study its effect on the corrosion behavior of the carbon steel in crude oil environment. Unsaturated polyester (UP) and clay were used to prepare composite consist of 75% of polyester and 25% of clay. The coated specimen was investigated in comparison to uncoated and 100% polyester coated specimens. X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) were employed on the coated specimens to understand the phases formed on the modified surfaces. The corrosion behavior of the modified surface in comparison with untreated one was investigated by potentiodynamic cyclic polarization in 3.5 M of NaCl and crude oil solution using Solartron made electrochemical interface SI 1287 and Electrochemical Impedance Spectroscopy (EIS) measurements at OCP condition using Solartron make 1255 HF frequency response analyzer (FRA). The results show improvement in the corrosion parameters predicted from the polarization test.

Abstract:

The present work is a part of a scientific study conducted among several Arab countries in west Asia, under an International Atomic Energy Agency (IAEA) regional technical cooperation project for Arasia region. The project aims at producing for the first time a database of particulate matter (PM) elemental concentrations in the region that will help in future air quality studies in order to identify commonalities and differences in the presence and contribution of fingerprint pollution sources among the Arasia Member States. The first regional campaign was launched simultaneously in Lebanon, Iraq, Jordan, Syria and United Arab Emirates, using a harmonized sampling and analysis protocol of PM10 and PM2.5 samples. Different samples, collected between October 2014 and February 2015, from the participating countries, were analyzed by PIXE technique and gravimetric measurements were also carried out. The first results of the study will be discussed in a regional perspective. Our study shows that concentrations of fine aerosol fractions are often exceeding the WHO standard values as well as showing some disparities in the obtained values between the different sampling sites. However, some trend similarities of variations with time could also be observed, suggesting a common influence by trans-boundary or external sources of air pollution.

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ABSTRACT
Background: In clinical trial studies, the success of dental implant depends on excellent biocompatibility, mechanical strength and characteristic of material such as surface properties of material.
The Objective of this study was to evaluate the effects of coating implants with two materials (Al2O3 &HA) .And this was   in mixture form or in two layers form. Then their effect on the bond strength at the bone/implant interface with cell compatibility was evaluated.
Materials and methods: Electrophoretic deposition technique (EPD) was used to obtain a uniform coating for each one of two types of coated layers on the screws (mixture of 50%HA and 50% Alumina and two layers). For examination of the changes occurred on the surface, structural ,elemental analysis and morphological investigations were carried out on the modified surfaces of the Ti-6Al-7Nb alloy using different techniques, namely X-ray diffraction (XRD), and Energy Dispersive X-ray Fluorescence (EDXRF). The in vivo study was done by the implantation of tapered screw–shaped uncoated and coated implants of 3mm diameter, 8 mm length (the threaded part is 5 mm and the smooth part is 3 mm) and 0.5mm pitch height.The tibia of white New Zealand rabbits were chosen as  implantation sites. The right tibia of rabbit received two screws, (one uncoated and coated) while the left tibia of a rabbit received coated screws of two layers. To understand the bone-implant interface, biomechanical test was performed after 2, 6 and 18 weeks healing periods. 15 rabbits were sacrificed for each period. A removal torque was done for ten animals in each group, whereas the other five ones were used for histological testing with optical microscope.
Results: The results indicates that there was a rapid reaction of bone towards coated Ti-6Al-7Nb alloy implants as compared with the uncoated one and more mature bone was observed after 6 weeks of implantation in screws coated with a mixture of Alumi-na and HA. The biomechanical test revealed that there was an increase in the torque mean value at bone-implant interface with time, with the highest mean values of bond strength in implants coated with a mixture of 50% HA and 50%Alumina. Also the bond strength of two layers coating was more than that of uncoated.
The results of histological examination revealed a well tissue response with the formation of a lamellate and haversian type of osteon tissue after 18 weeks.
Conclusion: this study concludes that coating by electrophoresis proved to be a valuable process to coat metallic implants with an osteoconductive material, and to form a uniform biocomposite and multiple layer coating. The biomechanical and biological properties of the bone-implant interface associated with the coated implants were improved comparing to the uncoated ones  they have better mechanical properties and excellent biocompatibility through the improved performance of bone at the site of a bone implant contact area than the uncoated implants.

ABSTRACT
Background: Prevention of surgical site infections at an early stage of implantation is an important goal for the long-term success of implants in dentistry. The aim of the study was to evaluate the mechanical properties of niobium-polyethylene glycol (Nb2O5-PEG 3500) biocomposite film formed by radio frequency (RF) magnetron plasma sputtering after immersion in antimicrobial glycol peptide (vancomycin). Materials and methods: RF magnetron technique was used to obtain a uniform and thin coating on commercially pure titanium substrates with certain sputtering parameters. Niobium oxide (Nb2O5) and niobium oxidepolyethylene glycol composite (Nb2O5PEG) coatings were characterized by X-ray diffraction (XRD) for evaluation of structure and coating thickness measurement. The femur of 10 white New Zealand rabbits was selected as implantation site, each femur received two screws, the proximal screw was coated with Nb2O5PEG composite film after immersion in the antimicrobial peptide (AMP) and the distal one was coated with Nb2O5. The mechanical assessment was performed to record new bone formation between the implant and original bone, after 2nd and 6th week healing periods. Results: Antimicrobial biocomposite coated implants showed a statistically significant increase in new bone formation in comparison to niobium oxide coated implants represented by an obvious increase in removal torque mean values at the 2nd week and 6th week after implantation. Conclusion: Coating commercially pure titanium implant with the antimicrobial biocomposite coating enhances the osseointegration at the bone-implant interface over the two periods of time.
 

Abstract:

Triple-layered RF magnetron sputtered HAp/Al2O3/TiO2 coatings synthesized onto Ti-6Al-4V alloys were stu-died to improve the surface biocompatibility and corrosion resistance features. It was seen that the HAp layers played a substantial role in the biocompatibility, while the intermediate Al2O3/TiO2 layers were used to enhance the corrosion behavior of the substrate. XRD results showed an enhanced crystallinity along with the (2 1 1) HAp phase after the simulated body fluid (SBF) immersion experiment. Local electronic and chemical bonding states of atomic phosphorus and calcium phosphate groups in the coatings, before and after immersion process, were confirmed via XPS studies. The electrochemical impedance spectroscopy (EIS) evaluated the corrosion, which indicated a reduction in capacitance values and a significant improvement of the corrosion resistance of such coatings; with improved bio-medical properties of Ti alloys.

Abstract
DC glow discharge plasma nitriding is the process of surface hardening through the spread of nitrogen atoms to the metal surface under special conditions of the plasma nitriding. Titanium and titanium alloys are the most common alloys used in medical applications. Titanium and its alloys are lightweight, corrosion resistant, and have good fatigue properties but lack wear resistance under aggressive environments. The plasma nitriding process was used for a titanium alloy (Ti–6Al–4V) rod with different parameters at a vacuum chamber of air (2 mbar), 680 volts and 30 mA. The plasma nitriding process was performed at different nitriding times (5, 10, and 15 h), and the effect of plasma nitriding was examined on the chemical compassion of Ti–6Al–4V alloy and the appearance of phases was studied by optical microscopy (OM), scanning electron microscopy and field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), Tafel potential polarization, and cyclic polarization. The results indicate that the formation of layers and phases  Ti2N and Ti2N3−x on a surface of the alloy were achieved, which would improve the surface characteristics of chemical corrosion in simulated body fluid.
 

1250 Indian Journal of Forensic Medicine & Toxicology, January-March 2020, Vol. 14, No. 1
Deposition of TaN Film on Commercial Pure Titanium
Disk by Modified Reactive Plasma Sputtering Technique
Hassan Jawad Farhan1, Raghdaa Kareem Jassim2, L.Thair3
1Assistant lecturer Department of prosthodontics. College of dentistry. University of Karbala, 2Professor. Head of Department of Prosthodontics. College of dentistry. University of Baghdad, 3Chief researcher,
Ministry of Science and Technology, Iraq
Abstract
Background: The new trend of implants is to find materials which accelerate bone formation at bone implant interface and improve Osseo integration to provide immediate or early loading after placement and eliminate waiting period which is uncomfortable and disturbs patients. Titanium as an implant material still need some improvement of surface properties physically and chemically. Tantalum which is gaining more attention as a new metallic biomaterial. Coating layer over implant is an important way for improvement of surface properties of titanium. Plasma used for surface modification, has several advantages such as changing surface topography, increasing surface roughness and in increasing the wettability of the surface.
Aim of study: To evaluate the effect of TaN coating by modified plasma sputtering technique of commercially pure titanium disk on wettability, surface roughness, surface chemical composition in comparison to noncoated surface.
Materials and method: Two groups were tested in this study which include non -coated commercial pure titanium disks and coated commercial pure titanium with TaN. Modified reactive plasma sputtering apparatus was used to coat CpTi with TaN at 4, 6 &8, h. Surface characterization by x-ray diffraction (XRD) analysis, scanning electron microscope (SEM), energy dispersive spectroscopy(EDS), contact angle measurement, were carried out for coated and uncoated disks.
Results: The result of coating specimen with TaN at times (4,6&8) h showed that 8 h coating time was the best time. And this was according to the results of X-ray diffraction analysis which show a new peak formation of Ta N coated CpTi disk which was not present in non- coated CpTi disk. The results of wettability test for CpTi disk coated with TaN disk was more than wettability of non- coated CpTi disk. Surface Roughness was more and better distributed in CpTi coated with TaN disk than non- coated one which appear clearly in electron microscope.
 

Abstract
Tribocorrosion covers the science of surface transformations resulting from the interaction of mechanical loading and chemical reactions that occur between elements of a tribosystem exposed to corrosive environments. Implant materials are subjected to relative movements, which can cause wear damage, together with corrosive attack of the body fluids. Ti–6Al–4V alloy has been widely used for this purpose due to its superior biocompatibility and excellent corrosion resistance and good mechanical properties. The purpose of this work is to evaluate the tribocorrosion of Ti–6Al–4V alloy under different load and surface conditions. The tribocorrosion tests of Ti–6Al–4V alloy were performed using pin on disc tests at phosphate buffer saline solution (PBS), under various loading (0.5–25) N and surfaces roughness (240, 320, 400, 600) μm grits. Surface morphology, chemical composition and tribocorrosion resistance studied by scanning electron microscopy (SEM), energydispersive spectroscopy (EDS) and Tafel potential polarization. The result indicate, by increasing contact load, the smoother surface (600 μm grit) give lower average tribocorrosion current density as compared with surface (320, 240, 400) μm grits suggesting that the damage is more pronounced on the smooth surface.
 

Abstract
Background: The new trend of implants is to find materials which accelerate bone formation at bone implant interface and improve Osseo integration to provide immediate or early loading after placement and eliminate waiting period which is uncomfortable and disturbs patients. Titanium as an implant material still need some improvement of surface properties physically and chemically. Tantalum which is gaining more attention as a new metallic biomaterial. Coating layer over implant is an important way for improvement of surface properties of titanium. Plasma used for surface modification, has several advantages such as changing surface topography, increasing surface roughness and in increasing the wettability of the surface.
Aim of study: To evaluate the effect of TaN coating by modified plasma sputtering technique of commercially pure titanium disk on wettability, surface roughness, surface chemical composition in comparison to noncoated surface.
Materials and methods: Two groups were tested in this study which include non -coated commercial pure titanium disks and coated commercial pure titanium with TaN. Modified reactive plasma sputtering apparatus was used to coat CpTi with TaN at 4, 6 &8, h. Surface characterization by x-ray diffraction (XRD) analysis, scanning electron microscope (SEM), energy dispersive spectroscopy(EDS), contact angle measurement, were carried out for coated and uncoated disks.
Results: The result of coating specimen with TaN at times (4,6&8) h showed that 8 h coating time was the best time. And this was according to the results of X-ray diffraction analysis which show a new peak formation of Ta N coated CpTi disk which was not present in non- coated CpTi disk. The results of wettability test for CpTi disk coated with TaN disk was more than wettability of non- coated CpTi disk. Surface Roughness was more and better distributed in CpTi coated with TaN disk than non- coated one which appear clearly in electron microscope.

Abstract. By using a low-temperature plasma glow discharge with argon gas and C2H2 as a carbon source, niobium carbide thin films were applied on a commercially pure titanium substrate. The coatings were deposited in three different deposition times: Group-1 with 2-h deposition time, group-2 with 4-h deposition time and group-3 with 6-h deposition time. The films were analysed for phase composition, microstructure, surface morphology, roughness and wettability as a function of deposition time. The X-ray diffraction (XRD) patterns suggest the formation of various phases (either orthorhombic-Nb2C or cubic-NbC). It is worth noting that deposition time affects the crystal structure of both phases, with Nb2C having a more noticeable effect due to a noticeable shift in the related XRD pattern. This might be attributable to changes in carbon content and sputtered niobium ions throughout the deposition process when the chamber gas conditions were verified to form phase pure NbC. The scanning electron microscopy images of the deposited NbC films display a microstructure that shows good regularity and homogeneity; a uniform morphology is revealed with an agglomerating characteristic of the material. Increased deposition time results in less surface roughness, according to atomic force microscope analysis. In contrast, the measurements of the water contact angle revealed only a little improvement in wettability as the deposition period increased.

Background. Material tribology has widely expanded in scope and depth and is extended from the mechanical 1eld to the biomedical 1eld. )e present study aimed to characterize the nanocoating of highly pure (99.9%) niobium (Nb), tantalum (Ta), and vanadium (V) deposited on 316L stainless steel (SS) substrates which considered the most widely used alloys in the manufacturing of SS orthodontic components. To date, the coating of SS orthodontic archwires with Nb, Ta, and V using a plasma sputtering method has never been reported. Nanodeposition was performed using a DC plasma sputtering system with three di9erent sputtering times (1, 2, and 3 hours). Results. Structural and elemental analyses were conducted on the deposited coatings using XRD, FESEM, and EDS showing a unique phase of coating metals over their substrates with obvious homogeneous even deposition. A highly signi1cant positive correlation was found between sputtering time and thickness of the achieved coatings. AFM revealed a reduction in the surface roughness of 316L SS substrates sputtered with all coating materials, signi1cantly seen in V coatings. Conclusions. Sputtering time and coating material play a signi1cant role in terms of microstructure and topography of the achieved coatings being the best in the Ta group; moreover, surface roughness was signi1cantly improved by V coatings. Likewise, it is found to be sputtering time independent for all used coatings.

Background. Nanocoating of biomedical materials may be considered the most essential developing 0eld recently, primarily directed at improving their tribological behaviors that enhance their performance and durability. In orthodontics, as in many medical 0elds, friction reduction (by nanocoatings) among di4erent orthodontic components is considered a substantial milestone in the development of biomedical technology that reduces orthodontic treatment time. )e objective of the current research was to explore the tribological behavior, namely, friction of nanocoated thin layer by tantalum (Ta), niobium (Nb), and vanadium (V) manufactured using plasma sputtering at 1, 2, and 3 hours on substrates made of 316L stainless steel (SS), which is thought to be one of the most popular alloys for stainless steel orthodontic archwires. )e friction of coated 316L SS archwires coated with Ta, Nb, and V plasma sputtering is hardly mentioned in the literature as of yet. Results. An oscillating pin-on-plate tribological test using a computerized tribometer was performed by applying a load of 1 N for 20 minutes under the dry condition at room temperature (25°C) to understand their role in the tribological behavior of the bulk material. Ta and Nb were found to reduce the friction of their SS substrate signi0cantly (45 and 55%, respectively), while V was found to deteriorate the friction of its substrate. Moreover, sputtering time had no substantial role in the friction reduction of coatings. Conclusions. Nanocoating of 316L SS bulk material by Nb and Ta with a 1-hour plasma sputtering time can enhance dramatically its tribological behavior. Higher coating hardness, smaller nanoparticle size, intermediate surface coating roughness, and lower surface binding energy of the coatings may play a vital role in friction reduction of the coated 316L SS corresponding to SS orthodontic archwires, predicting to enhance orthodontic treatment.