• د. ثائر لطيف مزعل
  • Thair Latif Alzubaydi
  • تدريسي : قسم تقنيات صناعة الاسنان
  • Teaching : Dental industry techniques
  • دكتوراه فيزياء / مواد حيوية
  • PhD. Biomaterials
  • thair@esraa.edu.iq
  • phythair2011@gmail.com
  • المقررات المكلف بها

    المقررات المكلف بها

    المقررات المكلف بها - 4
    القسم المرحلة الفصل رمز المقرر الوحدات توصيف المقرر
    قسم تقنيات صناعة الاسنان المرحلة الاولى فصل اول DMA20100 8 Dental material
    قسم تقنيات صناعة الاسنان المرحلة الثانية فصل اول 8 dental materials
    قسم تقنيات صناعة الاسنان المرحلة الثالثة سنوي 0 طرق بحث
    قسم تقنيات صناعة الاسنان المرحلة الثانية فصل ثاني 8 Dental material 2nd
    المحاضرات الالكترونية

    المحاضرات الالكترونية

    المحاضرات الالكترونية - 26
    العام المقرر القسم المرحلة المحاضرة
    2022-2023 dental materials قسم تقنيات صناعة الاسنان المرحلة الثانية : Gold alloys used for fixed restoration fabrication/14h week
    2022-2023 dental materials قسم تقنيات صناعة الاسنان المرحلة الثانية Gold alloys used for fixed restoration fabrication/13h week
    2022-2023 dental materials قسم تقنيات صناعة الاسنان المرحلة الثانية Investing and Investment /11th -12th week
    2022-2023 dental materials قسم تقنيات صناعة الاسنان المرحلة الثانية Dental Polymers/10th week
    2022-2023 dental materials قسم تقنيات صناعة الاسنان المرحلة الثانية Dental Polymers/10th week
    2022-2023 dental materials قسم تقنيات صناعة الاسنان المرحلة الثانية Synthetic Polymers-9w
    2022-2023 dental materials قسم تقنيات صناعة الاسنان المرحلة الثانية Dental Waxes /8th week
    2022-2023 dental materials قسم تقنيات صناعة الاسنان المرحلة الثانية Impression materials/7th week
    2022-2023 dental materials قسم تقنيات صناعة الاسنان المرحلة الثانية Impression materials/6th week
    2022-2023 dental materials قسم تقنيات صناعة الاسنان المرحلة الثانية Introduction to Tarnish and Corrosion-5th W
    2022-2023 dental materials قسم تقنيات صناعة الاسنان المرحلة الثانية Biological and Physical Properties/4rd week
    2022-2023 dental materials قسم تقنيات صناعة الاسنان المرحلة الثانية Materials Properties-3rd W
    2022-2023 dental materials قسم تقنيات صناعة الاسنان المرحلة الثانية Dental Materials-2nd w
    2022-2023 dental materials قسم تقنيات صناعة الاسنان المرحلة الثانية Materials Science& terms used in dental materials
    2021-2022 Dental material قسم تقنيات صناعة الاسنان المرحلة الاولى Polymers-12th w
    2021-2022 Dental material قسم تقنيات صناعة الاسنان المرحلة الاولى Polymers-11th w
    2021-2022 Dental material قسم تقنيات صناعة الاسنان المرحلة الاولى Metals and Alloys-10th w
    2021-2022 Dental material قسم تقنيات صناعة الاسنان المرحلة الاولى Metals and Alloys-9th w
    2021-2022 Dental material قسم تقنيات صناعة الاسنان المرحلة الاولى Mechanical Properties of Dental Materials-8th w
    2021-2022 Dental material قسم تقنيات صناعة الاسنان المرحلة الاولى Biological Properties of Dental Materials-7th w
    2021-2022 Dental material قسم تقنيات صناعة الاسنان المرحلة الاولى Thermal Properties of Dental Materials-6th w
    2021-2022 Dental material قسم تقنيات صناعة الاسنان المرحلة الاولى Optical properties of Dental Materials-5th w
    2021-2022 Dental material قسم تقنيات صناعة الاسنان المرحلة الاولى physical properties of dental Materials-4th w
    2021-2022 Dental material قسم تقنيات صناعة الاسنان المرحلة الاولى physical properties of dental Materials-3rd w
    2021-2022 Dental material قسم تقنيات صناعة الاسنان المرحلة الاولى Structure of Solids/2nd week
    2021-2022 Dental material قسم تقنيات صناعة الاسنان المرحلة الاولى Requirements and Evaluation of DM/1st week
    البحوث

    البحوث

    2004 Surface Engineering

    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.

    2007 Journal of Engneering and Technology

    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.

    2008 J Bagh College Dentistry

    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)
     

    2009 Surface Engineering

     

    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.

    2009 Journal of Materials Science, Materials in Medicine

    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.

    2011 J Bagh College Dentistry

    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

    2011 Surface Engineering

    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.

    2011 J Bagh College Dentistry

    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.

    2011 J Bagh College Dentistry

    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

    2012 J Bagh College Dentistry

    ABSTRACT
    Background: physicochemical and biochemical coating techniques that are investigated now a day to enhance
    bone regeneration at the interface of titanium implant materials. The combination, however, of both organic and
    inorganic constituents is expected to result into truly bone-resembling coatings and as such to a new generation of
    surface-modified titanium implants with improved functionality and biological efficacy. This research was conducted
    to study the expression of osteocalcin and growth hormone receptor as bone formation markers in coated and
    uncoated implant in interval  periods (3days,1,2and 6 weeks).,
    Materials and methods: Commercially pure titanium (CpTi) implants coated with hydroxyapatite by EPD method and
    with fibronectin protein, were placed in the tibia of (16) New Zeland 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 (3days,1,2 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 to be primarily propping the interface machanics.  
    Results: The removal torque mean values in all studied groups uncoated and coated were increasing with
    advancing time (higher at 6 than 2 weeks periods) and coated implant showed high value in comparsion to control.
    Result shows that Immunohistochemical findings revealed high positive expression range from strong to moderate for
    osteocalcin and growth hormone receptor in coated implant in comparison to uncoated. These results indicating
    that a mixing of bioactive HA ceramic and FN increased the activity of coated layer which improved the bone
    formation and maturation in bone-implant interface and enhance mechanical interlocking with bone.
    Conclusions: The present study concludes that organic and inorganic surface modification for titanium implant
    surface by HA and FN enhances bone formation and increase osseointegration.

    2014 Journal of Natural Sciences Research

    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.

    2014 J Bagh College Dentistry

    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.

    2014 Eng. & Tech. Journal

    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.

    2016 Iraqi Dent. J

    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.

    2018 International Journal of Medical Research & Health Sciences,

    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.
     

    2019 Indian Journal of Forensic Medicine & Toxicology

    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.
     

    2020 Indian Journal of Forensic Medicine & Toxicology

    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.

    2023 International Journal of Biomaterials

    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.