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Article
Effect of Hydroxyapatite Coatings on Corrosion Behavior for Biotype 316L SS Used in Orthopaedic Applications
تاثير الطلاء بمركب الاحيا- سيراميك على سلوك التاكل لسبيكة الفولاذ المستخدمة في حقل جراحة ا لعظام

Author: Abdulsalam Khashan Swadi عبد السلام خشان سوادي
Journal: Baghdad Science Journal مجلة بغداد للعلوم ISSN: 20788665 24117986 Year: 2010 Volume: 7 Issue: 3 Pages: 1237-1243
Publisher: Baghdad University جامعة بغداد

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Abstract

Electrochemical corrosion of hydroxyapatite (HAP) coated performance depends on various parameters like applied potential, time, thickness and sintering temperature. Thus, the optimum parameters required for the development of stable HAP coatings was found by using electrophoretic deposition (EPD) technique. This study discusses the results obtained from open circuit potential-time measurements (OCP-time), potentiodynamic polarisation and immersion tests for all alloy samples done under varying experimental conditions, so that the optimum coating parameters can be established. The ageing studies of the coated samples were carried out by immersing them in Ringer’s solution for a period of 30 days indicates the importance of stable HAP coatings to prevent corrosion on the substrate material, so that enhancement to the biocompatibility will be increased.

العمليات الكهروكيميائية التي تختص بدراسة مقاومة التاكل في مشبهات محاليل الجسم تعتمد على العوامل الحاكمة والمؤثرة اثناء عملية الطلاء ( الفولتية المجهزة، سمك طبقة الطلاء ودرجة حرارة التلبيد) . ان طريقة الطلاء بترسيب الدقائق المشحونة العالقة وجدت كافضل تقنية للحصول على طبقة طلاء منتظم ومستقر لمركب الهيدروكسي ابتايت (هاب) على سطح السبيكة. في هذا البحث تمت مناقشة نتائج المتغيرات التي تعتمد عليها دراسات التاكل (قياسات الدائرة المفتوحة مع الوقت، الاستقطاب الديناميكي وعمليات الغمر في مشبهات محاليل الجسم) لجميع العينات المطلية بمادة هاب وكذلك غير المطلية لاجل المقارنة بينهما. لقد اظهرت نتائج غمر النماذج المطلية لمدة 30 يوم في المحلول المحضر و من خلال دراسة صور المايكروسكوب عدم حصول تاكل لتلك العينات وهذا يفسر اهمية الطلاء بمادة هاب لكونها تمنع حصول عملية التاكل اضافة الى التوافقية البايولوجية التي تمتاز بها.


Article
Variables Affecting Developments of Hydroxyapatite Coating by Using Electrophoretic Deposition Technique
العوامل المؤثرة على تطوير اساليب الطلاء بمادة الهيدروكسي ابتايت باستخدام تقنية الطلاء بهجرة الدقائق العالقة المشحونة

Author: Abdulsalam Khashan Swadi عبدالسلام خشان سوادي
Journal: Baghdad Science Journal مجلة بغداد للعلوم ISSN: 20788665 24117986 Year: 2008 Volume: 5 Issue: 3 Pages: 423-426
Publisher: Baghdad University جامعة بغداد

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Abstract

Electrophoretic Deposition (EPD) process offers various advantages like the fabrication of the ceramic coatings and bodies with dense packing, good sinterability and homogenous microstructure. The variables namely (applied potential, deposition time and sintering temperature) affected the development of hydroxyapatite (HAP) coatings. The coating weight and thickness were found to increase with the increase in applied potential or coating time. Sintering temperature was found to affect in change phases of the metal, furthermore the firing shrinkage of the HAP coating on a constraining metal substrate leads to serve cracking. XRD Characterization indicates the formation of a contamination free phase pure, and the optical micrographs show the relatively uniform distribution of the HAP coatings. Analysis of the stiochiometric HAP before EPD process and after sintering indicates that the structural aspects do not change i.e. the EPD in ethanol does not affect the structure of HAP powder.

تتميز تقنية الطلاء بهجرة الدقائق العالقة المشحونة بفوائد متعددة خصوصا في عمليات طلاء المواد السيراميكية والسبائك المعدنية المستخدمة في الحقول البايولوجية حيث تجب السيطرة الدقيقة على عدد من المتغيرات الحاكمة (الفولتية المجهزة – وقت الترسيب- درجة حرارة التلبيد) التي لها دور مهم في الحصول على شكل وسمك منتظمين لمادة الطلاء على سطح السبيكة.لقد وجد من التجارب العملية ان زيادة وزن وسمك مادة الطلاء تتناسب مع زيادة الفولتية المجهزة ووقت الطلاء. اختيار درجة حرارة التلبيد تعتبر عاملا مهما في عملية التصاق مادة الهاب على سطح السبيكة وقوة الربط بينهما ولكن درجة التلبيد الحرارية العالية تتسبب في حصول التشققات والتكسرات لمادة الهاب على سطح السبيكة بالاضافة الى انها تسبب تغير في الاطوار الداخلية للسبيكة وتتسبب في تحلل مادة الهاب وتغير خواصها.اجريت الفحوصات الطورية لبيان نقاوة مادة الطلاء وخلوها من الاطوار الاخرى غير المرغوب بها، وقد بينت الصور المجهرية بوضوح تجانس وانتظام طبقة الطلاء، وكذلك بينت الدراسة عدم تاثر مكونات الهاب نتيجة التلبيد بدرجات الحرارة العالية قبل وبعد اجراء عملية الطلاء.


Article
Electrophoretic deposition of Hydroxyapatite on tapered Ti-6Al-7Nb dental implants: Biomechanical evaluation in rabbits

Authors: Yaarob M. Salman يعرب سلمان --- Raghdaa K. Jassim رغداء جاسم --- Thair L. Al-Zubaydi ثائر الزبيدي
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2011 Volume: 23 Issue: special issue Pages: 36-41
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Advances in implant design have often focussed on altering the micro-topography and chemistry ofthe implant surface. This study was done to evaluate the effect of Hydroxyapatite (HA) coating on the bond strengthbetween the bone and tapered screw-shaped Ti-6Al-7Nb dental implants.Materials and methods: Electrophoretic deposition technique (EPD) was used to obtain a uniform coating ofHydroxyapatite on the tapered Ti-6Al-7Nb screws. Structural investigations were carried out on the HA coatingsurface of the Ti.6Al.7Nb alloy using X-ray diffraction (XRD). The in vivo studies were performed by the implantation oftapered screw-shaped uncoated and coated implants in the tibia of white New Zealand rabbits. To understand thebone-implant interface, biomechanical test was carried out after 2, 6 and 18 weeks healing periods.Results: The XRD result shows that the ceramic layer consists of highly crystalline form of hydroxyapatite and thecrystalline HA belong to characteristic peaks of (211) at 2Į 31.7o with the hexagonal symmetry. Biomechanical resultshows that there was increased mechanical strength (torque value) of bone-implant interface with time, and thegreater increase in the torque value was noticed between 6 and 18 weeks. Also the result shows that the taperedimplant coated with HA have higher removal torque values than uncoated one in different time intervals.Conclusion: The electrophoretic deposition (EPD) is a good alternative coating technique for dental implant. HAcoated implants demonstrate high torque value and early healing than uncoated implants, which is very importantin early loading of the implant


Article
The Electrophoretic Deposition of Nano Al2O3 and AgNO3 on CpTi Dental Implant (An in vitro and in vivo study)

Authors: Rsul N. Turky رسل تركي --- Raghdaa K. Jassim رغداء جاسم
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2016 Volume: 28 Issue: 1 Pages: 41-47
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Even the wide use of dental implants, still there is a proportion of implants are failed due to infection.Much considerable attention has been paid to modify the implant surface. Coating of dental implant with abiocomposite material of suitable properties can improve osseointegration. And this is the main concern of this study.The aim of present study was to evaluate the use of a biocomposite coating of dental implant with (ceramic nanoAl2O3 and metalic AgNo3) on the bond strength at bone – implant interface and tissue reaction.Materials and methods: A total number of forty-eight screws, CpTi dental implant used in this study. Half of thesescrews were coated with a biocomposite material of nano (Al2O3and AgNo3), this was done by using electrophoreticdeposition method (EFD). In invitro part of the study, analysis of the coated surface was done using: X ray diffraction(XRD), atomic force microscope (AFM), Energy Dispersive X-ray spectroscopy (EDX), Optical microscopy andScanning electron microscope (SEM). In invivo part of study, 10 white male New Zealand rabbits were used, and ascrew type of dental implant [uncoated and coated with nano (Al2O3and AgNo3)] were implanted in each tibia ofrabbit. Then biomechanical and Histological test were performed after 2 and 4 weeks healing intervals.Results: The results of biomechanical test showed a higher torque mean values of (M+SD):(14.91N.cm+2.7)and (22.5N.cm +5.31) after 2 and 4 weeks respectively. In histological examination of coated screws at 2 weeks, there isabone trabeculae occupies a base of implant bed with osteoblast andosteocyte. At 4 weeks, there is a progress inthe healing process around dental implant, and this includes: -new bone with haversian canals, osteoblast andosteocyte.Conclusion: Biocomposite coating of dental implant with Alumina and silver nitrate can be made by electrophoreticdeposition method (EPD), and a multifunctional surface has been created


Article
Optimization of Nano Hydroxyapatite/chitosan Electrophoretic Deposition on 316L Stainless Steel Using Taguchi Design of Experiments

Authors: Mohammed Jasim Kadhim --- Nawal Ezzat Abdullatef --- Makarim Hazim Abdulkareem
Journal: AL-NAHRAIN JOURNAL FOR ENGINEERING SCIENCES مجلة النهرين للعلوم الهندسية ISSN: 25219154 / eISSN 25219162 Year: 2017 Volume: 20 Issue: 5 Pages: 1215-1227
Publisher: Al-Nahrain University جامعة النهرين

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Abstract

The aim of this work is to determine the optimum parameters for deposition of chitosan and mixture of chitosan and hydroxyapatite (HA) layers using electrophoretic deposition. The layers were on 316L stainless steel substrate. Taguchi approach was utilized to select the optimum parameters for both layers. The parameters used for deposition chitosan are voltage, time and temperature while the parameters used for HA and chitosan are voltage, time, concentration and temperature. Zeta potential tests were employed to measure the solutions stability. Coating layers were characterized for thickness, porosity and nanoroughness using optical microscopy (OM) and atomic force microscopy (AFM). The results from Taguchi design of experiments demonstrated that the best conditions for deposition of chitosan and HA layers are 50 V, 5 min, 3 g HA/L and 30C. The corresponding thickness, % porosity, nanoroughness and microroughness for optimum conditions were 22 µm, 3.53, 4.48 nm and 3.85 µm respectively.

يهدف البحث الى ايجاد الظروف المثلى لترسيب طبقة طلاء الكايتوزون والهيدروكسي ابتايت على السبيكة الاساس الفولاذ المقاوم للصدا بطريقة الترسيب الكهربائي الكاثودي . حيث تم ترسيب طبقة رقيقة من الكايتوزون فضلا عن استخدامه كمادة رابطة بين دقائق طبقات الهيدروكسيباتايت. استخدم الايثانول مع نسبة 5% ماء مقطركمحلول لعملية الترسيب مع 1% من حامض الخليك لاذابة الكايتوزون. تم استخدام برنامج تاكوجي لغرض اختيار الظروف المثلى لترسب طبقة الكايتوزن وتضمنت المتغيرات: فولتية، زمن الترسيب ، ودرجة حرارة كما استخدمت نفس المتغيرات لترسيب الهيدروكسي ابتايت مع اضافة متغير اخر وهو تركيز المسحوق. تم استخدام المجهر الضوئي (optical microscopy) ومجهرالقوى الذرية (AFM) لدراسة خصائص طبقات الطلاء من سمك ومسامية وخشونة. وقد اظهرت النتائج ان افضل الظروف لترسيب الكايتووزن هي(90 فولت، 11 دقيقة و40 مº ) وكان سمك الطبقة هو8 مايكرون واقضل الظروف للهيدروكسيابتايت هي (50 فولت ، 5 دقيقة ، 3 % هيدروكسيابتايت و30 مº) وكان سمك الطبقة هو 22 مايكرون والمسامية هي 3.53% والخشونة النانوية هي 4.48 نانومتر والخشونة المايكروية هي 3.85.


Article
Evaluation of Surface Roughness of 316L Stainless Steel Substrate on Nanohydroxyapatite by Electrophoretic Deposition
تقییم خشونة السطح للفولاذ المقاوم للصدأ المطلي بطبقة من النانوھیدروكسي اباتایت بطریقة الترسیب الكھربي

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Abstract

The present work was designed on producing nanohydroxyapatite layers using electrophoretic deposition (EPD) on 316L stainless steel substrate. The EPD coatings were prepared by the deposition of hydroxyapatite (HA)-chitosan nanocomposites on different substrate roughness (polish surface, 220 grit SiC grind, and sand blast surfaces). Depositions were performed using the suspensions of HA nano particles (3 g/L) in the mixture of alcohol and distilled water (ethanol, 5 vol. %water and containing 0.5 g/L of chitosan dissolved in 1 vol.% acetic acid. Coatings were achieved on the cathode at constant voltage, time and temperature (90 V, 5 min and 40 °C respectively); the pH value was performed and fitted at 4. After deposition, the coated samples were dried at room temperature for 24 h. The surface topography of coatings was analyzed using atomic force microscopy (AFM). SEM was used to postulate both the surface and the cross section morphology of the coatings. The adhesion bonding between the deposited coatings and substrate were measured using tape tester to evaluate the adhesion bonding between the coating and substrate. The results showed the deposited coatings on sand blasted substrate has less porosity compared with the polish surface and 220 emery paper SiC grinding substrate respectively. The coating on the sand blasted substrate showed higher nanoroughness (122 nm), better adhesion bonding (removal area 15%) and higher thickness layer (12 μm) than that of the polish substrate and 220 emery paper SiC grinding substrate.

یھدف البحث الى انتاج طبقات طلاء من النانوھیدروكسیابتایت بطریقة الترسیب الكھربي على طبقة من الفولاذ المقاوم للصدا. الطلاء تم تحضیره عن طریق ترسیب النانوھیدروكسیابتایت والنانوكایتزون على سطوح خشونة مختلفة (سطح صقیل، سطح باستخدام ورق تنعیم 220 وسطح تم تخشینھ باستخدام دقائق الرمل).لأجراء عملیة الترسیب تم استخدام عالق متكون من اذابة 3 غم/لتر من الھیدروكسیابتایت في محلول یتكون من 95 % ایثانول و 5% ماء مقطر واضیف لھا 0.5 غم/لتر من الكایتزون والذي تمت اذابة الكایتوزون في 1% من حامض الخلیك. واستخدمت قیم ثابتة للمتغیرات بعد عملیة الترسیب تم تجفیف النماذج لمدة 24 ساعة بدرجة .º (فولتیة وزمن ودرجة حرارة) وكانت المتغیرات: 90 فولت و 5 دقیقة و 40 مكما تم دراسة سطوح والمقطع العرضي لسطوح الطلاء (AFM) حرارة الغرفة تم دراسة طوبوغرافیة السطح باستخدام محھر القوة الذریة ولتقییم قوة التصاق طبقة الطلاء مع المادة الاساس تم استخدام طریقة اختبار الشریط اللاصق .(SEM) یاستخدام المجھر الالكنروني الماسح اظھرت النتائج ان السطح الذي تم تخشینھ باستخدام دقائق الرمل ابدى اعلى قیم للخشونة وأفضل قوة التصاقیھ واعلى سمك .(Tape test)للطبقة عما في السطح الصقیل والسطح الذي تم تنعیمھ باستخدام ورق التنعیم.


Article
Corrosion Performance of (Ha-Psz) Bio Ceramic Coated Ti-20Co Alloy in Simulated Physiological Media

Authors: Murtdha A. Alsaaidy --- Thair L. Alzubaydi --- Khalid R. Alrawi
Journal: Al-Nahrain Journal of Science مجلة النهرين للعلوم ISSN: (print)26635453,(online)26635461 Year: 2011 Volume: 14 Issue: 1 Pages: 84-91
Publisher: Al-Nahrain University جامعة النهرين

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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.

تم في هذا البحث دراسة نتائج فحوصات التآكل في محاليل الجسم لسبيكة Ti-2oCo ذات الاستخدام الطبي والمطلية بمادة الهيدروكسي ابتايت (HA) ومركب الزركونيا المثبتة جزيئاً (PSZ)باستخدام تقنية الترسيب بالهجرة للدقائق العالقة(EPD).حضرت ثلاثة نماذج من (Ha)و(PSZ) هي(90%HA+ 10%PSZ, 66%HA+34%PSZ ,5%HA+75%PSZ) والتي تم ترسيبها على سبيكة Ti-2oCo في محيط غاز فاصل وبدرجة 8000c لغرض الحصول على افضل التصاق بين السبيكة والمواد المرسبة.تم دراسة النماذج من خلال الاختبارات الكهروكيميائية من خلال غمرها في محلول اللعاب الصناعي وبلازما الدم والتي تم تحضيرها مختبرياً للحصول على السلوك العام للتآكل عند تعرض هذه المواد لمثل هذه الضروف.النسب المعتمدة والاسماك المهيئة للعينات المستخدمة تم قياس جهد التآكل لها ومعدل التأكل من خلال غمرها في المحلول ومن ثم قياس جهد الدائرة المفتوحة للغرض باستخدام قياس جهد الاستقطاب (OCP) اظهرت النتائج ان كفاءة معدل التآكل يعتمد على عدة عوامل منها النسب المستخدمة لمواد الطلاء وسمك الطلاء والفجوات الحاملة في طبقات الطلاء اضافة الى قوة الالتصاق على السبيكة المستخدمة. وقد تم مناقشة تأثير كل من نسب التركيب وسمك الطلاء خلال تفاصيل البحث.


Article
Evaluation of osseointegration using partially stabilized zirconia coated implants by electrophoretic deposition &dipping methods

Authors: Athraa Y.Al-Hijazi عذراء يحيى الحجازي --- Thair L.AL-Zubaydi ثائر الزبيدي --- Ban A. Al-Ghani بان الغاني
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2011 Volume: 23 Issue: special issue Pages: 42-46
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Partially stabilized Zirconia(PSZ)coated implant demonstrated the distinct effects on the surfacecomposition of the implant, and activates on osteoblasts. Zirconia improves cell proliferation significantly during thefirst days of implantation, and may improve attachment and adhesion strength of the implant. The aim of the studywas to evaluate the influence of the coated biomaterial (zirconium) on osseointegration of cpTi implantradiographically with mechanical test.Materials and Methods: Seventy-two commercially pure titanium implants(cpTi)were used in this study,(24)implantswere coated with PSZ by electrophoretic deposition(EPD)method,&(24) by dipping method, the rest24 implants wereused 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 bydipping 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 andenhance better bone implant contact than EPD.


Article
Physical and Histological Evaluation of Coated Implant with Nano ZrO2 after Creation Titania Nanotubes

Authors: Mustafa Sh. Alhilfi --- Athraa Y. Alhijazi عذراء يحيى الحجازي
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2016 Volume: 28 Issue: 4 Pages: 89-95
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: Contact between implant material and bones must be strong and fast creation, to fulfill these properties appropriate surface modifications must apply on used implants. In this contribution; double surface modifications are applied on Ti-6Al-4V alloy to accelerate osseointegration.Materials and methods: Anodic process is utilized to create titania nanotubes (TNTs) on the screws made from Ti-6Al-4V alloy. These implants were coated with nano ZrO2 particles. Second modification was annealing anodized screws at 8000C, and implanted in tibiae of nine adult New Zealand white rabbits.Results: Physical and histological consequences of two surface modifications on Ti-6Al-4V alloy screws were studied. Scanning electron microscope (SEM) images shows inhomogeneous distribution of TNTs on screws surfaces. X-ray diffraction (XRD) patterns illustrate the covering of first group samples with ZrO2 and transformation of Ti to its oxide (Rutile phase) for second group. These pattern shows that TiO2 had higher crystallinity and larger grain size than ZrO2. Atomic Force Microscopy images (AFM) shows the increasing of roughness, grain size and internal diameter of TNTs after annealing process. Coated implant with ZrO2 at 4 month duration shows threads with newly Haversian canal feature. Annealed implant at same duration shows well developed threads, base of implant illustrates bone trabeculae filled the base of implant bed with active osteoblast cells.Conclusion: Modification of implant's surface produced an improvement of osseointegration in comparison to untreated one.


Article
Assessment of Calcium Carbonate Coating on Osseointegration of Commercially Pure Titanium Implant by Torque Removal Test and Histomorphometric Analysis

Authors: Mustafa S. Mahmood --- Shatha S. Al-Ameer
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2017 Volume: 29 Issue: 1 Pages: 32-38
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: One of the most important methods to replace lost teeth is dental implants. In order to increase the strength of connection of the implant with the jaw bone to provide early loading after placement, implant is coated by different coating materials that achieved that purpose. The aim of this study was to evaluate the influence of coating CP Ti implant with calcium carbonate on the strength of bone-implant interface after two and six weeks of implantation in rabbit femur bone by torque removal test, histological and histomorphometric analysis.Materials and methods: Coating the surface of commercially pure titanium screws with extra pure synthetic calcium carbonate via electrophoretic deposition method (EPD) was done. The surface of disc samples after coating was checked by optical microscopy, X-ray diffraction examination and measurement of coating thickness. Ten male white French rabbits were prepared for implantation. Forty screws were implanted in the femur bone, two implant screws in each femur bone. The first screw is coated with calcium carbonate and compared with the second uncoated screw. Rabbits are divided into two groups according to the healing periods 2 and 6 weeks. By torque removal, the osseointegration is measured. Single screw from each group was used for histological and Histomorphometric analysis.Results: There was significant increased mean torque removal for screws coated with calcium carbonate compared with uncoated screws. Histological examination showed an increase in the growth of bone cells for coated screws, and the histomorphometric analysis showed an increase in new bone formation percent (NBFP).Conclusion: Coating the surface of the CP Ti implant with calcium carbonate via electrophoretic deposition method had great effect in increasing the osseointegration than uncoated surface.

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