Ahmed Helmy Salama, Moushira Dahaba, Amira Fares And Mohamed Sherif,

ABSTRACT
Objective: The Aim Of The Present Work Was To Study The Effect Of Anticancer Drugs On Enamel Structure, Using Scanning Electron Microscope And Digora X-ray System. Material & Methods: 30 Male Albino Rats, Aged 30 Days And Weighing 80 G Each Have Been Used In This Study, They Were Divided Into 3 Groups (10 Rats Each), Group I (control), Group II (vinblastine Group) And Group III (Taxotere Group). Vinblastine And Taxotere Were Given As A Single Intravenous Dose (4 Mg/kg) Via The Tail Vein. All Groups Were Further Subdivided Into 2 Subgroups A And B (5 Rats Each) And Were Sacrificed After 1 And 3 Weeks Respectively By Carbon Dioxide Inhalation. In Each Specific Time, The Mandible From Each Rat Was Removed And Sectioned Into Two Halves. The Incisors Cleaned Gently By Water For A Few Seconds. From Gingival Margin, Segment Of Lenght 2.8 Mm Were Measured And Dissected, Which Represent The Erupted Part Per Week. The Same Was Done For Three Weeks Groups. The Specimens Were Examined By Scanning Electron Microscope From Both Surface And Cross Section For Evaluating The Morphological Changes In The Enamel Surface And By Digora X- Ray For Evaluating The Enamel Density Of The Experimental Groups.

Results: Scanning Electron Microscope Of The Both Vinblastine And Taxotere Groups Revealed That, Variable Defective Pattrens In One-week Subgroup The Enamel Surface Showed Different Defects As Honeycomb Pattern, Variable Size Globules And Cracks. While In Three Weeks Subgroup The Enamel Surface Showed Larger Defects As Increase In The Honeycomb Pattern And More Pronounced Cracks. Statistical Analysis Results Of The Digora X Ray Measurements Revealed That, A Statistically Significant Difference Between The Control Group And The Both Vinblastine (one & Three Weeks) And Taxotere (one & Three Weeks) Subgroups. Conclusion: Both Vinblastine And Taxotere Caused Morphological Defects In The Enamel Structure. Both Drugs Caused Reduction In The Enamel Density. Vinblastine Causes Decrease In Enamel Density More Than Taxotere As Revealed By Digora X Ray System.

Mina A. Shenouda , Siza Y. Zakhari And Wafaa A. O. Segari,

ABSTRACT


Aim: The Aim Of The Current Study Was To Compare The Efficiency Of Three Single File NiTi Instruments: ProTaper F2, WaveOne Primary And One Shape In Terms Of Canal Preparation Time In Simulated Curved Canals. Methods: Sixty Endo-training Blocks (Endo Training-Bloc, Dentsply Maillefer, Ballaigues, Switzerland) With Embedded Simulated Curved Canals Were Used In This Study. The Blocks Were Divided Into Three Equal Groups According To The File Used: ProTaper F2 In Reciprocation, WaveOne Primary In Reciprocation And One Shape New Generation 25/0.06 In Continuous Rotation. The Simulated Canals Were Prepared Till Reaching The Full Working Length And Canal Preparation Time Was Calculated.

Results: One Shape Files Showed The Shortest Time For Canal Preparation (28.60 � 3.29 Seconds) Followed By WaveOne Primary (62.24 � 5.31 Seconds) And Finally ProTaper F2 Files (97.33 � 11.62 Seconds). There Was A Statistically Significant Difference Between The Three Groups (p < 0.05). Conclusion: Within The Limitations Of The Current Study, One Shape Files Used In Continuous Rotation Provided A Faster Canal Preparation In Comparison To ProTaper F2 And WaveOne Primary Files Used In Reciprocation.

Safa B. M. Alawy, Eman M. El Shourbagy And Safaa A. Ghobashy,

ABSTRACT
Aim Of The Work: The Aim Of This In Vitro Study Was To Evaluate The Effects Of Recycling And Repeated Recycling With Erbium: Yttrium Aluminum Garnet (Er:YAG) Laser On Shear Bond Strength And Surface Characteristics Of Stainless Steel Orthodontic Brackets.

Materials and Methods: Ninety Extracted Upper First Premolars And Ninety Stainless Steel Brackets Were Used For This Study. The Brackets Were Bonded To The Premolars And Were Randomly Divided Into Three Groups Of 30 Teeth/each: Group I (control), Group II (brackets Debonded And Recycled One Time Using Er:YAG Laser), And Group III (brackets Debonded And Recycled Two Times Using Er:YAG Laser). Twenty Samples From Group II And III Were Rebonded Again To The Same Re-prepared Enamel. Sixty Bonded Samples (20/each Group) Were Subjected To Shear Bond Strength Testing Using Universal Testing Machine. The Shear Bond Strength Data Were Analyzed With One-way ANOVA Test, Followed By Tukey�s Test. The Bracket/adhesive Failure Modes Were Scored As Adhesive Remnant Index. The Chi-square Test Was Used To Evaluate Statistical Differences In The Adhesive Remnant Index Scores Among Groups. Ten Debonded Brackets From Each Group Were Examined Under A Scanning Electron Microscope To Identify The Surface Characteristics Of The Brackets� Mesh.

Results: The Results Of This Study Demonstrated That The Mean Shear Bond Strength Of All Groups Were More Than That Recommended For Successful Orthodontic Bonding, There Was No Significant Difference Between Group I And Group II (P>0.05). Repeated Recycled Brackets (group III) Had Significantly Lower Shear Bond Strength (P?0.001) Than Other Groups. Scanning Electron Microscopic Analysis Showed Maximal Removal Of Adhesive From The Brackets Recycled One Time With Er:YAG Laser With Well-defined Lattice Structure, And No Damage To The Bracket Base. There Was Incomplete Removal Of The Adhesive From Repeated Recycled Brackets, Flattening And Distortion Were Observed In Two Samples. Conclusion: Er:YAG Laser Recycled Brackets Can Be Used As An Alternative To New Brackets In Case Of Bond Failure Which Might Provide Cost Reduction. However, In Case Of Second Bond Failure To The Same Bracket, It May Be Preferred To Use A New One Instead Of Reusing It For Second Time.

Karima Mansour Ali , Manal Hosny Mostafa, Olfat Shaker And Engy Ahmed,

ABSTRACT
Background: Among The Most Common Forms Of Periodontal Disease Is Chronic Periodontitis. Most Tissue Damage Found In Patients With Periodontitis Result From An Exaggerated Host Immune Response To Bacterial Challenges Which Results In The Secretion Of Proinflammatory Cytokines That Results In Destruction Of Periodontal Tissues. The Levels Of Prostaglandin E2 (PGE2) In Gingival Crevicular Fluid (GCF) Have Been Reported To Correlate Positively With Periodontal Inflammation. Nutrition Plays A Great Role In Improving The Person Quality Of Life, For Example Omega -3 PUFA Has A Well-established Anti-inflammatory Role In Periodontal Disease. Adequate Dietary Intake Of Omega-3 Polyunsaturated Fatty Acids (n-3 PUFAs) Resulted In Increases Tissue Concentration Of The Types Of Fatty Acids(e.g., Eicosapentaenoic Acid And Docosahexaenoic Acid) That Downregulate Inflammation, Omega-3(n-3)PUFA Have Multiple Actions By Which They Can Affect Cell And Tissue Behavior To Perform Their Physiological Actions. Aim Of Study: This Study Was Undertaken To Evaluate The Effects Of Omega-3 Fatty Acids Supplementation After Modified Widman Periodontal Flap Surgery On Clinical Parameters And GCF Levels Of Prostaglandin E2 (PGE2). Methods: The Present Study Had Included 40 Subjects (10 Healthy Volunteers And 30 Patients With Moderate To Advanced Chronic Periodontitis). Group I (Test Group): 15 Patients With Moderate To Advanced Chronic Periodontitis Treated With Modified Widman Flap Adjuncted With Omega 3 FA 1200 Mg Taken Orally Daily For 4 Months After MWF Surgery, Group II (Control Group): 15 Patients With Moderate To Advanced Chronic Periodontitis Treated With Modified Widman Flap Only.Evaluation Of Clinical Periodontal Parameters Were Recorded For Full Mouth And At The Most Periodontally Affected Sites (PPD ? 5mm) At Baseline And 2 And 4 Months After Periodontal Surgery.

Results: Results Of The Present Study Indicate That Daily Dietary Supplementation Of Omega 3 PUFA As An Adjunct To Surgical Periodontal Therapy Has Resulted In Improvement In Clinical Outcomes Of Pocket Depth(PD) And Clinical Attachment Level (CAL), And Significant Reduction Of GCF Markers Of Bone Resorption And Inflammation (PGE2)indicating That Omega 3 Protect Against Bone Resorption.

Yara Osman, Layla Mostafa Omara And Hassan Abd-El Ghany Osman,

ABSTRACT
Aim Of The Study: The Purpose Of This Study Was To Compare & To Assess Clinically And Radiographically, The Contact Osteogenesis Between Host Bone & Immediate Implants Placement In Narrow Anterior Region Of The Mandible Following The Use Of Manual Bone Expanders Versus Motorized Ones..

Materials and Methods: Six Patients With 12 Anterior Edentulous Areas With Narrow Ridges. Six Sites Were Subjected To Manual Bone Expanders And Six Sites Were Subjected To Motorized Bone Expanders, All Followed By Immediate Implantation. A CBCT Was Used Preoperatively, Immediate After Surgery And 6 Months Post-operatively For Dimensional And Buccolingual Expansion Analyses..

Results: During The Follow Up Period, All Patients Showed No Post-operative Complications, All The Implants Inserted Showed Successful Osseointegration With No Signs Of Failure. The CBCT Radiograph Showed Proper Contact Between The Bone And The Implant, Also Showed Increase In The Buccolingual Width For Both Groups Immediately Post-expansion And Insertion And Decrease In The Width 6 Months Post-expansion And Insertion.. Conclusion: Manual Bone Expanders Show Better Results In Expansion And Bone Density Than Motorized Bone Expanders Do..

Magda H. Mohamed, Marwa E. Sabet, Mahmoud E. Al-Homossany And Shimaa L. Mohamed,

ABSTRACT

Objectives: To Evaluate Radiographically The Effect Of The Degree Of Palatal Coverage On Marginal Bone Height Around Maxillary Hybrid -implants. Methods: Fourteen Edentulous Patients With Maxillary Conventional Denture And Mandibular Implant Retained Overdenture Were Included In This Study. Four (one Piece 3 Mm Diameter, 12 Mm Length), Implants Were Installed In Maxillary Arch Of Each Patient In Areas Of Lateral Incisors And First Premolars To Retain Maxillary Implant Overdenture Then The Upper Denture Was Modified By Reduction Of The Palatal Coverage Area For Half Of The Patients And Was Followed Radiographically For One Year.

Results: There Was Significant Difference Between The Two Groups (P ? 0.05). Conclusion: Marginal Bone Height Loss Around Implants Was Increased By Reduction Of The Palatal Coverage.

Muhammad Hamdy, Tarek I. Elfaramawi And Niveen Askar,

ABSTRACT
Objective: The Aim Of This Present Study Was To Evaluate The Relation Between Primary Implant Stability Of Delayed Implant Placement And Bone Density In Posterior Mandibular Area. Patients And Methods: 16 Implants Were Placed For 9 Patients (6 Females And 3 Males) That Had At Least A Missing One Mandibular Posterior Tooth. Bone Density Of Each Implant Site Was Measured Preoperatively Through Orthopantomograph. The Implant Osteotomy Was Done According To The Manufacture�s Instruction Under Copious Irrigation After The Replacement Of The Pilot Drill With A 2.0mm Trephine Bur To Obtain A Core Biopsy With A Fixed Starting Torque Of 15Nm2. For Each Implant Primary Implant Stability Was Measured Immediately Postoperatively By Resonance Frequency Analysis.

Results: For All The 16 Implants Sites, Bone Density Was D4. All The 16 Implants Were Stable With A Mean Primary Stability Of 69.9(+- 14.5) ISQ. Conclusion: There Is No Correlation Between Primary Implant Stability And Bone Density And Drilling Torque.

Sara G. El-Gamal, Jealan M. El-Shafei And Heba A. El-Asfouri,

ABSTRACT
Abstract: The Aim Of This Study Was To Assess The Fracture Resistance And Sealing Ability Of Endodontically Treated Teeth Obturated With Guttacore Root Canal Obturator As Compared With Thermafil Root Canal Obturator, And To Examine The Guttacore Material To Verify Its Crosslinked Structure.

Materials and Methods: Ninety Freshly Extracted Single Rooted Mandibular Premolars Were Selected For The Study. Teeth Were Divided Into The Following Groups: Group A (n=20) The Canals Were Obturated With Guttacore Endodontic Obturator And AH Plus Sealer. Group B (n=20) The Canals Are Obturated With Thermafil Endodontic Obturator And AH Plus Sealer. Group C (n=20): Root Canals Were Obturated With Conventional Gutta-percha And AH Plus Sealer Using Lateral Condensation Technique. Thirty Extra Teeth Served As Positive And Negative Control Groups. Mechanical Preparation Was Completed Using Rotary ProTaper Files Up To Size F3. Obturation Was Carried Out In Each Group According To The Manufacturer Instructions. Mechanical Testing Was Done Using A Rounded Tip Attached To Universal Testing Machine. While Linear Dye Penetration Using Silver Nitrate Dye Was Done To Assess The Apical Sealing Ability Of The Tested Materials Under A Stereomicroscope. Finally, The Guttacore Material Was Examined Under Scanning Electron Microscope And Tested For Dissolution In Solvents To Reveal Its Crosslinked Nature. Result: There Was A Non-statistically Significant Difference Between The Guttacore And Thermafil Regarding Fracture Resistance (P>0.5). However, Both Groups Showed Significantly Higher Values Than The Lateral Condensation Group. Guttacore Group Showed Statistically Significant Lower Dye Leakage Than Thermafil (P<0.5).

Conclusions: Based On Our Findings It Could Be Hypothesized That The Guttacore Material Provide Strengthening For The Root Dentin Together With Adequate Sealing Ability Properties Comparable To Lateral Condensation Technique.

Heba Ibrahim, Mohamed M. Abdel Azim And Geraldine Ahmed,

ABSTRACT
This Double Blind Randomized Clinical Trial Was Done To Assess And Compare The Efficacy Of 2% Mepivacaine Versus 4% Articaine For Inferior Alveolar Nerve Block (IANB) In Patients With Symptomatic Irreversible Pulpitis In Mandibular Molars. Subjects And Methods: 66 Participants Aged Between 18-50 Years Were Included In The Study. Only Vital Mandibular Molars With Symptomatic Irreversible Pulpitis Were Selected And Treated In One Visit. The Participants Were Randomly Assigned Into Two Equal Groups According To The Anesthetic Solution Used: Articaine Group: IANB Injection Of 3.4 Ml Articaine Hydrochloride 4% With 1:100 000 Epinephrine, Mepivacaine Group: IANB Injection Of 3.6 Ml Mepivacaine Hydrochloride 2% With 1:100000 Epinephrine. The Access Cavity Preparation And Root Canal Instrumentation Were Done 15 Minutes After IANB Injection. The Participants Ranked Their Preoperative Pain, Pain During Access Cavity Preparation And Pain During Instrumentation On Numerical Rating Scale (NRS). The Number Of Patients Who Needed Supplemental Anesthesia (intra-pulpal) Was Recorded. Obturation Was Performed Using Modified Single Cone Technique.

Results: There Was No Statistically Significant Difference Between The Two Groups In The Efficacy Of Anesthesia, Pain Intensity And Incidence At The Different Pain Categories During Access Cavity Preparation And Root Canal Instrumentation (P>0.5). There Was No Significant Statistical Difference In Supplemental Anesthesia Needed In The Two Groups (P>0.5). Conclusion: Based These Findings It Could Be Hypothesized That The Efficacy Of Anesthesia Is Similar In Both Articaine And Mepivacaine Groups In Mandibular Molars With Acute Pulpitis. Both Groups Failed To Achieve Complete Pulpal Anesthesia In Mandibular Molars With Acute Pulpitis With IANB Only And They Were Similar Regarding The Need For Supplemental Anesthesia.

Noura M. Kamal, Hend M. Salem And Heba M. Dahmoush,

ABSTRACT
Background: Salivary Gland Cancers Are A Group Of Neoplasms Having Biological, Histological And Clinical Diversity. This Diversity Represents A Challenge For Diagnosis, Classification And Management Of Salivary Gland Cancers. We Believe That The Present Study Is The First To Compare And Correlate The Immunohistochemical Expression Of EpCAM In Different Grades Of Mucoepidermoid Carcinoma (MEC) And Solid Variant Of Adenoid Cystic Carcinoma (solid AdCC) In Comparison With The Normal Salivary Glands, To Ascertain The Possible Diagnostic And Prognostic Significance As Well As, Propose EpCAM Targeted Therapy As A Possible Treatment Approach For Patients With Salivary Gland Tumors.

Materials and Methods: 60 Specimens (12 Normal Salivary Gland Tissue, 36 MEC And 12 Solid AdCC) Were Collected And EpCAM Membranous Expression Was Evaluated By Immunohistochemistry. The Total Immunoscore (TIS) Was Evaluated, Which Represented The Product Of The Proportion Score And The Intensity Score. The Term �EpCAM Overexpression� Was Given For Tissues Showing A Total Immunoscore >4.

Results: A Highly Significant Difference Was Observed Between TIS Percent Values In Control, Different Grades Of MEC And Solid AdCC (p< 0.001). High Grade MEC (HG-MEC) And Solid AdCC Were Found To Be The Highest EpCAM Expressors. Although, Lack Of EpCAM Expression Was Detected In Two Cases Of HG-MEC And One Case Of Solid AdCC. Conclusion: EpCAM Was Frequently Detected In MEC And Solid AdCC Making These Tumours Potential Targets For Anti-EpCAM Therapies. The Diffuse Membranous Expression In HG-MEC Could Be Of Diagnostic Value In Relation To The Patchy Expression Observed In Both Low Grade And Intermediate Grade MEC.

Noha S. Zein, Eman M. El-Maghraby , Dalia M. Abdel Hamid And Ahmed-Nour A. Habib,

ABSTRACT
Background: Early Childhood Caries Is Etiologically Associated With Bacterial Colonization. Streptococcus Mutans (S.mutans) Have Been Related To Dental Cariesbased On Well-defined Cariogenicity. A Body Of Evidence Suggests That Children Acquire S. Mutans Primarily From Their Mothers. It Was Also Suggested That Mode Of Child Delivery Can Lead To Differences In The Initial Foundation Of Oral Microbiota.

Purpose: To Assess The Acquisition Of S.mutans And Streptococcus Mitis (S. Mitis) In A Group Of Egyptian Infants In Relation To Mode Of Child Delivery And Maternal Salivary Bacterial Counts And Caries Index Scores. Subjects And Methods:A Total Of 50 Mothers And Their Infants Were Recruited In This Study To Assess The Acquisition Of S. Mutans And S.mitisin Relation To Mode Of Child Delivery, Maternal Salivary Bacterial Counts And DMFT Scores.

Results: Acquisition Of S. Mutans Was Significantly Higher In Cesarean-section (C- Section) Group Compared To Vaginally Delivered Group At 3 Months. S. Mitis Was Found In All Children At 3 And 6 Months Regardless The Mode Of Child Delivery. A Highly Significant Direct Correlation Between Infants� S. Mutans Counts At 3 & 6 Months And Maternal DMFT Mean Scores, As Well As Maternal S.mutans Counts Was Found. While, There Was A Highly Significant Inverse Correlation Between Infants� S. Mutans Counts At 3 & 6 Months And Maternal S. Mitis Mean Counts. Also, There Was A Highly Significant Inverse Correlation Between Infants� S. Mitis Mean Counts At 3 & 6 Months And Maternal DMFT Mean Scoresand Maternal S. Mutans Mean Counts. While, There Was A Highly Significant Direct Correlation Between Infants� S. Mitis At 3 & 6 Months And Maternal S.mitis Mean Counts.

Conclusions: C- Section Delivered Infants Had Earlier Acquisition And Higher Counts Of S. Mutans. S. Mitis Was Found In All Investigated Infants As Early As 3 Months Of Age.Early S. Mutans Acquisition In Infants Was Detected In Infants Whose Mothers Had High Maternal S. Mutans And Low S. Mitis Counts And High DMFT Scores.

Ragy Mohamed Elbadry, Sayed Hussein Saniour, Taheya Ahmed Moussa, Magdy W. Sabaa And,

ABSTRACT


Purpose: Evaluation Of The Bond Strength Of Resin Composite And Glass Ionomer Restorations To Gamma Radiated Enamel And Dentin Using A Desensitizing Agent And Different Adhesive Protocols.

Materials and Methods: Ninety Enamel And Dentin Samples (45 Each) Obtained From 15 Human Molars Were Divided Into 3 Main Groups (n=15): Control, Radiated, And Radiated/desensitized With Casein Phosphopeptide-amorphous Calcium Phosphate (CPP-ACP). The Samples Were Restored By Resin Composite (RC) Using Etch-rinse Or Self-etch Adhesives And Glass Ionomer (GI-self-adhesive) Then Sectioned To Obtain Beam-shaped Specimens. Micro-tensile Bond Strength (�-TBS) Was Measured And The Mode Of Failure Was Examined. Data Were Statistically Analyzed.

Results: Gamma Radiated Enamel/RC Showed Lower �-TBS Than The Control Group While Gamma Radiated/desensitized Enamel Restored With RC Showed The Lowest �-TBS Regardless To The Adhesives Used. Whereas, Gamma Radiated/desensitized Enamel/GI Showed The Highest Significant �-TBS Values Among The Enamel/GI Group. On The Contrary, The �-TBS Values Of Gamma Radiated Dentin/RC Using Either Adhesives Or Restored With GI Was Insignificantly Different Than Its Corresponding Control Groups. Nevertheless, Gamma Radiated/desensitized Dentin/GI Revealed The Highest �-TBS. Groups With The Low �-TBS Values Exhibited Predominantly Adhesive Or Mixed Failure Modes, While Predominance Of Cohesive And Mixed Failures Was Detected For Groups With The Higher �-TBS Values. Conclusion: Gamma Radiation Has A Detrimental Effect On The Enamel/RC Bond Strength Regardless The Adhesive Protocol Used. The CPP-ACP Has A Negative Effect On Both Enamel And Dentin Bonding To RC When Etch-rinse Or Self-etch Adhesive Protocol Were Used But Enhances That Of The Enamel/GI And Dentin/GI.

Rania Ahmed Salama,

ABSTRACT
The Current Study Was Carried Out To Experimentally Prepare An Adhesive Resin In Egypt As Well As To Evaluate Its Degree Of Conversion, Viscosity And Microtensile Bond Strength. Samples Were Divided Into Two Groups According To The Material Used: Group 1; Experimentally Prepared Adhesive, Group 2; (control); A Commercially Available Adhesive �Solobond M, Voco, Germany�. Steps Of Preparation Of The Experimentally Prepared Adhesive Resin Involved: Preparation Of The Mixture Of Monomers, Preparation Of The Photo-initiator System And Addition Of Acetone And Ethanol Solvents. Chemical Analysis Of The Experimentally Prepared Adhesive And The Commercial Adhesive (Solobond M) Was Carried Out By Means Of FTIR Spectroscopy. Evaluation Of The Experimental Adhesive Resin Was Done Regarding Its Degree Of Conversion, Viscosity And Dentin Microtensile Bond Strength. Results Revealed That The Experimentally Prepared Adhesive (group 1) Had A Statistically Significant Higher Degree Of Conversion (18.294%) Compared To The Control Adhesive (Solobond M) (13.056%). However, There Was No Statistically Significant Difference In The Mean Microtensile Bond Strength Between The Experimentally Prepared Adhesive And The Control Adhesive.

Rania Osama Abd El Halim, Souzy Farid Shinaishin And Marwa M. Abd El Hamed,

ABSTRACT
Background: Cisplatin Is Widely Used As An Effective Chemotherapeutic Agent, But It Affects Normal Tissues By Generating Reactive Oxygen Species And Free Radicals. Vitamin C Is One Of The Most Available Potent Antioxidant Agents. It Can Counteract The Damaging Effect Of Free Radicals And Harmful Oxygen-derived Species In The Tissues.

Aim: The Aim Of This Study Was To Evaluate The Apoptosis Induced By Cisplatin In Rats� Submandibular Salivary Glands And The Possible Protective Effect Of Vitamin C.

Materials and Methods: The Study Was Carried Out On 42 Male Albino Rats Weighing Between 150-200 Grams. The Rats Were Divided Into: Control Group: Rats Were Given Distilled Water Orally And Intra-peritoneal Injection Of Saline. Cisplatin Group: Rats Were Given Intra-peritoneal Injection Of Single Dose Of Cisplatin (5 Mg/kg). Vitamin C And Cisplatin Group: Rats Were Given Single Dose Of Vitamin C (100 Mg/kg) Orally And Intra-peritoneal Injection Of Cisplatin. All Groups Were Further Subdivided Into: Subgroup A: Seven Animals Were Terminated 3 Days After The Injection. Subgroup B: The Other Seven Animals Were Terminated 5 Days After The Injection. Sections Of The Processed Submandibular Salivary Glands Were Stained By Hematoxyline & Eosin And Anti-active Caspase 3 Immuno Stains To Detect The Histological Changes Induced By Cisplatin And The Possible Protective Effect Of Vitamin C.

Results: The Subgroups Received Cisplatin Revealed Degenerative Changes In The Acini And Ducts As Numerous Intracellular Vacuoles And Pyknotic Nuclei. While Those Received Vitamin C And Cisplatin Revealed More Or Less Normal Glandular Structure. Immunohistochemical Examination Revealed That The Positive Reaction To Anti-active Caspase 3 In Cisplatin Subgroups Was Significantly Higher Than The Control Subgroups Indicating Severe Apoptotic Changes While Vitamin C And Cisplatin Subgroups Revealed Significant Reduction In The Apoptotic Activity In Comparison With Cisplatin Subgroups. Conclusion: Vitamin C Had A Protective Effect Against Cytotoxic And Apoptotic Changes Induced By Cisplatin In Rat Submandibular Salivary Glands.

Ahmed Nabil Roshdy, Maged Hakim And Lamiaa Khairallah,

ABSTRACT
The Purpose Of This Is To Evaluate The Marginal Accuracy Of Press On Veneer Fabricated At Different Axial Lengths To Zirconia Core. Materials And Method: A Stainless Steel Die Resembling A Prepared Mandibular Premolar Was Machined To Allow Standardization Of The Prepared Crowns. Total Number Of Forty Ceramic Crowns Were Fabricated Using This Die. The Samples Were Then Divided Into Four Groups According To The Axial Distances From The Core To The Finish Line That Was Completed With The Veneering Material. Group 1: Zirconium Oxide Core Fabricated Till The Finish Line, Group 2: Zirconium Core 0.5 Mm Short Of The Finish Line, Group 3: Zirconium Oxide Core 1mm Short Of The Finish Line, Group 4: Zirconium Oxide Core 1.5mm Short Of The Finish Line. The Core Was Veneered And The Short Core Margins Were Completed Using Zipress Veneering Material. Then Each Group Was Thermocycled 1500 Cycles Between 5-55�C. The Marginal Accuracy Was Assessed Using Travelling Microscope.

Results: Both Group 1and 2 Showed The Statistically Significantly Highest Mean Gap Distance Values Compared To Other Two Group. There Was No Statistically Significant Difference Between 1 Mm And 1.5 Mm Groups While Both Showed The Statistically Significantly Lowest Mean Gap Distance Values. Conclusion: Despite The Advances In CAD/CAM Technique, Pressable Ceramic Using Lost Wax Technique Presented Better Marginal Adaptation Than Machined Zirconia Core Which Might Be Related To Software Limitation In Designing Restorations.

Ahmed Nabil Roshdy, Maged Hakim And Lamiaa Khairallah,

ABSTRACT
The Purpose Of This Study Is To Evaluate The Bond Strength Of Zirconia Core To Ceramic Veneer At Different Marginal Dimensions.

Materials and Methods: A Stainless Steel Die Resembling A Prepared Mandibular Premolar Was Machined To Allow Standardization Of The Prepared Crowns. Total Number Of Forty Ceramic Crowns Were Fabricated Using This Die. The Samples Were Then Divided Into Four Groups According To The Axial Distances From The Core To The Finish Line That Was Completed With The Veneering Material. Group 1: Zirconium Oxide Core Fabricated Till The Finish Line, Group 2: Zirconium Core 0.5 Mm Short Of The Finish Line, Group 3: Zirconium Oxide Core 1mm Short Of The Finish Line, Group 4: Zirconium Oxide Core 1.5mm Short Of The Finish Line. The Core Was Veneered And The Short Core Margins Were Completed Using Zipress Veneering Material. Then Each Group Was Thermocycled 1500 Cycles Between 5-55�C. The Samples Were Then Tested For Flexure Strength.

Results: There Was A Statistically Significant Decrease In Fracture Resistance After Thermocycling Within Each Of The Four Different Groups. Conclusion : The Bond Strength Of Zirconia Core And The Veneering Material Might Be Affected By The Difference In The Thermal Conductivity Between Both Materials.

Yassmin El Sayed Ahmed, Hend Abou El Nasr, Heba El Far And Mohamed Abdel Azim,

ABSTRACT
Objective: The Purpose Of This Study Was To Evaluate The Effect Of Occlusal Reduction For Mandibular Posterior Teeth On The Incidences Of Post-instrumentation And Post-obturation Pain In Patients With Symptomatic Irreversible Pulpitis And Symptomatic Apical Periodontitis. Participants And Methods: 44 Patients Were Included In The Study. All Patients Had Posterior Mandibular Teeth With Symptomatic Irreversible Pulpitis And Symptomatic Apical Periodontitis With No Evidence Of Peri-apical Radiolucencies In The Radiograph. The Patients Were Divided Randomly Into Two Equal Groups, Each Group Included 22 Participants. For The Intervention Group, All The Occlusal Contacts Of The Tooth Were Relieved From Occlusion, While For The Control Group, No Modification Was Done For The Occlusal Surface Of The Tooth. The Root Canal Treatment Was Done In Two Visits Where Root Canals Were Prepared Using Revo S Rotary NiTi Files While Obturation Was Done Using Modified Single Cone In The Second Visit. The Pain Was Assessed Preoperatively, 6, 12, 24 And 48 Hours After The Instrumentation, Then 6 And 12 Hours After The Obturation Using Modified Visual Analogue Scale (VAS). Patients Were Given A Placebo To Be Taken In Case Of Moderate Or Severe Pain And Ibuprofen 400mg Was Prescribed In Case Of Persistent Pain. Data Were Analyzed Using Chi-square And Fisher Exact Tests. Mann-Whitney U Test Was Used To Compare Between The Pain Value In The Two Groups.

Results: The Results Of The Study Showed That, There Is Significant Decrease In The Mean VAS Scores At All Follow Up Periods Compared To Pre-operative Pain Level In The Two Groups, But Postoperative Pain Intensity Was Higher With Occlusal Reduction Group Than With No Occlusal Reduction (post-instrumentation) With No Statistical Significance.

Conclusions: Within The Limitations Of This Study, We Concluded That Occlusal Reduction Isn�t An Effective Procedure To Reduce Post-operative Pain In Teeth With Symptomatic Irreversible Pulpitis And Symptomatic Apical Periodontitis. So We Still Have The Controversy Of Whether The Occlusal Reduction Decreases The Post-operative Pain Or Not, As We Still Have No Enough Evidence.

Mahmoud A. Dayekh , Moustafa Abdou Elsyad And Ahmed Khalifa Khalifa,

ABSTRACT


Aim: This Study Aimed To Examine The Retention Of Different Types Of Locator And Bar Attachments For 4-implant Supported Maxillary Over Denture.

Materials and Methods: An Acrylic Resin Model Of An Edentulous Maxilla Without Alveolar Undercuts Was Fabricated And 4 Laboratory Implants Were Inserted In The Canine And Second Premolar Areas. Mucosal Simulation Was Fabricated Over The Model. Maxillary Experimental Overdenture Were Constructed Over The Model And Connected To The Model With Either Bar Attachment (group I) Or Locator Attachment (group II). The Universal Testing Machine Was Used To Apply Vertically Oriented 4 Points Tensile Loads On A Metal Plate Attached To The Model With 4 Metal Chains Until The Attachments Separated From The Abutments. Maximum Load Needed To Dislodge The Experimental Overdenture From The Maxillary Test Model (retentive Force) Were Calculated. Initial Retentive Forces And Retentive Forces After Repeated Insertions And Removals Were Calculated

Results: Initial Retentive Forces And Retentive Forces After Repeated Insertions And Removals For Vertical Dislodging Force, Locator Transparent Recorded The Highest Retentive Forces, Followed By Locator Pink, Locator Blue And Bar Attachment Recoded The Lowest Retentive Forces.

Conclusions: Locator Transparent Recorded Significant Higher Retention Forces Compared To Other Types Of Locators And Bar Attachment. The Lowest Retention Was Recorded With Locator Blue And Bar Attachment.

Dina Gameel Anis, MahaEshakAmer And Mohamed Salah Abd Elmotamed,

ABSTRACT

Objectives: The Purpose Of The Study Was To Assess The Relation Between Clinical And Magnetic Resonance Imaging Findings In Temporomandibular Joint Disorders.

Materials and Methods: MRI Scanning And Clinical Examination Were Performed To Twenty Patients Of Both Sexes And Varying Ages, Complaining Of TMJ Disorders. The Disc Position, Disc Morphology, Condylar Osseous Changes, Retrodiscal Tissue Status And Joint Effusion Were Assessed. The Correlation Between The Clinical And MRI Findings Was Statistically Analyzed.

Results: Pain In The Temporomandibular Region Was The Most Common Clinical Presentation, It Accounts For 67.5% Of Cases. Significant Correlation Was Found Between Pain And Disk Morphology, Condylar Osseous Changes, Retrodiscal Tissue Status (p=0.001, 0.019, 0.003 Respectively)and With Disc Displacement. Statistically Significant Relationship Was Also Found Between Disk Position, Eminence Changes And TMJ Sounds (P=0.025, 0.004 Respectively), As Well As Between Disk Position And Maximum Mouth Opening (MMO)( P=0.018). There Was A Direct Correlation Between Retrodiscal Tissue Status And Mandibular Deviation (p=0.021). Conclusion: Clinical Evaluation Of The TMJ Can Be Nonspecific Due To Overlap Of Symptoms Between Internal Derangement And Myofacial Pain Dysfunction. MRI Should Be Part Of The Standard Evaluation When An Internal Structural Joint Abnormality Is Suspected .Disc Displacement As Observed With MRI Correlated Well With Clinical Signs And Symptoms.

Abdullah Salem Ibrahim, Maged Negm And Alaa El-Baz,

ABSTRACT
Seventy Six Human Single Canaled Teeth Were Decapitated, Instrumented Using K3 Ni-Ti Rotary System, And Then Divided Into 4 Main Groups Of 19 Teeth Each, According To The Type Of Irrigation Protocol Used; Group I, 1:1 Mixture Of 5.25% NaOCl + 18% Etidronic Acid (HEBP). Group II, 1:1 Mixture Of 5.25% NaOCl + 18% Etidronic Acid (HEBP), Followed By 17% EDTA As A Final Rinse. Group III, 17% EDTA. Group IV, 5.25% NaOCl (control Group). The Quantity Of Irrigation Was 5 Ml For 2 Minutes. Then, A Final Rinse Of 5 Ml For 2 Minutes Of Distilled Water. Sixteen Roots Of Each Group Were Subdivided Into 2 Subgroups (each Of 8 Roots), According To The Type Of Sealer Used: A Single Gutta-percha Cone Size 40 Taper 0.06 With AH Plus Root Canal Sealer. A Single Activ GP Cone Size 40 Taper 0.06 With Activ GP Root Canal Sealer. The Obturated Roots Were Horizontally Divided Into Three Equal Sections. The Middle Third Specimens Were Subject To Push-out Test By Means Of An Instron Testing Machine. Then, The Specimens Were Examined Under Digital Microscope To Determine The Type Of Bond Failure. The Remaining Three Roots Of Each Group Were Longitudinally Split Into 2 Equal Halves. The Walls Of Their Middle Thirds Were Examined For The Presence Of Debris And Smear Layer Under Environmental Scanning Electron Microscope (ESEM). The ESEM Showed Superior Results Of EDTA And NaOCl/HEBP/EDTA Groups Respectively In Smear Layer Removal Over NaOCl/HEBP And NaOCl Groups. It Was Found That EDTA Group Recorded The Highest Mean Value Of Push-out Test With AH Plus Sealer, While NaOCl/HEBP/EDTA Group Recorded The Highest Mean Value Of Push-out Test With Activ GP Obturation System.

Mahmoud Mohammed Abd El Gawad, Ibrahim Hasan El Kalla And Hanaa Mahmoud Shalan,

ABSTRACT

Objectives: The Aim Of This Study Was: 1-To Evaluate Adaptation And Interfacial Micromorphology Of Composite Restorations In Conservative Cavities. 2-To Evaluate Microleakage Of Composite Bonded With Different Adhesives.

Materials & Methods: Conservative Cavities (4�1.5�2mm) Were Prepared In The Occlusal Surfaces Of Ninety Sound Extracted Permanent Molars. Then, The Teeth Were Randomly Divided Into Three Equal Groups, Thirty Molars For Each Group (N=30) According To The Type Of Adhesive. Group 1: Ambar Bond, Group 2: Excite Bond And Group 3: Prompt L-pop. Then All Cavities Were Restored With Composite Resin (Filtek Z250). After That, Fifteen Teeth From Each Group Were Sectioned Buccolingually Into Two Halves To Evaluate Composite Adaptation Under Stereomicroscope (60X) For Both Halves At All Cavity Walls. Selected Specimens Were Examined Under Scanning Electron Microscope (750X) To Detect Interfacial Micromorphology. The Other Fifteen Teeth Were Thermocycled For 1,000 Cycles In Separate Distilled Water Baths Of 5�C And 55�C Then The Teeth Were Immersed In 1% Methylene Blue Dye Solution For 24 Hours At Room Temperature. The Teeth Were Sectioned Buccolingually To Evaluate Microleakage Under Stereomicroscope.

Results: All Specimens Had Voids Ranging From (0.1-1.7mm). Ambar Bond Showed The Greatest Number Of Samples That Had Voids (60%) Followed By Prompt L-pop (40%) And Excite Bond (33.3%). Microleakage Scores Were Highest With Prompt L-pop Followed By Ambar And Excite Bond. Resin Tag Lengths Were Longer With Excite And Ambar Bond As Compared To Prompt L-pop Bond. Conclusion: Restoration Of Conservative Cavities Without Voids Is Difficult To Achieve. Etch And Rinse System Is Still Considered A Gold Standard Adhesive.

Hanan M. Abdelaziz, Dina Elkassas And Heba Salah El-dein Hamza,

ABSTRACT
This Research Was Designed To Evaluate The Remineralizing Potential Of Fluoride In Comparison To Three Different Calcium Phosphate Based Remineralizing Agents Using Surface Microhardnesss Test.

Materials & Methods: A Total Of 50 Sound Human Mandibular Molars Were Used In This Study. Artificial Enamel Carious Lesions Were Induced And The Enamel Specimens Were Divided Randomly Into Five Groups, According To The Remineralizing Agent Used; Group A1: Molars Stored In Artificial Saliva, Group A2: Fluoride Varnish Was Used, Group A3: CPP-ACP Varnish, Group A4: F-TCP Varnish And Finally Group A5: Novamin Paste Was Applied. Specimens Were Then Subjected To A PH Cycling Protocol For Eight Consecutive Days. The Surface Micro Hardness (SMH) Was Assessed Using Vickers Microhardness Tester, Prior To Demineralization Of The Specimens As A Baseline (SMH/Baseline), Following Demineralization (SMH/Demineralization) And Finally, After The Remineralization Regimens & PH Cycling (SMH/Remineralization), Then Mean Surface Microhardness Recovery Percentage Was Calculated (SMHR %).

Results: Showed That The Highest SMHR% Was Found In Novamin (58.29 � 8.14) Followed By TCP (50.56 � 6.37), CPP-ACP (46.40 � 13.93) And Fluoride (34.94 � 9.35). While The Lowest SMHR% Was Found In Saliva Group (14.26 � 5.77). Conclusion: Crystalline Calcium Phosphate Based Delivery Vehicles Showed Higher Remineralizing Efficacy Compared To The Amorphous Calcium Phosphate Based And Fluoride Based Agents. Novamin Remineralizing System Confers The Highest Remineralization Tendency With The Highest Potential.

Raghda Esam El-Malt; Fatma Abdou El-Sayed And Hoda Abdel-Aziz,

ABSTRACT
Aim Of This Study: To Assess The Pubertal Growth Spurt In A Group Of Al-Giza School Male Adolescents, Using The Developmental Stages Of The Middle Phalanx Of The Middle Finger (MP3), And To Evaluate The Skeletal Maturity Age Differences Between Al-Giza Male Adolescents And Other Populations.

Materials & Methods: A Sample Of 1500 Male Students For Al-Giza Was Included In This Study With Age Range From 11 To 16 Years Was Collected. A Radiograph For The Middle Phalanx Of The Middle Finger By Digital Dental Radiograph For The Assessment Of MP3 Maturation Stages Was Taken For Each Subject.

Results: The MP3-G Stage (signifying The Peak Of Pubertal Growth Spurt) Was Found With High Prevalence In Subjects Aged >13-14 Years With Mean Of Age 13.36y. Conclusion: 1. The Mean Skeletal Maturity Age (MP3-G Stage) That Represents The Peak Of Height Velocity (PHV) In Egyptian Adolescent Males Of Al-Giza Was Found To Be 13.36 Y � 1.07 Years. 2. The Newly Digital Radiography Of The MP3 Region Is Definitely An Available, Simple Technique Of High Clarity, Low Radiation.

Karim Fouda, Hamdy Abouelfotouh And Ahmed Fahmi,

ABSTRACT
This Study Was Conducted To Evaluate The Difference Between Conventional Acrylic And Soft Lined Implant Partial Overdenture In Mandibular Kennedy Class I. The Aim Of This Work Was To Evaluate The Effect Of Using Soft Liner On Denture Base In Lower Kennedy Class I Partially Edentulous Patients Restored With Implant Supported Partial Overdenture Fourteen Partially Edentulus Patients Were Selected Patients And Divided Into Two Equal Groups. For Both The First And Second Groups: Endosseous Implant Was Placed In The Edentulous Region And Loading Was Done After Three To Four Month. In The First Group Conventional Acrylic Was Used While In The Second Group The Overdenture Was Lined With Soft Liner.For Each Patient, Radiographic Evaluation Has Been Done Immediately After Denture Insertion And After 6 And 9 Month From Prosthesis Construction. The Results In This Study Showed That There Was Statistically Significant Difference Between Both Groups In Radiographic Evaluation Regarding Bone Height But Not Bone Density.

Manar Elzanaty, Mona Shoieb, Noha A. Ghallab And Hani Essam El Nahass,

ABSTRACT
Background: Amnion Chorion Membrane Has Been Suggested In The Treatment Of Gingival Recession, Yet The Evidence Is Inconclusive. The Aim Of This Study Was To Clinically Evaluate Coronally Advanced Flap Plus Subepithelial Connective Tissue Graft Compared To Coronally Advanced Flap Plus Amnion Chorion Allograft Membrane In Management Of Patients With Miller Class I Or II Gingival Recession At 6 Month Postoperative. Methods: The Study Included Twenty Patients With 36 Teeth (6 Males And 14 Females, Aged 20 To 54 Years) Who Were Randomly Assigned To Either Group.At Baseline Clinical Parameters Were Recorded Including; Recession Depth, Recession Width, Width Of Keratinized Gingiva, Tissue Biotype, Plaque Index, Gingival Index, Probing Pocket Depth And Clinical Attachment Loss. A Coronally Advanced Flap Using The Trapezoidal Flap Technique Was Performed With The Placement Of Either The Subepithelial Connective Tissue Graft Or The Amnion Chorion Membrane.

Results: The Present Investigation Showed A Total Percentage Of Root Coverage 87.9% And 80.83% For The Subepithlial Connective Tissue Graft Group And The Amnion Chorion Allograft Group At 6 Months Respectively. The Percentage Of Complete Root Coverage Was 50% For Both Groups. Conclusion: Amnion Chorion Allograft Might Be A Suitable Alternative To Connective Tissue Graft In Procedures To Cover Denuded Root Surfaces And Can Reduce Recession Depth.

Hassan A.H. AboulAzm, Mai Mahmoud Yousry And Amir Hafez,

ABSTRACT
This Study Was Conducted To Evaluate The Effect Of Pre- And Post-bleaching On The Color Change Of Resin Infiltrated Enamel Versus Sound Enamel. M&M: A Total Of 30 Bovine Specimens Were Used, On Each; 3 Windows Were Created; Window A �sound Control�, Window B �demineralized� And Window C �demineralized And Resin Infiltrated�, A Spectrophotometer Was Used To Assess Baseline Color In Each Window Then Bleaching Was Performed For All 3 Windows And Resin Infiltration Was Done For Window B Then Final Color Was Re-assessed.

Results: No Clinical Significant Difference Was Found In Color Change (?E) Of Pre- And Post-bleached Resin Infiltrated Specimens Compared To Sound Bleached. Conclusion: Pre-bleaching And Post-bleaching Resin Infiltrated Enamel Lesions Showed A Clinically Similar Color Change To Sound Bleached Enamel.

Basel Ismaeel Alhabash And Omaima El-Mahallawi,

ABSTRACT


Introduction: In Flared Canals The Misfit Of Ready-made Glass Fiber Post At Coronal Part Leads To Increased Cement Thickness At This Area With More Liability To Voids Incorporation And De-bonding Risk. Different Methods Have Been Proposed To Solve This Problem, But Still There Is No Definite Data About The Effect Of Each Technique On Mechanical Properties Of Remaining Tooth Structure.

Materials and Methods: A Total Number (n=32) Of Freshly Extracted Central Incisor With Nearly Same Length And Diameter Were Collected And Divided To Four Groups As The Follow: Group1 (control)(n=8) Remain Sound Without Any Preparation Or Endodontic Treatment, Group2,3 And 4 Received Endodontic Treatment And Intra-radicular Flared Preparation With Same Criteria And Restored As The Follow: Group2 (n=8) Restored With Radix Fiber Post, Group3 (n=8) Restored With Relined Radix Fiber Post, Group4 (n=8) Restored With EverStick Fiber Post. Coronal Portion For All Groups Were Then Restored With Nano-hybrid Composite And All Samples Were Then Individually Mounted On Epoxy Resin Blocks And Where Loaded At 135? Of The Long Axis Using A Computer Controlled Testing Machine With A Load Cell Of 5 KN. The Specimens Were Statically Loaded Until Fracture At A Crosshead Speed Of 1 Mm/min With The Steel Rod. Kruskal-Wallis Test Was Used To Study The Different Between Tested Groups. The Significance Level Was Set At P < 0.05.

Results: Intact Teeth (control Group) Showed The Highest Mean Fracture Resistance Value (462.89 � 104.51 N). The Relined Radix Fiber Post Group Showed (392.03 � 105.34 N), Radix Fiber Post Group Showed (303.15 � 95.39 N) And The EverStick Post Showed (369.77 � 107.4 N).The Difference Between The Control And Both Relined Radix And EverStick Post Groups Were Statistically Insignificant (P > 0.05). However, The Differences Between The Radix Post Groups With All Remaining Groups Were Statistically Significant (P < 0.05). Conclusion: 1. Relining Ready-made Glass Fiber Post Or Using Individually Formable Glass Fiber Post In Maxillary Teeth With Flared Canals Increase Their Fracture Resistance. 2. Increased Resin Cement Film Thickness Adversely Affects Fracture Resistance Of Teeth With Flared Canals. 3. The Fracture Value For All Tested Groups Was Higher Than Normal Masticatory Forces In Anterior Region.

Dina Ezz El Din Mohamed , Mohamed Fouad Haridy And Mohsen Hussein Abi Alhasan,

ABSTRACT


Aim: This Study To Assess The Bonding Efficiency Of Resin Composite Using Self Etch Adhesive To Dental Hard Tissues After Remineralization With Conventional Bioactive Glass.

Materials & Methods: Conventional Bioactive Glass Particles Were Prepared. A Total Number Of 25 Extracted Caries-free Human Permanent Molars Used. 5 Specimens As A Positive Control (sound Dentin), The Remaining 20 Specimens Demineralized. The Demineralized Dentin Divided Into: 5 Specimens Negative Control (demineralized Dentin) And The Remaining 15 Specimens Divided Into 3 Groups (5 Each) According To The Period Of Application Of Conventional Bioactive Glass Particles Either One Day, One Week And One Month. After De- And Remineralization Phases, Self-etch Adhesive System Single Bond Universal Adhesive (3M ESPE, St Paul, MN, USA) Was Used According To Manufacturer�s Instructions Before Resin Composite Packing. Three Micro-tubes Were Mounted On The Uncured Adhesive To Restrict The Bonding Area. The Adhesive Coat Was Then Light Cured For 10 Seconds Using A LED Light-curing Unit (Elipar S10, 3M ESPE, St Paul, MN, USA). After Curing Of The Adhesive, The Resin Composite Was Packed In The Micro-cylinders Using Endodontic Plugger. The Packed Resin Composite Light-cured For 40 Seconds Using The Same LED Light Curing Unit. The Specimens Were Stored In Distilled Water For 24 Hours Prior To Micro Shear Bond Strength (�-SBS) Testing. �-SBS Testing Was Done Using A Universal Testing Machine (Lloyd Instruments Ltd., Fareham UK).

Results: The Sound Dentin Showed The Highest �-Shear Bond Strength (MPa) Values (23.7 � 1.54) Followed By The Remineralized Dentin (16.43 � 3.49) With The Lowest �-Shear Bond Strength (MPa) Values For The Demineralized Dentin (11.63 � 1.08). Statistical Significant Differences Existed Among The Three Tested Groups (p?0.001). Conclusion: The Conventional Bioactive Glasses Is A Very Proficient Remineralizing Agent For The Demineralized Dentin. Consequently, The Microshear Bond Strength To Dentin Was Improved After Remineralization. Moreover, Application Time Of The Remineralizing Agent Has A Profound Effect On Its Reminalization Competence.

Abdu-eddaiem J. Qidarah, Mohamed A. Tawfik, Wael M. Said And Wael M. Safwat,

ABSTRACT
Objective: The Purpose Of This Study Is To Investigate The Efficiency Of The Radiological Evaluate Of The Cone Beam Computer Tomography (CBCT) In The Diagnosis And Treatment Planning Of Odontogenic Tumors. Patients And Methods: The Study Sample Included 20 Patients (11 Male, And 9 Female), With Total 20 Odontogenic Tumors (8 Cases Of Amelobastoma, 5 OKC, 4 Odontoma, 2 Myxoma And One Case Of Cementoblastoma), The Patients Age Ranged From 10 To 70 Years, With Mean Age 30 Years. That Underwent To The Clinical, Radiographic Examination (computed Tomography (CT) And Cone Beam Computer Tomography (CBCT)) And Histopathological Examination.

Results: For Anterior-posterior Liner Measurement Of OT There Were No Significant Differences (p>0.05) Between CT, CBCT And The Intraoperative Finding. Also There Were No Significant Differences (p>0.05) Between CT, CBCT And The Intraoperative Finding For Height And Width Liner Measurement Of OT. While, Presence And Absence Of Cortical Expansion And Perforation Of OT In CT, CBCT Images And The Intraoperative Finding Was Showed There Were No Significant Differences Between CT And CBCT. Also, For The Presence Of Nerve Involvement And Displacement By OT In CT, CBCT Images And The Intraoperative Finding There Was No Statistically Significant Difference Between Two Groups. For The Presence Of Teeth Involvement (root Resorption) By OT In CT, CBCT Images And The Intraoperative Finding There Was No Statistically Significant Difference Between CT, CBCT And The Intraoperative Finding. Finally, The Maxillary Sinus Involvement By OT In CT CBCT Images And The Intraoperative Finding, There Was No Statistically Significant Difference Between CT, CBCT And The Intraoperative Finding.

Conclusions: The CBCT It Has Higher Ability To Provide Valuable Diagnostic Information Compared To Conventional Radiography Even With Its Higher Cost, Which Makes CBCT First Diagnostic Tool For Detection And Localization Of Odontogenic Tumors, And Assessment Of Odontogenic Tumors Severity, And Surgical Treatment Planning For The Odontogenic Tumors.

Maii I. M. Khalil, Cherif A. Mohsen And Shams W. A. Ali,

ABSTRACT
Statement Of Problem: Color Stability Is An Important Factor To Ensure The Long-term Clinical Success Of Ceramic Restorations. The Aim Of This Study Was To Evaluate The Effect Of Repeated Firing Cycles On Color Stability Of Three Shades Of Zirconia Ceramic System. Materials& Methods: Seventy-five Ceramic Discs Were Fabricated. Discs Were Divided Into Three Main Groups According To Their Shades. Group(1) Shade A1, Group(2) Shade A3 & Group(3) Shade A4(n=25). Then Each Group Was Subdivided Into Five Subgroups According To The Number Of Firing Cycles Done (n=15) : SG(I)No Firing Cycles (control), SG(II) 3 Firing Cycles, SG(III) 5 Firing Cycles, SG(IV) 7 Firing Cycles And SG(V) 9 Firing Cycles. Color Readings Were Obtained With A Spectrophotometer Before And After Firings And L*, A*, And B* Coordinates And Total Color Variation (?E) Were Statistically Analyzed Using IBM SPSS Software.

Results: Results Revealed That For The 3 Shades (A1, A3 &A4), Color Change (DE) Had A Statistically Significant Difference Among The Four Different Firing Cycles (3, 5, 7 And 9) As Its P=0.01.Also, The Change In Color Parameters DL, Da And Db, Among The Four Different Firing Cycles Were A Statistically Significant With P=0.01. Conclusion: The L*a*b* Values Of The Ceramic Systems Were Affected By The Number Of Firings (3, 5, 7, Or 9 Firings) And Veneering Porcelain Shade (A1, A3 Or A4). L* Value Of All Specimens (at Different Shades) Was Increased Which Means That Specimens Become Lighter After Increasing The Number Of Firings. While, A* And B* Values Were Variables. The Mean Color Differences (?E) Caused By Repeated Firings Were Sometimes Below The Perceivable Level (?E<3) And Others Above This Level (?E>3) And Represent Visually Detectable Color Differences With The Change In Ceramic Shades And Firing Cycles. Clinical Recommendations: Zirconia Ceramic Restorations Should Not Be Exposed To Repeated Number Of Firings To Not Produce Detectable Color Changes.

Emad Mohamed T. Agamy, Iman A. Elasfahani And Haytham M. AbdelAal,

ABSTRACT
Objective: The Aim Of This Study Was To Evaluate The Distribution Of Stresses In Single Implant Supported Mandibular Over Denture, By Three-dimensional Finite Element Analysis (3D FEA).

Materials and Methods: A 3D Finite Element Model Of Mandibular Overdentures Was Established, Using Single Implant With Ball And Socket Attachment. The Implant Was Inserted At The Position Of Central Incisor Area. Two Types Of Loads Were Applied To The Model: Total Of 150 N Vertical And 45 Degree Oblique Loads On The Right First Premolar, Second Premolar And First Molar. The Distribution Around Peri-implant Bone, Implant, Mucosa And Overdentures Were Recorded.

Results: The Maximum Recorded Stresses Under Vertical Loading Were 25 Mpa While Under Oblique Loading Were 36.5 Mpa. No Failure Occurred In Any Part Of The Model. All Maximum Stresses Were Less Than The Yield Strength And Within The Biological Range. Conclusion And Clinical Significance: Single-implant-retained Mandibular Overdentures Do Not Show Damaging Stress Concentration Neither In The Bone Around The Implant, Different Supporting Structures Nor The Prosthesis. In This Regard It May Be Considered A Cost Effective Treatment Option For Edentulous Patients.

Aimen Al-Gobrani, Fatma A. Abdel-Sayed, Hoda M. Abdel-Aziz And Manal Y. Fouda,

ABSTRACT
Aim Of Study: The Aim Of This Study Was To Determine The Prevalence Of Malocclusion And Orthodontic Treatment Needs Among Egyptian School Children In Matrouh Governorate In The Arab Republic Of Egypt.

Materials and Methods: Asample Of 500 Children (8-12 Years Of Age ) Were Randomly Selected From Matrouh Governorate Primary Schools. Clinical Examination Were Performed At The School Clinic.The Need For Orthodontic Treatment Was Evaluated According To Index Of Orthodontic Treatment Need (IOTN). Result: Showed That Matrouh Governorate, Accepted Occlusion Represented 13.8% Of The Total Sample Malocclusion Represented 86.2% Of The Total Sample, Were 64.0% Showed Angle Class I, 14.6% Showed Angle Class II, 6.4% Showed Angle Class III, While 1.2% Showed Angle Class IV. There Were Tendency Toward Decrease In Percent Of Accepted Occlusion And Increase In Angle Class II And III Compared To Previous Egyptian Studies There Were No Sex Differences Within All Of The Occlusal Categories Dental Health Component (DHC) Of The Index Of Orthodontic Treatment Need Showed That 15.8% Of The Total Sample Were In Great Need Of Treatment, 20.6% Showed Moderate Need, While 63.6% Showed No Or Little Need For Treatment. Aesthetic Component (AC) Of The Index Of Orthodontic Treatment Need Showed That 7.4% Of The Total Sample Were In Great Need Of Treatment, 37.6% Showed Moderate Need, While 55% Showed No Or Little Need For Treatment.

Conclusions: The Percent Of Children With Great Treatment Need Regarding DHC Were (20.6%) Lower Than In Cairo (23.5%), While Regarding AC Were (7.4%) Higher Than In Mansura (4.4%). There Were No Sex Difference Within DHC And AC Components, There Were No Correlation Between Either Of DHC Or AC Components And Mixed.

Abdallah I. Al-Saadeh, Faten H.K. Eid, Fatma A. Abdel-Sayed And Hala Munir,

ABSTRACT
This Project Was Aimed To Determine The Prevalence Of Malocclusion Among School Children In Giza Governorate.

Materials and Methods: This Study Was Carried Out In Giza Governorate Where A List Of The Primary Schools And The Number Of Primary School Children Were Obtained From The Database Of The Ministry Of Education. Giza Governorate Was Divided Into Ten Regions According To Geographical Location, Two Schools Were Chosen Randomly From Each Region Using SAS Computer Software Thus, 20 Schools Were Included In This Study And A Total Number Of 1900 Schoolchildren Were Included In This Survey.

Results: Distribution Of Angle Classification: This Study Showed That 392 Children (20.6%) Had Accepted Occlusion While, 1029 Children Had Angle Class I Malocclusion Representing (54.2%) Of The Study Sample, 300 Children Had Angle Class II Malocclusion Representing (15.8%) Of The Study Sample While 163 Children Had Class III Malocclusion Representing (8.6%) Of The Study Sample And 16 Children Had Class IV Representing (0.8%) Of The Study Sample. Overjet: The Most Frequent Category Was Normal Overjet (>0�3.5mm) Which Was Found To Be (60.5%). Anterior Open Bite (<0 Mm) Was Found In (6.9%) Of The Total Sample. Conclusion: Compared To Previous Egyptian Studies, There Was A Tendency Toward Decrease In The Prevalence Of Accepted Occlusion While, There Was An Increase In Angle Class II And III Malocclusions.

Mona E, Mohamed. Z And Rasha N.S.,

ABSTRACT

Objectives: The Purpose Of This Study Was To Evaluate The Retention Of Two Non Metallic Machine Milled Crown Materials Using Two Different Adhesive Protocols. Methods: Twenty Intact Human Molars Were Used; Teeth Were Divided Into Two Main Groups According To The Crown Material Used, Each Group Has (10) Samples. Each Group Was Further Subdivided Into Two Subgroups According To The Type Of Resin Cement, Each Of (5) Samples. Standardized Tooth Preparation Was Carried Out By Milling Machine. Copings Were Fabricated Using Two Types Of Crown Materials: Lava Ultimate CAD CAM Blocks And IPS E.max CAD Blocks. Milled Copings Were Cemented To The Prepared Teeth Using Rely X U200 Self Adhesive Resin Cement And Rely X Ultimate Total Etch Resin Cement. All Samples Were Then Tested For Tensile Bond Strength.

Results: The Effect Of The Variables Combination (type Of Crown Material And Cement Type) On The Tensile Bond Strength Revealed That (Lava Ultimate With Rely X U200 Self-adhesive Resin Cement) Group Produced The Highest Tensile Bond Strength Compared With Combination Groups.

Conclusions: The Retentive Strength Of Lava Ultimate Ceramic Copings When Cemented With Self-adhesive Resin Cement Was The Highest.

Mustafa M. Nour, Ahmed R. Rajab And Ihab B. Almadany,

ABSTRACT


Introduction: Immediate Implant Placement Is Now Accepted In Clinical Dentistry Following A Single Tooth Extraction In The Posterior Maxillary Area.
Objectives: Presenting Stability And Success Rate Of Immediately Inserted Implants At The Site Of Palatal Root Socket Of Maxillary Molar Teeth After Their A-traumatic Extraction, As Well As Patient Satisfaction.

Materials and Methods: We Present The Clinical, Radiographic And Resonance Frequency Analysis Of Implants Placed Immediately In The Palatal Sockets Of Maxillary Molars. Conclusion: Using The Outlined Treatment Approach Of The Present Study Helps Eliminate Many Clinical Compromises Often Encountered When Placing Implants At The Time Of Maxillary Molar Extraction. These Compromises Include Non-ideal Implant Positioning In One Of The Three Extraction Sockets, Maxillary Sinus Pneumatization And Loss Of Ideal Alveolar Ridge Morphology As A Sequelae Of Post-extraction Alveolar Process Resorption.

Nourhan M. Hassan, Kalid A. El Hyes, Nermine Hassanin And Ahmed A. Zaki,

ABSTRACT
Aim Of The Study: Was To Assess The Photochemical Effect Of Low Level Laser Therapy (LLLT) Clinically And Radiographically On Osseointegration Of Dental Implant

Materials and Methods: This Study Included 12 Females With Clinical Diagnosis Of Missing Upper Anterior Or Premolar Teeth Were Divided Into Two Groups. Patients, Divided Into Study Group And Control Group Submitted To Treatment With LLL Using Diode Laser. Study Group Received Six Delayed Implants Were Subjected To LLLT (low Level Laser Treatment) Intraoperatively During Placement Of Dental Implant,while Control Group Received Inactive Laser Using The Same Technique And Schedule As Study Group.

Results: The Results Of This Study Revealed That In The First Interval Of Change (0-3 M) There Was No Statistically Significant Difference Between Both Groups, While In The Second Interval Of Change (3-6 M) Laser Group Showed Statistically Significantly Higher Values Than Control Group.

Abd-Elmotelb MA, Khattab N.M. And Moness A.M.,

ABSTRACT

Objectives: The Purpose Of The Study Was To Evaluate The Efficacy Of Two Different Bleaching Agents (Hydrogen Peroxide 10% Versus Carbamide Peroxide 10%) For Internal Bleaching Of Primary Teeth.

Materials and Methods: Thirty Extracted Human Primary Anterior Teeth With Intact Crowns Were Selected For The Study. Pulpectomy Was Performed And Baseline Color Evaluation With Spectrophotometer And Visual Method Was Obtained Then Each Tooth Was Artificially Stained With 2 Ml Of Fresh Rabbit Blood And Centrifuged. The Teeth Were Randomly Divided Into Three Experimental Groups Of 10 Teeth Each. 0.04 Ml Of The Each Tested Bleaching Agents Was Syringed Into The Access Cavity Of Each Tooth And, In The Control Group, 0.04 Ml Of Distilled Water Was Syringed Into The Access Cavity. Access Cavities Were Sealed With IRM. All Teeth Were Placed At 37�C In An Incubator Throughout The Experiment. The Color Of The Bleached Teeth Was Determined At 0,7 And 14 Days For Spectrophotometeric Evaluation And 0,3,7,10 And 14 Days For Visual One. The Data Obtained Were Collected, Tabulated And Subjected To Statistical Analysis Using Mann-Whitney Test.

Results: There Was Statistical Significance Among The Hydrogen Peroxide And Carbamide Peroxide Versus Control Groups Either Using Spectrophotometer Or Visual Evaluation (P=0.001). Also, There Was Significance Between Hydrogen Peroxide Versus Carbamide Peroxide At Different Observation Periods. Conclusion: The Bleaching Efficacy Of 10% Hydrogen Peroxide Gel Was More Effective Than 10% Carbamide Peroxide In Bleaching The Artificially Discolored Primary Teeth.

Hisham A. A. Qais, Hamdy A. M. Marzook And Rehab Rizk Abas El Zehary,

ABSTRACT

Objectives: This Study Was Designed To Evaluate The Influence Of Bisphosphonates And Antioxidants On Bone Healing Histologically After Surgical Defect Of Bone Tissue In Rabbits. Methods: A Total Of 60 Rabbits Were Randomly Divided Into Three Main Equal Groups: One Control Group And Two Study Groups. Three Circular 5 Mm Diameter Bony Defect Were Subjected At The Medial Surface Of The Proximal Right Tibia Using A Trephine Bur. The Bone Defects Were Left Empty (control Group, N = 20), Animals Were Treated With 0.1 Mg/kg Zoledronic Acid (Zometa) (study Group 1, N = 20), Treated With 0.1 Mg/kg Zoledronic Acid (Zometa) And Vitamin C (Cevarol) (study Group 2, N = 20). Each Group Was Divided Into 4 Subgroups (A, B, C, And D) According To The Period At Which The Animals Were Sacrificed (1, 3, 5, And 7 Weeks Respectively) For The Study And Control Groups. The Specimens Were Evaluated By Histology And Histomorphometric Analysis.

Results: There Were Highly Significant Differences Between The Groups Regarding To Amount Of Bone Formation At Different Periods Of Follow Up Either 1st, 3rd, 5th, Or 7th Weeks (P ? 0.001). Also, There Were Significant Differences Between Intra- Group Distributions Concerning To Amount Of Bone Formation At Different Periods Of Follow Up Either 1st, 3rd, 5th, Or 7th Weeks ( P1, P2, And P3 ? 0.001). Conclusion: In The Current Study It Was Found That, Proper Application Of Bisphosphonates And Antioxidants Managements, A Positive Improvement On Bone Tissue Healing Occurred.

Sherifa A. A. Kandil; Mohamed Riad Farid And Shereen Hafez,

ABSTRACT


Aim: Evaluate The Effect Of Different Surface Treatment To Dentin On Shear Bond Strength Of Zinc Modified Glass Ionomer Compared To Nano-filled Resin Modified Glass Ionomer And Assessment Of Tooth Restoration Interface Using Environmental Scanning Electron Microscope.

Materials and Methods: Zinc Modified Glass Ionomer (Chemfil Rock), Nano-filled Resin Modified Glass Ionomer (Ketac� N100), Dentin Conditioner (Ketac N100 Primer) And Artificial Saliva Solution Was Prepared. Eighty Eight Sound Human Premolars Were Used. Each Tooth Was Individually Embedded Vertically In The Resin Mix; Occlusal Surface Was Grounded Flat Then The Specimens Were Stored In Saline Till The Application Of Different Glass Ionomer. The Two Types Of Glass Ionomer Were Applied With And Without Ketac N100 Primer On The Prepared Specimens Then Shear Bond Strength Test Were Performed At 24 Hours And One Month. The Tested Specimens Were Photographed Using Digital Microscope To Determine Mode Of Failure While For Interfacial Analysis SEM Was Used.

Results: It Was Found That Ketac� N100 Without Dentin Conditioning At 24 Hours Had The Lowest Mean Shear Bond Test (SBS) While Chemfil Rock Without Dentin Conditioning At 24 Hours Had The Highest Mean Shear Bond Test. The Predominant Mode Of Failure In All Specimens Was Adhesive Mode Of Failure. SEM Evaluation Revealed A Gap Between Ketac� N100 And Underlying Dentin While No Gap Between Chemfil Rock And Unconditioned Dentin But With Dentin Conditioning A Gap Was Found Between The Ketac N100 Primer And Chemfil Rock

Rofaida Atef Abbas, Ragia Mohamed Mounir And Adel Hamdy Abou Elfetouh,

ABSTRACT


Aim: To Evaluate The Accuracy Of Computer Virtual Reduction Of Mandibular Condylar Fractures Based On Patient Specific Computed Tomography Scan And It�s Impact On The Surgical Procedure. Patients And Methods: Six Patients With Displaced Sub-condylar Fracture Were Treated With Trans-oral ORIF Using Computer Assisted Virtual Planning And Simulation.

Results: The Postoperative Recovery And Healing Phase Was Uneventful In All Patients. The Mean Displacement Of The Condylar Segment Was Found To Be 3.5 Mm With Standard Deviation Of 0.2 Mm In The Axial Dimension. In The Coronal Dimension, The Mean Displacement Was Found To Be 0.7 Mm With Standard Deviation Of 0.08 Mm. In The Sagittal Dimension, The Mean Displacement Was Found To Be 2.8 Mm With Standard Deviation 0.4 Mm. Conclusion: The Surgical Treatment Of Sub-condylar Fractures Of The Mandible With The Trans-oral Approach Using Computer Assisted Virtual Planning And Simulation Offers Reliable Clinical Results And Accurate Anatomical Reduction.

Mohamed Kadry Nasr Geaisa, Hesham Abdelhakam And Adel Hamdy Abouelfetouh,

ABSTRACT


Aim: To Evaluate The Validity And Reliability Of The Computer Virtual Reduction For Anterior Mandibular Fractures Based Upon Patient Specific Computed Tomography Scan. Patients And Methods: A Total Of Nine Patients With Anterior Mandibular Fractures Were Treated With Open Reduction And Internal Fixation Using Computer Assisted Virtual Planning And Simulation.

Results: All Nine Patients Showed Uneventful Healing. Acceptable Fracture Reduction In Correlation With The Planed Virtual Reduction. The Mean Displacement Of The Proximal Segment At The Mental Foramen Was Found To Be 2.3 Mm With Standard Deviation Of 0.12 Mm In The Axial Dimension. In The Coronal Dimension, The Mean Displacement Was Found To Be 0.98 With Standard Deviation Of 0.41 Mm. In The Sagittal Dimension, The Mean Displacement Was Found To Be 1mm With Standard Deviation 0.9 Mm. Conclusion: Preoperative Simulation And Visualization Can Be A Valuable Tool In Planning Of Craniofacial Surgery And Reducing The Operating Time And The Accuracy Of The Final Reduction.

Tarek F. Mounir, Mohammed F. Abdallah And Amal F. Kaddah,

ABSTRACT

Objectives: The Aim Of This Study Is To Compare The Electromyographic Muscle Activity Of Both The Buccinator And Temporalis Muscles In Patients Wearing Implants Supported Mandibular Over-dentures Using Two Different Types Of Attachments Namely: A) Bar Attachments. B) Magnet Attachments.

Materials and Methods: Ten Patients Were Selected Having Completely Edentulous Upper And Lower Arches, Divided Into Two Groups, Group A Having Implant-supported Mandibular Overdenture With Bar Attachment And Group B Having Implant-supported Mandibular Overdenture With Magnetic Attachment. In Both Groups, The Implants Were Placed In The Canine Region, Muscular Evaluation Was Performed In Each Phase During The Study By Using A Digital Electromyogram (EMG)* Muscular Activity, Represented By The Root Mean Square Value (RMS), Was Evaluated.

Results: The Data Obtained From The Present Study Showed That There Was No Significant Difference Between Bar And Magnet Attachments According To Muscular Activity Measured. Conclusion: Within The Limitations Of This Study, It Was Concluded That: In Elderly Patients, The Treatment With 2 Inter-foramina Implants Provides Evidence Of Neuromuscular Adaptation Towards Values Of Healthy Dentate, Thus The Known Benefits Of Implant Placement Such As Tissue Perseverance And Improved Function Are Complemented By Improved Neuromuscular Adaptation. II. There Was No Significant Difference Between Bar And Magnet Attachments Regarding The Muscular Activity Measured.

Ahmed Mohamed Amer, Ahmed Gamal Hamzawi And Emad MT Mahmoud Agamy,

ABSTRACT
Objective: The Aim Of This Study Was To Compare The Effect Of The Implant Position On Stress Distribution In Bilateral Distal Extension Free End Saddle (Kennedy Class I), Through Three-dimensional Finite Element Analysis (3D FEA). Method: A 3D Finite Element Model Of Mandibular Bilateral Distal Free End Saddle RPD Was Established, Using Single Implant For Support. Three Variant Implant Positions Were Studied; At The Position Of The 2nd Premolar, 1st Molar, And 2nd Molar. Unilateral Vertical Load Of (150 N) Was Applied And Distributed On The Central Fossae Of Posterior Teeth On The Right Side. The Biomechanical Behaviours Of Peri-implant Bone, Implant, Mucosa And Overdenture Were Recorded At Each Situation.

Results: The Highest Stress On Implant And The Surrounding Structures Was In The 2nd Premolar Area. The Best Stress Readings Of The Implant And The Surrounding Structures Were At The 2nd Molar Region, Except For The Periodontal Ligament Buccal Of The Right Canine; At The Same Side Of Load Application. No Overloading Was Recorded At Any Of The Supporting Structures. The Maximum Stresses Occurring At Any Part Were Less Than The Yield Strength Of The Respective Material And Within The Biological Range. Conclusion And Clinical Significance: Within The Limitations Of The Current Study; It Could Concluded That The Best Implant Location For Implant Assisted Bilateral Long Span Distal Extension RPDs, Regarding Stress Distribution, Would Be The 2nd Molar Region. Additional Research Is Recommended And Further Verification Should Be Carried Out In Clinical Cases In Order To Gain A More Accurate Clinical Guidelines.

Ehab Ahmed Farghaly, Ahmed Hassanien, Zahrah Eldawakhly And Tamer Mounir Nassef,

ABSTRACT
This Study Evaluates The Effect Of Connector Design, (radii Of Gingival Embrasure Angel 0.5 And 1 Mm), And The Veneering Techniques, (Press- On And CAD-On), On The Biomechanics Of Implant Supported Three Units Posterior All Ceramic FPD. A 3-dimentional Finite Element Models Were Constructed Representing Two Implants Together With Implant Abutments Which Were Positioned In Place Of Missing Lower Second Premolar And Second Molar In A An Epoxy Resin Full Arch Model. A Three Unit FPD Virtually Constructed Using IPS E.max ZirCAD Blocks, With A Framework 0.5 Mm Radii Of Curvature At The Gingival Embrasure Of The Connector And Another Framework With 1 Mm Radii Of Curvature At The Gingival Embrasure Of The Connector With The Two Veneering Techniques: Press-on And Cad-on Which Were Virtually Placed Over The Implant Fixtures. Load Was Virtually Applied At The Gingival Fossa Of The Pontic Similarly To The Mechanical Testing And Stresses Were Analyzed. For The Cad- On Group It Was Found That 0.5 Mm Connector Recorded Higher Von Misses Stresses Mean Value (26.37 MPa) Than 1 Mm Connector Mean Value (21.25 MPa). For The Press- On Group The 1 Mm Connector Recorded Lower Von Misses Stresses Mean Value (22.84 MPa) Than 0.5 Connector Mean Value (27.25 MPa). With 0.5 Mm Connector Curvature Design; It Was Found That CAD On Group Recorded Lower Von Misses Stresses Mean Value (26.37MPa) Than Press On Group Mean Value (27.25 MPa). And With 1 Mm Connector Curvature Design; It Was Found That Press On Group Recorded Higher Von Misses Stresses Mean Value (22.84 MPa) Than CAD On Group Mean Value (21.25 MPa). It Was Concluded That The Design Of 1 Mm Gingival Connector Curvature Radii Showed Higher Load To Failure When Compared To The 0.5mm Gingival Connector Curvature Radii Design, And CAD-on Veneering Technique Has Higher Mean Fatigue Failure Than The Press-on Veneering Technique.

Sarah M.S., Amr H. El-Bolok And Enas A.A.,

ABSTRACT
Aim Of Study: To Evaluate The Expression Of Growth Factor Receptor Bounded Protein 2 (Grb2) And Human Epidermal Growth Factor Receptor2 (HER2) In Keratocystic Odontogenic Tumor (KCOT).

Materials and Methods: 30 KCOT Paraffin Blocks Were Stained Immunohistochemically For Grb2 And HER2. Immunostaining Was Measured As Area Fraction And The Results Were Analyzed Statistically. P Value < 0.05 Was Considered Significant.

Results: All Cases Of KCOT Showed Positive Nuclear And Cytoplasmic Reaction For Grb2 And Nuclear Reaction For HER2. A Significant Positive Correlation Was Found Between HER2 And Grb2 Expression In KCOT. Conclusion: HER2 And GRB2 Play A Significant Role In The Proliferation, Pathogenesis And Progression Of KCOT. Grb2/HER2 Signaling Pathway Plays A Role In The Pathogenesis Of KCOT.

Lamia N. Metwally , Mokhtar N. Ibrahim , Omaima H. Ghallab And Amin E. Amin,

ABSTRACT

Objectives: To Evaluate The Effect Of Different Doses Of Ionizing Radiation And Storage Times On The Microleakage Of Two Different Types Of Glass Ionomer Restorative Materials; Conventional And Resin Modified.

Materials and Methods: Standardized Cylindrical Class V Cavities Were Performed In 80 Bovine Incisors. Teeth Were Divided Into Two Main Groups According To The Type Of The Glass Ionomer Material Used Restoring The Cavities; Conventional Or Resin Modified (n=40). Both Groups Were Further Divided Into Four Subgroups According To Irradiation Dose; Zero Gray (control Group), 10 Gray, 30 Gray And 60 Gray (n=10). Each Group Was Measured For Microleakage At Three Time Intervals; 3 Weeks; 6 Weeks And 12 Weeks After The End Of The Radiation Exposure. Microleakage Testing Was Performed Using Fluid Filtration Device. Values Of Microleakage In �l/min/20 Psi Were Collected, Tabulated And Statistically Analyzed. Data Was Presented As Mean And Standard Deviation Values, The Significant Level Was Set At P ?0.05.

Results: Mixed Model ANOVA Showed That The Groups Of (control And 10 Gray) Had Statistically Significant Lower Microleakage Values Than (30 Gray And 60 Gray) Groups (p<0.05). There Was A Statistical Significant Effect Of The Type Of Glass Ionomer On The Microleakage. The Interaction Between The Storage Times, The Type Of Glass Ionomer And The Irradiation Doses Was Only Significant In 60 Gray Group P=0.038 For The Conventional Glass Ionomer Group And P=0.014 For The RMGI Group).

Conclusions: Within The Limitations Of This Study, It Was Concluded That: The Time Of Storage Didn�t Have Any Influence On The Microleakage Of Class V Glass Ionomer Restorations. The Variation Of The Chemical Composition Of Glass Ionomer Affected The Microlekage Of Class V Glass Ionomer Restorations And The High Therapeutic Radiation Doses Had A Direct Effect On The Microleakage Of Class V Glass Ionomer Restorations.

Omaima H. Ghallab , Rana A. Sedky And Amin E. Amin,

ABSTRACT

Objectives: The Aim Of This In Vitro Study Was To Evaluate The Effect Of Different Doses Of Ionizing Radiation On The Microleakage Of Tooth/resin Composite Restoration Interface Using Qualitative And Quantitative Methods.

Materials and Methods: Standardized Cylindrical Class V Cavities Were Prepared On The Labial Surfaces Of 40 Extracted Bovine Permanent Incisors. The Teeth Were Randomly Divided Into 4 Groups (n=10) According To The Irradiation Dose Received In Gray (Gy); (zero, 10Gy, 30 Gy& 60 Gy). The Cavities Were Restored With Resin Composite (Artiste) Using A Solvent-free Self-etching Adhesive (Bond 1 SF). After Restoration Of The Prepared Cavities, The Irradiation Doses Were Delivered As One Shot. All Specimens Were Stored In Distilled Water For Six Months Till Testing For Microleakage Using Fluid Filtration System And Dye Penetration Method. Data Was Analyzed Using One-way ANOVA, Kruskal-Wallis, Mann-Whitney And Spearman�s Correlation Tests.

Results: No Statistical Significant Effect Of Different Radiation Doses On Microleakage (P> 0.05) By Fluid Filtration Method. Dye Penetration Showed A Highly Statistical Significant Difference Between The Non-radiated And Radiated Groups (P <0.05). Fluid Filtration And Dye Penetration Assessments Showed A Weak And Non Statistical Significant Correlation.

Conclusions: Within The Limitations Of This In-vitro Study, It Was Concluded That: The Effectiveness Of Interface Assessments; Qualitative And Quantitative Seemed To Be Same. The Grays Of Ionizing Radiation Doses Did Not Affect The Interface Profile Regarding The Microleakage Assessment. The Time Elapsed In The Test Played A Great Role In Data Registration-criticism.

Eman M. Raffat , Ahmed K. Khalifa And Moustafa Abdou Elsyad,

ABSTRACT


Aim: This Study Aimed To Evaluate And Compare The Retention Of Telescopic And Milled Bar Attachments For Four Implant Supported Maxillary Overdenture.

Materials and Methods: An Acrylic Resin Model Of An Edentulous Maxilla Without Alveolar Undercuts Was Fabricated And Four Laboratory Implants Were Inserted In The Canine And Second Premolar Areas. Mucosal Simulation Was Fabricated Over The Model. Maxillary Experimental Overdenture Were Constructed Over The Model And Connected To The Model With Either Telescopic (group I) Or Milled Bar Attachment (group II). The Universal Testing Machine Was Used To Apply Vertically Oriented 4 Points Tensile Loads On A Metal Plate Attached To The Model With 4 Metal Chains Until The Attachments Separated From The Abutments. Maximum Load Needed To Dislodge The Experimental Overdenture From The Maxillary Test Model (retentive Force) Were Calculated. Initial Retentive Forces And Retentive Forces After Repeated Insertions And Removals (540 Cycles) Were Calculated.

Results: Milled Bar Attachment Recorded The Highest Initial And Final Retentive Forces, While Telescopic Attachment Recoded The Lowest One.

Conclusions: Milled Bar Attachment Recorded Significant Higher Retention Compared To Telescopic Attachment.

Hosny N S, Negm M M And Ghoneim A G,

ABSTRACT


Aim: The Aim Of This Study Was To Evaluate And Compare Smart Paste Bio Sealer With AH Plus Sealer Regarding The Push-out Bond Strength After Various Irrigation Protocols (95% Ethanol, Distilled Water, 5.25%NaOCl And QMix 2 In1).

Materials & Methods: Forty Extracted Single Canalled Maxillary Incisor Human Teeth Were Standardized To 15 Mm Length And Mechanically Instrumented Using ProTaper Universal Rotary Files To File Size F4. The Roots Were Randomly Divided Into Two Groups (n=20) According To The Filling Material Used. Group 1 (Smart Paste Bio+Propoint F4) And Group 2 (AH Plus+gutta Percha F4). Each Group Was Subdivided Into Four Subgroups (n=5) According To The Final Irrigating Solution Used Before Obturation. Subgroup A: 2ml Of 95% Ethanol. Subgroup B: 2 Ml Of Distilled Water. Subgroup C: 2ml Of 5.25% NaOCl. Subgroup D: 2ml Of QMix 2in 1. The Specimens Were Obturated With The Single Cone Technique. Then The Roots Were Sectioned Into Three Horizontal Sections Of 2 Mm Thickness, Cut From Coronal, Middle And Apical Thirds Of Each Root. Each Section Was Prepared For Push-out Test Using Universal Testing Machine.

Results: Group 1 Recorded Statistically Significant Higher Push-out Bond Strength Than Group 2. Subgroup C (5.25% NaOCl) Recorded Statistically Significant The Highest Mean Push-out Bond Strength Followed By Subgroup A (95% Ethanol) Followed By Subgroup (B) And (C) Which Recorded The Lowest Push-out Bond Strength Values. Bond Strength Values Were Significantly Higher In The Coronal And Middle Segments In Comparison To Apical Segments. Conclusion: Smart Paste Bio Sealer Produced The Highest Bond Strength Compared To AH Plus Sealer When Single Cone Technique Was Used And Bond Strength Was Differentially Affected By Irrigation Regimens.

Hesham Samy Borg, Hoda Mohamed Amin Rashad, Mohamed Maamoun El-Sheikh And Noha Ossama Abd El-Aziz Issa,

ABSTRACT
Measurements Of Inter Implant Distance Through Two Various Methods Were Evaluated And Compared.

Materials and Methods: Fifteen Completely Edentulous Patientswith Two Mandibulary Inserted Implant Were Selected For This Study. The Distance Between Two Implants Was Measured In The Computerized Way Using Cone Beam Software. The Inter- Implant Distance Was Measured By Clinical Way Using Digital Caliper. The Data Gained By 2 Ways Of Measurements Were Compared.

Results: The Calculated Mean Of Clinically Measured Inter-implant Distances Was (25.149� 4.9244) While Cone Beam Measurements Of Inter Implant Distancewas (25.375� 4.7777) Of The Same Distance Revealing No Significant Difference Between Both Method. Conclusion: No Significant Differences Between Inter Implants Distances By Using Clinical Measurements Distances And Post-operative Distances On The Cone Beam.