Aya Ezzat ElShimy, Omnia El-Sheihy And Maha Taymour,

ABSTRACT
Statement Of The Problem: Opposite To Silica-based Ceramics, Zirconia Has No Silica In Their Structure, So They Cannot Be Effectively Conditioned Using Hydrofluoric Acid. Zirconia Exhibits Weaker Bond Strength To Resin Than Other Types Of Ceramic Materials, So Repair Of Zirconia With Resin Composite Is Considered To Be Technique Sensitive And Questionable Procedure.

Purpose: The Aim Of This In-vitro Study Was To Assess The Effect Of Two Different Priming Agents On The Shear Bond Strength (SBS) Of Composite Resin Used To Repair Treated Zirconia Compared To Sandblasted Zirconia.

Materials and Methods: A Total Of 24 Zirconia Specimens (12 �10 �3 Mm) Were Sliced From Presintered ICE Zirkon Translucent Zirconia Blank Using An Isomet 98 Cutting Machine Then All The Specimens Were Sintered According To The Manufacturer�s Instructions. The Specimens Were Randomly Divided Into Three Groups According To The Surface Treatment Performed (n=8) : (1) Sandblasting With 110�m Al2O3 Particles (control Group); (2): Chemical Treatment With RelyX Ceramic Primer (RelyX Group); And (3): Chemical Treatment With Monobond Plus Primer (Monobond Plus Group). All Specimens Were Bonded To Two Resin Composite Cylinders With A Universal Adhesive System According To The Manufacturer�s Recommendations. The Samples Were Stored For 24 Hours In An Incubator At 37�C And 100% Humidity, Followed By Thermal Cycling (500 Cycles At 5�C And 55�C). The Shear Bond Strength Was Measured By The Universal Testing Machine With 500 N Load Cell And Speed Of 0.5 Mm/min. Two Representative Specimens Were Randomly Selected From Each Group To Be Examined Using Scanning Electron Microscope X1000 Magnification To Characterize The Surface Morphology Of Each Surface Treatment Method. Mean SBS (MPa) Were Analyzed With One-way Analysis Of Variance (ANOVA) Followed By Pair-wise Tukey�s Post-hoc Tests To Detect Significance Between Groups. Shear Strength Was Calculated Through The Equation: ( T = F (force) / A (area) ).

Results: The Sandblasted Specimens Of The Control Group Showed The Highest Mean Shear Bond Strength With A Statistically Significant Difference While The Specimens Of The RelyX Group Showed Higher Mean Shear Bond Strength Than That Of The Monobond Plus Group With Statistically Non-significant Difference Between Them. The SEM Showed That The Sandblasted Zirconia Had The Roughest Surface With Multiple And Deep Micro-irregularities. While For The RelyX And Monobond Plus Specimens, There Were Mild And Shallow Irregularities.

Conclusions: From The Findings Of Our Study, Sandblasting Of Zirconia With 110�m Alumina Particles Enhances The Shear Bond Strength Of Resin Composite Used To Repair Zirconia-cored Restorations After Chipping Of The Veneer Layer. Sandblasting Has A Better Effect On The Shear Bond Strength Compared To The Chemical Surface Treatment Of Zirconia With RelyX And Monobond Plus Primers. Both Of RelyX And Monobond Plus Primers Have Nearly The Same Effect On The Shear Bond Strength.

Mohamed Fouad El Marakby, Manar Yehia Fouda And Marwa Mahmoud Bedier,

ABSTRACT

Objectives: The Aim Of This Prospective Randomized Clinical Trial Was Compare Between 2% Mepivacaine And 4% Articaine For Inferior Alveolar Nerve Blocks In Patients With Symptomatic Irreversible Pulpitis In Mandibular Molars As Regards To Their Anesthetic Efficiency; During Access Cavity Preparation And Instrumentation. Subjects And Methods: Sixty-six Patients Diagnosed Clinically And Radiographically With Symptomatic Irreversible Pulpitis In Mandibular Posterior Teeth Received Single-visit Root Canal Treatment Using ProTaper Universal Rotary System For Canal Preparation, They Were Randomly Divided Into Two Groups (n=33) According To The Anesthetic Solution Used, Either Group M (3.6 Ml Mepivacaine Hydrochloride 2% With 1:100000 Epinephrine) Or Group A (3.4 Ml Articaine Hydrochloride 4% With 1:100000 Epinephrine). The Pain Was Assessed Using Numerical Rating Scale (NRS) During Access Cavity Preparation And Instrumentation, Then The Need For Supplemental Anesthesia Was Also Recorded.�

Results: There Was No Statistically Significant Difference In Pain Level Between Both Groups At The Different Observation Times. The Success Rates Were Similar In Both Groups (39.4% And 45.5% In Mepivacaine And Articaine Groups Respectively) With No Difference In The Need For Supplemental Anesthesia In Both Groups. Conclusion: The Anesthetic Efficacy Of Mepivacaine And Articaine Seemed To Be Similar, Although Both Did Not Provide Acceptable Rate Of Anesthetic Success.

Randa Abdel Rahman El Naggar, M.Adel Ezzat, M. Fouad Haridy And Shereen Hafez,

ABSTRACT
Objective: This Study Was Carried Out To Evaluate The Effect Of Bleaching On The Colour Change Of Two Types Of Composite Before And After Immersion In Coffee Staining Solutions.

Materials and Methods: A Total Of 144 Specimens Were Prepared In A Circular Teflon Mould (10 X 2mm), Then They Were Divided Into 2 Equal Groups According To Composites Used Amaris And Z350XT , Then They Were Divided To Three Subgroups According To The Bleaching Protocol ; No Bleaching, Bleaching After Staining And Bleaching Before And After Staining And Then Each Group Was Further Divided Into Three Classes According To The Staining Solutions Used ;artificial Saliva, Coffee And Coffee With Sugar And Creamer. Colour Measurements Took Place At Baseline, After Bleaching And After Staining Using X-rite Spectrophotometer According To The CIE L*a*b* Colour Space.

Results: The Results Revealed That Amaris Has The Highest Mean Colour Change, Bleaching Has A Non-significant Effect On The Colour Stability Of Composite Resin But It Can Lighten The Colour Of The Stained Composite And Finally Results Revealed That Coffee Has The Highest Mean Colour Change Among The Used Staining Solutions. Conclusion: Nanofilled Composites Are More Colour Stable Than Nanohybrid Composites, Also Bleaching Is A Viable Option To Remove Extrinsic Stains From Resin Composite.

Walaa Kadry, Mervat El Deftar, Yasmine Nassar And Maha M Hakam,

ABSTRACT
Aim Of The Study: To Clinically And Radiographically (as Regards Bone Density) Assess The Outcomes Of Unilateral Alveolar Clefts Grafted With Tissue Engineered Constructs. Patients And Methods: This Study Was Conducted On Five Patients Presented With Unilateral Alveolar Clefts And Indicated For Secondary Alveolar Bone Grafting. The Alveolar Clefts Were Grafted With Tissue Engineered Constructs Composed Of Osteogenically Differentiated Mesenchymal Stem Cells (MSCs) Derived From The Patient�s Bone Marrow And Loaded On Collagen Scaffolds (Osteovit). Postoperative Clinical Follow-up And A Radiographic 6 Months Postoperative Follow-up Using CT Scan Was Performed At 6 Months Follow Up Period. The Newly Formed Bone Density Was Measured From The CT Scans And Compared To The Native Bone Density On Axial CT Scans.

Results: The Newly Formed Bone Density Was (312.84 HU) Compared To The Native Bone (495.39 HU).

Omneya M. Elkadi, Gihane Gharib Madkour, Hala Salem Elmenoufy And Mahmoud El Refai,

ABSTRACT
Background: There Is Little Number Of Studies That Address The Inter-relationship Of Gestational Diabetes Mellitus (GDM) And Periodontitis During Pregnancy. Hence, This Study Was Conducted To Provide Further Evidence In The Possible Association Between Chronic Periodontitis And GDM By Evaluating The Level Of Tumor Necrosis Factor-alpha (TNF-?) Of Chronic Periodontitis Patients With GDM After Phase I Periodontal Therapy. Subjects And Methods: This Study Was Conducted On 40 Subjects Divided Into 2 Groups: 20 Pregnant Females Suffering From Gestational Diabetes Mellitus Associated With Moderate To Severe Chronic Periodontitis And 20 Systemically Free Pregnant Females Suffering From Moderate To Severe Chronic Periodontitis. The Periodontal Status Of The Subjects Was Assessed At Baseline Before Phase I Periodontal Therapy And 2 Months After Completion Of The Treatment: All Subjects Have Been Screened By Comprehensive Periodontal Examination And Full Periodontal Charts Were Obtained. The Following Clinical Parameters Were Assessed To Determine The Clinical Periodontal Status Of Patients: Plaque Index (PI), Gingival Index (GI), Probing Pocket Depth (PPD), And Clinical Attachment Level (CAL). Gingival Crevicular Fluid (GCF) And Serum Samples Were Collected From Both Study Groups To Detect TNF-? Levels. Regarding The Assessment Of TNF-?, Real-time Reverse-transcriptase Polymerase Chain Reaction (RT) PCR Technique Was Used.

Results: Results Of The Present Study Observed Statistically Significant Reduction In TNF-? Levels After 2 Months From Phase I Periodontal Therapy. The Current Study Showed That, There Was A Statistically Significant Positive (direct) Correlation Between TNF-? Level, PI, GI, PPD And CAL Measurement At Baseline And After 2 Months From Phase I Periodontal Therapy. Conclusion: It Is Shown That The Levels Of TNF-? In GCF And Serum Before Treatment Were Higher In GDM Group (group 1) Than In The Control Group. Thus, The Examination Of TNF-? May Enhance The Understanding Of Pathogenesis Of Periodontitis And GDM And Its Assessment In The Treatment Process May Result In Better Control Of The Disease.

Dina Kamal , Dina Elkassas And Heba Hamza,

ABSTRACT

Objectives: Investigate The Efficacy Of Biomimetic Self-assembling Peptide (P11-4) On Enamel Remineralization Compared To Casein Phosphopeptide Amorphous Calcium Phosphate (CPP-ACPF) And Fluoride Based Delivery Systems. Methods: Artificially Demineralized Enamel Windows Were Created On The Buccal Surfaces Of Forty Extracted Human Molars.. Specimens Were Randomly Assigned To 4 Groups (n=10) According To The Remineralizing Agent Used: G1- (Control, Artificial Saliva), G2- (Fluoride Varnish), G3-(CPP-ACPF Varnish), G4-(Self-assembling Peptide Agent).. All Products Were Applied According To The Manufacturer�s Instructions And Specimens Were Stored In A Daily Renewed Artificial Saliva. Surface Microhardness (SMH) Was Assessed At Baseline, After Demineralization, After 1 Week And 4 Weeks Remineralization.

Results: Self-assembling Peptide Showed The Highest Statistically Significant SMH Followed By Fluoride And CPP-ACPF While The Lowest SMH As Found In Artificial Saliva. However, No Statistically Significant Difference Was Found Between Fluoride And CPP-ACPF. Higher Statistically Significant SMH Was Found After 4 Weeks Compared To 1 Week Remineralization In All Groups.

Conclusions: Self-assembling Peptide Confers The Highest Remineralizing Efficacy Compared To Fluoride And CPP-ACPF; Showing A Promising, Non-invasive Regeneration Potential. Also, Extended Period Of Time Helped To Attain More Benefits From The Remineralizing Regimens Applied.

Mariam Adel Hosny Mohamed, Rasha Mohamed Abdel Raouf And Nour El Din Ahmed Habib,

ABSTRACT


Aim: Investigate Low Temperature Degradation (aging ) Effect Of Three Ceramic CAD/CAM Block Materials: Lithium Disilicate(LD), Translucent Zirconia(TZ) And Zirconia Reinforced Lithium Silicate(ZLD) On Their Flexure Strength.

Materials and Methods: Fourteen Disc Shaped Specimens Were Prepared From Each Material(12mm Diameter And 1.2 Mm Thickness). Seven Specimens Per Material Were Subjected To Low Temperature Degradation. While The Other Seven Were Considered As Control. All Specimens Were Subjected To Biaxial Flexure Strength Testing.

Results: TZ Had The Highest Flexure Strength While There Was No Difference Between The Others. Flexure Strength Of The Three Materials Was Not Affected By Aging

Conclusions: Aging Did Not Affect The Flexure Strength. Translucent Zirconia Has The Highest Flexure Strength While No Difference Between Lithium Disilicate And Zirconia Reinforced Lithium Silicate.

Yasmine Ashraf El Banna, Sherif Bahgat El Taweel And Sara Ahmed Mahmoud,

ABSTRACT


Aim: Testing The Microshear Bond Strength Of Self Adhering Flowable Composite And Conventional Flowable Composite To Dentine Of Primary Teeth.

Materials & Methods: Thirty Sound Human Deciduous Canines Were Collected, The Collected Teeth Were Indicated For Extraction Due To Normal Shedding, Over Retention And Orthodontic Reasons. Teeth Were Assigned Into Three Groups According To The Restorative Materials Used (n=10), Group A: Self Adhering Flowable Composite (Fusio�Liquid Dentin), Group B: Self Adhering Flowable Composite (Fusio�Liquid Dentin) + Self Etch Adhesive (Single Bond Universal), Group C: Conventional Flowable Composite (Filtek� Z350 XT Flowable) + Self Etch Adhesive (Single Bond Universal). Teeth Were Restored For Microshear Bond Strength Testing Then Samples Were Stored In Isotonic Saline Solution For 24 Hours. Then Microshear Bond Strength Was Tested Using Universal Testing Machine; Load Was Applied Till Specimen�s Fail.

Results: Group B Showed The Highest Bond Strength Values While Group A Showed The Lowest Bond Strength Values (P?0.001).

Conclusions: Self Adhering Composite Applied According To Manufacturers� Instructions Produced The Least Bond Strength Values To Dentine Of Primary Teeth. However, Its Bonding Performance Improved Significantly After Preceding It With Self-etch Adhesive System.

Nour Eldeen Mohamed, Layla Mostafa Omara, Mohamed El-Faramawey And Hesham Elsayed Elhawary,

ABSTRACT
Aim Of The Study: The Purpose Of This Study Was To Compare The Survival Rate Of Immediate & Delayed Placement Of Dental Implants, Following Narrow Maxillary Ridge Splitting & Grafting By An Alloplastic Material.

Materials and Methods: The Present Study Was Conducted On 6 Patients Using 16 Implants. The Patients Were Divided Randomly Into 2 Groups, Group I Patients: Eight Sites Were Subjected To Maxillary Ridge Splitting(anterior Region), Ridge Grafting With Hydroxyapatite And Delayed Placement Of Total Number Of Eight Implants While Group II Patients: Eight Sites Were Subjected To Maxillary Ridge Splitting, Ridge Grafting With Hydroxyapatite Followed By Immediate Placement Of Total Number Of Eight Implants. Preoperative, Immediate (one Week), 3 Months And 6 Months Post-expansion And Insertion CBCT Radiographs Assessed For Measuring The Bucco-lingually Width.

Results: During The Follow Up Period, All Patients Showed No Post-operative Complications, Wound Healing Was Uneventful In All Patients, Without Any Signs Of Wound Dehesince Or Infection, All Implants Inserted Were Stable, Which Was Detected By The Periotest. The CBCT Radiograph Showed Proper Contact Between Bone And Implant, Also Showed Increase Buccolingual Width For Both Groups Immediately Post-operative And Decrease In The Width 6 Months Post-expansion And Insertion Of Implants. Conclusion: The Recent Work Has Shown That Ridge Splitting Technique Can Be A Useful Method For Managing The Narrow Maxillary Residual Ridge In Both Groups.

Amr Taha, Ahmed M. Abd Alsamad, Hany Mahmoud Omar And Mushira M. Dahaba,

ABSTRACT

Objectives: Assessment Of The Accuracy Of Linear Measurements In Maxilla Obtained By CBCT Scanner (Planmeca Promax 3D MID CBCT Machine And Software) In Comparison With The Real Measurement Obtained From The Dry Skulls Methods: - The Study Was Performed On Thirty (30) Dry Skulls Obtained From The Anatomy Department Of Faculty Of Medicine, Cairo University. The Skulls Attached To Their Mandibles Were Radiographed Using Planmeca ProMax 3D Mid CBCT Machine. Real Measurements Were Performed Using A Digital Caliper. The Results Obtained Was Subjected To Intra- And Inter-observer Agreement Was Assessed Using Intra-Class Correlation Coefficient (ICC).Bland-Altman Plot (differences-vs-means Plot) Used To Show The Agreement Between Two Quantitative Measurements By Studying The Mean Difference And Constructing Limits Of Agreement .

Results: Excellent Correlation Was Shown Between The Maxillary CBCT Linear Measurements And Real Measurement Obtained From Dry Skulls. There Was Excellent Inter And Inter Observer Reliability. Conclusion:-Maxillary Linear Measurements Driven From CBCT Images Of Planameca Promax 3D Mid� Machine Are Accurate, Reproducible And Reliable For All Maxillofacial Applications.