Sally Mansour, Dina F. Ahmed And Mohamed M. Elsorougy,

ABSTRACT

Objectives: Assement Of Accuracy Of Maxillary And Mandibular Angular Measurements Using Varying Electric Potential Difference (kVp) In Comparison With Real Measurements. Methodology: In This Study, 23 Skulls Were Used. 2 Angles Were Measured For Each Side. The First Angle To Be Measured Was The Angle Of The Mandible, Which Is The Angle Formed By The Intersection Of The Posterior Border Of The Ramus With The Inferior Border Of The Mandible. The Second Angle Was The Angle Formed By The Intersection Of The Zygomatic Arch And The Temporal Process Of The Zygomatic Bone. The Skulls, Attached To Their Mandibles, Were Radiographed Using Planmeca ProMax 3D Mid CBCT Machine Using 8 MA, (?20cm X 17 Cm) Field Of View (FOV) And 400 �m Voxel Size At An Exposure Time Of 27 Seconds, With 3 Different KVp Settings 90, 80 And 60. Real Measurements Were Performed Using A Goniometer By Two Experienced Radiologists At Two Weeks Interval. Intra- And Inter-observer Agreement Was Assessed By Intra-Class Correlation Coefficient (ICC). Bland-Altman Plot Was Used To Show The Agreement Between Two Quantitative Measurements.

Results: There Was Excellent Inter And Intra-observer Reliability For All Measurements Ranging From- ICC (0.945 To 0.991) Except For A Very Good Agreement Result Of Zygomatic Angle Measurement Using (60 KVp) With Interclass Correlation Coefficient (ICC) (0.896 ). According To Bland-Altman Statistical Test There Was Excellent Correlation Between Measurements At ( 90-80-60 KVp) And Real Measurements . Conclusion: Maxillary And Mandibular Angular Measurements Driven From CBCT Images Of Planameca Promax 3D Mid? Machine Using 60, 80, 90 KVp Are Accurate And Reliable For All Maxillofacial Applications.

Mostafa M.H., Gehan F.M., Emad M.T. And Amr M.I.,

ABSTRACT

Objectives: The Aim Of This Study Was To Evaluate The Stress Distribution In Atrophied Mandibular Ridges By Using Either Implant Supported Over Denture With Four Mini Implants Or With Two Conventional Implants Through A Finite Element Analysis Method.

Materials and Methods: Three Dimensional Finite Element Analysis Was Used To Compare The Stresses In Mandibular Full-arch Implant-supported Over Dentures Loaded By Simulated Biting Force. A Finite Element Model Derived From An Edentulous Human Mandible With Resorbed Ridge Was Constructed. The Model Was Duplicated Into Two Identical Models Which Were Restored With Implant Supported Mandibular Over Dentures Supported By: Model A; Two Intra-foraminal Standard Diameter Implants And Model B; With Four Mini Implants. A 450-N Load For Each Side Was Applied On Maximum Intercuspation Areas On All Mandibular Arch Teeth.

Results: Model B Showed The Highest Amount Of Stresses On The Peri-implant Bone. While Model A Showed An Approximately 27% Stress Reduction. The Stresses On The Implants Showed Slight Increase In Model A By 1.07%. Conclusion: In Case Of Resorbed Ridge, Using Two Conventional Implants Cause Less Stresses Than Using Four Mini Implants In The Peri-implant Bone While Not Harming The Implants.

Mohammed A. Khafagy , Medhat A. Kataia And Abd El Gawad RA,

ABSTRACT
The Present (in Vitro Study) Aimed To Evaluate Calcium Hydroxide Intracanal Medication Remnants After Removal By Two Methods Of Irrigation: Conventional Irrigation And Navitip FX Brush And The Effect Of The Remnants On The Adaptability Of Two Root Canal Sealers: AH Plus And MTA Fillapex. Seventy Sound Human Freshly Extracted Single Rooted Teeth Were Collected, Randomly Classified After Cleaning And Shaping Into Two Main Groups Group A (n=50): Root Canals Were Filled With Injectable Calcium Hydroxide, Group B (n=20): Root Canals Were Sealed Empty Without Calcium Hydroxide Intracanal Medication (control Group). Samples Of Group A Were Subdivided Into Two Subgroups (n=20); SubgroupA1 (calcium Hydroxide Removed With Conventional Irrigation), Subgroup A2 (calcium Hydroxide Removed With Navitip FX Brushes). Group B And Subgroups A1, A2 Were Subdivided Into Two Divisions (n=10); Divisions B�, A1� And A2� AH Plus Sealer Used For Root Canal Obturation, Divisions B?, A1? And A2? MTA Fillapex Sealer Used For Root Canal Obturation. After Removal Of Calcium Hydroxide Remnants Evaluation Was Done By EDAX (energy Dispersive X-ray Micro-analyzer). After 7 Days From Root Canal Obturation, Samples Were Checked Under SEM To Evaluate Sealing Ability Of Tested Root Canal Sealers. Results Regarding Amount Of Calcium Hydroxide Remnants After Removal By The Two Techniques Showed That Conventional Irrigation Removed Calcium Hydroxide Slightly Higher Than Navitip FX Brushes. Results Regarding The Adaptability Showed That AH Plus Is Better Than MTA Fillapex In The Control Group (without Ca(OH)2, However AH Plus Showed Slightly Better Sealing Ability Than MTA Fillapex In The Presence Of Ca(OH)2 Remnants.

Mohamed S. Othman, Manal R. Hassan And Mohamed M. Shalaby,

ABSTRACT

Objectives: A Recently Introduced Pre-sintered Cobalt-chromium (Co-Cr) Alloy For Metal Ceramic Restorations Can Be Efficiently Processed With Computer-aided Design/computer-aided Manufacturing (CAD/CAM) Techniques. However, Little Or No Reliable Study Data Are Available Regarding The Marginal Fit And Bonding Ability Of Porcelain To Milled Co-Cr Alloys In Comparison To Conventional Casting Co-Cr Alloy. Aim Of The Study: The Aim Of This Study Is To Compare The Marginal Accuracy And Shear Bond Strength At The Interface In Porcelain Fused To Metal Crowns Made Of Cast Or Milled Cobalt Chromium.

Materials and Methods: For Marginal Accuracy Test, Twenty Anatomical Crowns (n=20) Were Fabricated Of Commercially Available Cobalt Chromium Alloy, 10 Crowns Constructed Using Conventional Lost Wax Technique Following The Manufacturer?s Instructions, Cast Cr-Co, And 10 Crowns Constructed Using Milling CAD/CAM Technique. The Crowns Were Seated On A Ni-Cr Die Which Was Fabricated After Duplication Of Prepared Mandibular Molar To Receive Cast And/or Milled Co-Cr Full Metal Crowns. After Sintering, Finishing And Polishing Of The Crowns, The Milled And Cast Crowns Were Checked For The Marginal Accuracy Under Scanning Electron Microscope At 75x Magnification. For Shear Bond Strength Test, Twenty Discs (n=20), 8 M Diameter With Thickness 1 Mm Were Fabricated Of Commercially Available Cobalt Chromium Alloy, (cast And Milled) And Will Be Divided Equally Into 2 Groups: 10 Discs Of Cast Co-Cr And 10 Discs Of CAD/CAM Milled Co-Cr .after Sintering And Polishing Of The Discs, Dental Ceramic Veneer 6 Mm In Diameter With Thickness 1 Mm Were Fused To The Cobalt Chromium Alloy Discs Following The Manufacture Instructions. The Veneered Discs Were Subjected To Shear Bond Strength Test By Universal Testing Machine. Data Were Tabulated And Statistically Analyzed With Student T-test Followed By Three Way ANOVA Test. P Values �0.05 Were Considered To Be Statistically Significant In All Tests.

Results: Best Fit Based On The Calculated Means �SD In �m, For All Measurement Points Surfaces Was In The Milled Group (17.55�7.5) While , In The Cast Group Was (19.20�7.8).Yet, Non-significant Differences Were Exist Between Marginal Fit Of Cast And Milled Crowns (p = 0.124) Although, The Two Groups Were Within The Acceptable Range Clinically. As Regarding Porcelain Veneer-metal Interface Bond Strength, Casted Discs Showed A Higher Boning To Porcelain (42.8�9.3) Than Milled Ones (33.8�8.8), (p<0.05). Conclusion: Crowns Produced By Using The Milling Or Sintering Techniques Can Be Considered Clinically Acceptable In Terms Of Marginal Gap And Showed Improved Marginal Fitting Adaptation Than The Conventional Casting Technique. The Bonding Ability, Of The Traditional Casting Produced Alloy-porcelain Veneer Interface, Was Higher Than That Of The Pre-sintered Milled Co-Cr Alloy.

Asmaa Ahmed, Dina F. Ahmed And Nashwa Salah,

ABSTRACT

Objectives: Evaluate The Diagnostic Accuracy Of Planmeca ProMax 3D Mid CBCT Unit With Different Voxel Sizes (0.075 Mm, 0.2 Mm, And 0.4 Mm) In Detection Of Second Mesiobuccal Canal In Maxillary Molars As Compared To Clinical Sectioning Of The Tooth (gold Standard).

Materials & Methods: This Study Was Performed On Twenty Four Maxillary Molars Fulfilling The Inclusion Criteria. The Molars Were Inserted In Acrylic Models, With Six Teeth Embedded In Each Model Using Inlay Wax For Support. The Acrylic Cast Was Placed In A Plastic Container Filled With Water To Simulate The Soft Tissues. All Acrylic Casts Were Scanned Using Planmeca ProMax 3D Mid CBCT Machine (Helsinki, Finland). All Molars Were Radiographed Using Three Different Voxel Sizes (0.075 Mm, 0.2mm & 0.4mm). After That, The Scans Were Assessed By Two Radiologists Twice With Two Weeks Interval For Inter And Intra-observer Agreement. The Reference Standard In This Study Was The Clinical Sectioning Of The Second Mesiobuccal Root Using The Bronwill Microtome. The Mesiobuccal Root Was Cut Into Two Sections And Visually Evaluated. All Data Were Collected, Tabulated And Subjected To Statistical Analysis.

Results: From The 24 Maxillary Molars, 13 Had Two Mesiobuccal Canals After The Analysis Of The Transverse Sections (gold Standard). The Results Of This Study Revealed That The Sensitivity, Specificity And Accuracy Of CBCT Images Increase As The Voxel Size Decrease. However, Statistical Analysis Showed That There Was No Statistical Significant Difference Between The Three Voxel Sizes In The Ability To Detect The MB2 Canal (p > 0.05). Inter- And Intra-observer Agreement Showed Very Good Agreement (0.81?1) In The Detection Of MB2 Canal In Maxillary Molars. Conclusion: The Planmeca ProMax 3D Mid CBCT Unit Is Able To Detect The MB2 Canal Of Maxillary Molars Accurately. The Smaller The Voxel Size, The Higher The Image Resolution And Image Quality.

Amira Ragheb, Mona Salah El Din Darhous, Mahmoud Ibrahim El-Refaie, Hanaa M. Elshenawy, Faten Baioumy And Amany Mohy Eldin,

ABSTRACT
Background Laser With Various Wavelength Was Used As An Alternative Treatment To Conventional Periodontal Therapy. The Diode Laser Has Bactericidal And Detoxifying Effect In Periodontal Therapy By Suppressing The Invasive Bacterium Associated With Aggressive Periodontal Disease That Cannot Be Treated With Conventional Scaling And Root Planning (SRP). Objective: This Study Carried Out To Evaluate The Effect Of 970 Nm Diode Soft Tissue Laser On Periodontopathic Bacteria In Patients With Chronic Periodontitis. Subjects And Methods: The Study Carried Out On Twenty Patients Collecting From The (GCF) Into Tubes. Tubes Divided Into Two Groups The First Group Exposed To 970nm With Power 2w With Time Intervals 30 Seconds And 60 Seconds, While The Second Group Was Exposed To 970nm With Power 2.5w With Time Intervals 30 Seconds And 60 Seconds. The Clinical Parameters Were Recorded To Detect The Periodontal Health For Each Patient.

Results: No Difference In Absorbance Unit When Power Is Changed But The Difference Was In The Time Application. The Group Of 2.5w In 60 Seconds Showed Best Antimicrobial Situation. Conclusion: The 970nm Diode Laser With Proper Power And Time Could Be Used As An Adjunctive Treatment With Mechanical Debridement Of Subgingival Pathogenic Microorganisms.

Walid Ahmed Ghanem, Gihan El-Desouky, Mohammed A. Elsholkamy And Sarah Mohamed Wasfi,

ABSTRACT
The Purpose Of This Study Was To Evaluate The Effect Of Beta- Tricalcium Phosphate On The Osseointegration Of Dental Implants Placed Simultaneously With Maxillary Sinus Lift. Patients & Methods: This Study Was Carried Out On 10 Dental Implants Placed Simultaneously With Maxillary Sinus Lift (4 Males And 6 Females) With Average Age 39.9 Years. The Surgical Procedures Were Performed Under Local Anaesthesia. They Included Edentulous Posterior Maxilla With Extensive Pneumatization Of The Maxillary Sinus, Width Of Edentulous Ridge Not Less Than 6mm While Height Of Alveolar Ridge With Minimum Average Bone 5 - 6mm To Allow Initial Stability Of The Dental Implant. Maxillary Sinus Lift Procedure Was Done By Lateral Technique And Dental Implant Was Inserted Simultaneously. Postoperative Clinical And Radiographic Evaluations Were Done For Each Patient After 4 And 6 Months Postoperatively To Detect Bone Density Around The Implant. Implant Stability Was Measured By Osstell Immediately, 4 And 6 Month Postoperatively.

Results: Radiographic Evaluations Revealed That Bone Density Measurements After 6 Months Were Highly Significant Increased More Than After 4 Months Postoperatively. The Implant Stability Measurements After 6 Months Were Increased More Than That 4 Months Postoperatively And Significantly Increased More Than That Immediately Inserted Implant . Conclusion: Beta Tri-calcium Phosphate Graft Increased The Success Rate Of Implant Osseointegration And Stability Following Maxillary Sinus Lift

Mohamed A. Hashem, Olfat S. Hassanein And Mohamed F. Haridy,

ABSTRACT


Aim: This Study Wa Carried Out To Investigate The Ultrastructure Of The ABRZ Formed By Different Adhesive Systems And To Measure The Micro-shear Bond Strength (?SBS) Of Two Self-etch Adhesive Systems, Might Be Of Value.

Materials & Methods: A Total Number Of 64 Extracted Caries-free Human Permanent Molars Were Collected For The Study. Teeth Were Examined And Thoroughly Washed With Water, Scaled With Periodontal Scaler To Remove Any Blood, Attached To Periodontal Tissues, Plaque And Calculus. The Teeth Were Stored In Saline Solution (changed Daily) At Room Temperature Until The Time Of Their Use. The Teeth Were Randomly Divided Into Two Main Groups (32 Each) According To The Adhesive System Used: Fluoride Containing (CLEARFIL Liner Bond F) And Non-fluoride Containing (CLERFIL S3 Bond). Each Group Was Randomly Subdivided Into Two Equal Subgroups (n=16) According To Time Elapsed After Bonding: Immediate After Bonding Or 4 Months Later Each Group Was Later Color Coded Before Storage Step. A Total Of Four Subgroups Were Investigated In This Study. For Each Sub-group, 64 Micro-cylinders On The Occlusal Surface Of Each Specimen Were Prepared For Micro-shear Bond Strength (?SBS) Testing.

Results: ClearFil Liner Bond F (24.4 �4.13 MPa) Showed A Higher Mean Micro- Shear Bond Strength ?SBS Than S3 Bond (19.77�5.96 MPa) With Statistically Significant P �0.001. For Immediate ?SBS ClearFil Liner Bond F Showed High Statistical Values (25.75� 4.71MPa) Than ClearFil S3 Bond Which Showed Mean (24.41� 3.55 MPa) Which Is Not Statistically Significant. For Delayed ?SBS ClearFil Liner Bond F Showed High Statistical Values Of Mean (23.20� 3.16 MPa) Than ClearFil S3 Bond Which Showed Mean (15.14� 3.89 MPa) Which Is Statistically Significant P �0.001. ESEM Scanning Showed A Clearly Recognizable Hybrid Layer, Which Was Thin But Defined, And Continuous. Short Resin Tags Formation With Limited Infiltration Into Dentinal Tubules In Superficial Dentin Conclusion: The Incorporation Of Fluoride Into Self-etch Adhesives Was Advantageous Regarding Immediate And Delayed Bond Strength. Two-steps Self-etch Adhesives System Provided Superior Bonding Capabilities Compared To One Step Self-etch Adhesives. Fluoride-Containing Adhesives Might Have A Potential Effect On Bond Durability, Via Their Fluoride Release. These Adhesives Can Be Considered Advantageous, And Are Able To Bond Effectively To Dentin.

Mohammad Adnan Alhassan, Gehan Fekry Mohamed, Emad Mohamed Tolba M Agamy And Ahmad Gamal Hamzawy,

ABSTRACT

Objectives: The Aim Of This Study Is To Compare Between Two Different Dental Implant Materials; One Is Conventional Titanium And The Other Is Poly Ether Ether Ketone (PEEK) Material, In Terms Of Stress Distribution Under Simulated Loads.

Materials and Methods: Three-dimensional Finite Element Analysis Method Was Used To Compare The Stresses In Mandibular Full-arch Implant-supported Over Dentures Under Simulated Loading. A 3-D Digital Model Of An Edentulous Human Mandible Was Created From Anonymous Human Dried Mandible. Two Implants Were Drawn In The Canine Region Of The Model That Was Restored By Implant Supported Overdenture. Three Replicas Of The Model Were Created In Which The Only Difference Was The Implant Material. Model A Had Two Conventional Titanium Implants, Model B HadNeat (unfilled) PEEK Implants And Model Chad Carbon Fibers Reinforced (CFR) PEEK Implants. A 450-N Load For Each Side Was Applied On Maximum Intercuspation Areas On All Mandibular Arch Teeth.

Results: Model A Showed The Highest Amount Of Stresses In The Peri-implant Bone; Followed By Model B And Model C Respectively. Stresses Within The Body Of Implant Fixture In Model A Was 212 MPa While In Model B 17.9 MPa And 34.6 MPa In Model C. Conclusion: Using PEEK Implants In Implant Supported Overdenture Produces Less Stresses In The Implant Body And More Homogenous Stress Distribution Within The Peri Implant Bone.

Yomna Hassan Saad, Mahmoud Hamdy Eid And Randa Youssef Abd AlGawad,

ABSTRACT
Objective: To Determine The Prevalence Of Harmful Oral Habits Among A Group Of Egyptian Primary Schoolchildren In Cairo Governorate, Egypt. Subjects & Methods: An Observational, Cross-sectional, Study Was Carried Out Where 624 Students Aged Seven To Ten Years Were Examined For The Presence Of Different Oral Habits. The Study Was Conducted In 4 Egyptian Schools In Abbasia District In Cairo, Egypt. The Presence Or Absence Of An Oral Habit Was Determined By A Clinical Examination Combined With A Questionnaire Filled By Student?s Parents/guardians.

Results: The Prevalence Of Oral Habits Among The Whole Sample Was 60.9%. Nail Biting Habit Was The Most Common Habit 30.9% Followed By Biting On Pens Or Hard Objects 27.2%, Mouth Breathing 18.9%, Cutting Or Opening Objects With Teeth Was 17.6%, Bruxism 13.6%, Lip Biting 11.2%, Digit Sucking 7.5% And Rare Other Oral Habits 1.3% And Tongue Thrusting 0.2 %. Conclusion: Among The Study Sample, The Most Common Oral Habit Was Nail Biting And Tongue Thrust Was The Least Common Oral Habit. The Prevalence Of Any Oral Habit Among The Whole Sample Was More Common In Private Schools In Comparison To Public Schools.