Ahmed Ebtihag, Lamia Khairalla And Reham Elbasty,

ABSTRACT
Statement Of Problem: Concerns Has Been Raised With Regard To Low Temperature Degradation (LTD) Of Yttria Stabilized Tetragonal Zirconia Polycrystal (Y-TZP) For Monolithic Zirconia And Core Zirconia. However, Studies On Effect Of Low Temperature Degradation On Mechanical Characteristics Of Zirconia Were Insufficient. Aim Of Study: The Aim Of The Study Was To Assess The Effect Of Low Temperature Degradation (LTD) On Flexural Strength Of Monolithic Zirconia And Zirconia Core Using Hydrothermal Aging In Autoclave Condition For 8 Hours (relevant To Around 30 Years Of Clinical Service).

Materials and Methods: 32 Zirconia Discs Were Cut From 2 Zirconia Blocks(monolithic Zirconia And Zirconia Core) With Isomet -1000, Then Were Sintered According To Manufacturer Instructions To Dimensions (12mm Diameter And 1.2 Mm Thickness). Each Group Of Zirconia Was Subdivided According To Hydrothermal Aging Into Aged Subgroups And Non-aged Subgroups. Artificial Aging Was Done In Autoclave Condition At (134?C, 0.2 MPa) For 8 Hours. Non Aged Subgroups Represents Control. X-ray Diffraction (XRD) And Scanning Electron Microscope (SEM) Were Used To Analyze The Microstructure Of Both Y-TZP Types Before And After Aging. All Samples Were Subjected To Biaxial Flexural Strength Test With Ball On Ring In Universal Testing Machine. Data From Biaxial Test Were Analyzed Using Graph Pad Instat (Graph Pad, Inc.) Software.

Results: Zirconia Core Group Recorded Statistically Significant Higher Biaxial Flexure Strength Mean Value (1192.76?105.47 MPa) Than ZrO2 Monolithic Group (1033.13?136.68 MPa) Before Aging. After Aging Zirconia Core Group Also Recorded Statistically Significant Higher Biaxial Flexure Strength Mean Value (1305.52?159.67 MPa) Than Zirconia Monolithic Group (1084.55?91.43 MPa).XRD Analysis Showed Increase Of Monoclinic Content In Both Types Of Zirconia Surfaces After Aging. Conclusion: Hydrothermal Aging Induced Tetragonal To Monoclinic Transformation And Modified The Microstructure Of All Zirconia Types. Moreover, Hydrothermal Aging Didn?t Significantly Affect The Flexural Strength Of Monolithic And Core Y-TZP After 8 Hours Of Aging Within The Limitations Of This Study. Also, Both Monolithic Zirconia And Core Zirconia Can Resist Low Temperature Degradation Up To 24-32 Years Of Clinical Service.

Esraa Ali Mahmoud Bersy, Seham Ahmad Abdel Ghani And Houry Moustafa Baghdadi,

ABSTRACT
Aim And
Objectives: The Aim Of The Present Study Is To Introduce A Novel Modality For Estimation Of The Anti-neoplastic Efficacy Of Chemotherapeutic Agents And To Compare This Technique With The DNA Fragmentation Assay. Methods: Squamous Cell Carcinoma Cell Line HEp-2 Was Used In The Present Study. The Cytotoxic Drug Used In This Study Was Sesamol. Microscopic Slides Of Each Drug Concentration At Definite Post-treatment Durations Were Photomicrographed And Analyzed Using Image Analysis Software For The Estimation Of Nuclear Area Factor. Data Were Then Statistically Analyzed. To Assess Whether The Morphological Changes Induced By The Drug Depended On Activation Of The Apoptotic Pathway, It Was Investigated Whether It Could Induce Internucleosomal DNA Fragmentation.

Results: The Data Recorded Revealed A Decrease In The Mean Values Of NAF Of HEp-2 Cells Treated With Different Concentrations Of Sesamol Over Different Durations When Compared To Control Cells. DNA Fragmentation Was Not Observed In The Control Groups Over Different Durations Of Incubation. The Study Of Internucleosomal DNA Fragmentation In HEp-2 Cells Treated With Different Concentrations Of Sesamol Over Different Durations Revealed Absence Of DNA Laddering That Indicated DNA Fragmentation With 6.25 ?M Sesamol Concentration After 24 Hours Of Incubation. Conclusion: The Present Data Suggested That Estimation Of Nuclear Area Factor Is A Sensitive Predictor Of Early Apoptotic Effect Of Anti-cancer Therapy. DNA Fragmentation Assay Is A Useful Tool For Detection Of Late Apoptotic Changes That Discriminates Apoptotic Effects Of Anti-cancer Drugs From Necrotic Ones.

Mohamed Riyad AlShikh, Sanaa Soliman Abouzeid, Eman Mohie-Eldin And Rayan Almurtada,

ABSTRACT


Introduction: Effect Of Extraction On The Orthodontic Practice Was Claimed To Cause Decrease In The Airway Diameter And Affect The Hyoid Bone Position. Other Researchers Contradicted This Finding. The Aim Of The Study Was To Systematically Review The Literature To Resolve This Conflict.

Materials and Methods: The Study Included The Clinical Trials, Cohort Studies, Published And Unpublished Thesis And Literature. The Data Bases Searched Included Pubmed, Cochrane, LILACS, And Grey Literature Until 31/12/2017. Total Records Included 1139 Articles. The Participants Were At Least 15 Years Old, With And Pre And Post Cephalometric Radiographs Or CT Scans And Undergone First Premolar Extractions.

Results: Only Two Studies Included The Qualitative Synthesis. Conclusion: The Studies Showed The Orthodontic Extraction Changed The Hyoid Bone Position.

Ahmed Nabil Fahmi, Hanan Eid, Amr H. Gibaly And Mohamed Mostafa Elshamaa,

ABSTRACT
Dermoid Cysts Are Soft Tissue Cysts Of Embryonic Origin That Arise Along Lines Of Skin Fusion. They Formed Due To Abnormal Ectodermal Sequestration During Early Embryological Life. The Variable Types Of Craniofacial Dermoid Cysts May Be Related To The Initial Position Of Ectodermal Inclusion Within The Underlying Mesoderm. Variations In The Degree Of Ectodermal Inclusion Result In Differences In The Histology And Structure Of Dermoid Cysts At The Various Craniofacial Sites. Such Histologic Differences May Directly Influence The Severity Of Clinical Presentation. Five Cases Of Periorbital And Submental Dermoid Cysts Were Operated On Under General Anesthesia; All Cases Were Subjected To Immunohistochemical Staining With Cytokeratin, Vimentin And Chromogranin. There Was Significant Correlation Between The Expression Of Chromogranin In Periorbital And Submental Dermoid Cysts (P=0.007), While There Was Nonsignificant Correlation Between The Expression Of Cytokeratin In The Two Lesions (P= 0.08) And Also Nonsignificant Correlation Between The Expression Of Vimentin In The Two Lesions (P=0.43). Objective To Differentiate Histologically And By Using Immunohistochemitry Between Submental And Periorbital Dermoid Cysts.

Yasmin Hefnawy, Jylan Fouad El-Guindy And Lamyaa Khair Allah,

ABSTRACT
The Aim Of This Study: Was To Measure The Fracture Resistance In Endodontically Treated Teeth Restored With Lithium Disilicate Crowns Retained With Fiber Posts And Core Compared To VITASUPRINITY And CERASMART Endocrowns. Statement Of The Problem: The Risks That Increased The Potential Of Tooth Fracture After Endodontic Treatment, The Risks Included Loss Of Tooth Structure, Post Canal Preparation, Post Selection. Endocrowns Were Revealed To Fail More When Fixed To Premolars. The Influence Of Different Crown Material On Fracture Resistance Of Ceramic Crowns Placed On Endodontically Treated Maxillary Premolars Has Not Been Clearly Established. RESEARCH QUESTION: In Endodontically Treated Maxillary Premolars Will Teeth Requiring (VITASUPRINITY) And Hybrid Ceramics (CERASMART) Endo Crowns Provide Better Fracture Resistance Compared To Lithium Disilicate Ceramic Crowns Retained With Glass Fiber Posts? Hypothesis: 1. Endo-crowns Will Have More Fracture Resistance Than Lithium Disilicate Crowns Retained With Fiber Postsand Composite Core. 2. Endocrowns Restoration Made Of VITASUPRINITY Material Would Show More Fracture Resistance Than Endocrowns Made Of Hybrid Ceramics CERASMART. Conclusion: 1. Both VITASUPRINITY And CERASMART Endocrowns Are As Promising As Fiber Post And Composite Core Supported IPS E.max CAD Crowns. 2.Favourable Mode Of Fracture Of VITASUPRINITY, CERASMART Endocrowns And Fiber Post And Composite Core Supported IPS E.max CAD Crowns Since The Fracture Was Mostly Above CEJ ?repairable?. 3. All Fracture Resistance Loads Obtained Were Far Beyond The Maximum Masticatory Forces, Which Can Withstand The Maximum Intraoral Masticatory Forces In The Maxillary Premolar Region.

Rana A. Abdulatif And Cherif A.Mohsen,

ABSTRACT
Objective: The Aim Of This Study Is To Evaluate In An In Vitro Study, The Influence Of Straight And Angulated Implant In Lower First Molar And Upper Central Incisor On The Fracture Resistance And Failure Location Of Zirconia Crowns Fabricated Using CAD\CAMtechnology.

Materials and Methods: In This Study 20 Casts Were Used , Epoxy Resin Mixed And Loaded In The Sockets, Then Implant Was Loaded And Fixed Into All 10 Missed Lower Molar And 10 Upper Central Incisor. According To Position Of Implants The Samples Divided Into Two Groups Anterior And Posterior. Each Group Divided Into 2 Subgroups (5 Samples Each) According To The Degree Of Abutment Angulation Straight Abutment And 15 Degree Angulation. The Specimens Were Then Subjected To Compressive Loading By Universal Testing Machine (Shimadzu Autograph AG-50kNE, Shimadzu Co., Ltd, Japan) . The Force Required (N) To Cause Fracture Of The Crown, And The Mode Of Failure Were Recorded Using A Classification Designed For The Investigation.

Results: The Mean Values ?SD Of Loads At Failure (n -5) For Each Group Were As Follows In Newton (N): Posterior Straight Angle (A- I) 1361.6?245.3-,posterior 15 Angulation,(A-II) 1820.6?168 , Anterior Straight Angulation(B-I) 1117.5?112, Anterior 15 Angulation (B-II) 1435?135.9 0There Was Significant Increase In The Maximum Resistance At Angle 15 Compared With Angle 0 At Anterior E And Posterior Site.(p<0.05). Conclusion: Within The Limitations Of The Invitro Study, The Following Can Be Concluded: (I) Angulation 150 Abutment Increases Fracture Resistance Of The Overlaying CAM-milled Zirconia Single Crowns Than Straight Abutment. (II) All The Values Of Fracture Resistance Obtained In This Study Were Higher Than The Average Of Normal Occlusal Forces . (III) There Was Insignificant Difference Between The Posterior And Anterior Sites At Straight And Angulated.

Aya A. Hamzawy, Omneya M. Wahba And Iman S. ElShamy,

ABSTRACT
Background: Oral Cancer Represents 3% Of All Body Lesion With High Mortality Rate And Poor Prognosis. Lymph Node (LN) Metastasis Is One Of The Most Important Prognostic Factors Related To Survival Of Oral Squamous Cell Carcinoma (SCC). Overexpression Of Metastasis-associated Protein 1 (MTA1) Has Been Demonstrated In A Variety Of Human Cancers And Significantly Associated With The Tumor Size, Lymph Node Metastasis, Clinical Stage, Tumor Invasion, And Prognosis Of These Cancers; However, Its Role In Determining Lymph Node Metastases In Oral SCC Remains Unclear. OBJECTIVES: Detect And Compare The Expression Patterns Of MTA1 Immunohistochemically In Metastasizing And Non-metastasizing Oral SCC. MATERIALS AND METHODS: MTA1 Expression Was Detected Immunohistochemically In 40 Oral SCC Specimens And The Correlation With LN Metastasis Was Evaluated. RESULTS: Upregulation Of MTA1 Nuclear Expression Had A Significant Correlation With LN Metastasis But Not With The Histologic Grade Of The Tumor. CONCLUSIONS: The Present Study Suggests That Increased MTA1 Epithelial Cell-expression At The Invasive Front Reflects Its Potential Role During Invasion And Metastasis. Whereas, Nuclear Expression Of MTA1 Can Be Used A Predictor Of SCC Aggressiveness.

Fawzi HN, Amin SA And Bedier MM,

ABSTRACT

Objectives: The Aim Of This Prospective Randomized Clinical Trial Was To Compare The Degree Of Post-operative Pain And Analgesic Intake At 0, 4, 12, 24, 48, 72-h And 7 Days After The Use Of Two Different Irrigation Needles. Subjects And Methods: Thirty Eight Participants Diagnosed With Symptomatic Or Asymptomatic Irreversible Pulpitis In Mandibular Posterior Teeth Received Single-visit Root Canal Treatment And Were Divided Randomly Into Two Groups According To The Type Of Needle Used During Irrigation Either NaviTip 29-gauge, 27 Mm With End-Vented Needle (EVN) Or NaviTip 31-gauge, 27 Mm With Double Sideport Irrigator Tip (SVN). Post-operative Pain Was Measured Using Numeric Rating Scale (NRS) Pre-operatively, Immediate Post-operatively And At 4, 12, 24, 48, 72-h And 7 Days. Placebo And Analgesic Intake Was Recorded At The Different Time Intervals.

Results: There Was No Difference Between Both Groups In The NRS Scores At All Post-operative Time Points. A Significant Increase In Pain Level Was Recorded After 4-h Compared To The Immediate Post-operative In The EVN Group Followed By A Gradual Decrease In Pain Levels Until Pain Disappeared At 7 Days. No Difference In Medication (placebo Or Analgesic) Intake Post-operatively Was Recorded Between Both Groups.

Ragia Mounir , Omniya Abdel Aziz And Khaled Jamal ,

ABSTRACT
The Use Of Mineralized Plasmatic Matrix Derived From Autogenous Bone In Grafting Of The Residual Socket (socket Preservation) Aims To Preserve The Bone At The Same Level And To Regenerate New Bone With Better Quality As Compared To Socket Preservation Using Particulate Autogenous Bone Graft. The Goal Of The Present Study Evaluate And Assess The Effectiveness Of Mineralized Plasmatic Matrix (MPM) Versus Autogenous Bone Graft In Socket Preservation In Mandibular Anterior And Premolar Area. Methods:Ten Patients With Total 20 Extraction Sites In Lower Anterior And Premolar Area Who Fulfilled Specific Inclusion Criteria Were Assigned Into Two Groups Group A(Study Group), Group B (control Group). According To The Surgical Technique Used, In Study Group MPM Was Placed In Extraction Sockets Of Mandibular Anterior And Premolar Region, In Control Group Extraction Sockets Were Grafted With Autogenous Bone Graft, After 3 Months And Comparison And Implants Were Placed And Standardized X-ray Was Performed, Three Months Later Another X-ray Was Taken To Compare Crestal Bone Loss In Both Groups.

Results: Bone Loss Was Assessed In Both Group After 3 Months Following Implant Placement And Showed No Significant Difference.

Eman A. S. Khalaf, Laila E. Amin, Ayman M. Nagib And Fatma M.M. Ibrahim,

ABSTRACT
Objective: Chronic Renal Failure Can Elicit A Wide Spectrum Of Oral Manifestations In The Hard And Soft Tissues. Many Studies Have Demonstrated The Efficacy Of Casein Phosphopeptide Amorphous Calcium Phosphate With Fluoride Paste In Promoting Remineralization Of Enamel And Dentin In Vitro. Design: This Study Was Designed To Determine The Effect Of Renal Insufficiency On Patients? Teeth (enamel And Dentin) And Study Biological Effects Of Topical Application Of Fluoride On Extracted Teeth.

Materials and Methods: Twenty Sound Posterior Teeth Were Used, Divided Into 2 Groups, Group I (control Group) And Group II (fluoride Group). Each Group Was Subdivided Into 2 Subgroups; A (control) And B (uremic). All The Specimens Were Scanned By Using Scanning Electron Microscope And Elemental Analysis Of Enamel And Dentin Surfaces Was Tested Using Energy Dispersive Analytical X-ray.

Results: Enamel Of Uremic Teeth Showed Irregular Enamel Surface With Deep Depressions And Pitting. Also, Dentinal Tubules Showed Different Shaped Outlines And Diameter. The Application Of Fluoride Paste Was Significantly Increase In Calcium And Phosphorus Levels.

Conclusions: Chronic Renal Failure Leads To Alteration In The Structure Of Enamel And Dentin With Significant Increase In Mineral Content (Calcium & Phousphrous) When Compared With Healthy Teeth. The Topical Application Of Fluoride Was Effectively Enhanced The Remineralization And Counter Act Demineralization And Erosion.