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  1. Article ; Online: Effect of coping materials zirconia or polyetheretherketone with different techniques of fabrication on vertical marginal gap and fracture resistance of posterior crowns with composite veneering.

    Emam, Marwa / Metwally, Mohamed F

    BMC oral health

    2023  Volume 23, Issue 1, Page(s) 546

    Abstract: Background: Insufficient research has been conducted in the literature assessing the performance of zirconia and polyetheretherketone (PEEK) crowns in relation to the essential requirements of successful restorations, such as fracture resistance or ... ...

    Abstract Background: Insufficient research has been conducted in the literature assessing the performance of zirconia and polyetheretherketone (PEEK) crowns in relation to the essential requirements of successful restorations, such as fracture resistance or margin adaptation. The purpose of this study was to evaluate the effect of the coping materials zirconia or PEEK with different fabrication techniques on the vertical marginal gap and fracture resistance of posterior crowns with composite veneering.
    Methods: Ceramic copings (n = 18) restoring mandibular first molar were fabricated from zirconia (Zircon.x, Presidentdental, Germany), milled PEEK (PEEK CAD) (breCAM.BioHPP, Bredent, Germany) and pressed PEEK (PEEK Press) (BioHPP Granules, Bredent, Germany) six specimens each (n = 6). The copings were veneered with high impact polymer composite (HIPC) material (breCAM.HIPC, Bredent, Germany). The vertical marginal gap was captured under a magnification of 40X. Five equidistant marks on each surface of the die distinguished the points of measurement for a total of 20 readings per sample. The analysis was completed using an image analysis system (ImageJ 1.53t, National Institute of Health, USA). The specimens were loaded to failure at a crosshead speed of 1 mm/min and the load at failure was recorded to measure the fracture resistance.
    Results: The marginal gap was analyzed using one-way ANOVA followed by Tukey's post hoc test. Fracture resistance was analyzed using Welch one-way ANOVA followed by the Games-Howell post hoc test. Marginal gap values showed a significant difference between the tested groups, with zirconia having significantly lower gap values (48.67 ± 11.98 µm) than both the PEEK CAD (108.00 ± 20.08 µm) and Press groups (108.00 ± 25.10 µm) (p < 0.001). However, the results of fracture resistance showed no significant difference (p = 0.06) with 1687.47 ± 253.29 N, 2156.82 ± 407.64 N, 2436.72 ± 725.93 N for zirconia, PEEK CAD, and Press, respectively. The significance level was p < 0.05.
    Conclusions: Zirconia framework crowns have a smaller vertical marginal gap than milled and pressed PEEK crowns. Crowns fabricated from zirconia, PEEK CAD, or PEEK Press frameworks and veneered with composite resin have comparable fracture resistance lower than the maximum biting force in the posterior region.
    Clinical relevance: Posterior crowns with zirconia frameworks are preferred over milled and pressed PEEK frameworks regarding margin adaptation, although all can safely survive the maximum occlusal forces without fracture.
    MeSH term(s) Humans ; Dental Porcelain ; Crowns ; Polyethylene Glycols ; Ketones ; Adaptation, Psychological ; Computer-Aided Design ; Materials Testing ; Dental Prosthesis Design
    Chemical Substances polyetheretherketone (31694-16-3) ; Dental Porcelain (12001-21-7) ; zirconium oxide (S38N85C5G0) ; Polyethylene Glycols (3WJQ0SDW1A) ; Ketones
    Language English
    Publishing date 2023-08-09
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2091511-1
    ISSN 1472-6831 ; 1472-6831
    ISSN (online) 1472-6831
    ISSN 1472-6831
    DOI 10.1186/s12903-023-03247-w
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Stress distribution and fracture resistance of green reprocessed polyetheretherketone (PEEK) single implant crown restorations compared to unreprocessed PEEK and Zirconia: an in-vitro study.

    Emam, Marwa / Arafa, Ahmed Mohamed

    BMC oral health

    2023  Volume 23, Issue 1, Page(s) 275

    Abstract: Background: It is unclear which crown materials are optimum to disperse the generated stresses around dental implants. The objective of this study is to assess stress distribution and fracture resistance of green reprocessed Polyetheretherketone (PEEK) ... ...

    Abstract Background: It is unclear which crown materials are optimum to disperse the generated stresses around dental implants. The objective of this study is to assess stress distribution and fracture resistance of green reprocessed Polyetheretherketone (PEEK) in comparison to un-reprocessed PEEK and zirconia single implant crown restorations.
    Methods: Twenty crowns (n = 20) were obtained, five from zirconia and fifteen from pressed PEEK that were subdivided into 3 groups of five specimens each (n = 5) according to weight% of reprocessed material used. A 100% new PEEK was used for the first group, 50% new and 50% reprocessed PEEK were used for the second group, and a 100% reprocessed PEEK was used for the third group. Epoxy resin model with dental implant in the second mandibular premolar was constructed with strain gauges located mesially and distally to the implant to record strain while a load of 100 N was applied with 0.5 mm/min then specimens of all groups were vertically loaded till failure in a universal testing machine at cross head speed 1 mm/min. Data was statistically analyzed by using One-way Analysis of Variance (ANOVA) followed by Post-hoc test when ANOVA test is significant.
    Results: No significant difference between strain values of tested groups (p = 0.174) was noticed. However, a significant difference between fracture resistance values was noticed where the zirconia group recorded a significantly higher value (p < 0.001).
    Conclusions: Implant restorative materials with different moduli of elasticity have similar effects regarding stresses distributed through dental implant and their surrounding bone. Reprocessed PEEK implant restorations transmit similar stresses to dental implant and surrounding bone as non-reprocessed PEEK and zirconia restorations. Zirconia failed at higher load values than all tested PEEK restorations but all can be safely used in the posterior area as crown restorations for single implants.
    Clinical relevance: Applying "green dentistry" principles may extend to include reprocessing of pressed PEEK restorative materials without affecting the material's shock absorption properties.
    MeSH term(s) Humans ; Dental Implants ; Dental Stress Analysis ; Crowns ; Polyethylene Glycols ; Ketones ; Dental Materials ; Materials Testing ; Dental Restoration Failure ; Titanium
    Chemical Substances polyetheretherketone (31694-16-3) ; zirconium oxide (S38N85C5G0) ; Dental Implants ; Polyethylene Glycols (3WJQ0SDW1A) ; Ketones ; Dental Materials ; Titanium (D1JT611TNE)
    Language English
    Publishing date 2023-05-11
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2091511-1
    ISSN 1472-6831 ; 1472-6831
    ISSN (online) 1472-6831
    ISSN 1472-6831
    DOI 10.1186/s12903-023-02943-x
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: Hip Fracture Care in the Emergency Department: It's Time to Push Fast-Track.

    Daunt, R / Al Emam, M / Willoughby, M / Brewer, L

    Irish medical journal

    2022  Volume 115, Issue 1, Page(s) 532

    MeSH term(s) Emergency Service, Hospital ; Hip Fractures/surgery ; Humans
    Language English
    Publishing date 2022-01-20
    Publishing country Ireland
    Document type Letter
    ZDB-ID 193134-9
    ISSN 0332-3102 ; 0021-129X
    ISSN 0332-3102 ; 0021-129X
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: Pervious Concrete Made with Recycled Coarse Aggregate and Reinforced with Date Palm Leaves Fibers.

    Tamimi, Adil / Tabsh, Sami W / El-Emam, Magdi

    Materials (Basel, Switzerland)

    2023  Volume 16, Issue 23

    Abstract: This study considers 12 pervious concrete mixes incorporating 100% recycled coarse aggregate from old concrete demolition waste and containing various amounts of natural fine aggregate and date palm leaves fibers. First, the properties of the recycled ... ...

    Abstract This study considers 12 pervious concrete mixes incorporating 100% recycled coarse aggregate from old concrete demolition waste and containing various amounts of natural fine aggregate and date palm leaves fibers. First, the properties of the recycled aggregate in terms of their particle size distribution, abrasion resistance, crushing values, specific gravity and water absorption are obtained. Next, the pervious concrete density, compressive strength, tensile strength, permeability and porosity are determined by experimental testing following the relevant standards. The results are analyzed and compared to determine the influence of using recycled coarse aggregate in the mixtures and the impact of the amount of natural sand and volume fraction of the fibers on the mechanical properties, permeability and porosity of the concrete. Findings of the study showed that the use of recycled coarse aggregate in pervious concrete without fine aggregate reduced the compressive strength by 36% and tensile strength by 57%. Replacing 11.7% of the recycled coarse aggregate with natural sand and adding date palm leaves fibers in an amount equivalent to 0.64% volumetric content to such concrete helped increase the compressive strength by 16.2% and tensile strength by 3.2% above the corresponding strengths of the control mix. There is a clear relationship between permeability and porosity due to their correlation with the density of pervious concrete, and the effect of porosity on tensile strength is more influential than it is on the compressive strength. An equation that can predict the tensile strength of pervious concrete from the compressive strength is proposed, as a function of the natural fine aggregate fraction of the coarse aggregate and volumetric content of natural fibers. Results of the research confirm the feasibility of using recycled aggregate in pervious concrete mixes and the positive impact of natural fibers on the mechanical properties.
    Language English
    Publishing date 2023-12-04
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2487261-1
    ISSN 1996-1944
    ISSN 1996-1944
    DOI 10.3390/ma16237496
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Effect of different intraoral scanners and post-space depths on the trueness of digital impressions.

    Emam, Marwa / Ghanem, Lomaya / Abdel Sadek, Hoda M

    Dental and medical problems

    2023  

    Abstract: Background: The trueness of intraoral scanners (IOSs) has been evaluated in many clinical situations. However, the tests of their performance when scanning post-space preparations are still lacking.: Objectives: The aim of the present study was to ... ...

    Abstract Background: The trueness of intraoral scanners (IOSs) has been evaluated in many clinical situations. However, the tests of their performance when scanning post-space preparations are still lacking.
    Objectives: The aim of the present study was to compare the trueness of the digital impressions of post spaces with different depths, captured by means of different IOSs.
    Material and methods: Digital impressions of teeth (N = 16) with post spaces of depths of 8 mm and 10 mm were captured. Three IOSs were used, including Primescan AC, Medit i500 and CS 3600. The STL files were compared to the files obtained from the traditional impression scanning performed with an InEos X5 desktop scanner. Then, reverse engineering software measured the trueness values, which were analyzed using the two-way analysis of variance (ANOVA), followed by Tukey's post-hoc test. The significance level was set at p < 0.05.
    Results: Significant differences were found between the scanners in terms of root mean square (RMS) values (p < 0.001). The highest RMS value was found for CS 3600 (0.30 ±0.11 mm), followed by Primescan AC (0.26 ±0.09 mm), while the lowest value was found for Medit i500 (0.18 ±0.05 mm). The 8-millimeter-deep post spaces had a significantly higher RMS value than the 10-millimeter-deep ones (0.28 ±0.10 mm and 0.21 ±0.09 mm, respectively) (p = 0.009).
    Conclusions: The Medit i500 scanner showed the highest post-space digital impression trueness as compared to Primescan AC and CS 3600. In the digital impressions captured with CS 3600, the 10 mm postspace depth had higher trueness than the 8 mm depth. Moreover, CS 3600 was less able to capture the full length of both the 8 mm and 10 mm post-space depths than Primescan AC and Medit i500.
    Language English
    Publishing date 2023-04-18
    Publishing country Poland
    Document type Journal Article
    ZDB-ID 2592057-1
    ISSN 2300-9020 ; 2300-9020
    ISSN (online) 2300-9020
    ISSN 2300-9020
    DOI 10.17219/dmp/162573
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: An investigation of the effects of meteorological factors on the incidence of tuberculosis.

    Chang, Minli / Emam, Mawlanjan / Chen, Xiaodie / Lu, Dongmei / Zhang, Liping / Zheng, Yanling

    Scientific reports

    2024  Volume 14, Issue 1, Page(s) 2088

    Abstract: To explore the influence of meteorological factors on the incidence of tuberculosis (TB) in Yingjisha County, Kashgar Region, Xinjiang, and to provide a scientific basis for the prevention and control of TB. The Spearman correlation analysis and ... ...

    Abstract To explore the influence of meteorological factors on the incidence of tuberculosis (TB) in Yingjisha County, Kashgar Region, Xinjiang, and to provide a scientific basis for the prevention and control of TB. The Spearman correlation analysis and distribution lag nonlinear model analysis were conducted on the number of daily reported cases of TB from 2016 to 2023 to study the association effect of various meteorological factors and the daily incidence number of TB in Yingjisha County. A total of 13,288 TB cases were reported from January 2016 to June 2023, and June to October is the peak period of annual TB incidence. Spearman correlation analysis revealed that average daily temperature (AT) and average daily wind speed (WS) were positively correlated with TB incidence (r
    MeSH term(s) Humans ; Female ; Incidence ; Meteorological Concepts ; Tuberculosis/epidemiology ; Weather ; Latent Tuberculosis
    Language English
    Publishing date 2024-01-24
    Publishing country England
    Document type Journal Article
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-024-52278-y
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: Simultaneous Ipsilateral Anterior Cruciate Ligament and Proximal Hamstring Tendon Ruptures: A Case Report.

    Mikula, Jacob D / Kreulen, R Timothy / Johnson, Ken / Emam, Mohammed / Wilckens, John H

    Journal of orthopaedic case reports

    2024  Volume 14, Issue 4, Page(s) 125–129

    Abstract: Introduction: Simultaneous anterior cruciate ligament (ACL) and ipsilateral hamstring ruptures have never been reported in the literature. The purpose of this article is to describe a treatment approach for such a case. The principles in this case can ... ...

    Abstract Introduction: Simultaneous anterior cruciate ligament (ACL) and ipsilateral hamstring ruptures have never been reported in the literature. The purpose of this article is to describe a treatment approach for such a case. The principles in this case can help guide treatment for any patient with concomitant ACL and hamstring pathology.
    Case report: We describe the case of a 53-year-old male who presented with left ipsilateral simultaneous complete proximal hamstring tendon (HT) and ACL tears after an acute tennis injury. He was successfully treated with a staged procedure, first with a proximal HT repair and later with a delayed ACL reconstruction using a bone-patellar tendon-bone autograft.
    Conclusion: Ipsilateral simultaneous complete proximal HT and ACL tears can be successfully treated with acute proximal HT repair and delayed ACL reconstruction after rehabilitation from the HT repair. The synergistic relationship between the ACL and hamstring muscles in preventing anterior translation of the tibia necessitates staged reconstruction in the setting of a simultaneous injury.
    Language English
    Publishing date 2024-04-26
    Publishing country India
    Document type Case Reports
    ZDB-ID 2658169-3
    ISSN 2250-0685
    ISSN 2250-0685
    DOI 10.13107/jocr.2024.v14.i04.4384
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: MHD dissipative Powell-Eyring fluid flow due to a stretching sheet with convective boundary conditions and slip velocity.

    Abbas, W / Megahed, Ahmed M / Emam, M S / Sadek, Hassan M H

    Scientific reports

    2023  Volume 13, Issue 1, Page(s) 15674

    Abstract: The novelty and motivation of this research can be emphasized by examining how the heat transfer mechanism of a non-Newtonian Powell-Eyring fluid, which flows because of a stretched sheet, is affected by factors like viscous dissipation, the slip ... ...

    Abstract The novelty and motivation of this research can be emphasized by examining how the heat transfer mechanism of a non-Newtonian Powell-Eyring fluid, which flows because of a stretched sheet, is affected by factors like viscous dissipation, the slip velocity phenomenon, and Joule heating. In addition, the investigation delves into the heat transfer behavior of the fluid flow when it comes into contact with a convectively heated stretched surface that is influenced by varying fluid properties. This analysis also takes into account the influence of changing fluid characteristics and the presence of magnetic field. The numerical solutions of modelled equations that governing the problem are detected using the shooting technique. Also, in order to confirm the validity of the present investigation, a proper comparison with certain published works as a particular case of the present model is presented, and a perfect agreement is noted. With the use of diagrams and tables, the flow problem's effective parameters are thoroughly discussed. Likewise, through a tabular representation, the values of the local Nusselt number and the skin-friction coefficient are computed and analyzed. Many significant conclusions can be drawn from numerical results. Most importantly, the local Nusselt number rises monotonically with both the surface convection parameter and the slip velocity parameter, but the local skin-friction coefficient has the opposite trend. The results indicate that the nanofluid temperature is enhanced by factors such as the surface convection parameter, magnetic field, and viscous dissipation. On the other hand, the slip velocity phenomenon leads to the opposite effect.
    Language English
    Publishing date 2023-09-21
    Publishing country England
    Document type Journal Article
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-023-42609-w
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Conference proceedings: Outcomes of Thermal Ablation Combined with u/s-Guided Foam Sclerotherapy in Treatment of Superficial Venous Reflux in Patients with Postphlebitic Venous Leg Ulcer

    Galy, Mohamed El / Rady, Mohamed / Emam, Mohamed / Ismail, Mohamed

    The Arab Journal of Interventional Radiology

    2024  Volume 08, Issue S 01

    Event/congress PAIRS 2024 Annual Congress, World Trade Center, Dubai, UAE, 2024-02-10
    Language English
    Publishing date 2024-02-01
    Publisher Georg Thieme Verlag KG
    Publishing place Stuttgart ; New York
    Document type Article ; Conference proceedings
    ISSN 2542-7083 ; 2542-7075
    ISSN (online) 2542-7083
    ISSN 2542-7075
    DOI 10.1055/s-0044-1785905
    Database Thieme publisher's database

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  10. Article ; Online: Fistula of acromioclavicular cyst treated with a staged reverse total shoulder arthroplasty: a case report.

    Emam, Mohammed / Singhani, Neil / Persaud, Christine / Aibinder, William

    BMC musculoskeletal disorders

    2022  Volume 23, Issue 1, Page(s) 1005

    Abstract: Background: Acromioclavicular (AC) joint cysts are relatively rare. There are two distinct etiologies of AC cysts. Type 1 is isolated to the AC joint, while type 2, is related to a tear or rupture of the rotator cuff (RC). The disease is usually a rare ... ...

    Abstract Background: Acromioclavicular (AC) joint cysts are relatively rare. There are two distinct etiologies of AC cysts. Type 1 is isolated to the AC joint, while type 2, is related to a tear or rupture of the rotator cuff (RC). The disease is usually a rare result of advanced AC joint arthritis or RC-tear arthropathy. Patients may present with signs and symptoms of RC impingement and tear. Conservative management may be used initially in asymptomatic individuals who are also not concerned with cosmesis. Aspiration and steroid injection of the cyst has been reported as one method of non-surgical management of these lesions, however, there is a high rate of recurrence.
    Case presentation: We report a case of A 72-year-old right-handed female with past medical history of type two diabetes mellitus, chronic smoking, and a prior right RC repair with distal clavicle resection who presented with an AC joint cyst complicated by a draining fistula as a result of cyst aspiration and steroid injection. Due to the persistent drainage of the cyst and concern for infection, the patient was treated with a staged reverse shoulder arthroplasty given the setting of an irreparable rotator cuff tear and end-stage cuff-tear arthropathy.
    Conclusion: This case demonstrates an important complication of persistent draining fistula resulting from AC joint cyst aspiration and steroid injection in the setting of advanced RC-tear arthropathy. In immunocompromised patients, staged reverse shoulder arthroplasty should be considered for treatment of these draining fistulas especially when the concern for periprosthetic infection is high.
    MeSH term(s) Humans ; Female ; Aged ; Arthroplasty, Replacement, Shoulder ; Rotator Cuff Tear Arthropathy ; Fistula ; Cysts/complications ; Cysts/diagnostic imaging ; Inflammation ; Steroids
    Chemical Substances Steroids
    Language English
    Publishing date 2022-11-22
    Publishing country England
    Document type Case Reports ; Journal Article
    ZDB-ID 2041355-5
    ISSN 1471-2474 ; 1471-2474
    ISSN (online) 1471-2474
    ISSN 1471-2474
    DOI 10.1186/s12891-022-05976-5
    Database MEDical Literature Analysis and Retrieval System OnLINE

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