Mansoura Journal of Dentistry最新文献

{"title":"Effect of veneering thickness and repeated firing on the flexural strength and translucency of lithium disilicate glass ceramic","authors":"A. Sheir, Walid Al-Zordk, Manal Abou Madina","doi":"10.21608/mjd.2021.199970","DOIUrl":"https://doi.org/10.21608/mjd.2021.199970","url":null,"abstract":"Objective: To evaluate effect of veneering thickness and repeated firing on the flexural strength and translucency of lithium disilicate glass ceramic. Materials and methods: Sixty-three-disc specimens were divided; each group have 21 discs specimens. First group was lithium disilicate core 1 mm with no veneering coverage, second group the lithium disilicate core was veneered by 0.5 mm nano flouroapatite glass ceramic. Third group was lithium disilicate core veneered by 1 mm nano flouroapatite glass ceramic. Each group was subjected to repeated firing cycles (3, 5, 7). Seven-disc specimens for each firing cycle were used to measure translucency then flexural strength. The degree of color difference between the compared colors was expressed in ∆E units. The total color difference, according to L*, H*, C* coordinates, was calculated. Then change in TP (∆TP) which is the difference between first and second sample regarding thickness and firing cycles was measured to determine the acceptability threshold. Then fracture load was applied to all specimens fixed on 3 balls fixture under static compressive loading using universal testing machine to determine the flexural strength. The results were tabulated and statistical analysis was performedusing repeated way ANOVA method. Results: Regarding value, chroma and hue, in 3 firing cycles value means revealed a significant difference in the comparison between 1 mm, 1.5 mm (P=0.001) thickness and between 1 mm, 2 mm (P=0.001) but non-significant difference was shown between 1.5 mm and 2 mm (P=0.325). While chroma and hue showed significant difference in comparison between 1 mm, 1.5 mm and 2 mm (P=0.001). However, in 5 firing cycles, value showed significant difference between 1 mm, 1.5 mm and 1 mm, 2 mm (P=0.001) and also between 1.5 mm, 2 mm (P=0.016), and chroma also showed significant difference between 1 mm, 1.5 mm, 2 mm (P=0.001), and hue showed significant difference between 1 mm, 1.5 mm (P=0.027), and also between 1 mm, 2 mm and 1.5 mm, 2 mm. However, in 7 firing cycles, value showed significant difference in comparison between 1 mm, 1.5 mm (P=0.001) and 1 mm, 2 mm (P=0.001) but non-significant difference was revealed between 1.5 mm, 2 mm (P=0.053). While chroma showed significant difference between 1 mm, 1.5 mm and 2 mm (P=0.001), while hue showed significant difference in comparison between 1 mm, 1.5 mm (P=0.001) but non-significant difference was found between 1 mm, 2 mm (P=0.11) and 1.5 mm, 2 mm (P=0.148). Translucency parameters revealed a significant difference (P=0.001) between different firing cycles with different thickness. Flexural strength showed no significant decrease with increasing firing cycles from 3 to 5 firing cycles in the same 1 mm thickness (P=0.153) and showed significant decrease on increasing firing cycles from 3 to 7 cycles (P=0.001) and 5 to 7 cycles (P=0.005). While in 1.5 mm thickness showed significant decrease in flexural strength on increasing firing cycles from 3 to 5 ","PeriodicalId":308616,"journal":{"name":"Mansoura Journal of Dentistry","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132203685","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of different Surface Treatments of Orthodontic Mini-Implants on their Primary Stability; An in-vitro study","authors":"Safwat Ahmed, Montasser Mona A","doi":"10.21608/mjd.2021.222418","DOIUrl":"https://doi.org/10.21608/mjd.2021.222418","url":null,"abstract":"MIs were invented in orthodontic to achieve the absolute skeletal orthodontic anchorage (1) . OMIs overall stability in the maxillo-facial bones has always being a key factor for their success and come from the sum of achievement of each of the primary stability through the mechanical interlocking of OMIs in to the bone immediately after their insertion and the secondary stability, which is achieved later after a healing period by the osseointegration process (2-5) . A set of overlapping factors have a large impact on OMIs stability, some of which return to the clinical steps, others return on OMIs descriptions and the patient himself will be a contributing factor in achieving that success (2) . OMIs Surface modification have to be more recommended for improving their stability and the compensation for lack of other factors through increasing bone to mini-implants contact (BIC) and removal torque values (RTv). OMIs surface treatments required several techniques included sandblasting, acid-etching, anodization and laser surface treatment techniques (6-10) . This study o Ahmed Safwat Mohamed , Noha El-Wassefy , Marwa Ali Tawfik , Mona Abdelaziz Montasser (4) (1) Dentist, Ministry of Health, Damietta, Egypt. (2) Associate Professor, Department of Dental Biomaterials, Faculty of Dentistry, Mansoura University, Egypt. (3) Lecturer, Department of Orthodontics, Faculty of Dentistry, Mansoura University, Egypt. (4) Professor, Department of Orthodontics, Faculty of Dentistry, Mansoura University, Egypt.","PeriodicalId":308616,"journal":{"name":"Mansoura Journal of Dentistry","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125211764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of mean vascular density (MVD) and cells adhesion in oral squamous cell carcinoma. An immunohistochemical study.","authors":"","doi":"10.21608/mjd.2021.199969","DOIUrl":"https://doi.org/10.21608/mjd.2021.199969","url":null,"abstract":"","PeriodicalId":308616,"journal":{"name":"Mansoura Journal of Dentistry","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115500645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Maxillary Buccal Alveolar Bone Assessment Following Orthodontic Alignment Without Extractions (Cone beam study)","authors":"Abdelshafy Ali Megahed Abdelshafy, Ibrahim Saad Abd El-Ghafar, Hussein Shokry Hassan Ahmed, M. Salem","doi":"10.21608/mjd.2021.199966","DOIUrl":"https://doi.org/10.21608/mjd.2021.199966","url":null,"abstract":": Objective: Assessment of maxillary buccal alveolar bone following orthodontic alignment without extractions.(Cone beam study). Materials and Methods: Twenty adolescents with crowded permanent dentitions were treated without extractions with EASY SMILE (USA) Orthodontic self-ligating bracket brackets & conventional brackets. Cone beam computed tomographic scans were taken before treatment (T0) and after alignment (T1). Alveolar bone thickness (BT) was evaluated at the maxillary central incisor (I), second premolar (2PM), and first molar mesiobuccal (mb1M) and distobuccal (db1M) roots. Correlations between alveolar width changes and initial arch width, initial crowding, amount of expansion, amount of tipping, and amount of molar rotation were calculated were calculated. All data collected will be tabulated and statistically analyzed. Results: BT decreased and BH increased significantly for the incisors and mesiobuccal(mb1M) root of the first molars. Also, arch dimensions generally increased together with tipping. Bone loss was correlated with crowding and amount of expansion in the premolar region. Conclusion: Nonextraction alignment resulted in arch expansion associated with tipping of teeth for both self-ligating brackets & conventional brackets. Alignment with expansion led to horizontal and vertical bone loss at the incisors and mesiobuccal root of the first molars. Thinner BTs and more severe crowding before treatment led to increase the risk for buccal bone loss.","PeriodicalId":308616,"journal":{"name":"Mansoura Journal of Dentistry","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126236455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of Mechanical, Optical and Surface Changes of Pretreated Enamel Surface Bonded to Orthodontic Bracket Using Different Remineralizing Agents","authors":"Nesma M. Khater, Reham M Abdallah, M. Osman","doi":"10.21608/mjd.2021.199974","DOIUrl":"https://doi.org/10.21608/mjd.2021.199974","url":null,"abstract":"Objective: This study aimed to evaluate the effect of CPP-ACP, CPP-ACPF and nano-hydroxyapatite on enamel remineralization during fixed Orthodontic treatment. The treated specimens with different remineralizing agents were compared with their untreated and demineralized ones regarding surface roughness, surface microhardness, and color measurement. Materials and methods: A total number of 120 specimens from extracted orthodontic patient teeth was collected and divided into 4 equal groups (10 specimens each) according to the enamel surface treatment applied immediately after PH cycling; group A received no surface treatment and served as a control group. In group B, the enamel surface was treated by CPP-ACP, while group C enamel surface was treated by CPP-ACFP, and group D was treated by Desensibilize NanoP. The surface roughness was obtained using surface Profilometer and Vickers microhardness was measured using Digital Display Vickers Microhardness Tester. Evaluation for each specimen was performed before, after pH cycling and after using different remineralizing agents. The color change was analyzed for each specimen in different groups under the Spectrophotometer. The change in color from control specimens compared to the color of the demineralized specimens (ΔE1), the difference in color between control specimens and after remineralization (ΔE2) and the change in color between demineralized and remineralized specimens (ΔE3) were calculated. The results were then statistically analyzed and compared using ANOVA and LSD test at level of significance 0.05. Results: The use of CPP-ACP, CCP-ACFP and NanoP significantly improved surface roughness, surface microhardness especially with NanoP with non-significant difference between the three remineralizing materials. NanoP exhibited the lowest change in color compared with CPP-ACFP and CPP-ACP paste. Conclusion: The use of CPP-ACP, CPP-ACFP and NanoP could be used as preventive materials during orthodontic treatment and be effective in repairing the demineralized enamel restoring its surface smoothness, hardness, and color.","PeriodicalId":308616,"journal":{"name":"Mansoura Journal of Dentistry","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128451507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chemical Stability of the Biomineralized Initial Enamel Caries","authors":"R. Marwa, E. Wedad, G. Thuraia","doi":"10.21608/mjd.2021.199973","DOIUrl":"https://doi.org/10.21608/mjd.2021.199973","url":null,"abstract":"","PeriodicalId":308616,"journal":{"name":"Mansoura Journal of Dentistry","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130000567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of Knowledge, Attitude and Practice of Infection Control principles Among A Sample of Egyptian Dental Students.","authors":"GhadaEzzat Al-Hindawyt, N. Attia, S. Hegazy","doi":"10.21608/mjd.2021.199843","DOIUrl":"https://doi.org/10.21608/mjd.2021.199843","url":null,"abstract":"Background: Dental students are at great risk of cross-infection and accidental sharp injuries. Sharp injuries are the main risk for viral infections' transmission such as HBV, HCV, and HIV. The hazard of sharp injuries is generally reduced by following the proper safety measures in clinical training, and student vaccination particularly HBV vaccine. Aim: this study was conducted to evaluate the knowledge about infectious diseases transmission, HBV vaccination status, attitude, and practice of treating patients with infectious diseases,history of occupational injuries, and post exposure management among 4 th and 5 grades dental students in the Faculty of dentistry in both Mansoura and Delta universities. Method: Atotal of 798 dental students in 4th and 5th grades in both universities were chosen randomly and participated in this cross sectional study. A self-administered questionnaire was designed to evaluate the knowledge, attitude, and practice of dental students toward infectious diseases that transmitted during dental procedures, post exposure management and their vaccination status. After data collection, they were analyzed using (SPSS) program. Results:Mansoura University students had significantly higher correct knowledge about salivary diseases transmission. As well as, significantly higher percentage of Mansoura dental students (90.1%)were vaccinated against HBV Compared to (82.7%) of Delta dental students.On the other hand, both Mansoura and Delta students had correct knowledge about taking medical history and post exposure management without significant difference between them. Mansoura University students had significantly higher attitude towards treating patientswith infectious diseases (89.5%) in comparison to Delta university students (85.4%). But, they had lower practice. Conclusion: Dental students in both Mansoura and Delta Universities had lower level of knowledge about salivary diseases transmission. But, the majority of them were vaccinated against HBV. In contrast, they had high knowledge and attitude toward treating patients with infectious diseases but moderate practice.","PeriodicalId":308616,"journal":{"name":"Mansoura Journal of Dentistry","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128266914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In-Office Bleaching Techniques: Laboratory Investigation of the Effect on Color Change and EnamelMicromorphology","authors":"Muazaz Fawzi Hamed, Ashraf Ibrahim, H. A. Mohammed","doi":"10.21608/mjd.2021.199844","DOIUrl":"https://doi.org/10.21608/mjd.2021.199844","url":null,"abstract":"Objectives: This study was conducted to evaluate and compare the effect of different in-office bleaching techniques on color change and enamel surface micromorphology. Materials and Methods:Three different bleaching agents(one light-activated and two chemical-activated) were selected for this study. Sixty sound human permanent maxillary central incisors were selected andfixedin cylinder plastic mold (2 cm width and 1cm height) fabricated with using selfpolymerized acrylic resin.Teeth were assigned into two groups according to the test conductedon, color test group (n=30), and themicro-morphology test group(n=30). Each group was further classified into three subgroups(n=10) according to the bleaching material used. The subgroups of each bleaching material were tested for enamel color change assessment usingaspectrophotometer and for surface micromorphology assessment by a non-contact optical profilometer before and after bleaching application. Data for each test wastabulated and statistically analyzed. Results: Regarding color change analysis,all tested bleaching materials were effective on tooth color whitening,there was statistical significant differenceinthe mean value of all tested groups (P=0.011). With higher mean values recorded for Zoom group followed by Dash and Boost groups. Regarding the results of surface micromorphology, all the tested bleaching materials showed no statistical significant difference in enamel surface roughness after bleaching(P=0.591). Conclusions: All thetestedin-officebleaching systemswere effectivelywhiten teeth, with light-activated systemexhibited higher whitening potential than chemical-activatedbleaching systems, with insignificant changein enamel micromorphology. In-Office Bleaching Techniques: Laboratory Investigation of the Effect on Color Change and EnamelMicromorphology Mansoura Journal of Dentistry 2021;8(29):17-21. 18 Muazaz Fawzi Hamed have found alterations in surface morphology, calcium loss and changes in chemical composition of enamel. 18-20 Thus, this study was performed to evaluate the effect of three different in-office bleaching systems on color change and enamel micromorphology. Aim of Study This study was intended to evaluate and compare the effect of different in-office bleaching techniques on the color change and enamel surface micromorphology. Null hypothesis This study was conducted to testthe null hypothesis that, the tested in-office bleaching techniquesneither differ in its bleaching efficacy nor in changingthe enamel micromorphology. I. Materials and Methods Three different types of commercially available in-office teeth bleaching materials which are; one light-activated bleaching agent (Zoom) and two chemical-activated agents (Opalescence X-tra Boost, Dash)were used in this study. A total number of 60 human permanent incisors extracted due to periodontal diseases were obtained from Outpatient Clinic, Oral Surgery Department, Faculty of Dentistry at Mansoura University. All collected t","PeriodicalId":308616,"journal":{"name":"Mansoura Journal of Dentistry","volume":"318 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115447761","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Etching Method and Time on Surface Roughness and Shear Bond Strength of a Novel Universal Adhesive to Ground Enamel","authors":"Amal Mansoor Ali AL-Qadhi, R. I. El-Toukhy, S. Mahmoud","doi":"10.21608/mjd.2021.199847","DOIUrl":"https://doi.org/10.21608/mjd.2021.199847","url":null,"abstract":"PLA is considered one of complex acids that containspolyacrylic, polyitaconic, and polymaleic acids, it is used in etching for cavity cleaning and conditioning in restorations with glass ionomer cement.PLA forms ionic bond between carboxyl groups and calcium of HAp. 4 Another etching technique is the recently developed PPM. 12 The composition of this acid characterizes by containing a functional monomer 10-MDP. It is a versatile monomer composes oflong carbon chain with two ends of hydroxyl groups. Thus, chemical reaction with dental substrates, resulting in higher bonding strength rather than mechanical adhesion only. 15","PeriodicalId":308616,"journal":{"name":"Mansoura Journal of Dentistry","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132541050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tissue Engineering and Regenerative Endodontics","authors":"","doi":"10.21608/mjd.2021.199845","DOIUrl":"https://doi.org/10.21608/mjd.2021.199845","url":null,"abstract":"","PeriodicalId":308616,"journal":{"name":"Mansoura Journal of Dentistry","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125349589","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}