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Ibrahim Nergiz - One of the best experts on this subject based on the ideXlab platform.
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the fit of tapered posts in root canals luted with Zinc Phosphate Cement a histological study
Dental Materials, 2005Co-Authors: Petra Schmage, Mutlu Özcan, Candice Mcmullanvogel, Ibrahim NergizAbstract:Objectives. Stress transmission to the root through passive fitting dental posts is partly influenced by the thickness of the Cement layer between the post and the prepared root canal surface as well as the fit of the post in the root canal. The objective of this study was to compare the Cement gap between the post surfaces and the root canals using five prefabricated, tapered, unthreaded titanium posts of different manufacturers, without and with Cement. Methods. Following the endodontic treatment with hand instruments of 100 intact anterior teeth, post spaces were prepared using opening drills of the corresponding size of post. Fifty posts were Cemented with Zinc Phosphate Cement into the roots for each system while another 50 posts were inserted into the canal without using the Cement. After histological sectioning, the Cement gap was measured at six sites for three times at the coronal, middle and apical regions between the root canal wall and the post surface under a light microscope before and after Cementation. Results. Before Cementation, the highest overall Cement gap was observed with the Dr Mooser post system (R) (46 mu m) and the lowest with the Velva post system (R) and Cylindro-Conical system (R) (30 mu m). Significantly less (P 0.001) compared with Velva-Post (R) (38, 20 mu m) at the coronal and middle part, respectively (Mann-Whitney U-test, Boneferroni correction). Significant differences (P <0.001) were observed between the Cement gap at the coronal and apical part for the Cylindro-Conical system (R) (79, 46 mu m), Dr Mooser post system (R) (45, 56 mu m) and MP Pirec post system (R) (25, 52 mu m). After Cementation, the highest Cement gap at the coronal part was obtained with the Cylindro-Conical system (R) (79 +/- 21 mu m) and the lowest with the MP Pirec post system (R) (25 +/- 9 mu m). However, at the apical end, the MP Pirec post system (R) (52 +/- 89 gm) and Dr Mooser post system (R) (56 +/- 16 gm) revealed the highest gap. Significance. Form-congruence between the preparation drill and the post systems exhibited differences. The most consistent Cement gap either at the coronal, middle or apical parts of the root canals was obtained with the Erlangen post system (R). (c) 2005 Academy of Dental Materials. Published by Elsevier Ltd. All. rights reserved.
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The fit of tapered posts in root canals luted with Zinc Phosphate Cement: A histological study
Dental materials : official publication of the Academy of Dental Materials, 2005Co-Authors: Petra Schmage, Mutlu Özcan, Candice G. Mcmullan-vogel, Ibrahim NergizAbstract:Objectives. Stress transmission to the root through passive fitting dental posts is partly influenced by the thickness of the Cement layer between the post and the prepared root canal surface as well as the fit of the post in the root canal. The objective of this study was to compare the Cement gap between the post surfaces and the root canals using five prefabricated, tapered, unthreaded titanium posts of different manufacturers, without and with Cement. Methods. Following the endodontic treatment with hand instruments of 100 intact anterior teeth, post spaces were prepared using opening drills of the corresponding size of post. Fifty posts were Cemented with Zinc Phosphate Cement into the roots for each system while another 50 posts were inserted into the canal without using the Cement. After histological sectioning, the Cement gap was measured at six sites for three times at the coronal, middle and apical regions between the root canal wall and the post surface under a light microscope before and after Cementation. Results. Before Cementation, the highest overall Cement gap was observed with the Dr Mooser post system (R) (46 mu m) and the lowest with the Velva post system (R) and Cylindro-Conical system (R) (30 mu m). Significantly less (P 0.001) compared with Velva-Post (R) (38, 20 mu m) at the coronal and middle part, respectively (Mann-Whitney U-test, Boneferroni correction). Significant differences (P
Belkheir Hammouti - One of the best experts on this subject based on the ideXlab platform.
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Hydratation mechanism of a Zinc Phosphate Cement and development of its mechanical profile
Research on Chemical Intermediates, 2012Co-Authors: M. Jabri, E. Mejdoubi, M. El Gadi, Belkheir HammoutiAbstract:The main objective of this study is to understand the setting mechanism of a Zinc Phosphate Cement and the development of its mechanical hardness. This Cement is widely used in dentistry and is composed of solid phase Cement containing Zinc oxide (ZnO) and aluminium Phosphate AlPO4·nH2O, and then liquid phase Cement which is composed of phosphoric acid and water. The setting of the Cement is due to a mixture of both phases together. In this optic, the control of the effect of different compounds in setting mechanism and hardness is carried out by using several investigation methods such as ESM, XRD, IR, TGA, and DTA. For this study, we explain in detail each phase of the Cement process, such as the preparation of raw materials, their mixing, the introduction of the solid phase of Cement to the liquid phase, and then the hardening of the Cement. The results obtained show the effect of powder size on the setting reaction of the Cement and show that aluminium Phosphate had an interesting effect on the hardening and setting time of the Cement. The X-ray diffraction showed that the principal phase of the hydratation product, which is Hopeite, is available in the mixture of initial reactants and other secondary products, which are Zinc Phosphate salts in primary and secondary forms.
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Optimisation of hardness and setting time of dental Zinc Phosphate Cement using a design of experiments
Arabian Journal of Chemistry, 2012Co-Authors: M. Jabri, E. Mejdoubi, M. El Gadi, Belkheir HammoutiAbstract:Abstract The main objective of this study is to demonstrate the application of strategy of an experiment design to optimize the compressive strength and setting time of Zinc Phosphate Cement used in the dental application. For this work, the extreme vertices design was chosen. Its factors are components of the mixture forming a ternary system: Zinc oxide, aluminum Phosphate and orthophosphoric acid (ZnO–AlPO 4 –H 3 PO 4 ). The local region of dental Cement – in simplex space- explored and limited by upper and lower limits of the three components of the mixture. The optimization of each response and then all together by graphical methods allowed us to obtain the adequate Cement.
Akbar Zadeh Baghban Alireza - One of the best experts on this subject based on the ideXlab platform.
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Cytotoxicity Comparison of Harvard Zinc Phosphate Cement Versus Panavia F2 and Rely X Plus Resin Cements on Rat L929-fibroblasts
Cell journal, 2011Co-Authors: Sahabi Mahasti, Sattari Mandana, Romoozi Elham, Akbar Zadeh Baghban AlirezaAbstract:Objective: Resin Cements, regardless of their biocompatibility, have been widely used in restorative dentistry during the recent years. These Cements contain hydroxy ethyl methacrylate (HEMA) molecules which are claimed to penetrate into dentinal tubules and may affect dental pulp. Since tooth preparation for metal ceramic restorations involves a large surface of the tooth, cytotoxicity of these Cements would be more important in fixed prosthodontic treatments. The purpose of this study was to compare the cytotoxicity of two resin Cements (Panavia F2 and Rely X Plus) versus Zinc Phosphate Cement (Harvard) using rat L929-fibroblasts in vitro. Materials and Methods: In this experimental study, ninety hollow glass cylinders (internal diameter 5-mm, height 2-mm) were made and divided into three groups. Each group was filled with one of three experimental Cements; Harvard Zinc Phosphate Cement, Panavia F2 resin Cement and Rely X Plus resin Cement. L929- Fibroblast were passaged and subsequently cultured in 6-well plates of 5×10 5 cells each. The culture medium was RPMI_ 1640. All samples were incubated in CO 2 . Using enzyme-linked immune-sorbent assay (ELISA) and (3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) (MTT) assay, the cytotoxicity of the Cements was investigated at 1 hour, 24 hours and one week post exposure. Statistical analyses were performed via two-way ANOVA and honestly significant difference (HSD) Tukey tests. Results: This study revealed significant differences between the three Cements at the different time intervals. Harvard Cement displayed the greatest cytotoxicity at all three intervals. After 1 hour Panavia F2 showed the next greatest cytotoxicity, but after 24-hours and oneweek intervals Rely X Plus showed the next greatest cytotoxicity. The results further showed that cytotoxicity decreased significantly in the Panavia F2 group with time (p
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cytotoxicity comparison of harvard Zinc Phosphate Cement versus panavia f2 and rely x plus resin Cements on rat l929 fibroblasts
Cell, 2011Co-Authors: Sahabi Mahasti, Sattari Mandana, Romoozi Elham, Akbar Zadeh Baghban AlirezaAbstract:Objective: Resin Cements, regardless of their biocompatibility, have been widely used in restorative dentistry during the recent years. These Cements contain hydroxy ethyl methacrylate (HEMA) molecules which are claimed to penetrate into dentinal tubules and may affect dental pulp. Since tooth preparation for metal ceramic restorations involves a large surface of the tooth, cytotoxicity of these Cements would be more important in fixed prosthodontic treatments. The purpose of this study was to compare the cytotoxicity of two resin Cements (Panavia F2 and Rely X Plus) versus Zinc Phosphate Cement (Harvard) using rat L929-fibroblasts in vitro. Materials and Methods: In this experimental study, ninety hollow glass cylinders (internal diameter 5-mm, height 2-mm) were made and divided into three groups. Each group was filled with one of three experimental Cements; Harvard Zinc Phosphate Cement, Panavia F2 resin Cement and Rely X Plus resin Cement. L929- Fibroblast were passaged and subsequently cultured in 6-well plates of 5×10 5 cells each. The culture medium was RPMI_ 1640. All samples were incubated in CO 2 . Using enzyme-linked immune-sorbent assay (ELISA) and (3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) (MTT) assay, the cytotoxicity of the Cements was investigated at 1 hour, 24 hours and one week post exposure. Statistical analyses were performed via two-way ANOVA and honestly significant difference (HSD) Tukey tests. Results: This study revealed significant differences between the three Cements at the different time intervals. Harvard Cement displayed the greatest cytotoxicity at all three intervals. After 1 hour Panavia F2 showed the next greatest cytotoxicity, but after 24-hours and oneweek intervals Rely X Plus showed the next greatest cytotoxicity. The results further showed that cytotoxicity decreased significantly in the Panavia F2 group with time (p<0.005), cytotoxicity increased significantly in the Rely X Plus group with time (p<0.001), and the Harvard Cement group failed to showed no noticeable change in cytotoxicity with time. Conclusion: Although this study has limitations, it provides evidence that Harvard Zinc Phosphate Cement is the most cytotoxic product and Panavia F2 appears to be the least cytotoxic Cement over time.
Steven R. Jefferies - One of the best experts on this subject based on the ideXlab platform.
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Effects of a 36% tooth bleaching gel on Zinc Phosphate Cement.
Journal of biomedical materials research. Part B Applied biomaterials, 2010Co-Authors: Daniel W. Boston, Steven R. JefferiesAbstract:Purpose: To assess the effect of a 36% hydrogen peroxide bleaching gel on the roughness, microhardness, indentation modulus, and micromorphology of Zinc Phosphate Cement aged 24 h or 1 week, compared to Cement not exposed to bleaching gel. Methods: Dynamic indentation was performed for microhardness and indentation modulus. Contact profilometry was performed for surface roughness. Scanning electron microscopy assessed micromorphology. Means for microhardness, indentation modulus, and roughness were analyzed for differences among groups (No. 1 = 24 h/control; No. 2 = 24 h/treatment; No. 3 = 1 week/control; No. 4 = 1 week/treatment). Results: Means (SD) for groups 1–4 respectively: Vickers Microhardness (HV): 34.2(8.7)a, 32.8(10.9)a, 24.8(5.0)b, 41.5(7.4)c; Indentation Modulus (EIT, GPa): 14.2(6.9)a,b, 10.6(3.6)a, 11.2(3.8)a, 14.7(2.8)b; and Surface Roughness (Ra, microns): 1.08(0.38)a, 1.21(0.55)a, 1.55(0.21)b, 1.52(0.29)b. Means labeled with the same superscript were not statistically significantly different. Scanning electron microscopy of groups 1 and 2 revealed similar details. Group 3 surfaces had plate-like crystals not present on the group 4 surfaces. Conclusions: Bleaching gel exposure increased hardness and indentation modulus and caused limited changes in surface morphology, but the Cement was not adversely affected by the bleaching protocol. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010
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effects of a 36 tooth bleaching gel on Zinc Phosphate Cement
Journal of Biomedical Materials Research Part B, 2009Co-Authors: Daniel W. Boston, Steven R. JefferiesAbstract:Purpose: To assess the effect of a 36% hydrogen peroxide bleaching gel on the roughness, microhardness, indentation modulus, and micromorphology of Zinc Phosphate Cement aged 24 h or 1 week, compared to Cement not exposed to bleaching gel. Methods: Dynamic indentation was performed for microhardness and indentation modulus. Contact profilometry was performed for surface roughness. Scanning electron microscopy assessed micromorphology. Means for microhardness, indentation modulus, and roughness were analyzed for differences among groups (No. 1 = 24 h/control; No. 2 = 24 h/treatment; No. 3 = 1 week/control; No. 4 = 1 week/treatment). Results: Means (SD) for groups 1–4 respectively: Vickers Microhardness (HV): 34.2(8.7)a, 32.8(10.9)a, 24.8(5.0)b, 41.5(7.4)c; Indentation Modulus (EIT, GPa): 14.2(6.9)a,b, 10.6(3.6)a, 11.2(3.8)a, 14.7(2.8)b; and Surface Roughness (Ra, microns): 1.08(0.38)a, 1.21(0.55)a, 1.55(0.21)b, 1.52(0.29)b. Means labeled with the same superscript were not statistically significantly different. Scanning electron microscopy of groups 1 and 2 revealed similar details. Group 3 surfaces had plate-like crystals not present on the group 4 surfaces. Conclusions: Bleaching gel exposure increased hardness and indentation modulus and caused limited changes in surface morphology, but the Cement was not adversely affected by the bleaching protocol. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010
Petra Schmage - One of the best experts on this subject based on the ideXlab platform.
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the fit of tapered posts in root canals luted with Zinc Phosphate Cement a histological study
Dental Materials, 2005Co-Authors: Petra Schmage, Mutlu Özcan, Candice Mcmullanvogel, Ibrahim NergizAbstract:Objectives. Stress transmission to the root through passive fitting dental posts is partly influenced by the thickness of the Cement layer between the post and the prepared root canal surface as well as the fit of the post in the root canal. The objective of this study was to compare the Cement gap between the post surfaces and the root canals using five prefabricated, tapered, unthreaded titanium posts of different manufacturers, without and with Cement. Methods. Following the endodontic treatment with hand instruments of 100 intact anterior teeth, post spaces were prepared using opening drills of the corresponding size of post. Fifty posts were Cemented with Zinc Phosphate Cement into the roots for each system while another 50 posts were inserted into the canal without using the Cement. After histological sectioning, the Cement gap was measured at six sites for three times at the coronal, middle and apical regions between the root canal wall and the post surface under a light microscope before and after Cementation. Results. Before Cementation, the highest overall Cement gap was observed with the Dr Mooser post system (R) (46 mu m) and the lowest with the Velva post system (R) and Cylindro-Conical system (R) (30 mu m). Significantly less (P 0.001) compared with Velva-Post (R) (38, 20 mu m) at the coronal and middle part, respectively (Mann-Whitney U-test, Boneferroni correction). Significant differences (P <0.001) were observed between the Cement gap at the coronal and apical part for the Cylindro-Conical system (R) (79, 46 mu m), Dr Mooser post system (R) (45, 56 mu m) and MP Pirec post system (R) (25, 52 mu m). After Cementation, the highest Cement gap at the coronal part was obtained with the Cylindro-Conical system (R) (79 +/- 21 mu m) and the lowest with the MP Pirec post system (R) (25 +/- 9 mu m). However, at the apical end, the MP Pirec post system (R) (52 +/- 89 gm) and Dr Mooser post system (R) (56 +/- 16 gm) revealed the highest gap. Significance. Form-congruence between the preparation drill and the post systems exhibited differences. The most consistent Cement gap either at the coronal, middle or apical parts of the root canals was obtained with the Erlangen post system (R). (c) 2005 Academy of Dental Materials. Published by Elsevier Ltd. All. rights reserved.
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The fit of tapered posts in root canals luted with Zinc Phosphate Cement: A histological study
Dental materials : official publication of the Academy of Dental Materials, 2005Co-Authors: Petra Schmage, Mutlu Özcan, Candice G. Mcmullan-vogel, Ibrahim NergizAbstract:Objectives. Stress transmission to the root through passive fitting dental posts is partly influenced by the thickness of the Cement layer between the post and the prepared root canal surface as well as the fit of the post in the root canal. The objective of this study was to compare the Cement gap between the post surfaces and the root canals using five prefabricated, tapered, unthreaded titanium posts of different manufacturers, without and with Cement. Methods. Following the endodontic treatment with hand instruments of 100 intact anterior teeth, post spaces were prepared using opening drills of the corresponding size of post. Fifty posts were Cemented with Zinc Phosphate Cement into the roots for each system while another 50 posts were inserted into the canal without using the Cement. After histological sectioning, the Cement gap was measured at six sites for three times at the coronal, middle and apical regions between the root canal wall and the post surface under a light microscope before and after Cementation. Results. Before Cementation, the highest overall Cement gap was observed with the Dr Mooser post system (R) (46 mu m) and the lowest with the Velva post system (R) and Cylindro-Conical system (R) (30 mu m). Significantly less (P 0.001) compared with Velva-Post (R) (38, 20 mu m) at the coronal and middle part, respectively (Mann-Whitney U-test, Boneferroni correction). Significant differences (P
