15-Crown-5

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Malgorzata Joźwiak - One of the best experts on this subject based on the ideXlab platform.

  • the effect of properties of water organic solvent mixtures on the solvation enthalpy of 12 crown 4 15 crown 5 18 crown 6 and benzo 15 crown 5 ethers at 298 15 k
    2004
    Co-Authors: Malgorzata Joźwiak
    Abstract:

    Abstract Crown ethers are preferential solvated by organic solvents in the mixtures of water with formamide, N -methylformamide, acetonitrile, acetone and propan-1-ol. In these mixed solvents the energetic effect of the preferential solvation depends quantitatively on the structural and energetic properties of mixtures. The energetic properties of the mixtures of water with hydrophobic solvents ( N , N -dimethylformamide, dimethylsulfoxide, N , N -dimethylacetamide, hexamethylphosphortriamide) counteract the preferential solvation of the crown ether molecules. The effect of the hydrophobic and acid–base properties of the mixture of water with organic solvent on the solvation of 12-crown-4, 15-Crown-5, 18-crown-6 and benzo-15-Crown-5 ethers was discussed. The solvation enthalpy of one –CH 2 CH 2 O– group in water, N,N -dimethylformamide and hexamethylphosphortriamide is equal to −24.21, −16.04 and −15.91 kJ/mol, respectively. The condensed benzene ring with 15-Crown-5 ether molecule brings about an increase in the exothermic effect of solvation of the crown ether in the mixtures of water with organic solvent.

  • thermochemical behaviour of crown ethers in the mixtures of water with organic solvents part vii enthalpy of solution of 15 crown 5 and benzo 15 crown 5 in the mixtures of water with acetone at 298 15 k
    2004
    Co-Authors: Malgorzata Joźwiak
    Abstract:

    Abstract Enthalpy of solution of crown ethers (15-Crown-5 and benzo-15-Crown-5) in water–acetone mixtures have been measured within the whole range of mole fraction at 298.15 K. The obtained data have been compared with those of the solution enthalpy of both crown ethers in the mixtures of water with dimethyl sulfoxide. The replacement of SO group with CO in the molecule of the organic solvent brings about an increase in the exothermic effect of the solution of 15-Crown-5 and benzo-15-Crown-5 ethers, especially in the mixtures with a medium water content. The observed effect is connected with the preferential solvation of the molecules of both crown ethers by acetone molecules in the water–acetone mixtures. The process of preferential solvation of 15-Crown-5 and benzo-15-Crown-5 ethers does not take place in the water–dimethyl sulfoxide mixture.

Oleg Admakin - One of the best experts on this subject based on the ideXlab platform.

  • a novel full digital protocol scan plan make done for the design and fabrication of implant supported monolithic translucent zirconia crowns cemented on customized hybrid abutments a retrospective clinical study on 25 patients
    2019
    Co-Authors: Francesco Mangano, Bidzina Margiani, Oleg Admakin
    Abstract:

    Purpose: To present a novel, full-digital protocol for the design and fabrication of implant-supported monolithic translucent zirconia crowns cemented on customized hybrid abutments. Methods: The present retrospective clinical study was based on data from patients who had been treated with single Morse-taper connection implants (Exacone®, Leone Implants, Florence, Italy) and were prosthetically restored with monolithic translucent zirconia crowns, cemented on customized hybrid abutments. The full-digital protocol (SCAN-PLAN-MAKE-DONE®) consisted of 8 phases: (1) intraoral scan of the implant position with scanbody; (2) computer-assisted design (CAD) of the individual abutment (saved as “supplementary abutment design” in external folder) and temporary crown; (3) milling of the individual zirconia abutment and of the temporary polymethyl-methacrylate (PMMA) crown, with extraoral cementation of the zirconia abutment on the relative titanium bonding base, to generate an individual hybrid abutment; (4) clinical application of the individual hybrid abutment and cementation of the temporary PMMA crown; (5) two months later, intraoral scan of the individual hybrid abutment in position; (6) CAD of the final crown with margin line design on the previously saved “supplementary abutment design”, superimposed on the second scan of the abutment in position; (7) milling of the final crown in monolithic translucent zirconia, sintering, and characterization; and (8) clinical application of the final crown. All patients were followed for a period of 1 year. The primary outcomes of this study were the marginal adaptation of the final crown (checked clinically and radiographically), the quality of occlusal and interproximal contact points at delivery, and the aesthetic integration; the secondary outcomes were the 1-year survival and success of the implant-supported restoration. An implant-supported restoration was considered successful in the absence of any biological or prosthetic complication, during the entire follow-up period. Results: In total, 25 patients (12 males, 13 females; 26–74 years of age; mean age 51.1 ± 13.3 years) who had been restored with 40 implant-supported monolithic translucent zirconia crowns were included in this study. At delivery, the marginal adaptation was perfect for all crowns. However, there were occlusal issues (2/40 crowns: 5%), interproximal issues (1/40 crowns: 2.5%), and aesthetic issues (1/40 crowns: 2.5%). The overall incidence of issues at delivery was therefore 10% (4/40 crowns). At 1 year, one implant failed; thus the survival of the restorations was 97.5% (39/40 crowns in function). Among the surviving implant-supported restorations, three experienced complications (one loss of connection between the hybrid abutment and the implant, one decementation of the zirconia abutment, and one decementation of the zirconia crown). The success of restorations amounted to 92.4%. Conclusions: The restoration of single Morse-taper connection implants with monolithic translucent zirconia crowns cemented on customized hybrid abutments via the novel SCAN-PLAN-MAKE-DONE® full-digital protocol seems to represent a reliable treatment option. However, further studies on a larger number of patients and dealing with different prosthetic restorations (such as implant-supported fixed partial prostheses) are needed to confirm the validity of this protocol.

  • A Novel Full-Digital Protocol (SCAN-PLAN-MAKE-DONE®) for the Design and Fabrication of Implant-Supported Monolithic Translucent Zirconia Crowns Cemented on Customized Hybrid Abutments: A Retrospective Clinical Study on 25 Patients
    2019
    Co-Authors: Francesco Mangano, Bidzina Margiani, Oleg Admakin
    Abstract:

    Purpose: To present a novel, full-digital protocol for the design and fabrication of implant-supported monolithic translucent zirconia crowns cemented on customized hybrid abutments. Methods: The present retrospective clinical study was based on data from patients who had been treated with single Morse-taper connection implants (Exacone®, Leone Implants, Florence, Italy) and were prosthetically restored with monolithic translucent zirconia crowns, cemented on customized hybrid abutments. The full-digital protocol (SCAN-PLAN-MAKE-DONE®) consisted of 8 phases: (1) intraoral scan of the implant position with scanbody; (2) computer-assisted design (CAD) of the individual abutment (saved as “supplementary abutment design„ in external folder) and temporary crown; (3) milling of the individual zirconia abutment and of the temporary polymethyl-methacrylate (PMMA) crown, with extraoral cementation of the zirconia abutment on the relative titanium bonding base, to generate an individual hybrid abutment; (4) clinical application of the individual hybrid abutment and cementation of the temporary PMMA crown; (5) two months later, intraoral scan of the individual hybrid abutment in position; (6) CAD of the final crown with margin line design on the previously saved “supplementary abutment design„, superimposed on the second scan of the abutment in position; (7) milling of the final crown in monolithic translucent zirconia, sintering, and characterization; and (8) clinical application of the final crown. All patients were followed for a period of 1 year. The primary outcomes of this study were the marginal adaptation of the final crown (checked clinically and radiographically), the quality of occlusal and interproximal contact points at delivery, and the aesthetic integration; the secondary outcomes were the 1-year survival and success of the implant-supported restoration. An implant-supported restoration was considered successful in the absence of any biological or prosthetic complication, during the entire follow-up period. Results: In total, 25 patients (12 males, 13 females; 26⁻74 years of age; mean age 51.1 ± 13.3 years) who had been restored with 40 implant-supported monolithic translucent zirconia crowns were included in this study. At delivery, the marginal adaptation was perfect for all crowns. However, there were occlusal issues (2/40 crowns: 5%), interproximal issues (1/40 crowns: 2.5%), and aesthetic issues (1/40 crowns: 2.5%). The overall incidence of issues at delivery was therefore 10% (4/40 crowns). At 1 year, one implant failed; thus the survival of the restorations was 97.5% (39/40 crowns in function). Among the surviving implant-supported restorations, three experienced complications (one loss of connection between the hybrid abutment and the implant, one decementation of the zirconia abutment, and one decementation of the zirconia crown). The success of restorations amounted to 92.4%. Conclusions: The restoration of single Morse-taper connection implants with monolithic translucent zirconia crowns cemented on customized hybrid abutments via the novel SCAN-PLAN-MAKE-DONE® full-digital protocol seems to represent a reliable treatment option. However, further studies on a larger number of patients and dealing with different prosthetic restorations (such as implant-supported fixed partial prostheses) are needed to confirm the validity of this protocol

Francesco Mangano - One of the best experts on this subject based on the ideXlab platform.

  • a novel full digital protocol scan plan make done for the design and fabrication of implant supported monolithic translucent zirconia crowns cemented on customized hybrid abutments a retrospective clinical study on 25 patients
    2019
    Co-Authors: Francesco Mangano, Bidzina Margiani, Oleg Admakin
    Abstract:

    Purpose: To present a novel, full-digital protocol for the design and fabrication of implant-supported monolithic translucent zirconia crowns cemented on customized hybrid abutments. Methods: The present retrospective clinical study was based on data from patients who had been treated with single Morse-taper connection implants (Exacone®, Leone Implants, Florence, Italy) and were prosthetically restored with monolithic translucent zirconia crowns, cemented on customized hybrid abutments. The full-digital protocol (SCAN-PLAN-MAKE-DONE®) consisted of 8 phases: (1) intraoral scan of the implant position with scanbody; (2) computer-assisted design (CAD) of the individual abutment (saved as “supplementary abutment design” in external folder) and temporary crown; (3) milling of the individual zirconia abutment and of the temporary polymethyl-methacrylate (PMMA) crown, with extraoral cementation of the zirconia abutment on the relative titanium bonding base, to generate an individual hybrid abutment; (4) clinical application of the individual hybrid abutment and cementation of the temporary PMMA crown; (5) two months later, intraoral scan of the individual hybrid abutment in position; (6) CAD of the final crown with margin line design on the previously saved “supplementary abutment design”, superimposed on the second scan of the abutment in position; (7) milling of the final crown in monolithic translucent zirconia, sintering, and characterization; and (8) clinical application of the final crown. All patients were followed for a period of 1 year. The primary outcomes of this study were the marginal adaptation of the final crown (checked clinically and radiographically), the quality of occlusal and interproximal contact points at delivery, and the aesthetic integration; the secondary outcomes were the 1-year survival and success of the implant-supported restoration. An implant-supported restoration was considered successful in the absence of any biological or prosthetic complication, during the entire follow-up period. Results: In total, 25 patients (12 males, 13 females; 26–74 years of age; mean age 51.1 ± 13.3 years) who had been restored with 40 implant-supported monolithic translucent zirconia crowns were included in this study. At delivery, the marginal adaptation was perfect for all crowns. However, there were occlusal issues (2/40 crowns: 5%), interproximal issues (1/40 crowns: 2.5%), and aesthetic issues (1/40 crowns: 2.5%). The overall incidence of issues at delivery was therefore 10% (4/40 crowns). At 1 year, one implant failed; thus the survival of the restorations was 97.5% (39/40 crowns in function). Among the surviving implant-supported restorations, three experienced complications (one loss of connection between the hybrid abutment and the implant, one decementation of the zirconia abutment, and one decementation of the zirconia crown). The success of restorations amounted to 92.4%. Conclusions: The restoration of single Morse-taper connection implants with monolithic translucent zirconia crowns cemented on customized hybrid abutments via the novel SCAN-PLAN-MAKE-DONE® full-digital protocol seems to represent a reliable treatment option. However, further studies on a larger number of patients and dealing with different prosthetic restorations (such as implant-supported fixed partial prostheses) are needed to confirm the validity of this protocol.

  • A Novel Full-Digital Protocol (SCAN-PLAN-MAKE-DONE®) for the Design and Fabrication of Implant-Supported Monolithic Translucent Zirconia Crowns Cemented on Customized Hybrid Abutments: A Retrospective Clinical Study on 25 Patients
    2019
    Co-Authors: Francesco Mangano, Bidzina Margiani, Oleg Admakin
    Abstract:

    Purpose: To present a novel, full-digital protocol for the design and fabrication of implant-supported monolithic translucent zirconia crowns cemented on customized hybrid abutments. Methods: The present retrospective clinical study was based on data from patients who had been treated with single Morse-taper connection implants (Exacone®, Leone Implants, Florence, Italy) and were prosthetically restored with monolithic translucent zirconia crowns, cemented on customized hybrid abutments. The full-digital protocol (SCAN-PLAN-MAKE-DONE®) consisted of 8 phases: (1) intraoral scan of the implant position with scanbody; (2) computer-assisted design (CAD) of the individual abutment (saved as “supplementary abutment design„ in external folder) and temporary crown; (3) milling of the individual zirconia abutment and of the temporary polymethyl-methacrylate (PMMA) crown, with extraoral cementation of the zirconia abutment on the relative titanium bonding base, to generate an individual hybrid abutment; (4) clinical application of the individual hybrid abutment and cementation of the temporary PMMA crown; (5) two months later, intraoral scan of the individual hybrid abutment in position; (6) CAD of the final crown with margin line design on the previously saved “supplementary abutment design„, superimposed on the second scan of the abutment in position; (7) milling of the final crown in monolithic translucent zirconia, sintering, and characterization; and (8) clinical application of the final crown. All patients were followed for a period of 1 year. The primary outcomes of this study were the marginal adaptation of the final crown (checked clinically and radiographically), the quality of occlusal and interproximal contact points at delivery, and the aesthetic integration; the secondary outcomes were the 1-year survival and success of the implant-supported restoration. An implant-supported restoration was considered successful in the absence of any biological or prosthetic complication, during the entire follow-up period. Results: In total, 25 patients (12 males, 13 females; 26⁻74 years of age; mean age 51.1 ± 13.3 years) who had been restored with 40 implant-supported monolithic translucent zirconia crowns were included in this study. At delivery, the marginal adaptation was perfect for all crowns. However, there were occlusal issues (2/40 crowns: 5%), interproximal issues (1/40 crowns: 2.5%), and aesthetic issues (1/40 crowns: 2.5%). The overall incidence of issues at delivery was therefore 10% (4/40 crowns). At 1 year, one implant failed; thus the survival of the restorations was 97.5% (39/40 crowns in function). Among the surviving implant-supported restorations, three experienced complications (one loss of connection between the hybrid abutment and the implant, one decementation of the zirconia abutment, and one decementation of the zirconia crown). The success of restorations amounted to 92.4%. Conclusions: The restoration of single Morse-taper connection implants with monolithic translucent zirconia crowns cemented on customized hybrid abutments via the novel SCAN-PLAN-MAKE-DONE® full-digital protocol seems to represent a reliable treatment option. However, further studies on a larger number of patients and dealing with different prosthetic restorations (such as implant-supported fixed partial prostheses) are needed to confirm the validity of this protocol

Bidzina Margiani - One of the best experts on this subject based on the ideXlab platform.

  • a novel full digital protocol scan plan make done for the design and fabrication of implant supported monolithic translucent zirconia crowns cemented on customized hybrid abutments a retrospective clinical study on 25 patients
    2019
    Co-Authors: Francesco Mangano, Bidzina Margiani, Oleg Admakin
    Abstract:

    Purpose: To present a novel, full-digital protocol for the design and fabrication of implant-supported monolithic translucent zirconia crowns cemented on customized hybrid abutments. Methods: The present retrospective clinical study was based on data from patients who had been treated with single Morse-taper connection implants (Exacone®, Leone Implants, Florence, Italy) and were prosthetically restored with monolithic translucent zirconia crowns, cemented on customized hybrid abutments. The full-digital protocol (SCAN-PLAN-MAKE-DONE®) consisted of 8 phases: (1) intraoral scan of the implant position with scanbody; (2) computer-assisted design (CAD) of the individual abutment (saved as “supplementary abutment design” in external folder) and temporary crown; (3) milling of the individual zirconia abutment and of the temporary polymethyl-methacrylate (PMMA) crown, with extraoral cementation of the zirconia abutment on the relative titanium bonding base, to generate an individual hybrid abutment; (4) clinical application of the individual hybrid abutment and cementation of the temporary PMMA crown; (5) two months later, intraoral scan of the individual hybrid abutment in position; (6) CAD of the final crown with margin line design on the previously saved “supplementary abutment design”, superimposed on the second scan of the abutment in position; (7) milling of the final crown in monolithic translucent zirconia, sintering, and characterization; and (8) clinical application of the final crown. All patients were followed for a period of 1 year. The primary outcomes of this study were the marginal adaptation of the final crown (checked clinically and radiographically), the quality of occlusal and interproximal contact points at delivery, and the aesthetic integration; the secondary outcomes were the 1-year survival and success of the implant-supported restoration. An implant-supported restoration was considered successful in the absence of any biological or prosthetic complication, during the entire follow-up period. Results: In total, 25 patients (12 males, 13 females; 26–74 years of age; mean age 51.1 ± 13.3 years) who had been restored with 40 implant-supported monolithic translucent zirconia crowns were included in this study. At delivery, the marginal adaptation was perfect for all crowns. However, there were occlusal issues (2/40 crowns: 5%), interproximal issues (1/40 crowns: 2.5%), and aesthetic issues (1/40 crowns: 2.5%). The overall incidence of issues at delivery was therefore 10% (4/40 crowns). At 1 year, one implant failed; thus the survival of the restorations was 97.5% (39/40 crowns in function). Among the surviving implant-supported restorations, three experienced complications (one loss of connection between the hybrid abutment and the implant, one decementation of the zirconia abutment, and one decementation of the zirconia crown). The success of restorations amounted to 92.4%. Conclusions: The restoration of single Morse-taper connection implants with monolithic translucent zirconia crowns cemented on customized hybrid abutments via the novel SCAN-PLAN-MAKE-DONE® full-digital protocol seems to represent a reliable treatment option. However, further studies on a larger number of patients and dealing with different prosthetic restorations (such as implant-supported fixed partial prostheses) are needed to confirm the validity of this protocol.

  • A Novel Full-Digital Protocol (SCAN-PLAN-MAKE-DONE®) for the Design and Fabrication of Implant-Supported Monolithic Translucent Zirconia Crowns Cemented on Customized Hybrid Abutments: A Retrospective Clinical Study on 25 Patients
    2019
    Co-Authors: Francesco Mangano, Bidzina Margiani, Oleg Admakin
    Abstract:

    Purpose: To present a novel, full-digital protocol for the design and fabrication of implant-supported monolithic translucent zirconia crowns cemented on customized hybrid abutments. Methods: The present retrospective clinical study was based on data from patients who had been treated with single Morse-taper connection implants (Exacone®, Leone Implants, Florence, Italy) and were prosthetically restored with monolithic translucent zirconia crowns, cemented on customized hybrid abutments. The full-digital protocol (SCAN-PLAN-MAKE-DONE®) consisted of 8 phases: (1) intraoral scan of the implant position with scanbody; (2) computer-assisted design (CAD) of the individual abutment (saved as “supplementary abutment design„ in external folder) and temporary crown; (3) milling of the individual zirconia abutment and of the temporary polymethyl-methacrylate (PMMA) crown, with extraoral cementation of the zirconia abutment on the relative titanium bonding base, to generate an individual hybrid abutment; (4) clinical application of the individual hybrid abutment and cementation of the temporary PMMA crown; (5) two months later, intraoral scan of the individual hybrid abutment in position; (6) CAD of the final crown with margin line design on the previously saved “supplementary abutment design„, superimposed on the second scan of the abutment in position; (7) milling of the final crown in monolithic translucent zirconia, sintering, and characterization; and (8) clinical application of the final crown. All patients were followed for a period of 1 year. The primary outcomes of this study were the marginal adaptation of the final crown (checked clinically and radiographically), the quality of occlusal and interproximal contact points at delivery, and the aesthetic integration; the secondary outcomes were the 1-year survival and success of the implant-supported restoration. An implant-supported restoration was considered successful in the absence of any biological or prosthetic complication, during the entire follow-up period. Results: In total, 25 patients (12 males, 13 females; 26⁻74 years of age; mean age 51.1 ± 13.3 years) who had been restored with 40 implant-supported monolithic translucent zirconia crowns were included in this study. At delivery, the marginal adaptation was perfect for all crowns. However, there were occlusal issues (2/40 crowns: 5%), interproximal issues (1/40 crowns: 2.5%), and aesthetic issues (1/40 crowns: 2.5%). The overall incidence of issues at delivery was therefore 10% (4/40 crowns). At 1 year, one implant failed; thus the survival of the restorations was 97.5% (39/40 crowns in function). Among the surviving implant-supported restorations, three experienced complications (one loss of connection between the hybrid abutment and the implant, one decementation of the zirconia abutment, and one decementation of the zirconia crown). The success of restorations amounted to 92.4%. Conclusions: The restoration of single Morse-taper connection implants with monolithic translucent zirconia crowns cemented on customized hybrid abutments via the novel SCAN-PLAN-MAKE-DONE® full-digital protocol seems to represent a reliable treatment option. However, further studies on a larger number of patients and dealing with different prosthetic restorations (such as implant-supported fixed partial prostheses) are needed to confirm the validity of this protocol

Carolyn Pratt Brock - One of the best experts on this subject based on the ideXlab platform.

  • the elusive ni h2o 2 15 crown 5 2 cation and related co crystals of nickel ii hydrates and 15 crown 5
    2008
    Co-Authors: Maxime A Siegler, Sean Parkin, John P Selegue, Carolyn Pratt Brock
    Abstract:

    Initial attempts to make [Ni(H2O)2(15-Crown-5)](NO3)2, i.e. to insert the Ni2+ ion into the 15-Crown-5 macrocycle, gave the mono- (two polymorphs) and dihydrate of a co-crystal of [Ni(H2O)6](NO3)2 and 15-Crown-5 (1,4,7,10,13-pentaoxacyclopentadecane = 15C5). Synthetic routes designed to restrict the water available to the Ni2+ cation gave three additional compounds, [Ni(H2O)6](NO3)2-trans-[Ni(H2O)4(MeOH)2](NO3)2·2(15C5), cis-[Ni(H2O)4(NO3)2]-trans-[Ni(H2O)4(NO3)2]·2(15C5) and [Ni(H2O)2(MeCN)(NO3)2]·15C5·MeCN. All five compounds contain Ni2+ ions with two trans aqua ligands. In all six structures these aqua ligands make hydrogen bonds to the 15C5 molecules to form stacks in which the Ni complexes and 15C5 molecules alternate. The structures are surprisingly complicated: all are co-crystals, some are also solvates, and most have Z′ > 1. The target compound was finally prepared by heating pale green crystals of [Ni(H2O)6](NO3)2·15C5·2H2O to over 350 K and then cooling the resulting mixture of yellow crystals and solution to room temperature. Formation of the target compound seems to be favored at higher temperatures by a positive ΔrxnSo and an increased rate of ligand exchange.