The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Ava K Chow - One of the best experts on this subject based on the ideXlab platform.
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surface detail reproduction and effect of disinfectant and long term storage on the Dimensional Stability of a novel vinyl polyether silicone impression material
Journal of Prosthodontics, 2015Co-Authors: Usama Nassar, Ava K ChowAbstract:Purpose This study investigated the surface detail reproduction and Dimensional Stability of a vinyl polyether silicone (VPES) in comparison to a vinylpolysiloxane (VPS) material as a function of prolonged storage for up to 2 weeks. Materials and Methods Heavy-body VPES (EXA'lenceTM Fast Set) and VPS (ImprintTM 3 Quick Step) were compared. Forty impression ingots of each material were made using a stainless steel die as described by ANSI/ADA specification No. 19. Twenty impressions of each material were disinfected by immersion in a 2.5% buffered glutaraldehyde solution. Surface quality was assessed and scored immediately after making the ingots. Dimensional Stability measurements were made immediately and repeated on the same ingots after 7 and 14 days storage in ambient laboratory conditions. Data were analyzed using the D'Agostino and Pearson omnibus normality test followed by two-way repeated measures ANOVA with post hoc Bonferroni tests. Values of p < 0.01 were deemed to be significant. Results Disinfected VPES and VPS specimens had significantly reduced Dimensional changes at 7 and 14 days when compared with the nondisinfected ones (p < 0.0001). The Dimensional Stability of both materials was within ANSI/ADA specification No. 19's acceptable limit throughout the 2-week test period, regardless of whether they were disinfected. Out of the initial 80 ingots, 8 VPES and 1 VPS ingot scored a 2 on the surface detail test, while the remaining 71 ingots scored 1. Conclusions Heavy-body fast-set VPES experienced minimal contraction in vitro after prolonged storage, though surface detail scores were not as consistent as those of the VPS tested. The least contraction occurred when the material was examined immediately after ingot production.
Usama Nassar - One of the best experts on this subject based on the ideXlab platform.
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surface detail reproduction and effect of disinfectant and long term storage on the Dimensional Stability of a novel vinyl polyether silicone impression material
Journal of Prosthodontics, 2015Co-Authors: Usama Nassar, Ava K ChowAbstract:Purpose This study investigated the surface detail reproduction and Dimensional Stability of a vinyl polyether silicone (VPES) in comparison to a vinylpolysiloxane (VPS) material as a function of prolonged storage for up to 2 weeks. Materials and Methods Heavy-body VPES (EXA'lenceTM Fast Set) and VPS (ImprintTM 3 Quick Step) were compared. Forty impression ingots of each material were made using a stainless steel die as described by ANSI/ADA specification No. 19. Twenty impressions of each material were disinfected by immersion in a 2.5% buffered glutaraldehyde solution. Surface quality was assessed and scored immediately after making the ingots. Dimensional Stability measurements were made immediately and repeated on the same ingots after 7 and 14 days storage in ambient laboratory conditions. Data were analyzed using the D'Agostino and Pearson omnibus normality test followed by two-way repeated measures ANOVA with post hoc Bonferroni tests. Values of p < 0.01 were deemed to be significant. Results Disinfected VPES and VPS specimens had significantly reduced Dimensional changes at 7 and 14 days when compared with the nondisinfected ones (p < 0.0001). The Dimensional Stability of both materials was within ANSI/ADA specification No. 19's acceptable limit throughout the 2-week test period, regardless of whether they were disinfected. Out of the initial 80 ingots, 8 VPES and 1 VPS ingot scored a 2 on the surface detail test, while the remaining 71 ingots scored 1. Conclusions Heavy-body fast-set VPES experienced minimal contraction in vitro after prolonged storage, though surface detail scores were not as consistent as those of the VPS tested. The least contraction occurred when the material was examined immediately after ingot production.
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an in vitro study on the Dimensional Stability of a vinyl polyether silicone impression material over a prolonged storage period
Journal of Prosthetic Dentistry, 2013Co-Authors: Usama Nassar, Marwan Elrich, Samer Adeeb, Carlos FloresmirAbstract:Statement of problem A new elastomeric impression material, a vinyl polyether silicone, has been commercially introduced. Its Dimensional Stability at different pouring times has not been reported. Purpose The purpose of this study was to evaluate the Dimensional Stability of vinyl polyether silicone (VPES) impressions as a function of delayed-pouring time for up to 2 weeks after performing a recommended clinical disinfection procedure. Material and methods The 3 medium-body impression materials tested were EXA'lence 370, Imprint 3, and Impregum Penta soft. Impressions of a cylindrical metal model, which served as a control, were made and poured in a Type V stone after being disinfected in 2.5% buffered glutaraldehyde solution. Die diameter and anteroposterior and cross-arch measurements on each cast were made and compared to direct measurements of the control with a digital micrometer. The linear Dimensional changes were compared and analyzed by using the Mann-Whitney U test (α=.05). Results Considering the absolute values for the mean percentage Dimensional change, VPES cast measurements were below 1.0% ( P Conclusions Casts produced from a disinfected regular set VPES (EXA'lence 370 monophase) demonstrated excellent Dimensional Stability at different pour times and were comparable to the tested VPS and PE impression materials.
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an in vitro study on the Dimensional Stability of a vinyl polyether silicone impression material over a prolonged storage period
Journal of Prosthetic Dentistry, 2013Co-Authors: Usama Nassar, Marwan Elrich, Samer Adeeb, Carlos FloresmirAbstract:Statement of problem A new elastomeric impression material, a vinyl polyether silicone, has been commercially introduced. Its Dimensional Stability at different pouring times has not been reported. Purpose The purpose of this study was to evaluate the Dimensional Stability of vinyl polyether silicone (VPES) impressions as a function of delayed-pouring time for up to 2 weeks after performing a recommended clinical disinfection procedure. Material and methods The 3 medium-body impression materials tested were EXA'lence 370, Imprint 3, and Impregum Penta soft. Impressions of a cylindrical metal model, which served as a control, were made and poured in a Type V stone after being disinfected in 2.5% buffered glutaraldehyde solution. Die diameter and anteroposterior and cross-arch measurements on each cast were made and compared to direct measurements of the control with a digital micrometer. The linear Dimensional changes were compared and analyzed by using the Mann-Whitney U test (α=.05). Results Considering the absolute values for the mean percentage Dimensional change, VPES cast measurements were below 1.0% ( P Conclusions Casts produced from a disinfected regular set VPES (EXA'lence 370 monophase) demonstrated excellent Dimensional Stability at different pour times and were comparable to the tested VPS and PE impression materials.
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Dimensional Stability of irreversible hydrocolloid impression materials as a function of pouring time a systematic review
Journal of Prosthetic Dentistry, 2011Co-Authors: Usama Nassar, Tehnia Aziz, Carlos FloresmirAbstract:Statement of problem Pouring time of irreversible hydrocolloid impressions differs depending on the brand and intended use, either of which may result in variable Dimensional Stability. Purpose The purpose of this study was to investigate the available literature on Dimensional Stability of irreversible hydrocolloid impression materials as a function of pouring time and disinfectant solutions used. Material and methods Three electronic database searches (Medline, PubMed, and EMBASE) were conducted to identify in vitro peer-reviewed studies published in English between the early 1970s and October 2010. Selection criteria included in vitro studies, irreversible hydrocolloid as impression material, and storage time. Heterogeneity in the methodology of the selected studies precluded a meta-analysis. Results Of 62 initially selected studies only 18 were included. Traditional irreversible hydrocolloids were generally stable when poured immediately. However, Stability decreased as time elapsed. New irreversible hydrocolloid substitutes appear to allow delay in pouring time and repouring of impressions without significant side effects. Conclusions Shorter storage time of irreversible hydrocolloid impressions before pouring is desirable, although this may not be necessary for the extended-pour types. The lack of a standardized technique for studying the effect of storage condition, with or without the use of disinfectants, makes it difficult to make clear recommendations.
Songlin Yi - One of the best experts on this subject based on the ideXlab platform.
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effects of tung oil treatment on wood hygroscopicity Dimensional Stability and thermoStability
Industrial Crops and Products, 2019Co-Authors: Zhengbin He, Lijie Qu, Jing Qian, Songlin YiAbstract:Abstract It is commonly known that wood is a limited renewable material, and its low Dimensional Stability characteristics limit its ability to be more widely used. Tung oil, which is characterized by environmentally friendly and water-repellent features, is used in this study as a modifier to improve the properties of wood. Wood is impregnated with Tung oil at room temperature, and the effects of Tung oil on the Dimensional Stability, moisture absorption, chemical structure, thermoStability, and morphological characteristics of the wood are studied. The results show that Tung oil treatment is an effective technique to improve wood Dimensional Stability. The weight percentage gain was found to attain up to 60.56%, and Tung oil treatment decreased the wood tangential and radial swelling coefficients by 30.8% and 29.6%, respectively. Tung oil treatment also decreased the moisture absorption by 51.53%. Specimens treated with Tung oil presented two sharp peaks of decomposition around 376 °C and 421 °C, while the control specimens exhibited a more common DTG curve with a sharp peak at 376 °C. Tung oil can be impregnated into wood and occluded pits, and solidifies at the internal surface of wood to prevent moisture absorption. This method can be implemented in buildings, furniture, and landscape architecture to broadly expand the application of wood products.
David Bartlett - One of the best experts on this subject based on the ideXlab platform.
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the Dimensional Stability of impression materials and its effect on in vitro tooth wear studies
Dental Materials, 2011Co-Authors: Jose M Rodriguez, David BartlettAbstract:Objectives. To assess the Dimensional Stability of 8 impression materials over 12 weeks relevant to in vitro tribology studies. Methods. Ten impressions from eight impression materials were taken of a metal block (ADA block) conforming to the American Dental Association specification for impression materials and of another metal block (custom block) which allowed measurements over a larger surface area. The impressions and blocks were scanned on a non-contacting laser profilometer (Taicaan ® – Southampton, UK) and using surface metrology software Boddies ® (Taicaan
Carlos Floresmir - One of the best experts on this subject based on the ideXlab platform.
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an in vitro study on the Dimensional Stability of a vinyl polyether silicone impression material over a prolonged storage period
Journal of Prosthetic Dentistry, 2013Co-Authors: Usama Nassar, Marwan Elrich, Samer Adeeb, Carlos FloresmirAbstract:Statement of problem A new elastomeric impression material, a vinyl polyether silicone, has been commercially introduced. Its Dimensional Stability at different pouring times has not been reported. Purpose The purpose of this study was to evaluate the Dimensional Stability of vinyl polyether silicone (VPES) impressions as a function of delayed-pouring time for up to 2 weeks after performing a recommended clinical disinfection procedure. Material and methods The 3 medium-body impression materials tested were EXA'lence 370, Imprint 3, and Impregum Penta soft. Impressions of a cylindrical metal model, which served as a control, were made and poured in a Type V stone after being disinfected in 2.5% buffered glutaraldehyde solution. Die diameter and anteroposterior and cross-arch measurements on each cast were made and compared to direct measurements of the control with a digital micrometer. The linear Dimensional changes were compared and analyzed by using the Mann-Whitney U test (α=.05). Results Considering the absolute values for the mean percentage Dimensional change, VPES cast measurements were below 1.0% ( P Conclusions Casts produced from a disinfected regular set VPES (EXA'lence 370 monophase) demonstrated excellent Dimensional Stability at different pour times and were comparable to the tested VPS and PE impression materials.
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an in vitro study on the Dimensional Stability of a vinyl polyether silicone impression material over a prolonged storage period
Journal of Prosthetic Dentistry, 2013Co-Authors: Usama Nassar, Marwan Elrich, Samer Adeeb, Carlos FloresmirAbstract:Statement of problem A new elastomeric impression material, a vinyl polyether silicone, has been commercially introduced. Its Dimensional Stability at different pouring times has not been reported. Purpose The purpose of this study was to evaluate the Dimensional Stability of vinyl polyether silicone (VPES) impressions as a function of delayed-pouring time for up to 2 weeks after performing a recommended clinical disinfection procedure. Material and methods The 3 medium-body impression materials tested were EXA'lence 370, Imprint 3, and Impregum Penta soft. Impressions of a cylindrical metal model, which served as a control, were made and poured in a Type V stone after being disinfected in 2.5% buffered glutaraldehyde solution. Die diameter and anteroposterior and cross-arch measurements on each cast were made and compared to direct measurements of the control with a digital micrometer. The linear Dimensional changes were compared and analyzed by using the Mann-Whitney U test (α=.05). Results Considering the absolute values for the mean percentage Dimensional change, VPES cast measurements were below 1.0% ( P Conclusions Casts produced from a disinfected regular set VPES (EXA'lence 370 monophase) demonstrated excellent Dimensional Stability at different pour times and were comparable to the tested VPS and PE impression materials.
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Dimensional Stability of irreversible hydrocolloid impression materials as a function of pouring time a systematic review
Journal of Prosthetic Dentistry, 2011Co-Authors: Usama Nassar, Tehnia Aziz, Carlos FloresmirAbstract:Statement of problem Pouring time of irreversible hydrocolloid impressions differs depending on the brand and intended use, either of which may result in variable Dimensional Stability. Purpose The purpose of this study was to investigate the available literature on Dimensional Stability of irreversible hydrocolloid impression materials as a function of pouring time and disinfectant solutions used. Material and methods Three electronic database searches (Medline, PubMed, and EMBASE) were conducted to identify in vitro peer-reviewed studies published in English between the early 1970s and October 2010. Selection criteria included in vitro studies, irreversible hydrocolloid as impression material, and storage time. Heterogeneity in the methodology of the selected studies precluded a meta-analysis. Results Of 62 initially selected studies only 18 were included. Traditional irreversible hydrocolloids were generally stable when poured immediately. However, Stability decreased as time elapsed. New irreversible hydrocolloid substitutes appear to allow delay in pouring time and repouring of impressions without significant side effects. Conclusions Shorter storage time of irreversible hydrocolloid impressions before pouring is desirable, although this may not be necessary for the extended-pour types. The lack of a standardized technique for studying the effect of storage condition, with or without the use of disinfectants, makes it difficult to make clear recommendations.