The Experts below are selected from a list of 124713 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.
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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, 2014Co-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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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, 2014Co-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.
Lei Zhang - One of the best experts on this subject based on the ideXlab platform.
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3d Surface Detail enhancement from a single normal map
International Conference on Computer Vision, 2017Co-Authors: Wuyuan Xie, Miaohui Wang, Lei ZhangAbstract:In 3D reconstruction, the obtained Surface Details are mainly limited to the visual sensor due to sampling and quantization in the digitalization process. How to get a fine-grained 3D Surface with low-cost is still a challenging obstacle in terms of experience, equipment and easyto-obtain. This work introduces a novel framework for enhancing Surfaces reconstructed from normal map, where the assumptions on hardware (e.g., photometric stereo setup) and reflection model (e.g., Lambertion reflection) are not necessarily needed. We propose to use a new measure, angle profile, to infer the hidden micro-structure from existing Surfaces. In addition, the inferred results are further improved in the domain of discrete geometry processing (DGP) which is able to achieve a stable Surface structure under a selectable enhancement setting. Extensive simulation results show that the proposed method obtains significantly improvements over uniform sharpening method in terms of both subjective visual assessment and objective quality metric.
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ICCV - 3D Surface Detail Enhancement from a Single Normal Map
2017 IEEE International Conference on Computer Vision (ICCV), 2017Co-Authors: Wuyuan Xie, Miaohui Wang, Lei ZhangAbstract:In 3D reconstruction, the obtained Surface Details are mainly limited to the visual sensor due to sampling and quantization in the digitalization process. How to get a fine-grained 3D Surface with low-cost is still a challenging obstacle in terms of experience, equipment and easyto-obtain. This work introduces a novel framework for enhancing Surfaces reconstructed from normal map, where the assumptions on hardware (e.g., photometric stereo setup) and reflection model (e.g., Lambertion reflection) are not necessarily needed. We propose to use a new measure, angle profile, to infer the hidden micro-structure from existing Surfaces. In addition, the inferred results are further improved in the domain of discrete geometry processing (DGP) which is able to achieve a stable Surface structure under a selectable enhancement setting. Extensive simulation results show that the proposed method obtains significantly improvements over uniform sharpening method in terms of both subjective visual assessment and objective quality metric.
Serhat Emre Ozkir - One of the best experts on this subject based on the ideXlab platform.
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The influence of different mixing methods on the dimensional stability and Surface Detail reproduction of two different brands of irreversible hydrocolloids
European Journal of General Dentistry, 2014Co-Authors: Ahmetkursad Culhaoglu, Evrim Dogan, Ali Zaimoglu, Serhat Emre OzkirAbstract:Purpose: Irreversible hydrocolloid impression materials are some of the most common impression materials in dentistry. Preparation of alginate is critical for dental appliance fabricated upon the cast made directly from the impression. This study compared the effect of two mixing methods i.e. hand mixing or device mixing on the physical properties of two different brands of irreversible hydrocolloid. Materials and Methods: Two alginate impression materials: Cavex Tulip (Tulip, Cavex Holland BV, Haarlem, Holland) and Hydrogum Soft (Zhermack, Rovigo, Italy), were mixed according to manufacturers instroductions with two mixing methods. Mixing was performed at room temperature using tap water. The material was allowed to set in a water bath at 35°C (±1°C), simulating intra‑oral setting conditions. For each tested material, nine standardized samples were used. The first method was hand mixing; the other method was with a device. Detail reproduction and dimensional changes of impressions were compared. One‑way analysis of variance was performed to compare the dimensional differences between the four groups. Results: The device mixed speciemens showed better Surface Detail than hand‑mixed samples. Cavex alginate demonstrated better Surface Detail than Hydrogum. Cavex Tulip alginate showed better dimensional stability than Hydrogum Soft in both hand‑mixed and device‑mixed samples. Furthermore, all device mixed samples were better than hand‑mixed in terms of dimensional stability. A two‑way analysis of variance and Fisher's protected least significant difference test at the 0.05 level of significance were used to analyze the data. Conclusion: Of the two mixing methods, the vacuum mixer had the best performance overall in reducing the number, percent and volume of porosities in the mixed alginate.
Dr Moles - One of the best experts on this subject based on the ideXlab platform.
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Effect of immersion disinfection with Perform-ID on alginate, an alginate alternative, an addition-cured silicone and resultant type III gypsum casts
British Dental Journal, 2007Co-Authors: S. Ahmad, Christopher Tredwin, Michael Nesbit, Dr MolesAbstract:Objective This study investigated the effect of a commonly used immersion disinfectant upon three different impression materials and any subsequent effects on the abrasion resistance, hardness and Surface Detail reproduction of gypsum casts. Design A laboratory study. Materials and methods Under standardised conditions a total of 120 impressions were made of a ruled test block using irreversible hydrocolloid (Alginoplast), an 'alginate alternative' addition-cure silicone (Position Penta) and a conventional addition-cure silicone (President). The impressions were examined for Surface Detail reproduction prior to and after disinfection with Perform-ID. The type III casts were evaluated for Surface Detail reproduction, Surface hardness and abrasion resistance. Results (1) None of the disinfected alginate specimens could reproduce the 50 μm line. (2) Casts produced from the disinfected alginate were significantly less hard than from disinfected Position Penta and President (P 0.05). Conclusion If disinfecting with Perform-ID, the impression should be made with a conventional addition-cured silicone if good Surface Detail reproduction of the impression material and a hard and abrasion resistant type III gypsum cast are required. Allows dental practitioners to recognise that immersion disinfection may have detrimental effects on the impression materials and gypsum casts poured from them. Details what categories of impression materials may be subject to these problems with immersion disinfection. Provides a working solution to the problem.
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Effect of immersion disinfection with Perform-ID on alginate, an alginate alternative, an addition-cured silicone and resultant type III gypsum casts.
British Dental Journal, 2007Co-Authors: S. Ahmad, Christopher Tredwin, Michael Nesbit, Dr MolesAbstract:Objective This study investigated the effect of a commonly used immersion disinfectant upon three different impression materials and any subsequent effects on the abrasion resistance, hardness and Surface Detail reproduction of gypsum casts. Design A laboratory study. Materials and methods Under standardised conditions a total of 120 impressions were made of a ruled test block using irreversible hydrocolloid (Alginoplast), an 'alginate alternative' addition-cure silicone (Position Penta) and a conventional addition-cure silicone (President). The impressions were examined for Surface Detail reproduction prior to and after disinfection with Perform-ID. The type III casts were evaluated for Surface Detail reproduction, Surface hardness and abrasion resistance. Results (1) None of the disinfected alginate specimens could reproduce the 50 μm line. (2) Casts produced from the disinfected alginate were significantly less hard than from disinfected Position Penta and President (P 0.05). Conclusion If disinfecting with Perform-ID, the impression should be made with a conventional addition-cured silicone if good Surface Detail reproduction of the impression material and a hard and abrasion resistant type III gypsum cast are required.
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The effect of disinfection on irreversible hydrocolloid and type III gypsum casts.
Eur J Prosthodont Restor Dent, 2006Co-Authors: Dr MolesAbstract:Under standardised conditions, 80 impressions were made of a ruled stainless steel die (ISO Specification 1563) using irreversible hydrocolloid (alginate). The alginates were subsequently treated with 3 commercially available disinfectants, Perform-ID, ImpressiVand Dimenol and poured with type III gypsum. The alginates were evaluated for Surface Detail reproduction and the gypsum for Surface Detail reproduction and hardness. Disinfection with Perform ID significantly affected the Surface Detail reproduction of alginate while Dimenol and ImpressiV did not. Perform ID and Dimenol both significantly affect the hardness of poured type III gypsum casts while ImpressiV did not.