The Experts below are selected from a list of 318 Experts worldwide ranked by ideXlab platform
Jukka Pekka Matinlinna - One of the best experts on this subject based on the ideXlab platform.
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silane adhesion mechanism in dental applications and surface treatments a review
Dental Materials, 2018Co-Authors: Jukka Pekka Matinlinna, Christie Ying Kei Lung, James Kit Hon TsoiAbstract:Abstract Objective To give a current review of silane adhesion chemistry, applications of silane coupling agents and related surface pretreatment methods in contemporary dentistry. Methods Silane coupling agents are adhesion promoters to chemically unify dissimilar materials used in dentistry. Silanes are very effective in adhesion promotion between resin composites and silica-based or silica-coated indirect restorative materials. It is generally accepted that for non-silica-based restorations, surface pretreatment is a mandatory preliminary step to increase the silica content and then, with help of silane, improve resin bonding. This review discusses the silane-based adhesion chemistry, silane applications in dentistry, surface pretreatment methods, and presents the recent development of silane coupling agents. Results A silane coupling agent is considered a reliable, good adhesion promoter to silica-based (or silica-coated) indirect restorations. Surface pre-treatment steps, e.g., acid etching for porcelain and tribo-chemical silica-coating for metal alloys, is used before silanization to attain strong, durable bonding of the substrate to resin composite. In clinical practice, however, the main problem of resin bonding using Silanes and other coupling agents is the weakening of the bond (degradation) in the wet oral environment over time. Significance A silane coupling agent is a justified and popular adhesion promoter (adhesive primer) used in dentistry. The commercial available silane coupling agents can fulfil the requirements in clinical practice for durable bonding. Development of new silane coupling agents, their optimization, and surface treatment methods are in progress to address the long term resin bond durability and are highly important.
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aspects of silane coupling agents and surface conditioning in dentistry an overview
Dental Materials, 2012Co-Authors: Christie Ying Kei Lung, Jukka Pekka MatinlinnaAbstract:Abstract Objectives To give an overview of aspects of silane coupling agents and surface conditioning in dentistry. Methods Currently, silane coupling agents are used as adhesion promoters. Silanes are effective in enhancing adhesion between resin composite and silica-based ceramics. They do not bond effectively to non-silica based dental restorative materials. Surface conditioning of non-silica based ceramics with silica coating improves the bonding. This current overview will focus on the silane coupling agents: their properties, limitations in adhesion promotion and the clinical problems with the use of Silanes. It will also focus on the current surface conditioning methods as well as new surface conditioning techniques to enhance the bonding through conventional silanization approaches. Results Several surface conditioning methods are being used clinically to enhance the adhesion of resin composites to non-silica based restorative materials. Other approaches are under investigation. The clinical problem of using Silanes in adhesion promotion is the bond degradation over time in oral environment. Significance The current silane coupling agents are not ideal. The current silane coupling agents can fulfill the minimum requirements in clinical practice to enhance the bonding of resin composite to dental restorative materials. Developments of novel surface conditioning methods and silane coupling agents are required to address the bond durability problem.
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evaluation of five dental Silanes on bonding a luting cement onto silica coated titanium
Journal of Dentistry, 2006Co-Authors: Jukka Pekka Matinlinna, Lippo V J Lassila, Pekka K VallittuAbstract:Abstract Objectives Five commercial dental Silanes were evaluated in vitro as adhesion promoters bonding a luting cement to silica-coated titanium surfaces . Methods Titanium slides ( n = 20) were cleaned with alumina sand and then silica-coated with a special sand consisting of alumina particles coated with silica. The bonding of a resin composite cement (3 M ESPE, Seefeld, Germany) to silica-coated and silanized titanium was evaluated by using the dental silane (RelyX™ Ceramic Primer) that belongs to the RelyX™ ARC cementing kit, and comparing it to four other dental Silanes (Bisco Porcelain Primer™, Cimara™, ESPE Sil™, and Pulpdent™ Silane Bond Enhancer). The resin composite cement stubs ( n = 8) were light-polymerized onto a silanized silica-coated titanium surface. The shear bond strength of the cement stubs was measured after dry storage and thermo-cycling 6000 times between 5 and 55 °C. The Silanes and their reactions were chemically monitored by using Fourier transform infrared analysis. Results Statistical analysis using ANOVA revealed that the brand of Silanes and the types of storage condition differ significantly ( p Conclusions Dental Silanes provide different bonding strengths and have differences in their pH, solvent system and silane concentration.
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an introduction to Silanes and their clinical applications in dentistry
International Journal of Prosthodontics, 2004Co-Authors: Jukka Pekka Matinlinna, Lippo V J Lassila, Mutlu Ozcan, Antti Yliurpo, Pekka K VallittuAbstract:Purpose: This overview presents a description of organofunctional trialkoxysilane coupling agents (Silanes), their chemistry, properties, use, and some of the main clinical experiences in dentistry. Materials and Methods: The main emphasis was on major dental journals that have been reviewed from 1958 up to the latest research news from 2002. A MEDLINE search with the key words “dental Silanes” was used. Special silane literature and journals outside dentistry were also cited. Results: The main emphasis is on the use of Silanes in prosthetic and restorative dentistry. Clinical relevance was based mainly on either short- or long-term tests. The interpretation of various results is not given, mainly because of controversial observations that may be very difficult to explain. Nevertheless, the majority of the clinical results pointed to Silanes playing a significant role in the adhesion process. Silane reaction mechanisms were not entirely understood, and there exist several theories for bonding mechanisms for Silanes and substrates. Conclusion: Dental materials offer a continuously challenging forum for Silanes, and Silanes will play an essential role in material development. Publ. in: Int J Prosthodont 2004;17:155–164.
Sukbok Chang - One of the best experts on this subject based on the ideXlab platform.
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Borane catalysed ring opening and closing cascades of furans leading to silicon functionalized synthetic intermediates
Nature Communications, 2016Co-Authors: Chinmoy K. Hazra, Narasimhulu Gandhamsetty, Sehoon Park, Sukbok ChangAbstract:The conversion of renewable biomass resources to synthetically valuable chemicals is highly desirable, but remains a formidable challenge in regards to the substrate scope and reaction conditions. Here we present the development of tris(pentafluorophenyl)borane–catalysed conversion of furans via ring-opening and closing cascade processes to afford silicon-functionalized synthetic chemicals under transition metal-free conditions. The furan ring-opening with hydroSilanes is highly efficient (TON up to 2,000) and atom-economical without forming any byproduct to give rise to α-silyloxy-( Z )-alkenyl Silanes. Additional equivalents of silane smoothly induce a subsequent B(C_6F_5)_3-catalysed cyclization of initially formed olefinic silane compounds to produce anti -(2-alkyl)cyclopropyl Silanes, another versatile synthon being potentially applicable in the synthesis of natural products and pharmacophores. Furans are attractive staring materials in organic chemistry, due to the ease of functionalisation and sourcing from renewable feedstocks. Here the authors show the ring opening of furans to silane intermediates, followed by further conversion to cyclopropanes and other high value targets.
Christie Ying Kei Lung - One of the best experts on this subject based on the ideXlab platform.
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silane adhesion mechanism in dental applications and surface treatments a review
Dental Materials, 2018Co-Authors: Jukka Pekka Matinlinna, Christie Ying Kei Lung, James Kit Hon TsoiAbstract:Abstract Objective To give a current review of silane adhesion chemistry, applications of silane coupling agents and related surface pretreatment methods in contemporary dentistry. Methods Silane coupling agents are adhesion promoters to chemically unify dissimilar materials used in dentistry. Silanes are very effective in adhesion promotion between resin composites and silica-based or silica-coated indirect restorative materials. It is generally accepted that for non-silica-based restorations, surface pretreatment is a mandatory preliminary step to increase the silica content and then, with help of silane, improve resin bonding. This review discusses the silane-based adhesion chemistry, silane applications in dentistry, surface pretreatment methods, and presents the recent development of silane coupling agents. Results A silane coupling agent is considered a reliable, good adhesion promoter to silica-based (or silica-coated) indirect restorations. Surface pre-treatment steps, e.g., acid etching for porcelain and tribo-chemical silica-coating for metal alloys, is used before silanization to attain strong, durable bonding of the substrate to resin composite. In clinical practice, however, the main problem of resin bonding using Silanes and other coupling agents is the weakening of the bond (degradation) in the wet oral environment over time. Significance A silane coupling agent is a justified and popular adhesion promoter (adhesive primer) used in dentistry. The commercial available silane coupling agents can fulfil the requirements in clinical practice for durable bonding. Development of new silane coupling agents, their optimization, and surface treatment methods are in progress to address the long term resin bond durability and are highly important.
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aspects of silane coupling agents and surface conditioning in dentistry an overview
Dental Materials, 2012Co-Authors: Christie Ying Kei Lung, Jukka Pekka MatinlinnaAbstract:Abstract Objectives To give an overview of aspects of silane coupling agents and surface conditioning in dentistry. Methods Currently, silane coupling agents are used as adhesion promoters. Silanes are effective in enhancing adhesion between resin composite and silica-based ceramics. They do not bond effectively to non-silica based dental restorative materials. Surface conditioning of non-silica based ceramics with silica coating improves the bonding. This current overview will focus on the silane coupling agents: their properties, limitations in adhesion promotion and the clinical problems with the use of Silanes. It will also focus on the current surface conditioning methods as well as new surface conditioning techniques to enhance the bonding through conventional silanization approaches. Results Several surface conditioning methods are being used clinically to enhance the adhesion of resin composites to non-silica based restorative materials. Other approaches are under investigation. The clinical problem of using Silanes in adhesion promotion is the bond degradation over time in oral environment. Significance The current silane coupling agents are not ideal. The current silane coupling agents can fulfill the minimum requirements in clinical practice to enhance the bonding of resin composite to dental restorative materials. Developments of novel surface conditioning methods and silane coupling agents are required to address the bond durability problem.
James Kit Hon Tsoi - One of the best experts on this subject based on the ideXlab platform.
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silane adhesion mechanism in dental applications and surface treatments a review
Dental Materials, 2018Co-Authors: Jukka Pekka Matinlinna, Christie Ying Kei Lung, James Kit Hon TsoiAbstract:Abstract Objective To give a current review of silane adhesion chemistry, applications of silane coupling agents and related surface pretreatment methods in contemporary dentistry. Methods Silane coupling agents are adhesion promoters to chemically unify dissimilar materials used in dentistry. Silanes are very effective in adhesion promotion between resin composites and silica-based or silica-coated indirect restorative materials. It is generally accepted that for non-silica-based restorations, surface pretreatment is a mandatory preliminary step to increase the silica content and then, with help of silane, improve resin bonding. This review discusses the silane-based adhesion chemistry, silane applications in dentistry, surface pretreatment methods, and presents the recent development of silane coupling agents. Results A silane coupling agent is considered a reliable, good adhesion promoter to silica-based (or silica-coated) indirect restorations. Surface pre-treatment steps, e.g., acid etching for porcelain and tribo-chemical silica-coating for metal alloys, is used before silanization to attain strong, durable bonding of the substrate to resin composite. In clinical practice, however, the main problem of resin bonding using Silanes and other coupling agents is the weakening of the bond (degradation) in the wet oral environment over time. Significance A silane coupling agent is a justified and popular adhesion promoter (adhesive primer) used in dentistry. The commercial available silane coupling agents can fulfil the requirements in clinical practice for durable bonding. Development of new silane coupling agents, their optimization, and surface treatment methods are in progress to address the long term resin bond durability and are highly important.
Chinmoy K. Hazra - One of the best experts on this subject based on the ideXlab platform.
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Borane catalysed ring opening and closing cascades of furans leading to silicon functionalized synthetic intermediates
Nature Communications, 2016Co-Authors: Chinmoy K. Hazra, Narasimhulu Gandhamsetty, Sehoon Park, Sukbok ChangAbstract:The conversion of renewable biomass resources to synthetically valuable chemicals is highly desirable, but remains a formidable challenge in regards to the substrate scope and reaction conditions. Here we present the development of tris(pentafluorophenyl)borane–catalysed conversion of furans via ring-opening and closing cascade processes to afford silicon-functionalized synthetic chemicals under transition metal-free conditions. The furan ring-opening with hydroSilanes is highly efficient (TON up to 2,000) and atom-economical without forming any byproduct to give rise to α-silyloxy-( Z )-alkenyl Silanes. Additional equivalents of silane smoothly induce a subsequent B(C_6F_5)_3-catalysed cyclization of initially formed olefinic silane compounds to produce anti -(2-alkyl)cyclopropyl Silanes, another versatile synthon being potentially applicable in the synthesis of natural products and pharmacophores. Furans are attractive staring materials in organic chemistry, due to the ease of functionalisation and sourcing from renewable feedstocks. Here the authors show the ring opening of furans to silane intermediates, followed by further conversion to cyclopropanes and other high value targets.
