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dc.contributor.authorFadavi, Farnazen_US
dc.date.accessioned2019-12-10T14:09:47Z
dc.date.available2019-12-10T14:09:47Z
dc.date.issued2002
dc.date.submitted2002
dc.identifier.other(OCoLC)52906154
dc.identifier.otherb24813461
dc.identifier.urihttps://hdl.handle.net/2144/38711
dc.descriptionThesis(M.S.D.)--Boston University, Henry M. Goldman School of Dental Medicine, 2002 (Endodontics).en_US
dc.descriptionIncludes bibliographical references (leaves 70-72).en_US
dc.description.abstractCurrent dentin bonding formulations depend on the infusion of low viscosity monomers into demineralized dentin to form the so-called “hybrid layer". It has been suggested that hybrid layer durability can be improved by adding filler particles to the monomers, but the requirement for low viscosity limits the filler volume fraction, and hence, mechanical properties. Furthermore, the inter-collagen fiber spacing ([less than]20 nm) limits both particle size and particle distribution. The purpose of this study is to simultaneously address these challenges by infusing the inter-collagen space with a mixture of organic monomers and inorganic precursors, which would react and nucleate filler particles in situ, after uniform infusion and distribution. The objective of this study is to investigate the feasibility and identify the relevant parameters, which govern this in situ nucleation approach. Organic monomers were mixed with silica precursor TMOS (tetramethyl orthosilicates), methanol, and water. The formation of silica bond during the reaction was verified and confirmed both by scanning electron microscopy (SEM), and Fourier transform infra-red spectroscopy. The relative influence of acid content, monomer reactivity, TMOS contents, and water: alcohol ratio on mechanical properties were evaluated by macrohardness and shear bond testing. Formation of resin tags were confirmed by SEM. Formation of nanoparticles (silica) was observed by EDX for TMOS modified monomers in comparison with non-modified monomers (P&B NT). No significant difference was found between the dentin shear bond strength of the experimental formulation (addition of nanoparticles to P&B NT) and a commercially available nano-filled bonding system (P&B NT) (ANOVA, P[greater than]0.05). Conversely, while dentin pull-out failure was observed for specimens bonded with the commercial system (P&B NT), composite failure was observed for specimens bonded with the experimental system (TMOS-modified monomers).en_US
dc.language.isoen_US
dc.publisherBoston Universityen_US
dc.rightsThis work is being made available in OpenBU by permission of its author, and is available for research purposes only. All rights are reserved to the author.en_US
dc.subjectResin cementsen_US
dc.titleAssessing the feasibility of improving resin adhesive performance by incorporating tetramethyl orthosilicates (TMOS)en_US
dc.typeThesis/Dissertationen_US
etd.degree.nameMaster of Science in Dentistryen_US
etd.degree.levelmastersen_US
etd.degree.disciplineEndodonticsen_US
etd.degree.grantorBoston Universityen_US


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