sodium-hypochlorite and methylethyl-ketone

A practical synthesis of 3-methylnonane-2,4-dione, which is an intense strawlike and fruity flavored compound, has been performed by the aldol condensation of n-hexanal and methyl ethyl ketone, followed by oxidation using sodium hypochlorite in the presence of 4-benzoyloxy-2,2,6,6-tetramethylpiperidine-N-oxide in an overall yield of 59%. The purification of 3-methylnonane-2,4-dione with high purity was performed via copper complexes.

Topics: Aldehydes; Alkanes; Butanones; Copper; Flavoring Agents; Ketones; Odorants; Oxidation-Reduction; Sodium Hypochlorite; Soybean Oil; Taste

This study compared the capability of three composite resin cements to sustain a standard endodontic dowel. All of the systems incorporated some form of smear layer removal on the dentin of the endodontic channel. One system that used a methyl ethyl ketone drying agent provided inadequate clinical resistance to dislodgment of 5.4 DaN. A second cementing system that used only smear layer removal resisted loads at 54.7 DaN. The third cementing regimen that included a surface-initiated dentinal adhesive and smear layer removal recorded retention of 77.4 DaN. This study supported the concept that passively cemented dowels with composite resin can be as effective as actively seated dowels.

Topics: Acrylic Resins; Bisphenol A-Glycidyl Methacrylate; Boron Compounds; Butanones; Cementation; Chlorides; Citrates; Citric Acid; Composite Resins; Dental Bonding; Dental Cements; Dental Implantation, Endosseous, Endodontic; Edetic Acid; Ferric Compounds; Humans; Methacrylates; Methylmethacrylates; Polyethylene Glycols; Polymethacrylic Acids; Prosthesis Failure; Root Canal Irrigants; Root Canal Therapy; Smear Layer; Sodium Hypochlorite; Stress, Mechanical