Abstract: The invention relates to a reducing agent for the soluble chromate content of cement and to methods for the production thereof, which comprise concentrating an used sulfuric acid, containing iron (II) sulfate, and separating the sulfuric acid from the obtained precipitate which contains iron (II) sulfate.

Abstract: In one aspect, a user-wearable illumination assembly 10 includes eyeglass frames 12 and a headlamp 20 removably coupled to the eyeglass frames 12. Electrical circuitry 58 may be integrated with the eyeglass frames 12. The headlamp 20 and the eyeglass frames 12 have mounting structure 22, 26 that cooperate to removably support the headlamp 20 thereon. A light source 36 is disposed within the headlamp 20 and electrical communication between the light source 36 and the electrical circuitry 58 of the eyeglass frames 12 is provided by electrical contacts 40, 42 associated with the mounting structures 22, 26 of the headlamp 20 and eyeglass frames 12. In another aspect, a user-wearable illumination assembly 210 for use with eyeglass frames 212 includes a clip assembly 230 that is selectively removably couplable to a bridge portion 214 of the eyeglass frames 212, and a headlamp 240 coupled to the clip assembly 230.

Abstract: A self-cure or dual-cure polymerizable dental composition is provided with a redox indicator. The composition exhibits an initial first color upon mixing of the two parts and then changes to a second color that is noticeably different from the first color during the curing or polymerization of the composition initiated through the redox initiator system. Advantageously, the first color may be distinctively different from tooth structure and can be easily noticed. The second color may be essentially colorless, a neutral color, or a non-visually observable color in reference to the tooth structure.

Abstract: A dental material is provided that exhibits a color change upon or after mixing or contacting components of the composition. The composition includes an acidic component in one part, and a basic component in another part that upon contact with the acidic component initiates a chemical reaction thereof that alters the pH of the composition. An acid or base sensitive color change agent is present in the composition that registers the change in pH by changing color as the pH changes.

Abstract: A self-cure, dual-cure or tri-cure polymerizable dental composition is provided with at least one functional chemical. The dental composition is divided into a three-part composition to avoid stability issues caused by degradation and/or loss of function of one component in the extended presence of another component, and the three parts are packaged in a tri-barrel syringe or cartridge delivery system to avoid premature chemical interaction between the functional chemical, redox initiator and/or acid/base.

Abstract: A dental restorative composition comprises: (A) polymerizable monomer(s) selected from hydroxyethyl (meth)acrylate phosphate, hydroxypropyl (meth)acrylate phosphate, hydroxybutyl (meth)acrylate phosphate, dipentaerythritol penta(meth)acrylate phosphate, pentaerythritol tri(meth)acrylate phosphate, phenyl (meth)acryloxyethyl phosphate, and a combination thereof; (B) polymerizable monomer(s) having a molecular weight of 100-250, at least one hydroxyl group, and at least one ethylenically unsaturated group; (C) polymerizable monomer(s) having a molecular weight of 270-900, at least two ethylenically unsaturated groups and no acidic functional group; (D) photo-initiator(s); and (E) filler(s) each having a mean particle size of more than 0.005 microns and less than 70 microns. The weight ratio of (A+B):(C) ranges from 30:70 to 90:10, and the composition has a shear bond strength of at least 10MPa to both dentin and enamel after being light-cured.

Abstract: A dental paste dispensing device having a modified dispensing end for atraumatic contact with soft tissue is disclosed. The dispensing device has a metal needle with an attachment end adapted to be attached to a capsule containing the dental paste and a dispensing end with a terminal edge for dispensing the dental paste to a location in a patient mouth containing soft tissue, wherein the dispensing end includes an atraumatic modification. The modification comprises one of a non-metal coating on an outer surface of the dispensing end, a plastic tip member over the dispensing end, or a decreasing diameter at the terminal edge from a first point on the outer surface to a distal-most point of the outer surface.

Abstract: An instrument for curing light-curable compounds that includes at least one light-emitting element operable for emitting light in a band of wavelengths and is capable of curing a light-curable compound. A control circuit controls the operation of the light-emitting element. The control circuit is operable for providing a power signal to the light-emitting element at a steady state power level to drive the element to emit a steady state light output. The control circuit, while continuing with a power signal at the steady state power level, is further operable to provide temporary micro-pulses in the power signal to temporarily provide an increased power level to the light-emitting element above the steady state power level before returning to the steady state power level, to thereby increase the light output of the instrument while controlling heat generated thereby.

Abstract: A dental adhesive composition comprising (i) at least one non-acidic polymerizable monomer having at least one ethylenically unsaturated group, (ii) optionally one or more acidic compounds, (iii) at least one photoinitiator, (iv) at least one solvent, and (v) about 0-40% by weight of one or more fillers; wherein the weight ratio of non-acidic polymerizable monomers/acidic compounds in the adhesive composition is more than about 4.5; the viscosity of the adhesive composition is less than about 350 centipoise (cP) at 25° C.; and the adhesive composition excluding solvent and filler has an acid number of less than about 0.75 mmol NaOH/g. The dental adhesive composition is used with a dental primer composition, which may be provided together in a kit.

Abstract: An apparatus (100) for testing electrical activity from a biological tissue sample comprises a body (1) provided with a well (4), stimulating means (8) for stimulating a sample located in the well (4), and detecting means (9) for detecting electrical activity in the sample. In one embodiment the apparatus has a fluid inlet means (10) and a fluid outlet means (16) in fluid communication with the well (4). The inlet means (10) comprises an electrically conductive conduit (11A) which is in fluid contact with a fluid flowing, in use, though the outlet means (16). In some embodiments the apparatus is provided with an electrically conductive member (19) which is in electrical contact with a fluid contained, in use, in at least one of the well (4), inlet means (10) and outlet means (16). The stimulating means (8) and detecting means (9) are engaged with the body (1) by a gripping means (32) which comprises an electrically conductive gripping member (36). Related methods and apparatus are also disclosed.

Abstract: A dental restorative composition comprises: (A) polymerizable monomer(s) selected from hydroxyethyl (meth)acrylate phosphate, hydroxypropyl (meth)acrylate phosphate, hydroxybutyl (meth)acrylate phosphate, dipentaerythritol penta(meth)acrylate phosphate, pentaerythritol tri(meth)acrylate phosphate, phenyl (meth)acryloxyethyl phosphate, and a combination thereof; (B) polymerizable monomer(s) having a molecular weight of 100-250, at least one hydroxyl group, and at least one ethylenically unsaturated group; (C) polymerizable monomer(s) having a molecular weight of 270-900, at least two ethylenically unsaturated groups and no acidic functional group; (D) photo-initiator(s); and (E) filler(s) each having a mean particle size of more than 0.005 microns and less than 70 microns. The weight ratio of (A+B):(C) ranges from 30:70 to 90:10, and the composition has a shear bond strength of at least 10 MPa to both dentin and enamel after being light-cured.

Abstract: A one-component self-etching self-priming dental adhesive composition is disclosed. The composition comprises glycerol phosphate di(meth)acrylate monomer, at least one mono-functional polymerizable monomer having just one ethylenically unsaturated group, at least one multi-functional polymerizable monomer having at least two ethylenically unsaturated groups, at least one aprotic solvent, at least one protic solvent, and at least one polymerization initiator.

Abstract: A dental adhesive composition comprising (i) at least one non-acidic polymerizable monomer having at least one ethylenically unsaturated group, (ii) optionally one or more acidic compounds, (iii) at least one photoinitiator, (iv) at least one solvent, and (v) about 0-40% by weight of one or more fillers; wherein the weight ratio of non-acidic polymerizable monomers/acidic compounds in the adhesive composition is more than about 4.5; the viscosity of the adhesive composition is less than about 350 centipoise (cP) at 25° C.; and the adhesive composition excluding solvent and filler has an acid number of less than about 0.75 mmol NaOH/g. The dental adhesive composition is used with a dental primer composition, which may be provided together in a kit.

Abstract: A dental restorative composition comprising: (A) polymerizable monomer(s) having at least one phosphorus-containing acidic moiety and at least one ethylenically unsaturated group; (B) polymerizable monomer(s) having a molecular weight of 100-250, at least one hydroxyl group, and at least one ethylenically unsaturated group; (C) polymerizable monomer(s) having a molecular weight of 270-900, at least two ethylenically unsaturated groups and no acidic functional group; (D) photo-initiator(s); and (E) filler(s) each having a mean particle size of more than 0.005 microns and less than 70 microns. The weight ratio of (A+B):(C) ranges from 30:70 to 90:10, the concentration of (A) is 10-50 wt. %, the concentration of (B) is 15-60 wt. %, and the composition has a shear bond strength of at least 10 MPa to both dentin and enamel. Also provided is a method for filling a dental cavity with the composition without first treating the dental cavity with an etchant, a primer and/or an adhesive.

Abstract: A one-component self-etching self-priming dental adhesive composition is disclosed. The composition comprises glycerol phosphate di(meth)acrylate monomer, at least one mono-functional polymerizable monomer having just one ethylenically unsaturated group, at least one multi-functional polymerizable monomer having at least two ethylenically unsaturated groups, at least one aprotic solvent, at least one protic solvent, and at least one polymerization initiator.

Abstract: A method for temporarily widening a gingival sulcus is provided using an uncured composition comprising a polymerizable monomer having at least one ethylenically unsaturated group, a photo polymerization initiator, a fine inorganic powder, and an astringent. The uncured composition is inserted within a gingival sulcus to be widened, and the composition is thereafter irradiated in situ to polymerize the composition. The result is a rubbery material that is easily removable from the widened sulcus.

Abstract: A one-component self-etching self-priming dental adhesive composition is disclosed. The composition comprises glycerol phosphate di(meth)acrylate monomer, at least one mono-functional polymerizable monomer having just one ethylenically unsaturated group, at least one multi-functional polymerizable monomer having at least two ethylenically unsaturated groups, at least one aprotic solvent, at least one protic solvent, and at least one polymerization initiator.

Abstract: A composition curable by a metathesis reaction upon mixing its components and comprising an olefin-containing substrate, a metathesis catalyst, and a reaction control agent for slowing the progress of the metathesis reaction. The metathesis catalyst is a ruthenium or osmium carbene complex catalyst having high activity and good air stability. In one embodiment, the catalyst is free of phosphine ligands. The reaction control agent is an organic compound that contains carbon-carbon double and/or triple bonds and one or more Group 14 atoms and is present in an amount effective to slow the progress of the metathesis reaction. In one embodiment, the olefin-containing substrate may comprise one or more oligomers or polymers having a >20 wt. % linear siloxane (Si—O—Si) backbone tethered and/or end-capped with functional olefin groups, such as cycloalkenyl group.

Abstract: An optical loupe includes a housing, an eyepiece lens supported in the housing, and an objective lens supported in the housing. The optical loupe further includes a filter lens supported in the housing and adapted to prevent the transmission of electromagnetic radiation of at least a predetermined wavelength. In another embodiment, a user-wearable optical system includes a user-wearable device and an optical loupe having an objective lens, an eyepiece lens, and a filter lens supported in a housing. The filter lens is adapted to prevent the transmission of electromagnetic radiation of at least a predetermined wavelength.

Abstract: A dental restorative composition comprising: (A) polymerizable monomer(s) having at least one phosphorus-containing acidic moiety and at least one ethylenically unsaturated group; (B) polymerizable monomer(s) having a molecular weight of 100-250, at least one hydroxyl group, and at least one ethylenically unsaturated group; (C) polymerizable monomer(s) having a molecular weight of 270-900, at least two ethylenically unsaturated groups and no acidic functional group; (D) photo-initiator(s); and (E) filler(s) each having a mean particle size of more than 0.005 microns and less than 70 microns. The weight ratio of (A+B):(C) ranges from 30:70 to 90:10, the concentration of (A) is 10-50 wt. %, the concentration of (B) is 15-60 wt. %, and the composition has a shear bond strength of at least 10 MPa to both dentin and enamel. Also provided is a method for filling a dental cavity with the composition without first treating the dental cavity with an etchant, a primer and/or an adhesive.