Den-mat Corporation

The Gillette Company

Thomas C Chadwick

Robert L Ibsen

Rachel R Pineda

Heather L Hunt

Alan B Matthews

Xinyi Yu

David F Ouellet

Ron DeMoss

Alan Mathews

Rebecca K Santiago

Sally A Pritchard

A family of radiopaque glasses comprising silicon dioxide (15&#x2013;30%), ytterbium oxide (5&#x2013;35%), barium oxide (30&#x2013;50%) and fluoride (5&#x2013;20%), all by weight. The family of glasses all exhibit high radiopacity with refractive indices varying from 1.508&#x2013;1.592 and translucency ranging from clear to moderately opaque. These glasses can be incorporated into dental composites to provide radiopaque dental restoratives with a desired translucence and appearance.

Ytterbium-barium silicate radiopaque glasses

An aqueous gel useful for bleaching teeth comprising: (i) water; (ii) polyacrylic acid thickening agent; (iii) hydrogen peroxide bleaching agent; and (iv) aminocarboxylic acid/salt stabilizing agent. Preferably the polyacrylic acid is an easy to disperse carbomer and the gels contain high concentrations (20 to 40% by weight) of hydrogen peroxide. The gels exhibit room temperature stability, both with respect to gel stability and hydrogen peroxide decomposition, sufficient to eliminate the need for constant refrigeration. A method for using the gels to bleach teeth is also disclosed.

Stable tooth whitening gels containing high percentages of hydrogen peroxide

Methods for making molding casts by a process typically referred to as &ldquo;investment casting&rdquo; using a novel composition is described. The composition is a phosphate bonded material that contains mono-ammonium phosphate (MAP), magnesium oxide and silica filler (quartz, cristobalite, or a mixture thereof). It has been discovered that controlling the amount and ratio of these components has a significant impact on gas permeability (porosity), set time, cast smoothness and cast softness. The most outstanding feature of the new investments is the short mold fabrication and processing time that they allow due to their high gas permeability. The investments can be placed in a burn out furnace while still wet and can be heated rapidly to the firing temperature. The casts can be broken by sandblasting the casts with glass beads. Molds made from the casts have smooth surfaces indicating that the casts are free of visible inclusions and other defects.

Phosphate investment compositions and methods of use thereof

An investment composition is described for use in investment casting (also called lost wax casting). The composition is a phosphate bonded material that contains mono-ammonium phosphate (MAP), magnesium oxide and silica filler (quartz, cristobalite, or a mixture thereof). It has been discovered that controlling the amount and ratio of these components has a significant impact on gas permeability (porosity), set time, cast smoothness and cast softness. The most outstanding feature of the new investments is the short mold fabrication and processing time that they allow due to their high gas permeability. The investments can be placed in a bum out furnace while still wet and can be heated rapidly to the firing temperature. The casts can be broken by sandblasting the casts with glass beads. Molds made from the casts have smooth surfaces indicating that the casts are free of visible inclusions and other defects.

Phosphate investment compositions

The instant invention relates to an anhydrous dentifrice (toothpaste, brushing gel, etc . . . ) The dentifrice is a homogeneous mixture of the following compounds: (1) organic polyols, such as glycerin; (2) cooked starch gelling agents; (3) mildly abrasive fillers such as silica, alumina and dicalcium phosphate; and, optionally, (4) compounds selected from the group consisting of anti-caries agents, anti-plaque agents, anti-calculus agents, bleaching agents, peroxide stabilizers, desensitizing agents, whiteners, anti-stain agents, breath fresheners, flavorants, sweeteners, colorants, buffers, surfactants, and anti-bacterial agents, with the proviso that if bleaching agents are employed then peroxide stabilizers must also be employed. Preferably, the dentifrice does not contain any gelling agent other than the cooked starch particles.

Starch thickened non-aqueous dentifrices

A substantially anhydrous gel useful for bleaching teeth comprising: (i) at least 25% by weight of organic polyol; (ii) less than 3% by weight polyacrylic acid thickening agent; (iii) at least 10% by weight carbamide peroxide (or a chemically equivalent amount of another bleaching agent, such as 3% by weight hydrogen peroxide); (iv) neutralizing agent; (v) chelating agents; (vi) desensitizing agent; and (vii) miscellaneous ingredients such as Cirtoxain&reg; and flavorants. The organic polyol is preferably glycerin. The polyacrylic acid thickening agent is preferably a carbomer. The desensitizing agent is preferably potassium nitrate, strontium chloride, potassium citrate, strontium nitrate, or a similarly effective alkali or alkaline earth metal salt of an organic or inorganic acid.

Desensitizing bleaching gel

Shaped article replicas which are proportionately accurate replicas of a shaped article and which are equal, greater or smaller in size than said shaped article are made by preparing a swellable polymer replica of said shaped article; immersing said swellable polymer replica in a swelling agent system under conditions which will enlarge said polymer replica to a predetermined extent; forming a casting mold of such enlarged polymer replica; making a powder compact in said casting mold and heating said powder compact to produced a proportionately accurate solid replica of a predetermined size.

Method for accurate replication of shaped articles using sinterable

Shaped article replicas which are proportionately accurate replicas of a shaped article and which are equal, greater or smaller in size than said shaped article are made by preparing a swellable polymer cavity mold from said shaped article; immersing said swellable polymer cavity mold in a swelling agent system under conditions which will enlarge said cavity mold to a predetermined extent; forming a powder compact in said casting mold or a replica thereof and heating said powder compact to produced a proportionately accurate solid replica of a predetermined size.

Shaped articles such as dental onlays and inlays having at least one surface adapted to mate with a mating surface of a second shaped article are produced by a procedure which includes immersing a swellable polymer casting mold in a swelling agent system to swell such casting mold to an extent which compensates for the shrinkage which occurs when a sinterable powder compact made therein or in a solid replica thereof, is heated.

A method and apparatus for heat-curing light-cured resins by means of placing the resin in an oven attachment coupled to a high intensity light source, such that heat generated by the light source raises the temperature within the oven attachment to at least 140.degree. C., and maintains the temperature above 140.degree. C. for at least 10 minutes. The oven attachment has a body fabricated from a rigid material having a relatively low thermal conductivity. The oven attachment is fashioned to fit over the light outlet of a conventional light source. The oven attachment is preferably held in place by the same mechanism that holds a light-curing 'wand' to the light source. The light source is turned on for a heating period of approximately 15 minutes, causing the temperature within an oven chamber within the oven attachment to rise. Upon completion of the heating period, the light source is turned off and the heat-cured restoration may be removed.

Method and apparatus for heat curing resin compounds

A glass composition, containing barium oxide, which provides a source of leachable fluoride and which can be incorporated into a dental cement composition which, when cured, is radiopaque and translucent.

Fluoride ion-leachable glasses and dental cement compositions containing

A dental porcelain having the following composition:

Growing community of inventors

Nipomo, CA, United States of America

Thomas C Chadwick