Abstract: A single-piece, injection molded rack for holding test tubes or similar articles and a mold for producing the same. In a preferred three-tiered form, the intermediate tier is a lattice defined by the intersection of two superposed sets of parallel bars. These two sets of bars are formed by two pairs of correspondingly channeled slides that cooperatively engage to form a portion of the mold cavity corresponding to the lattice. The channels in each set of slides are aligned with the path of movement of the slides to permit their sliding, uniaxial movement relative to the molded bars. To further enable this sliding movement between mold segments and the molded rack, the connecting supports between the top tier and the intermediate tier are provided on the sides of the rack, while the connecting supports between the intermediate tier and the bottom tier are provided on the front and rear of the rack.

Abstract: A single-piece, injection molded rack for holding test tubes or similar articles and a mold for producing the same. In a preferred three-tiered form, the intermediate tier is a lattice defined by the intersection of two superposed sets of parallel bars. These two sets of bars are formed by two pairs of correspondingly channeled slides that cooperatively engage to form a portion of the mold cavity corresponding to the lattice. The channels in each set of slides are aligned with the path of movement of the slides to permit their sliding, uniaxial movement relative to the molded bars. To further enable this sliding movement between mold segments and the molded rack, the connecting supports between the top tier and the intermediate tier are provided on the sides of the rack, while the connecting supports between the intermediate tier and the bottom tier are provided on the front and rear of the rack.

Abstract: A dental handpiece head having a bur-gripping mechanism which includes a spring-loaded ball carrier urged by the spring into operative engagement with a tapered ramp which in turn forces the several balls into clamping engagement with the shank of a dental bur positioned in the central bore of the ball carrier. The balls bite into the shank providing positive engagement. Downward force applied to the ball carrier against the spring, by a cam lever or by a pushbutton, releases the engagement.

Abstract: The disclosed invention is directed to a method of restoring a tooth with a light cured composite which comprises utilizing a light transparent impression or matrix which constitutes a negative reproduction of the occlusal surface of the tooth. The matrix is made by contacting the tooth surface with a polymeric impression material which when cured is light transparent and flexible. The polymeric impression material is allowed to set and then is stripped away from the tooth surface. A cavity preparation is then made in the tooth surface and treated in the usual manner. A light cured composite is then injected into the cavity preparation. The previously formed matrix is then placed over the light cured composite and pressure applied to the matrix. The composite is then cured by exposure to photopolymerizing light which passes through the transparent matrix. Following light curing, the matrix is stripped away from the tooth surface leaving a restored tooth with the original occlusal anatomy reproduced.

Abstract: A dental handpiece including motor portion and swivelable attachment portion. The motor portion includes an annular electrical commutator on its end facing the attachment. The attachment includes a lamp and associated electrical contacts for swivel contact with the commutator. The lamp illuminates the handpiece work area, either directly or through optical fibers. Swivelable chip air and water conduits in the motor/attachment combination are also disclosed.

Abstract: A two-piece, two chamber self-activating capsule having mercury in one chamber and metal powder in the other. In use, the capsule is shaken and the resulting force due to the inertia of the mercury forces its way through a normally-closed valve into the metal powder chamber, whereby the metal powder and mercury become triturated by the shaking and form dental amalgam for filling teeth. A pestle may be included to facilitate mingling and triturating the amalgam components.

Abstract: Monosodium phosphate is highly soluble in water and can be used as an ingredient for a low pH liquid buffer in a concentration of about 13-40 percent by weight. Tri potassium phosphate has good solubility in water and is a suitable ingredient for a high pH liquid buffer in a concentration of about 20-50 percent by weight. By a combination of these two ingredients, a system has been developed for using liquid buffer mixes in place of solid phosphate buffers, especially for use as a direct textile bath additive.

Abstract: A trifunctional methacrylate or acrylic terminated urethane resin of the following chemical structure: ##STR1## Where: R.sub.1 is --H, --CH.sub.3, --CH.sub.2 CH.sub.3, or --CH.sub.2 CH.sub.2 CH.sub.3,R.sub.2 is (--CH.sub.2 CH.sub.2 --O--).sub.n or ##STR2## where: n=2 to 10, R.sub.3 is a divalent organic radical obtained by removal of two isocyanato groups from an organic diisocyanate,R.sub.4 is methylene, ethylene or propylene, andR.sub.5 is --H, or --CH.sub.3.

Abstract: A hose having multiple conduits or conductors for transmitting drive air, water, chip air, light and/or electricity to a turbine-driven dental handpiece or other tool and for conveying exhaust air away from that handpiece, such hose being equipped with a plurality of swivel connectors for permitting the handpiece to be rotated a limited amount in each direction about its longitudinal axis with no objectionable restraint imposed, or restorative force exerted, by the conduits as they twist about each other during such handpiece rotation. In each disclosed embodiment, a plurality of the conduits have at least adjacent portions unattached to each other and individually provided with separate swivel connections.

Abstract: A swivel coupling for connecting a hose containing a drive air conduit, a secondary air conduit, a water conduit and an optical fiber conduit to a handpiece, such as a dental handpiece, having like conduits. The coupling permits unlimited swiveling, and efficient use of space by means of concentric annular passages in a central swivel tube.

Abstract: In a dental handpiece, a drawback bur chuck actuable to open by a cam lever mounted atop the handpiece head and acting axially downward on the chuck against a spring which urges the chuck upward into clamping engagement with a bur shank when the cam lever is in its closed position. The cam lever is rotatable on the axis of the chuck to a position to suit the convenience of the user. The chuck is removable for cleaning and positive means are provided to prevent over travel of the chuck to thereby prevent its permanent deformation.

Abstract: An orthodontic tensioning thread comprising a plurality of elastomeric strands braided together, the combined effect of the braid providing significantly improved tensile strength, elasticity retention, tieability and knot retention as compared to prior art monofilaments of comparable circumference.

Abstract: An electrically-heated dry bath wherein a metal block having receptacles for receiving test tubes or the like has resistor heaters fixed thereto and a thermistor temperature sensor therein. A control circuit is provided which connects and disconnects electrical current to and from said heaters in response to the temperature sensor. The control current is fedback such as to eliminate a factor J(S) from the overall transfer function of the circuit, J(S) being a transfer function expressing how various thermal time constants in the bath would, unless neutralized, make the effective time constant of the controlled system deviate from the ideal on-off transfer function.

Abstract: The present invention relates to new organosoluble manganese compounds.According to the invention these compounds are complex organometallic salts of organic or organometalloidic acids in which the ratio R of the number of acid equivalents to the number of manganese atoms is lower than 2. These are produced by reacting at moderately high temperatures in organic or aqueous/organic medium the organic acid with a manganous ammine complex, prepared in situ in the organic reaction medium.The compounds according to the invention are useful both as drying agents for paints and varnishes as well as combustion additives to liquid fuels.

Abstract: A microscope slide having a raised marking surface formed of pigmented resinous material, such as an epoxy resin, which dries to a matte finish which is absorptive and retentive of marking ink.

Abstract: An inert bead form polymer, of intermediate settling velocity between cation and anion exchange resins, which is dyed a highly visible color.

Abstract: A portable medication dispensing unit has several compartments for storing pills or other forms of medicine. The dispensing unit is programmed with a medication schedule which causes visual and audio signals when it is time for the medication to be consumed. The medication schedule is optimized to accommodate the user's personal habits and to simplify taking two or more medicines. The programming means may be integral with the dispensing unit or a separate unit.