Abstract: The invention relates to impression compositions based on vulcanizable polyether materials, which are characterized in that the ready-mixed pastes comprise a) approx. 30 to 70 wt. % of aziridino-polyether, b) approx. 5 to 20 wt. % of a triacyl glyceride of non-animal origin which has a stearoyl content of ≧70 wt. %, based on the acyl content of the triacyl glyceride, or, in the case of a lower stearoyl content and if this adversely influences the storage stability of the impression composition, has been esterified in itself beforehand, and c) approx. 10 to 65 wt. % of customary catalysts, auxiliaries and additives, in each case based on the total weight of the composition. The impression compositions are distinguished by consistently good mechanical properties of the polymerized materials, have a comparatively low proportion of aziridino-polyether, which has a favorable effect on their preparation costs, and can easily be mixed.

Abstract: The invention relates to impression compositions based on vulcanizable pother materials, which are characterized in that the ready-mixed pastes comprisea) approx. 30 to 70 wt. % of aziridino-polyether,b) approx. 5 to 20 wt. % of a triacyl glyceride of non-animal origin which has a stearoyl content of .gtoreq.70 wt. %, based on the acyl content of the triacyl glyceride, or, in the case of a lower stearoyl content and if this adversely influences the storage stability of the impression composition, has been esterified in itself beforehand, andc) approx. 10 to 65 wt. % of customary catalysts, auxiliaries and additives,in each case based on the total weight of the composition.The impression compositions are distinguished by consistently good mechanical properties of the polymerized materials, have a comparatively low proportion of aziridino-polyether, which has a favourable effect on their preparation costs, and can easily be mixed.

Abstract: A device for emptying a film tube 15 containing a pasty substance comprises a cap structure 11 including a transverse wall 12 supporting the front of the tube, a cylindrical flange 13 formed on the wall for receiving the front end of the tube, and a dispensing pipe 17. The pipe 17 extends from a recess 16 formed in the wall 12 and having an at least partially circular-cylindrical shape, with a spike 18 being integrally formed at the center of the recess and extending parallel to the axis of the tube. The tip 19 of the spike is retracted from the plane of the wall 12. When dispensing pressure is exerted on the tube 15, the portion of the tube film overlying the recess 16 will bulge into the recess, until its central part is scratched by the tip 19 of the spike and thus caused to burst. The content of the tube can then flow into the recess 16 surrounding the spike 18 and out through the pipe 17.

Abstract: An addition-crosslinking polyether impression material is described which ntains(a) at least one polyether which has at least two optionally substituted vinyl and/or allyl end-groups,(b) an SiH component,(c) at least one platinum catalyst,(d) optionally usual additives, and(e) an organopolysiloxane with at least two alkenyl groups.The impression material has in at least two-part form of administration in which the components (b) and (c) are spatially separated from each other a particularly satisfactory storage stability and has good mechanical properties in the cured state.

Abstract: The invention relates to fluoride-releasing, polymerizable dental composite aterials having good mechanical stability, containing:(a) one or more ethylenically unsaturated polymerizable monomers based on di- or multi-functional (meth)acrylates;(b) initiators and optionally activators; and(c) usual fillers, and optionally pigments, thixotropic agents, plasticizers and other auxiliaries; and(d) one or more sufficiently water-soluble inorganic complex fluorides of the general formulaA.sub.n MF.sub.mwherein,A is a monovalent cation, M is a metal of the III-V main group or II-V sub-group, n is a whole number from 1 to 3 and m is whole number from 3 to 6.

Abstract: A dental restoration part is produced from a ceramic material by a method ultrasonic working. The method includes forming a negative mold from a master sonotrode, forming a pre-working sonotrode from the negative mold, and ultrasonically working a workpiece using the pre-working sonotrode. The master sonotrode is then used to ultrasonically work the workpiece to form the dental restoration part.

Abstract: For emptying a film tube 15 containing a flowable substance, the front end f the tube is provided with a ring 17 the peripheral portion 19 of which exceeds the inner diameter of a cartridge 1 which receives the tube 15. The ring 17 has a conical sealing surface 20 which cooperates with a sealing edge 12 formed inside the cap 2. In operation, the cylindrical rear portion 7 of the cap 2 is slid onto a front portion 4 of the cartridge 1, whereby the ring 17 provided on the tube 15 has its sealing surface 20 centered and aligned in the radial and axial directions to ensure proper engagement between the sealing edge 12 and the sealing surface 20.

Abstract: The invention relates to a rubber-elastic composition which comprises a polyether material, and which in the completely vulcanized and completely polymerized form, contain 0.1 to 15 wt. %, relative to the total weight of the composition, of at least one hydrophilic nature imparting agent selecting from the group consisting of a hydrophilic silicone oil having one or more siloxane groups as a hydrophobic part and one or more ether groups as a hydrophilic part, a fluorinated hydro-carbon, a block copolymer of ethylene oxide/propylene oxide, a fatty alcohol derivative, an alkyl phenol derivative, a fatty amine, an amine oxide, a fatty acid glycol and glycerin derivative, a fatty acid, and a fatty acid monoester. The composition is suitable as dental impression composition and has, in the completely polymerized state, even with multiple disinfections in an aqueous disinfecting solution, a continuing good ability to flow on (small wetting angle) and an unchanged dimensional stability.

Abstract: There are provided formable compositions which comprise:(A) 25 to 80% by weight of a glass ionomer cement, containing (a) an aluminum fluorosilicate glass, (b) at least one polymeric polyacid with an average molecular weight >500, (c) water and (d) optionally a chelating agent;(B) and 20 to 75% by weight of a fluoride and/or oxide and/or mixed fluoride and/or mixed oxide of heavy metal elements which are essentially insoluble at ambient temperatures in an aqueous solution containing the polymeric polyacid and/or an aqueous solution containing the chelating agent.The compositions are especially well suited as filling materials for dental root canals.

Abstract: For emptying a film tube 15 containing a flowable substance, the front end f the tube is provided with a ring 17 the peripheral portion 19 of which exceeds the inner diameter of a cartridge 1 which receives the tube 15. The ring 17 has a conical sealing surface 20 which cooperates with a sealing edge 12 formed inside the cap 2. In operation, the cylindrical rear portion 7 of the cap 2 is slid onto a front portion 4 of the cartridge 1, whereby the ring 17 provided on the tube 15 has its sealing surface 20 centered and aligned in the radial and axial directions to ensure proper engagement between the sealing edge 12 and the sealing surface 20.

Abstract: In a process and apparatus for the overall machining of a ceramic tooth restoration and producing of appropriate sonotrode crowns, these sonotrode crowns act on a workpiece one after the other, however from the same direction in space and are activated by the same ultrasonic transmitter. For the production of said sonotrode crowns, a geometrical model corresponding to the ultrasonic machining apparatus is used.

Abstract: Bone replacement parts consisting of glass ionomer cement are superior to those made of ceramics especially since they may easily be produced and machined using common grinding and milling tools. The required prosthesis part may therefore be formed of freshly mixed glass ionomer cement during the respective operation, or an industrially prefabricated formed body approximating the idealized shape of the bone part to be replaced may be adapted to the anatomic conditions given.

Abstract: A process of preparing a substrate surface for a subsequent adhesive bond, coating or pouring operation, by applying to the substrate an adhesion promoting composition comprising either:(A), (B) and (C); or (A) and (C); or (B) and (C); or (B) of the following ingredients (A)-(C):(A) 0.01 to 90 wt. % of optionally silanized material with a particle size <5 .mu.m and a hardness greater than that of the substrate surface,(B) 20 to 100 wt. % of silanized, silicon-containing material with an average particle size of 2 to 2100 .mu.m,(C) an abrasion agent with a particle size 5 .mu.m as the remainder;wherein the quantities quoted are relative to the total weight of (A)-(C). In the process the composition is applied to the substrate surface using horizontal or predominantly horizontal forces of friction, so that an adhesion promoting layer is formed on the substrate surface.

Abstract: The container includes a film tube 11 for flowable substances. The film t is opened and placed in a cylindrical housing 31 between a cap 33 and a movable piston 32. At the end facing the cap 33, the tube 11 is provided with a ring 20 which has a conical sealing surface 21. When the piston 32 is advanced to dispense the content of the tube 11, the sealing surface 21 is forced against a complementary conical counter surface 35 formed in the cap 33 and surrounding an outlet. The content of the tube 11 is thus prevented from reaching the inner wall of the housing.

Abstract: The invention relates to an apatite glass ceramic which can be used as a material in medicine and as an inorganic component of a glass ionomer cement. The apatite glass ceramic comprises in wt-%) 15-40% SiO.sub.2, 15-35% Al.sub.2 O.sub.3, 12-30% CaO, 6-25% P.sub.2 O.sub.5, 2.5-15% F.sup.-, 0-18% R.sub.2 O, wherein R.sub.2 O is an alkali oxide. The apatite glass ceramic comprises a crystal phase which contains apatite.

Abstract: Bone replacement parts consisting of glass ionomer cement are superior to those made of ceramics especially since they may easily be produced and machined using common grinding and milling tools. The required prosthesis part may therefore be formed of freshly mixed glass ionomer cement during the respective operation, or an industrially prefabricated formed body approximating the idealized shape of the bone part to be replaced may be adapted to the anatomic conditions given.

Abstract: A dynamic mixer comprises a cylindrical chamber portion 50 the rear end of hich is closed by a sealing plate 51 provided with conical pipe sockets 58, 59 adapted for being directly inserted into outlet openings of cartridges from which the pasty components to be mixed are supplied. Due to the closed structure of the mixer housing 50, 51, contamination of the device by the components and cross-contamination between them is avoided when the mixer is removed from the cartridges. Further, the direct connection of the mixer to the cartridges results in minimum travelling distances for the components, thus low friction losses, which is particularly advantageous in case of substances of high-viscosity.

Abstract: Curable compositions are described which contain a binder and a high propion of fillers having a mean grain size of <50 .mu.m. The filler proportion of the curable compositions is so high that they cannot be used for the intended purpose because of their high viscosity However, they can be liquefied by exposure to oscillation in the frequency range of 20 Hz to 20 MHz with an amplitude of 1 .mu.m to 5 mm so that they are workable and can be employed for the intended purpose.

Abstract: A hand-held sand blasting device, which is particularly useful for treating mall surface areas, such as tooth faces in situ, includes a sand cartridge 20 adapted to be placed in a handle portion 10 of the device and rewardly sealed by a piston 34 which is adapted to be advanced by pressurized air. Part of the pressurized air flows along a longitudinal groove 25 formed in a wall of the handle portion 10 externally of the cartridge 20 and enters the cartridge through an opening 27 provided at a front portion thereof, where the relatively large cross-section of the main portion of the cartridge converges to the substantially smaller cross-section of a feed channel 28. The fine sand 21 is thus fluidized in this area and maintained flowable. Through the feed channel 28, the sand is supplied to a mixing chamber 30 where it is mixed with pressurized air and discharged through a nozzle pipe 33.

Abstract: A method for bonding or potting substrates by means of cationically polymerizable masses being activated before joining or potting by irradiation with visible light and curing after joining or potting of the substrates without the irradiation being continued is described as well as an apparatus for executing this method. By irradiation with light having a wavelength of from 400 to 600 nm for photo-activation of said masses, a prolonged pot life of said masses without reducing their wetting ability during pot life is obtained such that the masses are unlimitedly applicable for more than 30, preferably more than 100 sec. after exposure is finished. The apparatus according to the invention comprises a source of irradiation which exclusively emits light having a wavelength of >400 nm.