Abstract: Dental compositions based on an bifunctional or polyfunctional acrylic-acid and/or methacrylic-acid esters, which contain an initiator system for radical polymerization and which additionally contain a compound of the general formula ##STR1## in which: Ar represents aryl or substituted aryl,R.sup.1, R.sup.2 and R.sup.3 represent hydrogen, aryl or substituted aryl, straight-chain or branched chain C.sub.1-18 -alkyl, C.sub.1-18 -alkoxyl or C.sub.1-17 -alkoxycarbonyl, in which alkyl and alkoxyl can be substituted by halogen or aryl,in which, R.sup.1 or R.sup.2, when represented by aryl or substituted aryl, C.sub.1-18 -alkyl or C.sub.1-18 -alkoxyl, can be linked with Ar by a single-bond andin which, Ar, when represented by phenyl, C.sub.1-18 -alkylphenyl, C.sub.1-18 -alkoxylphenyl, carboxyl-C.sub.1-17 -alkylphenyl or halogenphenyl, R.sup.2 can be represented by --O--, which is linked with the phenyl or phenyl moiety of Ar to a benzofuran, andin which at least one of R.sup.1 to R.sup.

Abstract: Dental compositions based on an at least bifunctional or polyfunctional acrylic-acid and/or methacrylic-acid esters, which contain an initiator system for radical polymerization and which additionally contain a compound of the general formula ##STR1## in which: Ar represents aryl or substituted aryl,R.sup.1, R.sup.2 and R.sup.3 represent hydrogen, aryl or substituted aryl, straight-chain or branched chain C.sub.1-18 -alkyl, C.sub.1-18 -alkoxyl or C.sub.1-17 -alkoxycarbonyl, in which alkyl and alkoxyl can be substituted by halogen or aryl,in which, R.sup.1 or R.sup.2, when represented by aryl or substituted aryl, C.sub.1-18 -alkyl or C.sub.1-18 -alkoxyl, can be linked with Ar by a single-bond andin which, Ar, when represented by phenyl, C.sub.1-18 -alkylphenyl, C.sub.1-18 -alkoxylphenyl, carboxyl-C.sub.1-17 -alkylphenyl or halogenphenyl, R.sup.2 can be represented by --O--, which is linked with the phenyl or phenyl moiety of Ar to a benzofuran, andin which at least one of R.sup.1 to R.sup.

Abstract: An explosive powder charge operated setting tool contains a channel (7) located between an inner piston guide (2) for a piston (1) and an outer housing part (6). At the rear end of the tool, the channel (7) continues in a carrier (3) and can be in communication with a cartridge receptacle (4) in the carrier (3). In its front region, the channel (7) is connected via a first opening (2c) in the piston guide (2) with a guide bore (2a) for the piston (1). Towards the rear end of the channel (7) there is a valve arrangement for forming a propellant gas storage space connected through the first opening (2c) to the guide bore (2a). Propellant gases within the storage space are compressed by the piston (1) driven in the setting direction and, after completion of the driving or setting procedure, serve to return the piston (1) back into its rear starting position by expansion of the storage space gases.

Abstract: The invention relates to photopolymerizable dental compositions of ethylenically unsaturated monomers and/or polymers thereof which are curable in two curing steps. Besides being comprised of fillers, said compositions also contain a photoinitiator component I having a light absorption maximum of <450 nm and a molar extinction of the light absorption of <10 at wavelengths of 470 nm or higher, and a photoinitiator component II having a molar extinction of the light absorption of >20 at least at one wavelength of at least >450 nm.

Abstract: An explosive powder charge operated setting tool uses compressed propellant gases for returning a piston (1) from an end position to a starting position. The piston (1) is axially displaceable by the propellant gases within an axially extending guide bore (2a) in a piston guide (2). The propellant gases flow from the guide bore (2a) through a first opening (6) into an axially extending channel (5) outside the piston guide (2) and then through a second opening (7) in the region of the end position of the piston (1) back to the guide bore. After the piston (1) is driven into the end position, compressed propellant gases within the guide bore (2a) return the piston to the starting position where it impacts against the base (4c) of a cartridge carrier (4) located at the starting position. When the piston (1) is stopped, the cartridge carrier (4) is displaced to a limited extent opposite to the setting direction of the tool.

Abstract: Powder charge operated setting tool includes a barrel (11) and a closing or breech member (17), axially displaceable within a housing 1. Stops (3a, 17a) and shoulders (8b, 11e) cooperating with each other are provided in the housing (1) and on the barrel (11) as well as on the closing member (17) which limit displacement of the barrel (11) and, after an additional displacement travel, the displacement of the closing member (17) counter to the setting direction. As a result a free space is formed between the barrel (11) and the closing member (17) which permits feeding of propellant charges (15), especially in magazines, perpendicularly to the axis of the barrel.

Abstract: Open-pored moldings containing the product of the foaming and setting of (a) an aluminum fluorosilicate glass, (b) at least one polycarboxylic acid with an average molecular weight of >500, (c) a foaming agent, other than carbonates and/or hydrogen-carbonates, (d) optionally a chelating agent and (e) water, are suitable in particular as bone substitute material.Production is carried out by homogeneously mixing (a), (b), (c), optionally (d), and (e), then foaming, shaping and setting.

Abstract: A powder charge operated setting tool includes a barrel (5) and a closing or breech member (8), both axially displaceable in a housing (1). Tensioning of a tension spring (18) for a firing pin (17) is made possible by means of a disengageable snap-in element (12) acting between housing (1) and closing member (8) by pressing the barrel (5) against the receiving material. The disengagement of the snap-in element (12) occurs only by overcoming a predetermined force acting counter to the setting direction which is generated by the gas pressure after a propellant charge (19) has been ignited.

Abstract: Photopolymerizable dental compositions are proposed which are curable with visible light and which apart from usual auxiliary substances and additives contain polymerizable monomers of the group of the poly-thiol compounds and of the group of the poly-ene compounds and a photoinitiator and which, in order to obtain a curing free from any smeary layer, contain at least 10% by weight poly-thiol compound(s), at least 10% by weight poly-ene compound(s) and 0.01 to 5% by weight of at least one acyl phosphine compound as photoinitiator. The compositions can advantageously be used as dental impression compositions.

Abstract: A polyether-impression material comprising components(a) a polyether, which has at least two optionally substituted vinyl- and/or allyl-end groups,(b) an SiH component,(c) a platinum catalyst, and optionally(d) the usual additivescharacterized in that the SiH-component (b) can be obtained by the reaction of at least a bi- functional, or polyfunctional, e.g., trifunctional, allyl- or vinyl-hydrocarbon compound, the hydrocarbon radical of which, without taking account of the allyl- or vinyl-groups and the optionally present alkylene ether groups, has 6 to 30 C-atom and contains at least one aromatically unsaturated, heterocyclic, or cycloaliphatic ring, with at least one mole per vinyl- or allyl-group of at least a bifunctional, or polyfunctional, e.g., trifunctional, SiH compound of the formula: ##STR1## in which e=0 to 8,g=0 to 8,h=0 to 4 andR.sup.4 and R.sup.10 are the same or different, and are each H, methyl or ethyl, with the proviso that at least 1 and at the most 5 of R.sup.4 to R.sup.

Abstract: A fastening element to be driven into a hard receiving material, such as metal, includes a head at its trailing end and an axially extending shank projecting from the head to the leading end with a tip at the leading end. At least an axially extending section of the shank from adjacent the trailing end is threaded. A guide member is in threaded engagement with the shank and is spaced from the head when the fastening element is ready to be driven. The guide member is cup-like shaped with an opening facing toward the leading end. The guide member has a base extending transversely of the axial direction with a conically shaped section projecting radially outwardly from the base and axially toward the leading end. When the fastening element is driven into a receiving material, the guide member moves into contact with the head and is deformed when the driving of the fastening element is braked.

Abstract: In an explosive powder actuated setting device, a driving piston (8) is displaceable between a ready-to-fire position and a fired position within a barrel (12) formed by a piston guide (5). When the piston is driven from the ready-to-fire position into the fired position, it is held by braking balls (17) supported in recesses (16) in the piston guide. As it moves into the fired position, the piston moves the braking balls into the range of a spring (18) which biases the balls inwardly against the shank (11) of the piston (8). When the piston is returned into the ready-to-fire position, the balls move out of the range of the spring releasing the biasing force acting on the piston shank via the balls.

Abstract: An ionogenic compound, soluble or dispersible in aziridine compounds is utilized for delaying the polymerization of aziridine compounds initiated by a sulfonium salt. Said ionogenic compounds contain an anion which is more nucleophilic than the anion present in the sulfonium salt employed. Moreover, a preparation for dental purposes is described which contains these components.

Abstract: (Methy)acrylic acid esters of the general formula(Mo).sub.n --[--A--O--CO--CH.sub.2 --O--CH.sub.2 --CH.sub.2 --O--CH.sub.2 --CO--O--].sub.x --A--(OM).sub.nare described whereinA is an alcohol radical having at least 4 chain atoms between two junction sites.M is CH.sub.2 .dbd.C(R.sup.1)--CO wherein R.sup.1 stands for hydrogen or methyl,n is 1 or 2, andx is 0.3 to 3.These esters are suited for the preparation of dental compositions.

Abstract: An explosive powder charge actuated fastening element driving device includes a driving piston mounted within a guide bore in an axially extending piston guide for displacement between a firing position and a driving position where the fastening element is driven into a receiving material. After driving a fastening element, the driving piston is returned toward the firing position by exhaust gases generated when a charge is fired. A channel laterally encloses the piston guide with a first and a second aperture, spaced apart in the axial direction, extending through the piston guide communicating between the guide bore and the channel. A blocking slide movable relative to the piston guide is located within the channel.

Abstract: A setting device arranged to use caseless propellent charges for driving fastening elements, such as bolts, nails and the like, into a hard receiving material, includes a casing containing an axially slidable barrel forming a feed element at its rearward end. A counterpressure member is slidably movably supported within the casing in axial alignment with the barrel. The feed element and counterpressure member combine to form a combustion chamber for the caseless propellent charges. A frusto-conical surface is formed on the counterpressure member and seats in sealing contact with a complementary frusto-conical surface in the casing.

Abstract: In an explosive charge operated device for driving fastening elements into a receiving material, a throttling device is arranged for conveying explosive gases from a barrel out of the device housing. The throttling device is a tubular member containing a displaceable nozzle needle. The position of the nozzle needle controls the flow of gas out of the tubular member. When an explosive charge is fired, the barrel is axially displaceable opposite to the direction for driving a fastening element from the device. As the barrel is displaced the throttling cross-section through the throttling member is increased as the throttling member is displaced so that the outflow of the explosive gases and the peak values of the sound level is considerably reduced as compared to similar previously known devices.

Abstract: A powder charge operated fastening element setting device includes a housing, a barrel forming an axially extending bore with the barrel being axially and rotationally displaceable within the housing. An axially extending driving piston is located in the barrel bore and is axially displaceable therein between a ready-to-fire position and a fired position. A guide bush is located within the housing at the rear end of the barrel and is coextensive with an axially extended part of the barrel. The guide bush is secured against rotation relative to the housing. Propellant gases are generated in combustion chamber in the guide bush and flow into the barrel bore. The force of the propellant gases for propelling the driving piston can be regulated by at least one outlet opening adjacent the rear end of the barrel which can be selectively connected to an outlet flow duct in the guide bushing which opens to the atmosphere.

Abstract: 1,2,6-Thiadiazine-3,5-dione-1,1-dioxides of the general formula ##STR1## wherein each R and R.sub.3 independently may be substituted or unsubstituted alkyl, alkenyl or substituted cycloalkyl are described. These compounds, as well as those wherein the R substituents additionally may be cycloalkyl or substituted or unsubstituted aryl, are useful as accelerators for the peroxidic polymerization of ethylenically unsaturated compounds, such as methacrylic acid compounds, and have particular utility in dental compositions.

Abstract: Polyvinyl butyral with a degree of acetalization of at least 75% is added to a dental cement on basis of calcium hydroxide and salicyclic esters of aliphatic alcohols. By this additive improved water resistance and increased compressive strength upon hardening are imparted to the dental cement. The obtained dental cement furthermore has strongly alkaline pH value, so that an effective protection of the pulp can be achieved and formation of a secondary dentin layer is stimulated. In the common formulation of the materials for the dental cement in form of two separate mixing components the polyvinyl butyral can be added either to the mixing component containing the salicylic acid ester or to the mixing component containing the calcium hydroxide, or also to both components.