Abstract: The invention relates to a mold for producing the model of a tooth from a dental impression (28), comprising a peripheral wall (12), a model plate (38) which is tightly arranged on the top thereof and an impression spoon (14) bearing the dental impression (28). Said spoon is tightly inserted into the lower end of the peripheral wall (12). The hollow cavity (42) thus obtained is filled with molding material to give a highly precise tooth model requiring no further mechanical processing.

Abstract: For ultrasonic preparation of hard or soft tissues or of tissue replacement material a apparatus is proposed comprising a hand piece (10), which includes an ultrasonic vibration generator (16), an ultrasonics deflecting head (28) as well as a tool (36) carried by the output member of the deflecting head. An abrasive treatment medium (48) is supplied to the working region defined between the tool (36) and the material (66) to be prepared. Thus even in places, which are difficult to access, cavities can be produced in dental or bone tissue in a gentle and precise manner.

Abstract: A process for the production of .alpha.-tocopherol esters, derivatives or homologs thereof of the general formula ##STR1## in which the mono- or diester of a hydroquinone is reacted with an allyl alcohol derivative or an allyl alcohol in the presence of zinc halides and proton-liberating acids at a temperature of 25.degree. to 100.degree. C.

Abstract: A tooth cleaning apparatus has a working surface formed by fibrous cleaning elements of different lengths and of very small diameters at their working ends. The cleaning elements are fixed on a base fabric, which is reinforced by a foam layer and thus forms a deformable hollow unit that is then attached to a handle. The pile-like cleaning elements facilitate very effective cleaning even of the fine surface contours of curved tooth surfaces.

Abstract: A method of producing 3,5,5-trimethylcyclohexa-3-ene-1-one (.beta.-isophorone) by isomerization of 3,5,5-trimethylcyclohexa-2-ene-1-one (.alpha.-isophorone) in a liquid phase in the presence of a homogeneous or heterogeneous catalyst in which a mixture with a relatively low concentration of .beta.-isophorone is drawn off from the reaction container and the .beta.-isophorone isolated by vacuum distillation. .beta.-isophorone is an important synthetic structural element for the production of carotinoids, vitamins and pharmaceutical products.

Abstract: An improved method of producing 3,5,5-trimethylcyclohex-2-ene-1,4-dione (KIP) by the oxidation of 3,5,5-trimethylcyclohex-3-ene-1-one (.beta.-IP) in the presence of managansalene-like catalysts and certain catalytic additives. ##STR1## KIP is an important intermediary product in the synthesis of trimethylhydroquinone, an initial substance in the synthesis of vitamin E. Furthermore, KIP is an initial compound for the synthesis of various carotinoids.

Abstract: A shaped article, specifically an artificial tooth, is made of two parts. individually shaped first part 18, specifically the head part or superstructure of the artificial tooth, has a standardized locking portion 26 for engagement with a standardized counter-locking portion 24 provided on a pre-fabricated second part 16, specifically the shaft part of the tooth to be implanted in a patient's jaw. The individually shaped part 18 is manufactured by using a pre-fabricated sonotrode 38 for producing the configuration of the locking portion 26 and one or more individually produced shaping sonotrodes 44 are used for generating the parts of the surface other than the locking portion 26. This permits the individually shaped part to be produced in an economic way yet with high precision of the locking portion.

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: 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: An apparatus is provided for the selection of a tooth color for a dental prostheses in which an exact adaptation of the colors or color distribution of a dental prosthesis to a particular structural condition in a patient can be achieved. The apparatus, a platelet color specimen, has at least one lateral edge concavely curved towards a center region of the platelet. The platelet color specimen is on the order of magnitude of only a width of a tooth, and can be placed contiguous with the surface and edge of all exposed portions of a tooth. The platelet color specimen also exhibits only a single color corresponding to enamel, dentin or dental neck which allows for an exact adaptation to a particular patient.

Abstract: A chemical oxygen generator includes a candle in which oxygen is present and which is chemically combined and which is ignited by starting means to initiate the generation of the oxygen. This takes several seconds before a substantial quantity of oxygen is provided. Because a user of this oxygen must be supplied with the oxygen for respiration immediately, the invention includes a generator which has a pressure space, preferably above, below and around the oxygen candle which is located in the space and which is filled with compressed oxygen. The generator includes a member which is actuated upon release of the starting means for the oxygen to permit outward flow of the oxygen in the pressure space which is supplied until the oxygen being released from the candle is produced by the ignition of the candle.

Abstract: A chemical oxygen generator is disclosed which includes a pressure vessel surrounding the container containing the chemical. In a space between the tank containing the chemical and the wall of the pressure vessel, a supply of pressurized oxygen is provided. A manually triggerable valve stem is operable to simultaneously open a passage from the pressurized supply and to initiate ignition of the chemical in the tank to generate a further supply of oxygen.

Abstract: A breathing gas supply controller, comprises a housing which has a gas inlet leading to an internal gas passage which opens at the opposite end in a gas supply opening for supplying gas to a place of use, such as to aid in a person's respiration. The interior gas passage has a widened portion with an elastic valve tube in the passage which defines an annular pressure chamber around the tube which is separated from the passage. A valve member extends through the passage and it includes an intermediate annular widened portion which is engaged against the interior of the valve tube in a closed position to close off the gas passage. A control chamber, which is defined in the housing, has a first control passage communicating with the pressure chamber and a second control passage communicating with the gas passage on the downstream or gas supply end thereof.