Abstract: A method is disclosed for the manufacture of a ceramic material for fillings or dental prostheses, which includes the steps of forming a precipitation product having at least one slightly soluble calcium phosphate compound, which has at least two phases of crystals; the slightly soluble calcium phosphate compound being a replacement for dental tissue. The precipitation product further includes a freely soluble compound dissolvable in the saliva of a patient's mouth and which creates a porous structure within the slightly soluble phase. The pores of this structure are filled by precipitating ions from the patient's saliva. The precipitation product is then sintered and dried, before being explosively compressed to form the ceramic dental filing material.

Abstract: An apparatus for drawing off dust-laden gases, especially in the art of dental technique, has a ring channel (15) which can be loaded with compressed air. The airstream which is provided by a compressed-air nozzle (26) performs an arcuate movement in the ring channel (15), whereby dust-laden gases are drawn in through an annular slit (22) and conveyed to an outlet channel (13). The apparatus is suitable for drawing off gases from containers. The apparatus serves for drawing off dust-laden air which is released when mixing solid substances, for example dental investment material, in a container (10).

Abstract: The invention is directed to the creation of a material which does not have the hazardous properties of prior art materials containing quartz. In the material according to the invention, quartz is replaced with a quartz-free magmatic rock, especially nepheline syenite. Surprisingly, the magmatic rock in powdered form attains nearly the same treatment results as conventional materials which contain quartz. The material according to the invention is particularly suitable for polishing and blasting dental parts, especially those parts which are made of plastic material.

Abstract: The variation with time of the temperature is analyzed during the heating-up of a melting charge in dental engineering. If the slope (d.theta./dt) of the temperature curve changes by a predetermined measure, this is used for detecting the liquidus point. Time and/or temperature for casting the melt are determined by a criterion (.DELTA..theta.; .DELTA.t) referring to the liquidus point determined in this manner. The values determined for the casting time and other casting parameters are stored and used as controlling variables for subsequent melting and casting processes. In addition, the entire temperature variations of successive processes can be stored. A subsequently measured temperature variation is compared with the stored temperature variations during the measurement (section by section). In the case of agreement (within predetermined tolerances) an identified stored temperature variation is used as nominal variation for the further melting and casting process.