摘要:
A method for manufacturing a shaped body, comprising creating a mixture of a metal powder and binding agent, compacting the mixture to form a green compact, heating the green compact to a debinding start temperature T1, debinding the green compact by controlled heating of the green compact from start temperature T1 to end temperature T2 at a heat-up rate R1, presintering the debindered green compact to the presinter end temperature TVS at a heat-up rate RHVS, cooling the green compact from the presinter end temperature TVS at a cool-down rate RKVS, whereby at least the heat-up rate RHVS, the presinter end temperature TVS, and the cool-down rate RKVS are tuned relative to each other in such a way that the presintered green compact forming a blank has a surface porosity of 16% to 22% after presintering, and machining and sintering of the blank to form the shaped body.
摘要:
The invention concerns a process for the polishing of metallic dental prostheses, such as frames. In order to reproducibly obtain a defined surface roughness with no need for additional finishing, it is proposed for the dental prosthesis to be polished by means of plasma polishing.
摘要:
A method for manufacturing a multipart assembly of sintered oxide ceramic material, including one first component which at least partially surrounds one second component in such a manner that detaching the first component from the second component is not possible without destroying the first and/or second component. The assembly is produced by producing a single-part first shaped part and a single-part second shaped part from an oxide ceramic blank, whereby the first shaped part and the second shaped part are enlarged to compensate for the shrinkage during sintering, and assembling the sintered shaped part as second component with the first shaped part and subsequently sintering them together. As the first shaped part is employed a shaped part with an opening whose effective cross section after sintering is either smaller than the effective cross section of the second shaped part after sintering in a region that extends within the first component, or is smaller that the effective cross section of the second component in front of and behind the opening.
摘要:
A method for manufacturing a multipart assembly of sintered oxide ceramic material, including one first component which at least partially surrounds one second component in such a manner that detaching the first component from the second component is not possible without destroying the first and/or second component. The assembly is produced by producing a single-part first shaped part and a single-part second shaped part from an oxide ceramic blank, whereby the first shaped part and the second shaped part are enlarged to compensate for the shrinkage during sintering, and assembling the sintered shaped part as second component with the first shaped part and subsequently sintering them together. As the first shaped part is employed a shaped part with an opening whose effective cross section after sintering is either smaller than the effective cross section of the second shaped part after sintering in a region that extends within the first component, or is smaller that the effective cross section of the second component in front of and behind the opening.
摘要:
The invention relates to a process for determining the form a duplicate of a residual tooth area, which is to be fitted with a dental restoration whereby the duplicate sections to be fitted with the restoration are removed from the duplicate and the form data to be allocated to their forms has to be determined and stored in a computer, by means of which the form of the restoration is calculated taking into consideration the spatial allocation of the duplicate sections. In order to be able to determine the shape of the residual tooth area to be fitted with the restoration, and thereby determine the shape of the restoration itself with high precision, it is proposed that the duplicate sections are or are being individually referenced to each other in their spatial allocation to each other according to a referencing stored in the computer.
摘要:
A method for manufacturing a shaped body, comprising creating a mixture of a metal powder and binding agent, compacting the mixture to form a green compact, heating the green compact to a debinding start temperature T1, debinding the green compact by controlled heating of the green compact from start temperature T1 to end temperature T2 at a heat-up rate R1, presintering the debindered green compact to the presinter end temperature TVS at a heat-up rate RHVS, cooling the green compact from the presinter end temperature TVS at a cool-down rate RKVS, whereby at least the heat-up rate RHVS, the presinter end temperature TVS, and the cool-down rate RKVS are tuned relative to each other in such a way that the presintered green compact forming a blank has a surface porosity of 16% to 22% after presintering, and machining and sintering of the blank to form the shaped body.
摘要:
The invention concerns a process for the polishing of metallic dental prostheses, such as frames. In order to reproducibly obtain a defined surface roughness with no need for additional finishing, it is proposed for the dental prosthesis to be polished by means of plasma polishing.
摘要:
The invention relates to a method and an apparatus for a non-contact, three-dimensional determination of the shape of a dental technology object (10) whereby, to determine the space coordinates of the object's surface points to be measured, a thin stripe of light projected onto the object is measured by at least two matrix cameras (32, 34) to determine two space coordinates (Z- Y-coordinate) of a coordinate system, and the third space coordinate (X coordinate) is ascertained by determining the position of the object arranged on a measuring table (22) which is rotatable about an axis of rotation (20). For allowing, in an easy manner, a non-contact determination of the shape of the dental technology object, whereby the constructive effort to determine the spatial coordinates is kept low and the shape acquisition should still be performed highly precisely and at high speed, it is provided that the matrix camera is a color matrix camera with first, second and third pixels, that the matrix camera captures light in a range of wave lengths characteristic for one type of the pixels (first pixels) and the values at least of one of the other types of the pixels (second and third pixels) are analyzed to determine the two first location coordinates (Y- and Z-coordinates).
摘要:
A dental alloy with a high gold content that is devoid of palladium and copper. To achieve high mechanical stability, the dental alloy contains between 75 and 95 wt. % Au, between 5 and 20 wt. % Pt, between 0.5 and 3.5 wt. % Zn and/or Sn and/or In, between 0.1 and 0.8 wt. % of an element of a group I, in addition to a single particle refiner of a group II. The weight fraction of the element of group I is between 2 and 6 times that of the single particle refiner of group II, and one element of group I is represented by Nb or Ta or Ti or V and the particle refiner of group II is represented by Ir or Rh.
摘要:
A process for determining 3-D data of at least one prepared jaw area, such as a prepared tooth stump, by mechanically scanning the jaw area and digitizing the measured values determined during the scanning. The jaw area is prepared with a dental instrument having positions which are optically measured during the preparation, and the 3-D data is determined from the positions of the dental instrument that are associated with the prepared jaw area.