An electromotive linear drive in the form of a dual drive adjust movably mounted parts of reclining and seating furniture. Two threaded spindles (2, 3) driven by a worm gear and which are arranged one behind the other and flush with one another for displacing a lifting element. Bearings are provided at both ends of each threaded spindle (2, 3). The bearings are designed as roller bearings (4, 5) having an inner ring (6) and an outer ring (7). The aim of the invention is to design an electromotive dual drive in such a way that a short overall length is achieved and that the stability of the structure is increased. Said aim is achieved by arranging an abutment between both roller bearings (4, 5), which accommodate the spindle ends, on which the roller bearings are supported on from both sides.

Dental articles and methods of using same. The dental article (510) includes a shell defining a volume, the shell (512) comprising a circumferential base (514) and an incisal/occlusal region (516) distal from the circumferential base. The dental article (510) further includes a hardenable dental composition (518) located within the volume, and an isolation film (520) located at the circumferential base of the shell.

The invention relates to a process of selectively treating parts of the surface of a porous dental ceramic comprising the steps of a) providing a composition and a porous dental ceramic having an outer surface, b) applying the composition to only a part of the outer surface of the porous dental ceramic, c) optionally drying the porous dental ceramic, and d) optionally firing the porous dental ceramic, wherein the composition comprises—a liquid being miscible with water, but not being water, —a whitening agent comprising nano-sized metal oxide particles, metal ion containing components or mixtures thereof which precipitate if the composition is adjusted to a pH above 5, —acid, complexing agent or mixture thereof. The invention also relates to a dental ceramic article obtainable by a process.

The invention relates to a process of selectively treating parts of the surface of a porous dental ceramic comprising the steps of a) providing a composition and a porous dental ceramic having an outer surface, b) applying the composition to only a part of the outer surface of the porous dental ceramic, c) optionally drying the porous dental ceramic, and d) optionally firing the porous dental ceramic, wherein the composition comprises—a liquid being miscible with water, but not being water, —a whitening agent comprising nano-sized metal oxide particles, metal ion containing components or mixtures thereof which precipitate if the composition is adjusted to a pH above 5, —acid, complexing agent or mixture thereof. The invention also relates to a dental ceramic article obtainable by a process.

An appliance fabricated to improve the appearance of a patient's smile includes a plurality of simulated teeth. The interior surfaces of each of the teeth closely fits and conforms to the surface of a patient's real teeth while the outer surfaces of each of the simulated teeth has an ideal surface configuration. The dental appliance provides the patient with the appearance of a perfect set of teeth and an ideal smile without a need to alter the dental structure of the patient's teeth.

An appliance fabricated to improve the appearance of a patient's smile includes a plurality of simulated teeth. The interior surfaces of each of the teeth closely fits and conforms to the surface of a patient's real teeth while the outer surfaces of each of the simulated teeth has an ideal surface configuration. The dental appliance provides the patient with the appearance of a perfect set of teeth and an ideal smile without a need to alter the dental structure of the patient's teeth.

Systems and methods for designing thermoformed removable orthodontic aligners and improving the retention of such aligners to patient teeth are disclosed. The systems generally include a digital scanner that is configured to obtain a digital image of a patient's dentition and a computing environment that is configured to receive a copy of the digital image; create a reference plane relative to one or more teeth featured within the digital image; position a line that runs perpendicular from the reference plane and runs tangential to a height of maximum convexity of each of the one or more teeth; measure an area of undercut between such perpendicular line and an exterior surface of each of the one or more teeth; repeat the foregoing steps at a plurality of points along the perimeter of each of the one or more teeth; and construct a three-dimensional model of an undercut area for each of the one or more teeth.

The present invention provides a method that is for producing a zirconia sintered body and by which a zirconia molded body or a zirconia pre-sintered body is sintered in a short period of time, the zirconia sintered body reproducing an aesthetic requirement and strength of an ideal dental prosthesis at the same levels as those of a zirconia sintered body obtained by general firing. The present invention relates to a method for producing a zirconia sintered body, comprising a step of firing a zirconia molded body or a zirconia pre-sintered body, wherein: the firing step comprises at least three temperature increase steps including a first temperature increase step (H1), a second temperature increase step (H2), and a third temperature increase step (H3); a temperature increase rate in the first temperature increase step (H1) is defined as HR1, a temperature increase rate in the second temperature increase step (H2) is defined as HR2, and a temperature increase rate in the third temperature increase step (H3) is defined as HR3; HR1=50 to 500° C./min, HR2=11 to 300° C./min, HR3=10 to 299° C./min, HR1>HR2, and HR2/HR3>1 are satisfied; starting temperatures in the temperature increase steps are room temperature to 500° C. in H1, 900 to 1250° C. in H2, and 1300 to 1550° C. in H3; and reaching temperatures in the temperature increase steps are 900 to 1250° C. in H1, 1300 to 1550° C. in H2, and 1400 to 1650° C. in H3.

The present invention provides a method that is for producing a zirconia sintered body and by which a zirconia molded body or a zirconia pre-sintered body is sintered in a short period of time, the zirconia sintered body reproducing an aesthetic requirement and strength of an ideal dental prosthesis at the same levels as those of a zirconia sintered body obtained by general firing. The present invention relates to a method for producing a zirconia sintered body, comprising a step of firing a zirconia molded body or a zirconia pre-sintered body, wherein: the firing step comprises at least three temperature increase steps including a first temperature increase step (H1), a second temperature increase step (H2), and a third temperature increase step (H3); a temperature increase rate in the first temperature increase step (H1) is defined as HR1, a temperature increase rate in the second temperature increase step (H2) is defined as HR2, and a temperature increase rate in the third temperature increase step (H3) is defined as HR3; HR1=50 to 500° C./min, HR2=11 to 300° C./min, HR3=10 to 299° C./min, HR1>HR2, and HR2/HR3>1 are satisfied; starting temperatures in the temperature increase steps are room temperature to 500° C. in H1, 900 to 1250° C. in H2, and 1300 to 1550° C. in H3; and reaching temperatures in the temperature increase steps are 900 to 1250° C. in H1, 1300 to 1550° C. in H2, and 1400 to 1650° C. in H3.

The present invention to a method of denture manufacture that incorporates CAM-formed occlusal inserts, crowns, or overlays made of zirconia, resulting in a natural fit, feel, and wear essentially equivalent to the wear properties of natural teeth.