Abstract: The present invention relates to novel mirrors, in particular medical mirrors, preferably dental mirrors, also referred to as mouth mirrors, which have a hole through which dental instruments, in particular root canal instruments or gutta-percha points, can be placed, and to devices comprising a dental mirror according to the invention.

Abstract: A device and process for the surface machining of workpieces with convex surfaces, the device including an abrasive belt, abrasive belt clamping devices, an abrasive belt tensioning device, and clamping tongs device with two clamping arms, one of which is rotatable relative to the other. A section of unused abrasive belt is drawn from a supply roll for the abrasive belt and a corresponding section of used abrasive belt is wound onto a wind-up roll for the abrasive belt so that machining proceeds with a new section of abrasive belt.

Abstract: An apparatus for the surface machining of workpieces with convex surfaces uses a grinding belt (11). Fresh grinding belt (11) is brought to the surface of the workpiece for machining by a belt feed device (28). The belt feed device (28) for conveying the grinding belt (11) has a hydraulic drive (27) or pneumatic drive.

Abstract: An apparatus having a machining tool (52) for machining rollers (40) having a marked curvature and rotating while being machined contains two guiding disks (12,38) and a supporting disk (18) which are pivoted. The guiding disks (12,38) surround roller (40) in a machining position (A) on both sides and symmetrically to a transverse axis (43) running through the center (42) of roller (40). Each guiding disk (12,38) consists of two index disks (46) which eccentrically touch roller (40) by their surface areas (48) which are adapted to roller (40). Supporting disk (18) projects into the gap between index disks (46) and may be slided into a position averted from the machining tool (52).