Abstract: A tensioning screw for orthodontic teeth straightening devices employed to adjust the situation and position of teeth along the curve of the jaw. The screw includes a nut and a threaded shaft that extends through it. An essentially resilient component (11) is disposed between the nut (6) and the shaft (2), at least on one side where the shaft enters or leaves the nut, and rests against the shaft's threads to prevent the shaft from undesired turning with respect to the nut.

Abstract: The invention refers to a device for orthodontic tooth regulation by means of fixed regulating appliances (Edgewise technique). Through such fixed appliances the teeth will be moved under control along a regulating archwire which is ligated to the brackets which are fixed to the teeth. In order to control the forces transmitted to the teeth to be moved and to avoid overload of the periodontal apparatus, it is proposed according to the invention to insert regulating screws along the regulating archwire between fixed parts (such as brackets or tubes) of the regulating appliance, which can be adjusted in their length. The regulating arch is preferably provided partly with a thread, to which regulating nuts can be screwed on. Using such regulating screws as force elements, the force transmitted to the teeth can be measured in a way that the teeth will be moved within a physiological frame.

Abstract: The invention relates to a dental-orthodontic device or instrument comprising an essentially straight handle and a working head which is particularly suited for the precise placement of adhesive brackets on tooth surfaces. Between its handle and its working head the instrument is approximately U-shaped, consequently, when the device is used, the handle is outside the oral cavity of the patient. When positioning the brackets on the teeth, the corners of the mouth and the cheeks of the patient, stabilized by a "lip-retractor", lie in the U-shaped portion of the instrument. In addition, the working head is disposed in the extension of the central axis of the handle. The instrument may also be constructed in such a way that is resembles a pair of tweezers.