Abstract: A CT scanning apparatus in accordance with the present invention comprises an image pickup system having an X-ray source being rotated around an object and a two-dimensional X-ray image pickup portion disposed opposite to the X-ray source with the object therebetween and being rotated, and is configured to rotate the image pickup system so as to radiograph three-dimensional areas inside the object, wherein a substance capable of being detected as an X-ray image is used as a position marker, and the position marker is disposed so as to be positioned in the image pickup view of the image pickup system during the rotation of the image pickup system and radiographed together with the object. In an ideal case, the image of the position marker in the two-dimensional X-ray image obtained as described above moves in a sine curve. Therefore, a correction amount for each X-ray image is calculated from the difference between the actual position in the X-ray image and the ideal position changing in the sine curve.

Abstract: The panoramic radiographic apparatus of the present invention has a cassette holder capable of accommodating both a conventional film cassette and a digital sensor cassette loaded with an electric X-ray image detector, one at a time, in a rotary arm, wherein when a film cassette is mounted, the cassette holder is mechanically moved in accordance with the rotation of the rotary arm so as to carry out panoramic radiographing, and when a digital sensor cassette is mounted, without moving the cassette holder, the electric X-ray image detector is driven by supplying control signals corresponding to the rotation of the rotary arm to the digital sensor cassette to obtain image signals required for generating a panoramic X-ray image. Therefore, both the film cassette and the digital sensor cassette can easily be mounted, one at a time, whereby required panoramic X-ray images can be obtained by fully using the features of each type of cassette.

Abstract: The panoramic radiographic apparatus of the present invention has a cassette holder capable of accommodating both a conventional film cassette and a digital sensor cassette loaded with an electric X-ray image detector, one at a time, in a rotary arm, wherein when a film cassette is mounted, the cassette holder is mechanically moved in accordance with the rotation of the rotary arm so as to carry out panoramic radiographing, and when a digital sensor cassette is mounted, without moving the cassette holder, the electric X-ray image detector is driven by supplying control signals corresponding to the rotation of the rotary arm to the digital sensor cassette to obtain image signals required for generating a panoramic X-ray image. Therefore, both the film cassette and the digital sensor cassette can easily be mounted, one at a time, whereby required panoramic X-ray images can be obtained by fully using the features of each type of cassette.

Abstract: The periodontal pocket measurement apparatus of the present invention comprises a main handpiece unit provided with a cover member for covering the front end portion thereof, an operation member mounted at the front end of the cover member and being slidable in the longitudinal direction of the cover member, a flexible sleeve attached to the operation member and projecting from the front end of the cover member, and a probe attached to the cover member, passing through the sleeve and being exposable at its tip from the tip of the sleeve, being characterized in that the main handpiece unit is provided with energizing means for pushing a movable portion including the operation member and the sleeve toward the front end.

Abstract: A motor controller for a dental handpiece comprising a torque detection means for detecting the load torque applied to a cutting tool, and a control means for stopping a cutting tool drive motor, reducing the rotation speed of the motor or temporarily reversing the motor when the detected load torque has reached a preset reference torque. With this controller, a cutting tool such as a relatively slender file for root canal formation can be prevented from breaking. In addition, the operability of the handpiece can be improved, and operation such as root canal formation can be conducted easily.

Abstract: A dental treatment apparatus with a root canal length measurement function comprising a cordless handpiece equipped with at least a cutting tool drive motor, a root canal length measurement circuit and a power supply battery, and a charger equipped with at least a charge circuit for charging the power supply battery. With this structure, the handpiece can be operated as desired without interference with any tube since no tube is necessary to connect the handpiece to a main control unit, thereby capable of providing an easy-to-use treatment apparatus. By charging the power supply battery for the handpiece using the charger, the battery can be used repeatedly.

Abstract: The present invention discloses a handpiece having a root canal length measurement function, wherein a signal circuit, which is specifically provided for sending measurement signals from a root canal length measurement circuit to a measurement probe mounted on a head provided at the tip of the handpiece, is incorporated in the handpiece, and the signal circuit is electrically connected to the measurement probe via a contact piece in the vicinity of the measurement probe. Therefore, it is not necessary to connect the signal circuit for measurement by way of the outside of the handpiece. In addition, this structure improves the operability of the handpiece because there is no lead wire for connection. Furthermore, this structure eliminates the troublesome task of externally connecting lead wires to the head of the handpiece, which would otherwise be required at each treatment time.

Abstract: In a laser surgical unit having a contact laser probe (1), a hydroxyl group (13) is included in the contact laser probe so that a laser beam is partially absorbed by the hydroxyl group (13) to heat the contact laser probe (1) for transmission to living tissue. Consequently, a coagulation layer is formed in the living tissue along with vaporization and incision. At least a part of the contact laser probe (1) is made of a material which contains the hydroxyl group (13) generally in an amount of between 0.5 and 10 ppm. Alternatively, the hydroxyl group (13) may be included only in a portion adjacent to a surface of a tip portion of the probe (1). As a further alternative, a coating film containing the hydroxyl group (13) may be attached to the tip of the contact laser probe (1). The laser beam preferably has a wavelength between 1.5 and 15 .mu.m. For example, use is made of an Er:YAG laser beam a Ho:YAG laser beam, or a CO.sub.2 laser beam.

Abstract: A medical X-ray image processing apparatus, comprising an X-ray sensor which converts an image of X-rays penetrated an object into an electric signal using a solid-state image sensor and a data processor which processes the electric signal to generate an electric image signal corresponding to the X-ray image, compares the data of each picture element derived from the above-mentioned solid-state image sensor with the data of picture elements being adjacent to the picture element and present within a certain region, and corrects the data of the picture element referring to the data of the above-mentioned adjacent picture elements only when the data of the picture element is exceptionally different from the data of the adjacent picture elements by a predetermined reference value or more.

Abstract: A planigraphic X-ray apparatus comprising a rotation mechanism for rotating a support member which supports an X-ray generator and an X-ray detection surface to rotate the X-ray generator and the X-ray detection surface around a subject, a position adjustment mechanism for setting the position of the rotation center of the support member rotated by the rotation mechanism and a linear movement means for moving the support member in the direction approximately perpendicular to the direction of the X-ray irradiated from the X-ray generator, whereby the X-ray detection surface is driven in the direction opposite to the movement of the linear movement means and the X-ray generator is rotated toward the X-ray detection surface in synchronization with the movement of the linear movement means.

Abstract: A medical X-ray tomographing apparatus, wherein the output end surfaces of a plurality of optical fiber bundles are optically coupled to the image pickup surfaces of vertically long solid-state image pickup devices, such as one-dimensional image sensors, and the input end surfaces of a plurality of the optical fiber bundles having a vertically long cross-sectional shape being identical to that of the output end surfaces thereof are optically coupled individually to a plurality of vertically long divisions obtained by dividing the fluorescent surface of a scintillator in the width direction thereof. With this apparatus, it is not necessary to significantly contract the size of the image on the fluorescent surface, thereby remarkably reducing the number of the solid-state image pickup devices and the number of the divisions of the fluorescent surface.

Abstract: A medical laser treatment device comprising a laser generation source and a laser handpiece which comprises a light-guiding fiber used to guide a laser beam irradiated from the laser generation source, a probe for guiding the laser beam having been guided by the fiber to an object to be irradiated, at least two independent air supply passages and at least one water supply passage, the laser handpiece being adapted such that the emission end of the light-guiding fiber is airtightly isolated from the incident end of the probe via a light-guiding shield plate to make the internal section of the light-guiding fiber airtight, to cool the emission end of the light-guiding fiber using dry gas supplied from the first air supply passage and to cool the incident end of the probe using gas supplied from the second air supply passage, and being also arranged such that water supplied from the water supply passage is blown out from the peripheral section of the leading end of the probe, thereby preventing the emission end

Abstract: A rotational tomographic X-ray apparatus is disclosed as having an X-ray detection surface disposed parallel to a planigraphic plane selected as a subject to be photographed, and comprising a mechanism for linearly moving the X-ray generator and the X-ray detection surface of the apparatus in relatively opposite directions parallel to the planigraphic plane with the head of a patient positioned therebetween, and for controlling the irradiation direction of X-rays so that the irradiated X-rays always pass the same specific region in the planigraphic plane and are incident on the X-ray detection surface in synchronization with the linear movement. With this apparatus, clear planigraphic photographing with no distortion is possible and the magnifying ratios of X-ray images can be changed easily.

Abstract: In a laser surgical unit having a contact laser probe (1), a hydroxyl group (13) is included in the contact laser probe so that a laser beam is partially absorbed by the hydroxyl group (13) to heat the contact laser probe (1) for transmission to living tissue. Consequently, a coagulation layer is formed in the living tissue along with vaporization and incision. At least a part of the contact laser probe (1) is made of a material which contains the hydroxyl group (13) generally in an amount of between 0.5 and 10 ppm. Alternatively, the hydroxyl group (13) may be included only in a portion adjacent to a surface of a tip portion of the probe (1). As a further alternative, a coating film containing the hydroxyl group (13) may be attached to the tip of the contact laser probe (1). The laser beam preferably has a wavelength between 1.5 and 15 .mu.m. For example, use is made of an Er:YAG laser beam, a Ho:YAG laser beam, or a CO.sub.2 laser beam.

Abstract: A medical X-ray image detecting device arranged such that an X-ray image sensor comprising an x-ray fluorescent element, a solid-state image pickup device and a plurality of optical fiber bundles for optically connecting the fluorescent surface of the X-ray fluorescent element to the image pickup surface of the image pickup device, is housed in an outer casing, the medical image detecting device being characterized in that it further comprises an X-ray intensity detecting element disposed in the casing adjacent to the X-ray fluorescent element. Clear X-ray images with a constant blackening degree can be obtained by controlling X-ray radiation time using the X-ray dose calculated by integrating the X-ray intensity output from the X-ray intensity detecting element with respect to X-ray exposure time.

Abstract: A dental handpiece holder adapted such that the length of the handpiece holder for holding and accommodating a dental handpiece is shortened in the axial direction, whereby the main unit of the handpiece can be attached to and detached from the joint section of the handpiece for the purpose of replacement with one hand of an operator. Also a dental treatment assembly by use of the holder.The handpiece holder comprising a gutter-shaped receiving seat, first and second grip sections extending from both side fringes of the receiving seat, contact sections formed at the leading ends of the first and second grip sections respectively and an engagement groove or projection extending across the contact sections or the peripheral areas thereof in the internal circumferential direction of the grip sections.