LT6669B - An instrument for measure the width of the jaw alveolar cheek wall - Google Patents

Abstract

The present invention relates to an instrument for monitoring changes in jawbone alveolar width following a tooth extraction procedure. The developed instrument is non-invasive and harmless to the patient, accurate, convenient to measure the width of the jaw alveolar cheek wall periodically, in a standardized manner. By direct implantation into the alveolus of the tooth, thanks to the instrument, it is possible to determine the effect of various osteoplastic materials inserted in the space between the dental implant and the alveolar cheek wall, effect to the degree of horizontal resorption of the alveolar cheek wall. Using this instrument does not require the patient to repeat the radiological examination to monitor anatomical changes after dental implantation.

Description

FIELD OF INVENTION

The present invention relates to an instrument for monitoring changes in jaw alveolar widths following a tooth extraction procedure.

TECHNICAL LEVEL DESCRIPTION

Until now, only cone-beam computed tomography examination has been used for this measurement.

Frequent measurement of bone width after various procedures is required to perform research to monitor long-term changes in the maxillary alveolus. Measurements must be standardized in the same position to measure changes in a specific area.

Conical beam CT imaging, which is routinely performed for this purpose, is quite accurate, but detrimental to irradiation. The slider used is inaccurate because it only measures the width of the alveolar cortex and its changes, but cannot reveal changes in the anterior alveolar wall.

EP1922018 describes a distance measuring apparatus for inserting a dental implant. With a distance measuring device for dental implant insertion, proper setting of the drill points is possible without the surgical plate-guide, and the drill points can be appropriately varied when the implant cannot be inserted into the intended part due to alveolar resorption, even if a surgical plate-guide is used.

US2007243498 describes an instrument and method for measuring the minimum distance between two teeth to determine if this distance is sufficient to introduce one or two implants. The instrument is used to check that the distance between the two teeth is the minimum appropriate distance for one or two implants to be inserted and that there is sufficient space in the centers to attach the implant. With this instrument, the placement of the two implants is evenly distributed.

However, these instruments are not suitable for measuring the same location periodically and in a standardized manner.

BRIEF DESCRIPTION OF THE INVENTION

The object of the present invention is to observe the changes in the width of the alveolar cheek wall after jaw extraction and to record them in a standardized manner over time for the same person. After tooth extraction, vertical and horizontal resorption of the alveolar cheek wall occurs. Conventional computed tomography examination of the cone, which is quite accurate but detrimental to the irradiation, is usually performed to determine the degree of horizontal absorption. The developed instrument is non-invasive and non-invasive to the patient, accurate, convenient for measuring the width of the jaw alveolar cheek wall periodically, in a standardized manner. During the immediate implantation into the alveolar tooth extraction, the instrument can determine the effect of various osteoplastic materials placed on the space between the dental implant and the alveolar cheek wall on the degree of resorption of the alveolar cheek wall. With this instrument, the patient does not need to undergo radiological follow-up to observe anatomical changes after dental implantation (which is sometimes prohibited by the Bioethics Commission).

BRIEF DESCRIPTION OF THE DRAWINGS Fig. depicts an instrument for measuring the width of the alveolar cheek wall of the jaw.

DETAILED DESCRIPTION OF THE INVENTION

The device consists of a housing (1) into which a measuring axis (2) is inserted, containing a measuring scale graduated every 0.5 mm and fixed by a screw sleeve (3). The locking axle (4) is inserted into the sleeves (5, 6, 7) during the measurement and in each case locked with a screw for fixing the locking axle (8). The instrument is calibrated with a calibration ruler (9), which is screwed to secure the calibration ruler (10). The instrument is calibrated on the calibration pad (11) by inserting the locking axle (4) into the recess (12) of the locking axle. The calibrated device is inserted into the barrel (13) fixed on an individual plastic guide plate.

Initially, the device is first calibrated. The measuring (2) and locking (4) axes are inserted into the housing (1) of the instrument. The locking axle (4) is fastened with a screw to secure the locking axle (8). The device is then placed on the calibration pad (11) so that the locking shaft (4) engages fully and leans against the locking shaft recess (12). Move the measuring axis (2) to rest on the calibration block (11). Screw the sleeve (4) to lock the measuring axis to prevent it from moving. The calibration ruler (4) is then adjusted to indicate the unit marked 0 on the measuring axis (2). The device is now ready for use.

Prior to the measurement of the anterior wall of the maxillary alveolus, the patient is placed on an individual plate-guide. There are four cavities in the projection of the implant implanted in the plate: the lowest cavity for fixing the cylinder and three cavities for measuring the alveolus. A cylinder of known length (13) is inserted into the lowest cavity so that its end rests on the implant inserter. The cylinder (13) is securely fixed in the composite and from now on will always have a stable fixed reference point (AT). The cylinder (13) is then inserted into the locking axis (4) of the calibrated device, which is fixed in the bushing (5). While holding the device steadily, the measuring axis (2) is pushed down through the first cavity made in the plate-guide, about 3 mm below the alveolar ridge, until the bone is resting. When leaning against the bone, record the digital readout on the measuring axis (2) at the calibration ruler (9). This determines the distance from the AT to the outer surface (IP) of the alveolar cheek wall. The device is then removed from the barrel (13), the locking axle (4) is removed from the bushing (5) by unscrewing the locking shaft screw (8) and inserted into the other bushing (6). The locking axle (4) is locked by tightening the locking axle bolt (8). The instrument is recalibrated as described above and a second measurement is made by inserting the measuring axis (2) up to the bone through the second opening of the guide plate 3 mm above the first opening. After recording the instrument and moving the locking axle (4) to the bushing (7), a third measurement is made in the same manner as in the projection of the third plate-guide aperture. In this way, the IP distance is measured at three points spaced every 3 mm since the thickness of the alveolar wall may vary on the vertical axis. The thickness of the anterior wall (PSS) is calculated using the formula: The dimension of the datum (AT) is the distance from the AT to the outer surface (IP) of the alveolar cheek wall, or PSS = AT - IP.

An objective measurement can be made at any time since the reference point AT recorded on the individual plate-guide will remain unchanged.

Claims (8)

DEFINITION OF INVENTION An instrument for measuring the width of the alveolar wall of the jaw, characterized in that the instrument consists of a housing (1) with a measuring axis (2) having a measuring scale graduated every 0.5 mm and fixed by a screw- jvore (3); a locking axle (4) which is inserted into the sleeve (5, 6, 7) during the measurement and in each case secured by a screw for fixing the locking axle (8); calibration ruler (9) which is fixed by screw (10) 2. An instrument according to claim 1, further comprising a calibration pad (11) having a locking axis recess (12) and a cylinder (13) fixed in the patient's individual plastic guide plate. 3. An instrument according to claim 2, wherein the patient's individual plaque guide has four cavities: the lowest cavity for fixing the barrel and three cavities for measuring the alveolus. 4. An instrument according to claim 1, characterized in that the barrel (13) is fixedly fixed to the composite and is a stable fixed reference point (AT). Method of determining the width of the alveolar wall of the jaw, characterized in that it comprises the following steps: (a) instrument calibration; b) adjusting the outer surface of the anterior wall of the maxillary alveolus by inserting a cylinder (13) of known length into its lowest cavity so that its end rests on the implant guide, j cylinder (13), which is a stable reference point (AT); (4) fixed in the sleeve (5) by pushing the measuring axis (2) down through the first made cavity in the plate-guide about 3 mm below the alveolar crest until the bone is exposed to determine the outer surface (IP) of the alveolar cheek wall; (c) determination of the distance from the reference point (AT) to the external surface of the cheek wall (IP). 6. The method of claim 4, wherein step a) is performed prior to each determination of the outer surface of the alveolar anterior wall. 7. A method according to claim 4, characterized in that step b) is repeated by fixing the locking axis (4) in the bushes (6, 7) respectively. 8. The method of claim 4, wherein the IP distance is determined at three points spaced 3 mm apart.