JP2011000133A - Method of acquiring ecological functional core used for manufacturing crown restoration - Google Patents

Abstract

PROBLEM TO BE SOLVED: To acquire an ecological function core to manufacture a crown restoration having an appropriate shape considering the movement of an antagonist.SOLUTION: The method of acquiring the function core used to manufacture the crown restoration for an abutment tooth by using a computer includes; a process in which a plurality of the shapes of the outermost enclosure of the antagonist when a person for whom the crown restoration is to be manufactured makes biting motions are input to the computer; and a process in which the computer accumulates the input plurality of the shapes of the outermost enclosure, obtains the trace of the outermost enclosure of the antagonist, and obtains the function core by using the obtained trace of the outermost enclosure.

Description

  The present invention relates to a method for obtaining an ecological functional core used in manufacturing a crown restoration. More specifically, the present invention relates to a method for obtaining a functional core that also considers the actual movement of the opposite tooth.

  In dentistry, crown restorations (bridges, crowns, etc.) are used. Then, a tooth model in which the upper and lower dentitions are fixed in a natural meshing positional relationship is created, and the teeth are placed on the abutment tooth formed on a part of the dentition so as not to disturb the positional relationship between the upper and lower dentitions. Methods for designing crown restorations are known. This method does not take into account the positional relationship between the upper and lower dentitions when occlusal. For this reason, the shape had to be adjusted after the crown restoration was manufactured.

  For this reason, a method considering an occlusal movement called check bite or FGP has been proposed. In this method, when the jaw is moved, the movement is recorded by directly biting the wax in the patient's mouth and measured with a measuring instrument. This method takes into account the positional relationship between the upper and lower dentitions during occlusal movement. However, this method has problems such as a shift when the wax is bitten.

  Japanese Laid-Open Patent Publication No. 9-253100 discloses a method for producing a restoration of a dental crown in which a plaster model of a patient's upper and lower jaw dentition is created and the masticatory motion is taken into consideration. In this method, it is disclosed that a dental restoration is reproduced using a dental articulator to produce an accurate crown restoration. In addition, the occlusal movement by the model is a linear one obtained by sweeping between reference points with reference to a virtual reference point, and the actual occlusal movement cannot be appropriately reflected. This makes it impossible to produce a crown restoration that is truly suitable for the patient.

  On the other hand, Japanese Patent Application Laid-Open No. 2006-320369 discloses a method for obtaining a tooth shape using ultrasonic waves and manufacturing a restoration of a crown based on the obtained shape. However, the method for manufacturing a restoration of a crown disclosed in this document does not manufacture a restoration of a crown in consideration of complicated movement of a tooth based on an occlusal movement. For this reason, when the restoration of a crown is manufactured according to the method described in this publication, a sense of incongruity occurs when the restoration is applied.

  In recent years, highly aesthetic crown restorations made of ceramics are known. In particular, crown restorations containing zirconia or yttrium are 3 to 5 times harder than natural teeth. For this reason, patients who use non-optimal crown restorations have the problem that the crown restorations scrape the teeth and cause temporomandibular disorders. For this reason, a method for manufacturing a crown restoration that perfectly captures the patient's occlusal movement was desired.

  Furthermore, when a crown restoration is manufactured considering only the positional relationship between the abutment tooth and the counter tooth as described above, the actual occlusal movement cannot be reproduced. As a result, when a crown restoration was manufactured considering only the positional relationship between the abutment tooth and the counter tooth, wearing the crown restoration would cause a sense of incongruity, and the opposite tooth (existing on the opposite side) Tooth) and its counter teeth.

JP-A-9-253100 JP 2006-320369 A

  Therefore, an object of the present invention is to obtain an ecological functional core for manufacturing a crown restoration having an appropriate shape in consideration of the movement of the paired teeth. Another object of the present invention is to provide a method for designing a crown restoration using the obtained ecological functional core.

  The present invention is based on the knowledge that an appropriate restoration of the crown can be obtained by obtaining not only the shape information of the paired teeth but also information on the actual movement of the paired teeth. Furthermore, the present invention is based on the knowledge that the trajectory of the opposing teeth in the occlusal movement can be accurately grasped by continuously measuring the dentition using ultrasonic waves.

  Furthermore, the present invention is based on the knowledge that the impression of the ecological functional core can be obtained with high accuracy by using the moire phenomenon when observing the movement of the paired teeth using ultrasonic waves.

  The first aspect of the present invention relates to a method for obtaining an ecological functional core used for manufacturing a crown restoration on an abutment tooth using a computer. In this method, a plurality of outermost contour shapes of the opposing teeth when a person who is to produce a restoration of the crown performs an occlusal movement are input to the computer. Then, the computer accumulates a plurality of input outermost contour shapes, obtains the outermost locus of the opposite teeth, and obtains an ecological functional core using the obtained outermost locus. In this way, since the ecological functional core is obtained by accumulating the locus of the paired teeth, this method can obtain an appropriate functional core. Here, the shape of the outermost contour includes the shape of the outermost contour when performing mandibular anterior movement, mandibular lateral movement, and mandibular backward movement, and preferably reflects the maximum movable range of the mandible.

  In a preferred embodiment of the first aspect of the present invention, the occlusal movement includes a mandibular anterior movement, a mandibular lateral movement, and a mandibular posterior movement. Thus, by taking into account any counter tooth movement, this method can determine an appropriate functional core.

  In a preferred embodiment of the first aspect of the present invention, the trajectory of the paired teeth is measured using an ultrasonic shape analysis apparatus including an ultrasonic probe. By finding the trajectory of the counter teeth using an ultrasonic shape analyzer, this method can appropriately grasp not only the overview but also the trajectory on the back side of the counter teeth that is not visible from the surface and the trajectory on the opposite side. Become.

  In another preferred embodiment of the first aspect of the present invention, the trajectory of the counter teeth is measured using an ultrasonic shape analyzer, and the ultrasonic shape analyzer is the first super The acoustic probe includes a second ultrasonic probe having a frequency different from that of the first ultrasonic probe. When the shape of a pair of teeth is obtained using one ultrasonic probe, the accuracy is generally on the order of several micrometers or less. However, in order to obtain an optimal crown restoration, an accuracy on the order of micrometers is desirable. Thus, by using two ultrasonic probes, this method can improve the measurement accuracy by utilizing the moire phenomenon.

  The second aspect of the present invention relates to a method of designing a crown restoration used for a certain abutment tooth using a computer. In this method, information about the abutment tooth and the shape of the abutment tooth is input to the computer. In addition, a plurality of outermost contour shapes of the opposing teeth when a person who manufactures the restoration of the crown performs an occlusal movement are input to the computer. Then, the computer accumulates a plurality of input outermost contour shapes, obtains the outermost locus of the opposite teeth, and obtains an ecological functional core using the obtained outermost locus. After that, the computer uses the abutment tooth, the shape of the abutment tooth, and the ecological functional core to determine the shape of the crown restoration provided on the abutment tooth. The shape of the crown restoration is that which comes into contact with the functional core when the restoration is attached to the abutment tooth. This second aspect can include any aspect of the first aspect described above.

  According to the present invention, since the ecological functional core is acquired by considering a plurality of the trajectories of the paired teeth at the time of the occlusal movement, the restoration of the crown having an appropriate shape considering the movement of the paired teeth is manufactured. You can get a functional core for. In addition, this ecological functional core reflects not only the abutment tooth and its counter teeth, but also the occlusal movement on the opposite side. Therefore, by using the ecological functional core of the present invention, a crown restoration that perfectly fits the patient can be produced.

FIG. 1 is a diagram illustrating an example of an abutment tooth on which a crown restoration is provided and a functional core. FIG. 2 is a diagram for explaining a region including an abutment tooth and a counter tooth. FIG. 3A is a diagram for explaining three-dimensional information of a dentition continuously stored with a certain occlusal movement. FIG. 3B shows a trajectory of the outermost contour of the paired teeth accompanying a certain occlusal movement. FIG. 4A is a diagram for explaining three-dimensional information of a dentition continuously stored with an occlusal movement different from that in FIG. 3A. FIG. 4B shows a trajectory of the outermost contour of the paired teeth accompanying this occlusal movement. FIG. 5 is a diagram illustrating a state where the outermost trajectories of the obtained counter teeth are superimposed. FIG. 6 is a diagram showing a design example of a crown restoration. FIG. 7 is a conceptual diagram for explaining teeth and directions. FIG. 7A is a perspective view showing a pair of teeth when in the central occlusal position, and FIG. 7B is a view when the pair of teeth when in the central occlusal position is viewed from an angle different from FIG. 7A. is there. FIG. 8 is a conceptual diagram showing the movement of the occlusal position and the occlusal movement. FIG. 9 is a diagram for explaining the locus formed by the occlusal movement of the teeth shown in FIG. 7 and the functional core. FIG. 9A is a diagram illustrating tooth movement when the tooth of FIG. FIG. 9B is a diagram illustrating a tooth locus and a functional core as seen from the X-axis direction. FIG. 9C is a diagram illustrating a state of the functional core viewed from the X-axis direction. FIG. 9D is a diagram illustrating tooth movement when the tooth of FIG. FIG. 9E is a diagram illustrating a tooth locus and a functional core as seen from the Y-axis direction. FIG. 9F is a diagram illustrating the functional core as viewed from the Y-axis direction.

  Hereinafter, embodiments of the present invention will be described based on examples. The present invention is not limited to the following embodiments, and those skilled in the art can appropriately modify the embodiments described below within the obvious range, and such embodiments are also included in the present invention.

  The first aspect of the present invention relates to a method for obtaining an ecological functional core used for manufacturing a crown restoration on an abutment tooth using a computer. A plurality of outermost contour shapes of the opposing teeth when a person who manufactures the restoration of the crown performs an occlusal movement are input to the computer. Then, the computer accumulates a plurality of input outermost contour shapes, obtains the outermost locus of the opposite teeth, and obtains an ecological functional core using the obtained outermost locus. Here, the counter teeth are teeth (one or more) facing the abutment tooth on which the crown restoration is provided. Examples of crown restorations, inlays that are packed into the teeth to restore part of the teeth, crowns that are placed on the teeth, bridges that are connected to restore the occlusion of several missing teeth, and local dentures .

  The computer includes a control unit, a storage unit, a calculation unit, and an input / output unit. Each element can exchange information via a bus or the like. When predetermined information is input from the input unit, the control unit reads the control program from the main memory stored in the storage unit. And a control part performs various operation | movement according to a control program. For example, the control unit reads predetermined information from the storage unit and performs calculation processing in the calculation unit. Then, the control unit instructs the storage unit to store the obtained calculation processing result.

  FIG. 1 is a diagram illustrating an example of an abutment tooth on which a crown restoration is provided and a functional core. The functional core 1 means a region in which the outer part of the paired teeth can move when various occlusal movements are performed (for example, the case where the functional core is applied to an anterior porcelain jacket crown (28th Kyushu) (See General Meeting of Dental Society and Academic Lectures) (pages 181 and 182). Conventional virtual functional cores have been required by creating jaw models, performing occlusal movements, and collecting some positional information. For this reason, the functional core itself was not appropriate. In the present invention, since a plurality of outermost trajectories of the opposing teeth are accumulated when the occlusal movement is performed, an appropriate mechanism core can be obtained. That is, the functional core of the present invention is not a virtual one obtained using a conventional model. The functional core of the present invention is obtained based on observation of the patient's actual occlusal movement and observation of the patient's ecology. For this reason, in this specification, in order to distinguish the conventional virtual functional core and the functional core of this invention, the latter is also called an ecological functional core.

  The shape and locus of the pair of teeth can be measured using an ultrasonic shape analyzer including an ultrasonic probe. Teeth include enamel, dentin and pulp. The teeth are irradiated with ultrasonic waves from an ultrasonic shape analyzer and the ultrasonic waves reflected from the teeth are measured. Then, the intensity of the reflected ultrasonic wave differs depending on the material of the reflected part. If this property is used, the outline of a tooth can be obtained using an ultrasonic shape analysis apparatus. At this time, not only the outline of the tooth but also the internal structure of the tooth (dentin part and pulp part) can be obtained. Furthermore, when teeth are measured using an ultrasonic shape analyzer, not only abutment teeth and counter teeth, but also teeth on opposite sides and counter teeth can be measured together. As described above, by using the ultrasonic shape analysis apparatus, it is possible to appropriately grasp the movement of the teeth existing on the opposite side surface.

  In the present invention, for example, a region including an abutment tooth and a pair of teeth when the mandibular anterior movement, the mandibular lateral movement, and the posterior movement of the mandible are continuously measured using an ultrasonic shape analysis apparatus.

  The reflected wave data of the ultrasonic wave of the region including the abutment tooth and the paired tooth taken by the ultrasonic shape analyzer is input to the computer. This reflected wave data is data related to the shape of the outermost contour of the pair of teeth. Then, the computer temporarily stores the reception time and reception intensity of the received reflected wave. The ultrasonic shape analyzer sweeps the measurement area. The computer temporarily stores the reception time and reception intensity of the reflected wave in the swept area. By using this collected information, the computer can obtain three-dimensional information of a region including the abutment tooth and the counter tooth at a certain timing. The computer temporarily stores the obtained three-dimensional information. On the other hand, information related to the three-dimensional shape of the abutment tooth is also stored in the computer.

  FIG. 2 is a diagram for explaining a region including an abutment tooth and a counter tooth. In FIG. 2, this area is represented two-dimensionally for simplicity. Actually, the computer grasps this area three-dimensionally. In FIG. 2, reference numerals 12 a to 12 c indicate counter teeth. Reference numerals 13a and 13b denote teeth adjacent to the abutment teeth.

  The ultrasonic shape analyzer and the computer continuously perform the above measurement and analysis. Then, the computer continuously obtains the three-dimensional information of the dentition including the abutment teeth and the paired teeth accompanying a certain occlusal movement. The computer stores this continuous three-dimensional information.

  And a computer reads the information regarding the three-dimensional shape of an abutment tooth. Then, the computer uses the 3D shape of the abutment tooth to extract the abutment tooth portion from the 3D information of the dentition including the abutment tooth and the counter tooth. Then, the computer obtains the three-dimensional information of the counter teeth based on the extracted abutment tooth portion. In this way, the computer continuously obtains and stores the three-dimensional information of the counter teeth. The computer uses the stored three-dimensional information of the paired teeth to obtain the outermost contour of the paired teeth. The computer continuously integrates the shape of the outermost contour of the counter teeth based on the abutment tooth portion. More specifically, the computer stores the outermost contours of the opposing teeth accumulated up to a certain time. When the shape of the outermost contour of the next pair of teeth is input, the outermost contour of the pair of teeth accumulated until a certain time is read out. Then, it is determined whether or not each part of the newly input outermost shape is included in the outermost contour of the accumulated counter teeth. If the part with the newly entered outermost contour shape is not included in the outermost contour of the paired teeth, the new portion is included in the outermost contour of the accumulated paired teeth. It memorize | stores as the outermost outline of the accumulated counter teeth. In this way, the trajectory of the outermost contour of the opposing teeth accompanying a certain occlusal movement can be obtained by the computer.

  FIG. 3A is a diagram for explaining three-dimensional information of a dentition continuously stored with a certain occlusal movement. Reference numeral 14 in the figure indicates a displaced counter tooth. FIG. 3B shows a trajectory of the outermost contour of the paired teeth accompanying a certain occlusal movement. Reference numeral 15 in the figure indicates the locus of the outermost contour of the paired teeth accompanying a certain occlusal movement.

  In a preferred embodiment of the first aspect of the present invention, the occlusal movement includes a mandibular anterior movement, a mandibular lateral movement, and a mandibular posterior movement. In this way, an appropriate ecological functional core can be obtained by taking into account any movement of the teeth. In other words, during anterior mandibular movement, an ultrasonic shape analyzer is used to continuously measure the region including the abutment tooth and the counter tooth. Then, based on the process described above, the trajectory of the outermost contour of the opposing teeth during mandibular anterior movement can be obtained. In the same manner, the trajectory of the outermost contour of the opposing teeth during the lateral movement of the lower jaw and the backward movement of the lower jaw can be obtained. By accumulating these trajectories, it is possible to appropriately obtain trajectories in which the counter teeth can move during various occlusal movements. The computer obtains the ecological functional core using the outermost locus of the paired teeth. The method for obtaining the ecological functional core is the same as the method for obtaining the locus of the outermost contour of the above-mentioned counter teeth.

  FIG. 4A is a diagram for explaining three-dimensional information of a dentition continuously stored with an occlusal movement different from that in FIG. 3A. Reference numeral 16 in the figure indicates a displaced counter tooth. FIG. 4B shows a trajectory of the outermost contour of the paired teeth accompanying this occlusal movement. Reference numeral 17 in the figure indicates the locus of the outermost contour of the opposing teeth accompanying this occlusal movement.

  FIG. 5 is a diagram illustrating a state where the outermost trajectories of the obtained counter teeth are superimposed. The mechanism core 1 shown in FIG. 1 can be obtained by accumulating the trajectories 15 and 17 of these outermost portions.

  In a preferred embodiment of the present invention, the computer stores the shape pattern of the crown restoration. And the space which exists between the mechanism core 1 calculated | required as mentioned above and the anchor tooth 11 is calculated | required. Then, the shape pattern of the restoration of the crown is read out using the obtained space information. In this way, the computer can determine the shape of the crown restoration that contacts the ecological functional core when attached to the abutment tooth.

  Conventional crown restorations have a sense of incongruity because they do not fit perfectly when the crown restoration is attached to the abutment. However, in the present invention, an ecological function core that reflects the actual occlusal movement is obtained, and the shape of the dental restoration is obtained using the obtained ecological function core. This makes it possible to design a crown restoration that fits perfectly and does not feel uncomfortable when worn.

  FIG. 6 is a diagram showing a design example of a crown restoration. As shown in FIG. 6, a crown restoration 20 is designed on the abutment tooth 11. The crown restoration 20 is provided so as to fit between the mechanism core 1 and the abutment tooth 11. For this reason, the crown restoration 20 comes into contact with the ecological functional core when it is attached to the base tooth. That is, when the crown restoration is actually manufactured based on the shape data of the crown restoration 20, the obtained crown restoration has an appropriate shape in contact with the counter tooth.

  In another preferred embodiment of the first aspect of the present invention, the trajectory of the counter teeth is measured using an ultrasonic shape analyzer, and the ultrasonic shape analyzer is the first super The acoustic probe includes a second ultrasonic probe having a frequency different from that of the first ultrasonic probe. When the shape of a pair of teeth is obtained using one ultrasonic probe, the accuracy is generally on the order of several micrometers or less. However, in order to obtain an optimal crown restoration, an accuracy on the order of micrometers is desirable. Thus, by using two ultrasonic probes, the measurement accuracy can be improved by utilizing the moire phenomenon.

  A shape analysis method using a moire phenomenon by ultrasonic waves is disclosed in, for example, Japanese Patent Laid-Open No. 2006-029991. In this aspect, the moire phenomenon can be observed with higher accuracy by causing interference using two or more types of ultrasonic probes.

  In the present invention, the ultrasonic shape analyzer preferably has a plurality of probes. For example, it is preferable to mount three or more probes on the upper dentition and the lower dentition. When three probes are attached, the attachment range of the three probes attached to each jaw is the front teeth and left and right molars ((1) from the right canine to the left canine, (2) the right (From the first premolar to the third molar, (3) from the left first premolar to the third molar). The probe may be attached to the buccal surface of the dentition, the gingiva on the buccal surface of the dentition, or may be attached to the artificial tooth or artificial gingiva part of the denture. Furthermore, a probe may be mounted outside the oral cavity so as to be in the position range. When a plurality of probes are used, it is preferable that the frequency of the ultrasonic wave transmitted from each probe is different. In the present invention, the probe is preferably an array probe having a plurality of transducers or a matrix array probe. The plurality of transducers included in the probe can change the wavelength for each transducer. And the probe which has a some vibrator | oscillator can adjust the angle and timing which transmit an ultrasonic wave for every vibrator | oscillator. Therefore, in the present invention, the array transducer or the matrix array probe is preferable because it can acquire data such as the shape of the teeth or dentition without moving the probe. Since array transducers or matrix array transducers are known, those skilled in the art can appropriately select and use them.

  When three probes are attached to the upper jaw and the lower jaw, during the occlusal movement, an ultrasonic wave is transmitted toward the tooth from which information is obtained from the probe, and the reflected waves reflected thereafter are detected. Receive at the child. The reflected wave from the paired teeth also changes depending on the distance from the probe to the paired teeth. In the present invention, the position information of the counter teeth can be obtained by using the data of the intensity of the reflected wave and the time required until the reflected wave is received. During the occlusal movement, the distance between the paired teeth and the probe on the opposite jaw is changed. As the distance between the pair of teeth and the probe increases, the time required to receive the reflected wave increases. Therefore, for example, when in the central occlusal position, the position information of the tooth during the occlusal movement can be acquired based on the time until the reflected wave from the abutment tooth is received.

  FIG. 7 is a conceptual diagram for explaining teeth and directions. FIG. 7A is a perspective view showing a pair of teeth when in the central occlusal position, and FIG. 7B is a view when the pair of teeth when in the central occlusal position is viewed from an angle different from FIG. 7A. is there. In FIG. 7, the lateral movement direction of the teeth is the X axis, the forward and backward movement directions are the Y axis, and the opening and closing movement direction is the Z axis. FIG. 7 assumes the right tooth. The positive direction of the X axis indicates the lingual direction, and the negative direction of the X axis indicates the cheek side. The positive direction of the Z axis indicates the upper jaw side, and the negative direction of the Z axis indicates the lower jaw side. An arbitrary point (such as a fissure on the occlusal surface) on the opposing teeth when the upper dentition and the lower dentition are in the central occlusal position is set to Z = 0. Thereby, during occlusal movement, tooth position information can be represented by three-dimensional data (X value, Y value, Z value).

  FIG. 8 is a conceptual diagram showing the movement of the occlusal position and the occlusal movement. In FIG. 8, point i indicates the central occlusal position, point ii indicates the foremost occlusal position, point iii indicates the last occlusal position, point iv indicates the rightmost lateral occlusal position, and point v indicates the leftmost occlusal position. Indicates lateral occlusal position. Based on FIG. 8, the movement of the teeth during the occlusal movement of the teeth will be described. The tooth movement path in the lateral occlusal movement is a path from the left most lateral occlusal position (v) to the central occlusal position (i) and from the central occlusal position (i) to the right most lateral occlusal position (iv). The tooth movement path in the forward occlusal movement is a path from the central occlusal position (i) to the foremost occlusal position (ii). The tooth movement path in the backward occlusal movement is a path from the central occlusal position (i) to the last occlusal position (iii). In addition to the above, in the actual occlusal movement, from the foremost occlusal position (ii) to the rightmost occlusal position (iv), from the foremost occlusal position (ii) to the leftmost lateral occlusal position (v), the last There are various routes such as a route from the right occlusal position (iii) to the right most lateral occlusal position (iv) and a route from the last occlusal position (iii) to the left most lateral occlusal position (v). During the occlusal movement, the teeth move while sliding within the range connecting the above paths with lines. This movement is not linear, as explained earlier. Therefore, accurate tooth movement cannot be reproduced using a model.

  FIG. 9 is a diagram for explaining the locus formed by the occlusal movement of the teeth shown in FIG. 7 and the functional core. FIG. 9A is a diagram illustrating tooth movement when the tooth of FIG. FIG. 9B is a diagram illustrating a tooth locus and a functional core as seen from the X-axis direction. FIG. 9C is a diagram illustrating a state of the functional core viewed from the X-axis direction. FIG. 9D is a diagram illustrating tooth movement when the tooth of FIG. FIG. 9E is a diagram illustrating a tooth locus and a functional core as seen from the Y-axis direction. FIG. 9F is a diagram illustrating the functional core as viewed from the Y-axis direction. As shown in FIG. 9, by connecting the contours of the opposing teeth during various occlusal movements, the trajectory of the opposing teeth can be grasped, and thereby the functional core can be acquired. Since any point on the paired teeth moves in a complicated manner along the movement path as shown in FIG. 8, the movement of the paired teeth is obtained by accumulating the paired tooth locus information based on the position information. It is possible to acquire a practical functional core considering the road.

  In addition, it is preferable that the computer of this invention is connected with a cutting device, and it can manufacture a crown restoration using the data regarding the obtained crown restoration. Prosthetic restorations are manufactured using, for example, resin, porcelain, ceramics, or ceramics with zirconia or yttrium added to metal materials such as gold, silver, stainless steel, cobalt chrome, nickel chrome, and titanium. it can. The ecological functional core of the present invention is designed in consideration of the functional movement path of the paired teeth. Thus, crown restorations manufactured based on the ecological functional core of the present invention are compatible with the target site and do not impair the correct chewing cycle. Therefore, according to the present invention, it is not necessary to adjust the crown restoration before attaching the crown restoration to the target site, and the convenience is greatly enhanced.

  The present invention can be used in the field of the dental equipment industry.

1 Ecological functional core 11 Abutment tooth

Claims (5)

A method for obtaining a functional core used for manufacturing a crown restoration on an abutment tooth using a computer,
A plurality of shapes of the outermost contours of the opposing teeth when a person who manufactures the crown restoration performs an occlusal movement, a step of being input to the computer;
The computer accumulates the plurality of input outermost contour shapes, obtains the outermost trajectory of the opposing teeth, and obtains a functional core using the obtained outermost trajectory.
Method. The occlusal movement includes anterior jaw movement, lateral jaw movement, and posterior jaw movement,
The method of claim 1. The locus of the counter teeth is
It was measured using an ultrasonic shape analyzer including an ultrasonic probe.
The method of claim 1. The locus of the counter teeth is measured using an ultrasonic shape analyzer,
The ultrasonic shape analysis apparatus includes a first ultrasonic probe and a second ultrasonic probe having a frequency different from that of the first ultrasonic probe.
The method of claim 1. A method of designing a crown restoration to be used for an abutment tooth using a computer,
Said method is:
Inputting to the computer the abutment tooth and the shape of the abutment tooth;
A plurality of shapes of outermost contours of the opposing teeth when a person who manufactures the crown restoration performs an occlusal movement, and a step of inputting the shape to the computer;
A step of accumulating the inputted outermost contours to obtain a trajectory of the outermost contour of the mating teeth, obtaining a functional core using the obtained trajectory of the outermost contour; and the abutment tooth Using the shape of the abutment tooth and the functional core to determine the shape of the restoration of the crown provided on the abutment tooth;
Including
The shape of the crown restoration is in contact with the functional core when the crown restoration is attached to the abutment tooth.
Method.

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