JP2000279427A - Dental prosthesis base material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dental prosthesis base material by which a prosthesis such as a veneer crown is easily and inexpensively produced. SOLUTION: An artificial front surface 32 corresponding to the front surface (the front surface side of an anterior tooth) is formed at the front side of a prosthesis base material 3 to be the original form of the veneer crown. The state of the surface 32 is previously formed to be close to the one peculiar to a human tooth, that is, the transparent, glossy and white one. Then the whole part of the surface 32 except a part or the whole of it is worked by cutting or grinding so that the desired shape veneer crown is finished. Hemi- spherical index parts 33 and 33 are arranged at the rear side of the base material 3 so that positioning is executed by the parts 33 in the case of a work by cutting or grinding.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dental prosthesis material (hereinafter simply referred to as "prosthesis") which is a prototype of a dental prosthesis (hereinafter simply referred to as "prosthesis") for prosthesis of a missing portion of human teeth. In particular, the present invention relates to a prosthetic material suitable for prosthetic surface (front or cheek side) portions such as front teeth and canines.

[0002]

2. Description of the Related Art As a dental treatment technique for prosthetic treatment of a tooth surface portion as described above, a technique generally called a Porcelain Laminate Veneer method is conventionally known. The procedure is as follows.

[0003] First, in a dental clinic, the surface of the affected tooth is thinly cut, for example, to a thickness of about 0.5 mm, and the impression is taken. Next, a plaster model of the affected tooth is created based on the impression. Then, at a dental clinic or a dental laboratory, a paste-like porcelain material (Porcelain) is formed on the surface of a portion corresponding to the above-mentioned cut and removed portion (strictly, the remaining portion after the cut and removed) of the refractory model reproduced from the plaster model. ) Is applied and baked, and by repeating this porcelain application and firing operation, a prosthesis having a small thickness, that is, a so-called veneer crown (Veneer C) is used in place of the cut and removed portion of the affected tooth.
rown). And this veneer crown,
At the dental clinic, a series of prosthetic operations are completed by bonding to the cut and removed portion of the affected tooth.

[0004] The reason for repeating the application and firing operations of the porcelain as described above is to bring the surface condition of the veneer crown closer to a state unique to human teeth, transparent and shiny white. . That is, a plurality of different types of porcelain materials are sequentially applied and fired, so that a plurality of porcelain layers having different shapes, transparency, and color and luster are laminated. In this way, it is possible to bring out a form, transparency and glossy white state that is close to the surface state unique to human teeth. This is very important in the present porcelain laminate veneer method whose main purpose is to improve the aesthetics of the teeth.

[0005]

However, as described above, according to the conventional porcelain laminate veneer method, it is necessary to repeatedly apply and bake the porcelain, so that one veneer laminate veneer is used. There is a problem that it is very troublesome to manufacture the crown and the cost is high. In addition, since the quality and productivity of the product largely depend on the skill of the dentist or dental technician who performs the work, there is also a problem that products of a certain quality cannot be efficiently produced.

In addition to the porcelain laminate veneer method, there is also a technique of forming a veneer crown by cutting a solid material having a predetermined size, for example. However, according to this technique, a portion corresponding to the surface portion of the tooth is also formed by cutting or grinding, so that a unique form, transparency and color luster of a human tooth cannot be produced at all. .

Accordingly, the present invention provides a prosthesis material which can produce a prosthesis such as a veneer crown having a shape, transparency and color luster similar to the surface condition of human teeth more easily and at lower cost than before. The purpose is to do.

[0008]

According to one aspect of the present invention, there is provided a material for a prosthesis for restoring a tooth defect, the material having a predetermined surface. The portion is formed in advance in a predetermined state, for example, in a form similar to the surface state of human teeth, in a state having transparency and color luster, and part or all of the predetermined surface part is unprocessed, and The non-processed portion forms a surface corresponding to the surface of the tooth at the time of non-deletion, and the other portion is processed so as to conform to the surface shape of the tooth-deleted portion.

In other words, the predetermined surface portion of the prosthetic material according to the first aspect of the present invention is formed in advance in a state similar to the surface state of a human tooth, in a state having transparency and gloss. . When processing the prosthesis material to form a prosthesis, the predetermined surface portion is left unprocessed,
This is a surface that replaces the surface when the tooth to be prosthetic is not lost (in other words, before the tooth is lost). On the other hand, other portions than the predetermined surface portion are, for example, cut or ground to a state suitable for the surface shape of the tooth missing portion. The surface formed by this processing becomes the bonding or connection surface with the surface of the above-mentioned tooth defect portion.

The external dimensions of the predetermined surface portion are as follows:
When the external dimensions of the non-deleted tooth to be prosthetic are substantially the same as those of the tooth, the entire predetermined portion is left unprocessed. On the other hand, when the external dimensions of the predetermined portion of the prosthetic material are not the same as the external dimensions of the non-deleted surface of the tooth to be prosthetic, the prosthetic material is reduced to such an extent that both become substantially equal. A part of a predetermined portion of the material is cut or ground.

As described above, according to the first aspect of the present invention, a surface portion of a tooth to be prosthetic can be prosthetic only by arbitrarily cutting or grinding a portion other than the predetermined surface portion. Prostheses such as veneer crowns can be formed. Further, since the predetermined surface portion is formed in advance in a state approximating the surface state of a human tooth, the predetermined surface portion is formed several times as in the conventional porcelain laminate veneer method described above in order to form this surface state. Also, there is no need to repeat the application and firing of the porcelain.

According to a second aspect of the present invention, in the prosthetic material according to the first aspect of the present invention, the state of the predetermined surface portion is similar to a surface state of a human tooth, and has a feeling of transparency and gloss. This is a certain white state.

That is, as in the invention according to claim 2,
By making the above-mentioned predetermined surface portion of the prosthetic material a form, a transparent feeling and a glossy color similar to the surface condition of human teeth, a prosthetic material more similar to human teeth can be provided.

According to a third aspect of the present invention, in the prosthetic material according to the first aspect of the present invention, the shape of the predetermined surface portion is a specific human tooth, such as a tooth to be prosthetic. It approximates the shape of a part or the whole.

For example, suppose now that a prosthesis for manufacturing a part of a human tooth for prosthesis is manufactured. In this case, as in the invention according to claim 3, the predetermined surface portion is replaced with a shape close to the partial surface of the tooth, for example, an external dimension, in place of the partial surface of the tooth to be prosthetic. In some cases, labor for processing the predetermined surface portion can be omitted. Further, even if it is necessary to process the predetermined surface portion, the amount of processing is small. On the other hand, in the case of manufacturing a prosthesis for prosthesis of a specific human tooth as a whole, if the predetermined surface portion has an outer dimension approximate to the entire surface of the tooth to be prosthetic, the predetermined Can be saved, or the effort can be reduced.

The shape of the tooth differs for each individual patient such as adult or child, or for each type of tooth such as front teeth, canines, maxillary teeth and mandibular teeth. Therefore, it is desirable to prepare a plurality of prosthetic materials in which the shape of the predetermined surface portion has various variations according to the types of the teeth.

According to a fourth aspect of the present invention, in the prosthetic material according to the first aspect of the present invention, the prosthesis includes a substantially planar portion of a human tooth, such as a front surface of a front tooth or a buccal surface of a canine tooth. In the prosthesis, the dental prosthesis material has a substantially flat plate shape and has the predetermined surface portion on one surface side.

That is, the prosthetic material of the invention according to the fourth aspect of the present invention has a veneer
It is intended to produce a crown. In this case, if the prosthesis material to be processed is a relatively thin flat plate as in the invention described in claim 4, the processing operation can be relatively easily performed.

According to a fifth aspect of the present invention, there is provided the prosthetic material according to the fourth aspect, wherein at least 4% of the total surface area
0% or more is processed.

[0020] The invention according to claim 5 is characterized in that:
In the invention according to claim 4, which is a prototype of the crown,
It specifically defines the processing area of the prosthetic material in forming the veneer crown. That is, since the predetermined surface portion which is not processed is formed on one surface side of the substantially flat prosthesis material, for example, when the entire one surface side of the prosthesis material corresponds to the predetermined surface portion, By simply processing the other surface of the prosthesis material, a prosthesis as its final form can be formed. Therefore, in this case, considering that the predetermined surface portion (that is, the surface of the tooth to be prosthetic) may be slightly curved, if at least 40% or more of the entire surface area of the prosthetic material is processed, the veneer may be processed. -A crown can be formed.

According to a sixth aspect of the present invention, in the prosthetic material according to the first aspect of the present invention, an index portion which has a predetermined relative positional relationship with the predetermined surface portion is provided.

Incidentally, the above-mentioned index portion is, for example,
The prosthesis material can be configured by marking dots or symbols on the surface of the prosthesis material with ink or the like, or by providing protrusions, holes, or the like on the surface of the prosthesis material. However, in the case where the indicator portion is formed by a three-dimensional shape such as a protrusion or a hole, the indicator portion is provided on a portion other than the predetermined surface portion. This is because, when these are provided on the predetermined surface portion, the surface state of the predetermined surface portion may be impaired when they are finally removed.

For example, it is assumed that the prosthetic material according to the sixth aspect of the present invention is to be held by some holding tool in order to process the material. In this case, if the index portion is used as a guide, the prosthetic material can be always held in a fixed state with respect to the holder.

Further, the above-mentioned index portion enables the following applications. That is, while the prosthesis material is being held by the holder, the position and direction of the index portion, preferably the position and direction in a three-dimensional space, are confirmed. Then, based on the position and direction of the index portion obtained after the confirmation, a base point of the prosthetic material itself and a three-dimensional coordinate system centered on the base point are formed. Since the predetermined surface portion of the prosthetic material has a predetermined relative positional relationship with the index portion, the predetermined surface portion also has a position on a coordinate system with respect to the prosthetic material itself. Can be specified. Therefore, if processing is performed based on a coordinate system based on the prosthesis material itself to be processed, the holding state of the prosthesis material by the holding tool (for example, the holding accuracy of the holding tool and the holding position and orientation of the prosthesis material) Etc.), high-precision machining can always be realized.

When the prosthetic material is held in the holder, the position of the index portion must be checked first, and thereafter (unless the prosthetic material is removed from the holder during processing). In addition, the above-mentioned index part becomes unnecessary. Therefore, after confirming the position of the indicator, this indicator is also processed,
It may be removed.

The position and direction of the index portion in the three-dimensional space can be confirmed by, for example, capturing the index portion from different positions by using two or more cameras, and converting a plurality of images, that is, stereo images (or images). This can be achieved by analysis. When the indicator has a three-dimensional shape such as a projection or a hole, a non-contact (optical) displacement meter such as a generally known laser displacement meter is used.
This displacement meter obtains the remaining one-dimensional coordinates of each scanning point while two-dimensionally scanning the surface of the indicator, or triangularly moves or rotates the two-dimensional scanning surface relatively in a three-dimensional space. By performing surveying, the position and direction of the indicator can be confirmed. In this case, for example, a contact displacement meter having a contact having a sharp tip may be used instead of the laser displacement meter.

According to a seventh aspect of the present invention, in the prosthetic material according to the sixth aspect, the index portion is provided on a portion other than the predetermined surface portion.

That is, as in the invention according to claim 7,
If the indicator is provided in a portion other than the predetermined surface portion, the mode of the indicator is not particularly limited. For example, in addition to marking dots or symbols on the surface of the prosthetic material with ink or the like as described above, the indicator portion can also be formed by a three-dimensional shape such as a protrusion or a hole.

According to an eighth aspect of the present invention, in the prosthetic material according to the seventh aspect, the dental prosthesis prostheses a substantially planar portion of a human tooth. The prosthetic material for use is a substantially flat plate-like material having the predetermined surface portion on one surface side and the indicator portion on the other surface side.

[0030] The prosthetic material of the invention according to claim 8 is:
The purpose is to manufacture the veneer crown as a prosthesis in its final form. An index portion is provided on the back side of the predetermined surface portion, that is, on the side that is always processed. In this way, if an index portion that is finally unnecessary is provided on the side where the prosthesis material is always processed, the index portion is simultaneously processed and removed when the prosthesis material is processed. Can increase productivity.

According to a ninth aspect of the present invention, in the prosthetic material according to the seventh aspect of the present invention, the index portion is a projection having a predetermined shape.

That is, as in the invention according to claim 9,
It is easier to confirm the position of the index portion for positioning if it is a projection having a three-dimensional shape than a mark which is marked with ink or the like or a planar one. Also, the shape of the projection
If the shape is a predetermined shape, for example, a hemispherical shape, a semi-elliptical shape (a shape obtained by halving a so-called elliptical rotating body), a polygonal pyramid or a conical shape, the base point of the protruding portion itself, for example, the center or the vertex can be accurately specified. And, consequently, 3 of the prosthesis material itself to be processed
The position and direction in the dimensional space can be specified accurately. Such projections also have the advantage of being relatively easy to manufacture.

According to a tenth aspect of the present invention, in the prosthetic material according to the ninth aspect, the shape of the protrusion is:
It has a substantially hemispherical shape, a substantially semi-elliptical shape, a roughly polygonal pyramid shape, or a roughly conical shape.

That is, according to the tenth aspect of the present invention, the shape of the projection forming the indicator is specified, and the same effect as the ninth aspect is achieved.

According to an eleventh aspect, in the prosthetic material according to the sixth aspect, a plurality of the index portions are provided.

According to the eleventh aspect of the present invention, since a plurality of index portions are provided, positioning of the prosthetic material can be more accurately achieved, and more accurate processing can be achieved.

According to a twelfth aspect of the present invention, there is provided the prosthetic material according to the first aspect, wherein the type of teeth to be prosthetic, for example, individual differences between patients such as adults and children, or front teeth and canines. A plurality of types are prepared in advance in accordance with the type of tooth such as the upper and lower teeth and the type of the color of the tooth surface.

That is, if the type of the tooth to be prosthetic is different, the shape, color, and the like of the surface portion of the tooth to be prosthetic are naturally different. Therefore, as in the invention according to the twelfth aspect, a plurality of variations having various shapes and colors of the predetermined surface portion are prepared according to the type of the tooth to be prosthetic. In this way, for various prosthetic objects,
Efficient responses can be made, and productivity can be improved.

[0039]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to, for example, the above-described prosthetic material for veneer crown will be described with reference to FIGS. Also in this embodiment, similarly to the above-mentioned conventional porcelain laminate veneer method, for example, a plaster model 1 of a diseased tooth as shown in FIG. 2 is taken. Although FIG. 2 shows the case of the lower jaw, the same applies to the case of the upper jaw. Then, based on the gypsum model 1, a veneer crown 2 for prosthesis of a portion to be prosthetic, for example, a portion 1a indicated by oblique lines in FIG.

However, the conventional porcelain laminate
In the veneer method, a porcelain material is directly applied to the surface of a portion to be prosthetic of the gypsum model 1 (strictly, a portion corresponding to a portion to be prosthetic of a diseased tooth) 1a, and the porcelain is baked. Does not do this. That is, in the present embodiment, the external dimensions of the prosthesis target portion 1a of the gypsum model 1 and its peripheral portion are measured as curved surface data in a three-dimensional space. Then, based on the measurement data of the curved surface in the three-dimensional space obtained by this measurement, the ceramic prosthesis material 3 shown in FIG. 1 according to the present embodiment is cut or ground, and this prosthesis material 3 is obtained. A veneer crown 2 is formed, that is, cut out to prosthesis the prosthesis target portion 1a as a prototype. This is a major difference from the conventional porcelain laminate veneer method according to the present embodiment, and is the greatest feature.

As shown in FIG. 1, the prosthetic material 3 has a disk-shaped base portion 31. One surface of the base portion 31, for example, the surface (the upper surface in FIG. 3A) has a substantially central portion thereof, which is similar to a part of a human tooth, for example, a front portion of a front tooth or a cheek side portion of a canine tooth. A pseudo surface 32 having a predetermined shape is formed. And this pseudo surface 32 is
It is formed in a form similar to the surface condition unique to human teeth, in a transparent and glossy white state. The pseudo surface 32 corresponds to a predetermined surface portion described in the claims, and serves as a surface (front or cheek side) of the veneer crown 2 which is the final form of the prosthetic material 3. In the present embodiment, the diameter of the base portion 31 is about 30 mm,
The thickness dimension is about 1 mm.

On the other hand, a plurality of, for example, two hemispherical projections 33 are provided on the back surface of the base portion 31 at a distance from each other with their respective centers located on the diameter of the base portion 31. Is formed. These projections 33, 3
Reference numeral 3 denotes an index portion for determining a reference position in a later-described processing step, and is finally removed together with the base portion 31. Then, the back side of the base portion 31 is cut or ground to a state conforming to the surface shape of the prosthesis target portion 1a, and becomes a contact surface with the prosthesis target portion 1a.

The prosthetic material 3 may be made in accordance with the type of teeth to be prosthetic, specifically, individual differences between patients such as adults and children, or teeth such as front teeth, canines, upper teeth and lower teeth. A plurality of types are prepared in advance in which the shape of the pseudo surface 32 is variously varied according to the type of the tooth surface or the type of the color of the tooth surface. Then, by proceeding according to the procedure shown in FIG. 3, the veneer crown 2, which is the final form, is formed from each prosthetic material 1.

As shown in the figure, first, the external dimensions of the portion 1a to be prosthetic and the peripheral portion of the plaster model 1 are measured as curved surface data in a three-dimensional space (step S2). To perform this measurement, for example, a three-dimensional measuring device 4 as shown in FIG. 4 is used. This uses a generally known laser displacement meter 41, and two-dimensionally scans the measurement points on the surface of the gypsum model 1 by the laser displacement meter 41 with the three-dimensional stage 42, and the remaining one at each of these scanning points is used. While obtaining two-dimensional coordinate data, or rotating or translating a two-dimensional scanning surface relatively in a three-dimensional space, three-dimensional coordinates of each scanning point are determined based on a triangulation method.
Derive dimensional coordinates.

The process of deriving the three-dimensional coordinates at each of the curved scanning points while scanning the measurement points by the laser displacement meter 41 with the three-dimensional stage 42 is realized by the control of the CPU 43. And C
The PU 43 transmits the derived measurement data of the three-dimensional coordinates of the curved surface to, for example, a display unit 44 of a CRT or a liquid crystal panel configuration.
Display by numerical value or figure. Note that the CPU 43
These operations are executed in accordance with a program stored in a storage unit 45 having a semiconductor memory configuration such as a ROM or a RAM, and the execution instruction is given by, for example, an operation unit 46 having a keyboard configuration.

Here, assuming that the surface data in the three-dimensional space relating to the respective external dimensions of all the prosthetic material 3 prepared in advance are known, the known surface data and the surface obtained by the above measurement are obtained. From the data, which of the prosthesis materials 3 is suitable for prosthesis of the prosthesis target portion 1a (specifically, whether or not the prosthesis material 3 has the pseudo surface 32 having a shape suitable for prosthesis of the prosthesis target portion 1a) And where and how to cut or grind the prosthetic material 3 so that the prosthetic object portion 1a can be satisfactorily prosthetic.
Can be recognized.

Therefore, first, each of the above-mentioned known curved surface data and the measured surface data are collated, and each prosthetic material 3
Are determined to be suitable for prosthesis of the prosthesis target portion 1a. However, if the respective surface data are collated as they are, an enormous amount of data must be processed, which takes time. In order to speed up this processing, in the present embodiment, contour data relating to each contour of the prosthetic material 3 and the prosthesis target portion 1a is derived from each of the curved surface data. And
Data matching is performed between the curve data in the three-dimensional space called the contour data.

That is, generally known edge enhancement processing is performed on each of the above-described known surface data and the measured surface data. Thereby, each prosthetic material 3
And each outline data of the prosthesis target part 1a is obtained (step S4). At this time, it is supposed that the data on the contour of each prosthetic material 3 and the prosthesis target portion 1a to be derived can be changed.

Then, the contour data obtained in step S4 is subjected to a feature extraction process using, for example, a perimeter or an area as a feature amount, and each contour data of each prosthetic material 3 obtained by this process is processed. The feature extraction amount is compared with the feature extraction amount of the prosthetic target portion 1a, and a deviation between them is obtained. Then, the prosthetic material 3 corresponding to the feature extraction amount having the smallest deviation from the feature extraction amount related to the prosthesis target portion 1a
Is determined to be most suitable for prosthesis of the prosthesis target portion 1a, and the veneer crown 2 is used to realize the prosthesis.
(Step S6).

However, in step S6, based on curve data in a three-dimensional space called contour data,
Since the prosthetic material 3 which is suitable for strictly prosthesis for the prosthetic target portion 1a is selected, the prosthetic material 3 obtained by selecting the prosthetic material portion 3a may be used to prosthesis the prosthetic target portion 1a. There may be cases where the conditions necessary for the operation are not satisfied. For example, even when the contour shape of the prosthetic material 3 (strictly speaking, the pseudo surface 32) obtained in step S6 is substantially equal to the contour shape of the prosthesis target portion 1a, the prosthesis material 3 is selected and obtained. There may be a case where the dimension of the prosthetic material 3 in the thickness direction is less than a thickness dimension sufficient to prosthesis the prosthesis target portion 1a.

Therefore, the prosthetic material 3 obtained by the selection in step S6 is processed to determine whether or not the conditions necessary to actually prosthetic the prosthetic portion 1a are satisfied. Beforehand, it is calculated and confirmed in a simulated manner (step S8). That is, in order to form the veneer crown 2 for prosthesis of the prosthesis target portion 1a, the surface data relating to the outer dimensions of the prosthetic material 3 obtained by the above selection and the curved surface in the three-dimensional space of the prosthesis target portion 1a When the prosthetic material 3 is processed based on the curved surface data obtained by measuring
The shape of the processed prosthetic material 3 (the veneer / crown 2) is simulated. Then, when the prosthetic material 3 obtained by the selection satisfies the conditions necessary for prosthesis of the prosthesis target portion 1a (Y in step S8).
In the case of ES), the process proceeds to the next step S12 in order to actually process the prosthetic material 3. On the other hand, when the prosthetic material 3 does not satisfy the conditions necessary for prosthesis of the prosthesis target portion 1a, for example, when the thickness of the prosthetic material 3 is insufficient (NO in step S8), the above-described step is performed. Returning to S6, the prosthetic material 3 is selected again. At that time, the prosthetic material 3 that does not satisfy the prosthetic conditions is excluded from the selection.

The above steps S4 to S8
The steps up to are performed by the three-dimensional measuring device 4. More specifically, the CPU 43 executes various data processes in order to perform the steps according to the program stored in the storage unit 45. In order to realize this data processing, it is necessary to provide the CPU 43 with three-dimensional data relating to the outer diameter of each prosthetic material 3. These data are stored in the storage unit 45 in advance. It is remembered.

After selecting the prosthetic material 3 serving as the prototype of the veneer crown 2 as described above, the selected prosthetic material 3 is then processed by a processing device shown in FIGS. 5 to 8, for example. Actually process. 5, 6, and 7 are front, right, and plan views, respectively, of the processing apparatus, and FIG. 8 is a block diagram showing an electrical schematic configuration thereof.

As shown in FIG. 5 to FIG.
A base table 5 having a flat upper surface, an X-axis slide table 6 provided on the base table 5, a Y-axis slide table 7 provided on the X-axis slide table;
A Z-axis slide table 8 provided on the axis slide table 7. The X-axis slide table 6 includes a base 61 fixed on the base 5 and a horizontal direction of the apparatus on the base 61 (hereinafter referred to as X direction).
Called the axial direction. A) a driving unit 62 that slides along
Consists of The drive section 62 is driven by an X-axis direction drive motor 63 shown in FIG. Further, the Y-axis slide table 7 has a base 71 fixed on the drive unit 62 of the X-axis slide table 6, and the base 71 is located in the front-rear direction of the apparatus (hereinafter, this direction is referred to as the Y-axis direction). ), And a driving unit 72 that slides along the driving direction. The drive section 72 of the Y-axis slide table 7 is driven by a Y-axis direction drive motor 73 shown in FIG. The Z-axis slide table 8 includes a base portion 81 fixed on the drive section 72 of the Y-axis slide table 7 and a front side surface of the base portion 81 in a vertical direction of the apparatus (hereinafter, this direction is referred to as a Z-axis direction). And a drive unit 82 that slides along the drive unit 82). The drive section 82 of the Z-axis slide table 8 is driven by a Z-axis direction drive motor 83 shown in FIG.

Further, the drive unit 8 of the Z-axis slide table 8
A spindle 10 having, for example, a disk-shaped grindstone 101 serving as a processing tool for the prosthesis material 3 is provided via a rotary table 9 on a front side surface of the workpiece 2. That is, the turntable 9 is provided with a base portion 91 fixed to the front side surface of the drive section 82 and a front side surface of the base portion 91, and is indicated by an arrow 92 in FIG. 5 about an axis along the X-axis direction. And a rotation drive unit 93 that rotates in the direction. Then, on the front side surface of the rotation drive unit 93, the spindle 10 causes the rotation shaft 102 having the grinding wheel 101 at the tip to follow the X-axis direction, and the tip of the rotation shaft 102 to the right side toward the front of the apparatus. It is fixed by the fixing jig 103 in the turned state. This spindle 10 (rotation shaft 102)
It is driven by DC or AC power supplied from a power supply device (not shown). The rotation drive unit 93 is driven by a rotation drive motor 94 shown in FIG.

The grinding wheel 101 of the spindle 10
The prosthetic material 3 to be processed by this device is placed in the space below where is located. That is, the fixed table 11 and the rotary table 1 are placed on the base table 5 in this space.
A holder for holding the prosthetic material 3, for example, a generally known freezing chuck 13 is provided via the base 2. The freezing chuck 13 holds the prosthetic material 3 using ice as a medium, and in order to realize this, on the upper part of the freezing chuck 13, as shown in FIG. A round hole 132 for receiving a freezing agent, for example, water 131 is provided. This round hole 1
The diameter of the prosthesis material 3 is slightly smaller than the diameter of the base portion 31 of the prosthesis material 3, and the prosthesis material 3 has the pseudo surface 32 facing the inside of the round hole 132, in other words, the index described above. The parts 33 are provided with the parts 33 facing upward and the round holes 132 are closed by the base part 31. In the vicinity of the round hole 132, for example, near the bottom of the round hole 132,
An electronic cooling element (Peltier element) 133 is provided. By operating the electronic cooling element 133, the water 131 in the round hole 132 is frozen, and the prosthetic material 3 is fixed.

The rotary table 12 supporting the freezing chuck 13 has a base portion 121 fixed on the fixed base 11 and, above the base portion 121, a center along an axis along the Z-axis direction as shown in FIG. And a rotation drive unit 123 that rotates in the direction indicated by the arrow 122. Then, the freezing chuck 13 is fixed on the rotary drive unit 123, and the rotary drive unit 123 is driven by a rotary drive motor 124 shown in FIG.

By the way, each of the drive motors 63, 73,
83, 94, and 124, as shown in FIG.
It is connected to the CPU 14 of this processing device. This CPU 14 is based on the above-described curved surface data in the three-dimensional space related to the outer diameter of the prosthetic material 3 and the curved surface data in the three-dimensional space obtained by measuring the prosthesis target portion 1a.
It works as follows. It should be noted that the storage unit 15 in the processing device also stores in advance the curved surface data in the three-dimensional space relating to the outer dimensions of the prosthetic material 3. Also,
The surface and curve data in the three-dimensional space obtained by measuring the prosthesis target portion 1a are obtained from the three-dimensional measurement device 4 described above.
It is transferred to PU14.

That is, after the prosthetic material 3 to be processed is held by the freezing chuck 13 (step S12), the positions and directions of the index portions 33 of the prosthetic material 3 in the three-dimensional space are confirmed (step S12). S14). This confirmation is performed by a triangulation method using a laser displacement meter (not shown) as in FIG.

Here, since each of the index portions 33, 33 is a hemispherical projection, the respective centers, which can be said to be the respective base points, can be accurately specified from their appearance. On the other hand, if each of the index portions 33 is a projection having a shape with many planes and many corners such as a rectangular parallelepiped, for example, depending on the appearance, a base point such as a center position may be used. May not be able to specify the exact position. The same applies to the case where the indicator portions 33, 33 are formed in a planar shape, for example, by simply marking them with ink or the like. Therefore, as in the present embodiment, the indicator units 33, 33
The shape of each of the index portions 33, 3
It is very useful for pinpointing the position of No. 3. Note that, even when the index portions 33 are formed of, for example, semi-elliptical projections, the center position and direction can be specified from the appearance thereof.
3, 33 may be adopted. In addition, the indicator 3
When the projections 3 and 33 are formed of, for example, polygonal pyramidal or conical projections, their vertices and their directions can be specified from the appearance thereof. May be adopted. Such a projection also has the advantage that it is relatively easy to manufacture.

Next, data relating to the center position and direction of each of the index portions 33, 33 obtained in step S14 is transferred to the CPU 14. Thereby, the CPU 1
4, reference numerals 3 of the prosthetic material 3 as shown in FIG.
A straight line passing through each center of 3, 33 is defined as an x-axis, and a straight line perpendicular to the x-axis, passing through a midpoint O between the index portions 33, 33 and along the back surface of the base portion 31 is defined as a y-axis, A prosthetic material 3 having a straight line perpendicular to these x-axis and y-axis as the z-axis.
A coordinate system [x, y, z] based on itself is formed.
Then, each coordinate system of the curved surface data in the three-dimensional space related to the outer shape of the prosthetic material 3 and the curved surface data obtained by measuring the curved surface in the three-dimensional space of the prosthesis target portion 1a is represented by the prosthesis. The object material 3 itself is converted into a coordinate system [x, y, z] based on the object material 3 itself (step S16).

After converting the coordinates, the CPU 14 converts the veneer crown 2 having a desired shape to satisfactorily prosthetic the prosthesis target portion 1a based on the coordinate system [x, y, z] obtained by the conversion. To form, the grinding wheel 10 of the spindle 10 is used.
In step S18, so-called processing data (tool path) for determining where and how to grind the prosthetic material 3 should be prepared. The drive motors 63, 73, 83, 94, and 124 are controlled based on the processing data created in step S18. Thus, the prosthetic material 3 is ground by the grindstone 101 of the spindle 10 (step S20), and a portion of the prosthetic material 3 excluding a part or all of the pseudo surface 32, that is, a pseudo portion including the index portions 33, 33 is provided. The back side of the surface 32, the base portion 31 and possibly the peripheral portion of the pseudo surface 32 are ground away and the final form of the veneer crown 2 is removed.
Is formed.

The operation of the CPU 14 is performed by the storage unit 1
5 is controlled by a program stored in the memory 5. Then, the instruction is given by an operation unit 16 having a keyboard configuration, for example, connected to the CPU 14.

As described above, according to the present embodiment, the prosthesis target portion 1a can be satisfactorily restored only by grinding other portions except for part or all of the pseudo surface 32 of the prosthesis material 3. The veneer crown 2 can be formed as desired. In addition,
If the area of one side of the substantially disc-shaped prosthetic material 3 (base portion 31) is reduced to an area approximately equal to the pseudo surface 32, only the substantially other side (back side) of the prosthetic material 3 is reduced. The veneer crown 2 can be formed only by processing. In this case, considering that the pseudo surface 32 is slightly curved, the veneer crown 2 can be formed by processing at least 40% or more of the entire surface area of the prosthetic material 3. The pseudo surface 32 of the prosthetic material 3 corresponding to the surface of the veneer crown 2 is formed in advance in a form similar to the surface state of human teeth, in a transparent and glossy white state. It is not necessary to repeat the porcelain application and firing operations as many times as in the conventional porcelain laminate veneer method described above. Therefore, the veneer crown 2 can be easily and inexpensively manufactured as compared with the conventional porcelain laminate veneer method.

Further, the CPU 43 hardly touches human hands.
Based on the measurement data and the like obtained by measuring the gypsum model 1 by the three-dimensional measuring device 4 provided with the CPU, the processing device provided with the CPU 14 substantially automatically grinds the prosthetic material 3 to obtain the desired veneer crown Since the veneer crown 2 is manufactured, the veneer crown 2 of a constant quality can be efficiently produced.

Then, the prosthesis material 3 is
When processing is performed, the CPU 14 performs cutting based on the coordinate system [x, y, z] of the prosthetic material 3 itself to be processed. Therefore, for example, even when the holding accuracy of the prosthetic material 3 by the freezing chuck 13 is not so high, or the direction of the prosthetic material 3 with respect to the freezing chuck 13 is not constant, accurate grinding can be always realized.

In this embodiment, the veneer crown 2 is used as a prosthesis to prosthetic the surface of the affected tooth.
Has been described, but the present invention can also be applied to the case of forming a prosthesis for restoring other parts.

In order to measure the shape of the gypsum model 1 and the positions and directions of the index portions 33 of the prosthetic material 3, FIG.
The non-contact type three-dimensional measuring device 4 as shown in FIG.
Not limited to this. For example, the above-described three-dimensional measurement can be realized by analyzing a stereo image using a generally-known contact-type measuring device having a contactor or two or more cameras.

The material and shape of the prosthetic material 3 and the structure of the processing device are not limited to those described in the present embodiment. For example, three or more index portions 33 of the prosthetic material 3 may be provided. With this configuration, the positions of the index portions 33, 33 can be specified more accurately, and the index portions 33, 3 can be identified by simple marks such as ink.
A certain degree of accuracy can be expected even when 3 is formed.
In addition, when the prosthesis material 3 is processed, grinding is performed, but other processing such as cutting may be performed in addition to the grinding.

If the fitting of the veneer crown 2 finally obtained by the grinding process to the prosthetic object portion 1a is insufficient, the veneer crown 2 is manually operated by a dentist or a dental technician. The crown 2 may be finely processed. Also, in step S6 in FIG.
When selecting a prosthetic material 3 suitable for prosthesis for the prosthesis target portion 1a, this operation may be performed by a manual operation of, for example, a dentist or a dental technician, without depending on the measuring device 4 described above.

[0071]

As described above, according to the present invention, the veneer material is used to prosthetic the surface of the tooth only by cutting or grinding the portion other than the predetermined surface of the prosthetic material.
Prostheses such as crowns can be formed. The predetermined surface portion is formed in advance in a form similar to the surface state of a human tooth, in a transparent and glossy white state so as to replace the surface of the tooth to be prosthetic. In order to form the state, it is not necessary to repeat the application and firing of the porcelain as many times as in the conventional porcelain laminate veneer method described above. Therefore, conventional porcelain
There is an effect that a prosthesis can be manufactured easily and inexpensively as compared with the laminate veneer method.

[Brief description of the drawings]

1A and 1B are external views of a prosthetic material according to an embodiment of the present invention, in which FIG.
Is a view of the back surface viewed obliquely, and (c) is a side view.

FIG. 2 is a perspective view of a gypsum model in which a diseased tooth is modeled in the embodiment.

FIG. 3 is a flowchart showing a flow of a series of prosthetic operations in the embodiment.

FIG. 4 is a block diagram showing a schematic configuration of a three-dimensional measuring device according to the embodiment.

FIG. 5 is a front view of the processing apparatus according to the embodiment.

FIG. 6 is a right side view of the processing apparatus according to the embodiment.

FIG. 7 is a plan view of the processing apparatus according to the embodiment.

FIG. 8 is a block diagram showing a schematic configuration of a processing apparatus in the embodiment.

FIG. 9 is a longitudinal sectional view showing a schematic configuration of a holder for the prosthetic material according to the embodiment.

FIG. 10 is a diagram showing a coordinate system based on the prosthesis material itself according to the embodiment.

[Explanation of symbols]

 3 prosthesis material 31 base part 32 pseudo surface 33 indicator part

Continuation of the front page (72) Inventor Toshiaki Ikeda 1-42 Shinsenri Higashicho, Toyonaka City, Osaka Prefecture, Japan 1212F, Senri Life Science Center Building Room 1220 Inside Lifetech Research Institute, Inc. (72) Inventor Toshiyuki Nanbu New Toyonaka City, Osaka Prefecture 1-42, Senri-Higashicho 1212F, Senri Life Science Center Building Room 1220 F-Term in Lifetech Research Laboratories Co., Ltd. 4C059 JJ02 RR01 RR20 TT10

Claims (12)

[Claims] 1. A material for a dental prosthesis for restoring a missing tooth part, wherein a predetermined surface portion is formed in a predetermined state in advance, and a part or all of the predetermined surface portion is formed. A dental prosthesis that is unprocessed and forms a surface corresponding to the surface of the tooth at the time of non-deficiency by the non-processed portion, and the other portion is processed to a state that conforms to the surface shape of the tooth missing portion. Material. 2. The dental prosthesis material according to claim 1, wherein the state of the predetermined surface portion is approximated to the surface state of human teeth. 3. The dental prosthesis material according to claim 1, wherein the shape of the predetermined surface portion is approximated to the shape of a part or the whole of a specific human tooth. 4. The dental prosthesis, which prostheses a substantially planar portion of a human tooth, wherein the dental prosthesis material is a substantially flat plate, and the predetermined surface is provided on one side thereof. The dental prosthesis material according to claim 1, having a surface portion. 5. The dental prosthesis material according to claim 4, wherein at least 40% or more of the total surface area is processed. 6. The dental prosthesis material according to claim 1, further comprising an index portion having a predetermined relative positional relationship with the predetermined surface portion. 7. The dental prosthesis material according to claim 6, wherein the index portion is provided on a portion other than the predetermined surface portion. 8. The dental prosthesis for prosthesis of a substantially planar part of a human tooth, wherein the dental prosthesis material is a substantially flat plate-like material, and the predetermined surface of the dental prosthesis material is provided on one side. 8. A surface part and said indicator part on the other side.
A dental prosthesis material according to item 1. 9. The dental prosthesis material according to claim 7, wherein the index portion is a projection having a predetermined shape. 10. The dental prosthesis material according to claim 9, wherein the shape of the projection is a substantially hemispherical shape, a substantially semi-elliptical shape, a substantially polygonal pyramid shape, or a substantially conical shape. 11. The dental prosthesis material according to claim 6, wherein a plurality of the index portions are provided. 12. Depending on the type of tooth to be prosthetic,
The dental prosthesis material according to claim 1, wherein a plurality of types are prepared in advance.