JPH1052445A - Artificial dental root manufacturing method and artificial dental root - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable to manufacture a relatively thin artificial dental root with precision, by making a material to be worked to be a screw type dental root autorotate to approach a discharge electrode of an electric discharging machine to a screw forming part of the material and threading the threads moving the discharge electrode and the material to be worked relatively. SOLUTION: This dental root 4 comprises a head 5 to be held on a rotation indexing device 8 by a chuck 9, a neck part 6, and a screw forming part 2. Innumerable discharge marks with the size of about 0.01-0.03 are formed on the screw forming part 2 to which threads 3 are threaded to make the surface satin-finished. When such a dental root as that is manufactured, a material 1 to be worked is mounted on the rotation indexing device 8 to approach a wire electrode 10 to a screw forming part 2 to thread threads 3. Since such discharge working as this cuts a material to be worked without applying pressure, even a thin artificial dental root generates no strain to thread the threads 3 precisely.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an artificial tooth root called a screw type.

[0002]

2. Description of the Related Art An artificial tooth root having a screw-shaped appearance called a screw type is generally manufactured by casting, rolling, forging, or cutting a screw on a thread forming portion of a material to be processed. It is. The thread forming portion includes a straight shape having a constant diameter and a tapered shape having a diameter decreasing toward the tip.

[0003]

In each of the above-described methods for manufacturing an artificial tooth root, any of casting, rolling, and forging requires a die. Obviously, a manufacturing method requiring a mold is not suitable for cost. In addition, if casting is taken as an example, there is a problem of mixing of foreign matter and bending strength in a manufacturing process, and it is not always suitable for a method of manufacturing an artificial tooth root.

[0004] In the case of cutting, there is a problem of machining accuracy. For example, the diameter is less than 2mm and the length is
If you try to manufacture a screw type artificial tooth root of 20 mm or more by cutting, the tip of the thread-shaped part of the workpiece to be an artificial tooth root will be deformed or the screw thread will be uneven, and you will obtain the artificial tooth root as designed It is difficult.

[0005] Therefore, in artificial tooth roots of a small variety of various types, in particular, artificial tooth roots called screw type are inexpensive and relatively thin artificial roots (diameter 2 mm or less, length 20 mm or more).
Also decided to consider a method of manufacturing as an accurate product. In the study, attention was paid so that a screw forming portion having a straight shape and a tapering shape could be formed by the same manufacturing method without distinction.

[0006]

As a result of the examination, the developed thing is to rotate a workpiece to be a screw type artificial tooth root, and to apply a discharge electrode of an electric discharge machine to a thread forming portion of the workpiece. This is a method for manufacturing an artificial tooth root in which a thread is cut in the screw forming portion while moving the discharge electrode and the material to be processed close to each other. In this manufacturing method,
(1) The relative speed between the screw forming part and the discharge electrode, (2) the angle of the discharge electrode with respect to the screw forming part, or (3) the proximity distance of the discharge electrode to the screw forming part, the relative distance between the discharge electrode and the workpiece. You may make it variable according to a position.

As the material to be processed, a material that has been cut into a rough shape from a plate material or a rod material as a raw material in advance by cutting or electric discharge machining is used. The material to be processed is usually divided into a head, a neck, and a thread forming portion. The thread forming portion has a straight shape having a constant diameter and a taper shape having a tapered diameter. The head of the workpiece is mounted on a chuck of a rotary indexing device and rotated. The discharge electrode includes a plate electrode or a rod electrode in addition to a wire electrode.

The pitch of the thread formed in the thread forming portion is determined by the relative speed between the thread forming portion and the discharge electrode, and the lead angle is determined by the angle of the discharge electrode with respect to the thread forming portion.
Therefore, by making the relative speed variable according to the relative position of the discharge electrode and the workpiece in the rotation direction, the pitch of the screw thread can be made variable, and by making the angle variable as well. The lead angle of the thread can be made variable. Furthermore, when the proximity distance of the discharge electrode to the thread forming portion is made variable according to the relative position of the discharge electrode and the workpiece in the rotation axis direction, the thread forming portion of the workpiece cut straight is tapered. can do.

[0009] The artificial tooth root having the thread cut in this way is of a screw type, and the surface of the thread forming portion has a matte surface (rough surface having minute irregularities formed of discharge traces having a diameter of 0.01 to 0.03 mm). In the method for producing an artificial tooth root of the present invention,
The greatest advantage is that it is possible to cut accurate threads on relatively thin workpieces by EDM.However, as a secondary effect, the surface of the thread forming part that has undergone EDM becomes a matte surface. Implanting an artificial tooth root also has the advantage that tooth bones bite into the pear ground and implant stability is enhanced.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of a workpiece 1 cut out from a raw material (titanium or titanium alloy). FIG. 2 is a diagram illustrating a thread 3 formed on the thread forming portion 2 from the workpiece 1 by the manufacturing method of the present invention. FIG. 3 is a perspective view of the artificial dental implant 4, and FIG. 3 is an enlarged view of a thread 3 of the artificial dental implant 4.
As shown in FIGS. 1 and 2, the workpiece 1 and the artificial root 4 each include a head 5, a neck 6, and a screw forming section 2. As shown in FIG. 3, the thread forming portion 2 having the thread 3 formed by the manufacturing method of the present invention has a diameter.
Innumerable discharge marks 7 of 0.01 to 0.03 mm are formed, forming a pear surface (FIG. 3 illustrates a hole of a size that can be visually recognized for the sake of explanation, but in reality there are more smaller discharge marks Do).

FIG. 4 shows a state in which the head 5 of the workpiece 1 is mounted on the chuck 9 of the rotary indexing device 8 and the wire electrode 10 of the electric discharge machine (not shown) is brought close to the screw forming section 2 while rotating. , A rotary indexing device 8 showing a state in which the screw thread 3 is cut
FIG. 5 is a side view corresponding to FIG. 4 showing a state in which a bar electrode 11 is brought close to the screw forming portion 2 and the screw thread 3 is cut in place of the wire electrode 10. In this example, a wire electrode 10 (see FIG.
Is moved from the end of the thread forming portion 2 to the neck 6, but may be moved from the neck 6 to the end of the thread forming portion 2, or The material 1 may be moved. Since electric discharge machining cuts the workpiece 1 without applying pressure, even if the artificial tooth 4 is relatively thin (less than 2 mm in diameter and more than 20 mm in length), it can cut the thread 3 accurately without producing distortion. (See FIG. 2).

The pitch of the thread 3 is determined by the rotation speed of the workpiece 1 and the relative speed between the workpiece 1 and the wire electrode 10. The lead angle of the thread 3 depends on the rotation speed of the workpiece 1 and the relative speed between the workpiece 1 and the wire electrode 10, as well as the angle of the wire electrode 10 with respect to the workpiece 1. The size of each thread 3 is determined by the proximity distance of the wire electrode 10 to the workpiece 1. For example, based on the example of FIG.
Is inclined with respect to the traveling direction, the lead angle of each screw thread 3 increases (FIG. 6: side view corresponding to FIG. 4), and the wire electrode 10
If the traveling speed is increased, the pitch of the thread 3 becomes larger.
(FIG. 7: side view equivalent to FIG. 4). As described above, the thread 3 of the thread forming portion 2 according to the present invention adjusts the lead angle and pitch depending on the positional relationship between the wire electrode 10 and the workpiece 1.

As shown in FIG. 8 (a side view corresponding to FIG. 4), the lead angle can be adjusted by tilting the workpiece 1 with respect to the vertical wire electrode 10. FIG. 9 (FIG. 4)
(Equivalent side view), the angle of the wire electrode 10 with respect to the workpiece 1 is
It is also possible to carve a screw thread 3 with a changed lead angle by making it variable in accordance with the relative position of. Similarly, by making the relative speed between the wire electrode 10 and the workpiece 1 variable, the pitch of the screw thread 3 can be made variable, but the illustration of the description is omitted.

If the manufacturing method described above is applied, it is also possible to cut the tapered screw thread 3. FIG. 10 is a side view corresponding to FIG. 4 showing a state in which the thread 3 is formed while the wire electrode 10 is inclined with respect to the workpiece 1 in which the thread forming portion 2 is cut out in a truncated cone shape. FIG. 5 is a side view corresponding to FIG. 4 showing a state in which the thread 3 is formed while tilting the wire electrode 10 with respect to the workpiece 1 having the straight thread forming portion 2 equivalent to FIG. In any case, the wire electrode 3 for the workpiece 1 is formed because the thread 3 having a constant pitch and a lead angle is formed in the tapered thread forming portion 2.
10 angles and moving speed are variable according to the relative position. Although the manufacturing method of the present invention mainly focuses on engraving the screw thread 3 in the thread forming portion 2 of the workpiece 1 having a substantially contoured outer shape, since the electric discharge machining is originally a non-contact cutting process, As can be seen from FIG. 11, the tapered thread 3 can be cut from the straight thread forming portion 2 by adjusting the proximity distance between the workpiece 2 and the wire electrode 10.

[0015]

According to the artificial tooth root manufacturing method of the present invention, a screw-type artificial tooth root having a diameter of 2 mm or less and a length of 20 mm or more, which is relatively thin, can be accurately cut with no distortion without having distortion. it can. Artificial dental implants are generally made to order for each patient and require different processing. The manufacturing method of the present invention has the effect of responding to this demand, and of being able to easily produce a fine artificial tooth even with a thin artificial tooth which was difficult with the conventional manufacturing method.

[0016] In addition, the artificial tooth root produced by the manufacturing method of the present invention has good bite of the tooth bone, and is strong and stable for a long period of time because the screw forming part embedded in the tooth bone forms a matte surface. Can be embedded. In addition, since the processing accuracy is high as described above, even a thin artificial tooth root can be finished to a required shape, so that an optimized artificial tooth root can be provided to a patient.

[Brief description of the drawings]

FIG. 1 is a perspective view of a workpiece.

FIG. 2 is a perspective view of an artificial root having a thread formed in a thread forming portion according to the manufacturing method of the present invention.

FIG. 3 is an enlarged view of a screw thread of the artificial tooth root.

FIG. 4 is a side view of a rotary indexing device in which a head of a material to be processed is mounted on a chuck, a wire electrode is brought close to a screw forming portion while rotating, and a screw thread is formed.

FIG. 5 is a diagram corresponding to FIG. 4 showing a state in which a bar-shaped electrode is brought close to the thread forming portion and a thread is cut in place of the wire electrode.

FIG. 6 is a side view corresponding to FIG. 4 in a state where the angle of the wire electrode is inclined with respect to FIG. 4;

FIG. 7 is a side view corresponding to FIG. 4 in a state where the speed of the wire electrode is increased with respect to FIG. 4;

8 is a side view corresponding to FIG. 4 in which a material to be processed is tilted with respect to a vertical wire electrode to adjust the lead angle of a screw thread.

FIG. 9 is a side view corresponding to FIG. 4, in which the angle of the wire electrode with respect to the workpiece is changed in accordance with the relative position between the workpiece and the wire electrode.

FIG. 10 is a side view corresponding to FIG. 4, illustrating a state in which a thread is formed while tilting a wire electrode with respect to a workpiece in which a thread forming portion is cut into a truncated cone shape.

11 is a side view corresponding to FIG. 4, illustrating a state in which a thread is formed on a workpiece having a straight screw forming portion equivalent to FIG. 1 while tilting a wire electrode.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Workpiece material 2 Thread formation part 3 Thread 4 Artificial tooth root 5 Head 6 Neck 7 Discharge mark 8 Rotation indexing device 9 Chuck 10 Wire electrode 11 Rod electrode

Claims (5)

[Claims] 1. A workpiece to be a screw-type artificial tooth is rotated, a discharge electrode of an electric discharge machine is brought close to a thread forming portion of the workpiece, and the discharge electrode and the workpiece are rotated. A method for manufacturing an artificial tooth root, wherein a thread is cut in the screw forming portion while being relatively moved in an axial direction. 2. The artificial tooth root manufacturing according to claim 1, wherein the relative speed between the screw forming portion and the discharge electrode is made variable in accordance with the relative position of the discharge electrode and the workpiece in the rotation axis direction. Method. 3. The method according to claim 1, wherein the angle of the discharge electrode with respect to the thread forming portion is made variable in accordance with the relative position of the discharge electrode and the workpiece in the rotation axis direction. 4. The method according to claim 1, wherein the approach distance of the discharge electrode to the screw forming portion is made variable in accordance with the relative position of the discharge electrode and the workpiece in the rotation axis direction. . 5. An artificial tooth root of a screw type,
An artificial tooth root characterized in that the surface of the screw forming part has a matte surface.