JPS61131739A - Dental parallelism forming device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a dental parallelizer, and in particular, to a dental parallelizer, which is configured to issue an alarm when the axis of the grinder and the axis of the abutment tooth deviate from parallelism by more than a certain angle. The present invention relates to a dental parallelizer.

[Conventional technology]

Abutment tooth preparation is an important basic technique in manufacturing a crown prosthesis, and involves providing an appropriate taper to the side wall of the abutment tooth. Generally, the taper that should be applied to the side wall of the abutment tooth is approximately 5 to 10 degrees with respect to the axis of the abutment tooth. Usually, it has a taper of 5 to 10 degrees, and the abutment tooth can be cut as described above simply by moving the handpiece to which the grinder is attached parallel to the abutment tooth.

An example of a conventional dental parallelizer of this type will be explained with reference to FIG. In the conventional example shown in FIG. 4, an inclinometer (5) is attached to an arm or hand piece (IA) of an abutment tooth cutter (11) by a clip (3).

The inclined needle (5) can be freely inclined with respect to the handpiece (IA) by the joint portion (4). At the time of starting cutting of the abutment tooth (ST),
After making the axis of the conical grinder (2) attached to the tip of the handpiece (IA) parallel to the axis (Z-Z) of the abutment tooth (ST), make the inclinometer (5) accurately horizontal. .

The inclinometer (5) is of a type that, when tilted at a certain angle or more with respect to a horizontal plane, the conductive liquid inside comes into contact with the electrodes and becomes conductive. Therefore, by connecting an alarm circuit externally, it is possible to connect the shaft of the grinder (2) and the abutment tooth (ST).
) with respect to the axis (Z-Z) exceeds a certain angle, an alarm is issued.

[Problem that the invention seeks to solve]

However, in such conventional dental parallelizers, an alarm is output when the inclinometer (5) is tilted at a certain angle or more with respect to the horizontal plane, so the abutment tooth (ST) side may have moved. When the grinder 《2》 and the abutment tooth (S
It becomes impossible to obtain a correct warning regarding the declination angle between the axes with T). Therefore, after aligning the inclinometer (5) and the abutment tooth (ST) again as described above, the inclinometer (5) is
The disadvantage is that it must be set horizontally, making it difficult to operate.

Also, the inclinometer (5) at the start of cutting the abutment tooth (ST)
The leveling work directly affects the accuracy of the alarm, so
It is necessary to do this as accurately as possible. However, when leveling the inclinometer (6), while holding both the wheels of the grinder (2) and the abutment tooth (ST) parallel to each other, keep an eye on the spirit level attached to the inclinometer (5). The disadvantage is that it is very difficult to operate, and the horizontal accuracy is not very good.

Furthermore, since the alarm level is determined mechanically depending on the relationship between the electrodes in the inclinometer (5) and the conductive liquid, there is also the drawback that it is not possible to set an alarm level that matches the work situation.

[Means for solving problems]

The present invention provides a posture detector that outputs a signal proportional to the inclination angle of both the handpiece (IA) having the grinder (2) of the abutment tooth cutter (1) and the abutment tooth side (PA). By attaching (51) and (52) respectively and taking the difference between the outputs of both posture detectors (51) and (52), the relative inclination angle between the handpiece and the abutment tooth side is calculated, and the corresponding signal is In addition, a reset switch (6) is provided to memorize the relative inclination angle between the handpiece and the abutment tooth side at the time when this reset switch is activated. By calculating the difference between the relative inclination angle and the stored relative inclination angle, a declination signal of the relative inclination angle between the handpiece and the abutment tooth side from the time when the reset switch is activated is outputted, A dental parallelizer is provided that detects whether or not this deflection angle signal exceeds a predetermined level.

[Effect]

The dental parallel prosthesis of the present invention includes a posture detector such as a two-axis tilted needle that outputs a signal proportional to the tilt angle of both the handpiece (IA) and the abutment tooth side (PA). Attach the handpiece (IA) and abutment tooth side (P) respectively.
Calculate the relative angle between A) and memorize the relative angle between the two at the start of cutting the abutment tooth (ST), and check whether the deviation angle between the two from there is greater than a certain angle. The above-mentioned problem is solved by detecting the above-mentioned condition and issuing an alarm or stopping the drive source of the grinder (2) when the condition exceeds the limit.

〔Example〕

Hereinafter, the present invention will be explained based on the drawings.

FIG. 1 is a route map showing one embodiment of the present invention. First, its configuration will be explained. (1) shows the cutter for the abutment tooth as a whole, (IA) is its arm or handpiece, and (2) is a conical grinder attached to the tip of the handpiece (IA). (51) is a handpiece (
The attitude detector attached to the handpiece (IA) is, for example, a two-axis inclinometer, and can be tilted freely with respect to the handpiece (IA).

(52), for example, when attaching glasses (SP), etc., the abutment tooth (ST) is attached to the patient (hereinafter referred to as the abutment tooth side (PA)) through a tool, for example, with two shafts. It is a posture detector like an inclinometer, and can be freely deposited and tilted with respect to the abutment tooth side (PA). The outputs of the inclinometers (51) and (52) are sent to a control circuit (7).

(6) is a reset switch provided on the handpiece (IA), and when this reset switch (6) is activated, a reset signal is sent to the control circuit (7). Note that the reset switch (6) is connected to the control circuit (7).
It may be set in

Next, the operation of the embodiment of the present invention shown in FIG. 1 will be explained.

First, the inclinometer (52) attached to the abutment tooth side (PA) is made approximately horizontal in advance. Next, use the grinder (
Attach and adjust the inclinometer (52) to the handpiece (IA) so that it is approximately horizontal when the axis of 2) is approximately parallel to the axis (Z-Z) of the abutment tooth (ST). Inclinometer (
51) and (52) are both 2, as mentioned above, for example.
It is a tilted needle with a shaft that outputs a signal proportional to the tilt angle in the X direction and the Y direction, which are orthogonal to each other.

The control circuit (7) calculates the relative inclination angle between the hand piece (IA) and the abutment tooth side (PA) using the signals sent from the inclination needle (5) and (52).

At the time of starting cutting of the abutment tooth (ST), the grinder (
After making the axis of 2) parallel to the axis (Z-Z'') of the abutment tooth (ST), when the reset switch (6) is activated, a reset signal is sent to the control circuit (7), and the control circuit (7)
is the handpiece (IA) and abutment tooth side (PA) at that point.
) and memorize the relative inclination angle. Subsequent abutment tooth (ST)
During the cutting operation, the control circuit (7) controls the relative inclination angle between the handpiece (IA) and the abutment tooth side (PA) to match that of the handpiece (IA) and the abutment tooth side (PA) stored at the time of reset.
Calculate the declination angle between the axis of the grinder (2) and the axis (Z-Z) of the abutment tooth (ST) isometrically by calculating how much it has changed from the relative inclination angle with PA). . Furthermore,
The control device (7) issues an alarm when the calculated deviation angle between the axis of the grinder [2] and the axis (Z-Z) of the abutment tooth (ST) exceeds a predetermined level (angle). It looks like this. Incidentally, at the same time as issuing this alarm, or instead of issuing the alarm, the drive source of the cutting machine (grinder (2) of 11) may be stopped.

Next, an example of the control circuit (7) of the present invention will be explained with reference to FIG.

First, its configuration will be explained. An adder circuit (71X) in the control circuit (7) indicated by a dashed-dotted line block generates an inclination signal (51X) in the X direction of the inclination needle (51) attached to the handpiece (IA) and the abutment tooth side (PA). ) is received in the X direction inclination signal (52X) of the inclination needle (52) attached to Outputs the angle signal. The addition circuit (71Y) receives a tilt signal (51Y) in the Y direction of the tiltmeter (51) attached to the handpiece (IA).
) and an inclinometer (52) attached to the abutment tooth side (PA)
The Y-direction tilt signal (52Y) is received, the difference between the two is taken, and the hand pie is calculated.

A relative inclination angle signal in the Y direction between the base (IA) and the abutment tooth side (PA) is output.

(72K) and (72Y) are husband**-rule) circuits, which receive the reset signal (61) from the reset switch (6).
) is input, the outputs of the adder circuits (71X) and (71Y) at that time are stored and output.

(73X) and (73Y) are adder circuits, respectively, which receive the output signals of the hold circuits (72X) and (72Y) and the output signals of the adder circuits (71X) and (71Y). Output the difference between them. (74X) and (
74Y) are filter circuits, and the adder circuit (74Y) is a filter circuit.
Filter the outputs of (3X) and (73Y). (75
) is a time constant setting circuit that sets each filter time constant of the filter circuits (74X) and (74Y). (76
) is an alarm circuit that receives the outputs of the filter circuits (74X) and (74Y''), and outputs an alarm when at least one of them exceeds the level set by the alarm level setting circuit (77). Also, the drive source of the grinder (2) of the cutting tool (1) may be stopped at the same time as the alarm is output, or instead of outputting the alarm. (78X) and (7
8Y) are indicators, and these are filter circuits (7Y).
The handpiece (I) which is the output of (4X) and (74Y)
A) and the relative inclination angle in the X and Y directions at the time when the reset switch (6) on the abutment tooth side (PA) is activated, and the relative inclination angle in the X and Y directions during cutting work after that point. Display the declination angle with.

Next, the operation of the control circuit (7) will be explained.

First, the inclinometer (
51) and an inclinometer attached to the abutment tooth side (PA) (
52) are kept approximately horizontal as described above. At the start of cutting the abutment tooth (ST), the /'t piece (
After the axis of the grinder (2) attached to IA) and the axis (Z-Z) of the abutment tooth (ST) are made parallel, the reset switch (6) is activated. At this time, the reset switch (6) sends the reset signal (61) to both hold circuits (
72X) and (72Y), and store the outputs of the adder circuits (71X'') and (71Y) at that time.

On the other hand, the addition circuit (71X) is connected to the handpiece (IA)
The tilt signal in the X direction of the tilt meter (51) attached to the
51X) and the inclination signal (52X) in the X direction of the inclinometer (52) attached to the abutment tooth side (PA),
The relative inclination angle in the X direction between the handpiece (IA) and the abutment tooth side (PA) is constantly calculated and a corresponding signal is output. Similarly, the adder circuit (71Y) is connected to the handpiece (IA).
The relative inclination angle in the Y direction between the abutment tooth side (PA) and the abutment tooth side (PA) is constantly calculated and a corresponding signal is output. Therefore, the hold circuit (
72X) and (72Y) are the respective values at the time when the reset switch (6) is activated (i.e., when the axis of the grinder (2) and the axis (Z-Z) of the abutment tooth (ST) become parallel). Handpiece (IA) and abutment tooth side (PA)
This means that the relative inclination angle signals in the X direction and Y direction with respect to the above are stored.

Next, the adder circuits (73X) and (73Y) are connected to the above hold circuits (72X) and (72Y), respectively.
By taking the difference between the output of the adder circuit (71X) and the output of the adder circuit (71Y), the handpiece (IA) and the abutment tooth side (P
A), that is, signal components in the X and Y directions of the deviation angle between the axis of the grinder (2) and the axis (Z-Z) of the abutment tooth (ST) are output.

Therefore, at the time of starting cutting of the abutment tooth (ST), by simply operating the reset switch (6), the axis of the grinder (2) and the axis of the abutment tooth (ST) (Z-Z'
) can always be obtained with high precision.

Filter circuit (74 and Y-direction declination signals are filtered to remove high frequency components due to disturbance vibrations, etc., to obtain correct declination signals, and to provide an appropriate delay time for alarm detection by the alarm circuit (76). Both filter circuits (74X),
The time constant setting circuit (75) of (74Y) is a circuit that sets the filter time constants of the filter circuits (74X) and (74Y) to a desired value, and adjusts the appropriate alarm detection response time according to the work situation. This is for selecting.

The alarm circuit (76) connects the shaft of the grinder (2) and the abutment tooth (
When the declination angle with respect to the axis (Z-Z) of ST) exceeds a predetermined alarm level, an alarm is output, and either the filter circuit (74X) or (74Y) is connected to the alarm level setting circuit ( If the level set by 77) is exceeded, an alarm is output. Alarm level setting circuit (77
) allows the user to freely set the alarm level, for example, when training for abutment tooth preparation, the alarm level can be selected according to the skill of each trainee, increasing the training effect. I can do it.

Note that the alarm circuit (76) synthesizes the outputs of the filter circuits (74X) and (74Y) and detects the magnitude of the declination angle between the axis of the grinder (2) and the axis CZ-Z of the abutment tooth (ST). An alarm may be output when the temperature exceeds the alarm level.

Indicators (78X) and (78Y) indicate the outputs of the filter circuits (74X) and (74Y), respectively, that is, the declination angle between the axis of the grinder (2) and the axis (Z-Z) of the abutment tooth (ST). The X-direction component and Y-direction component of the image are displayed. The display method is not particularly limited, but for example, numerical values, L
Display with ED, bar graph, meter, etc. By using this display, for example, the grinder (
The instructor can constantly monitor the declination angle between the axis of 2) and the axis of the abutment tooth (ST), thereby increasing the teaching effect.

Note that the display circuits (78X) and (78Y) display the declination angle between the axis of the grinder (2) and the axis of the abutment tooth (ST) without using the filter circuits (74X) and (74Y). Addition circuit (73X) and C13't)
It may be displayed using the output of
Filter circuit (74X) for the output of X) and (73Y)
and (74Y) may be displayed through a different filter circuit.

FIG. 3 shows another embodiment of the control circuit (7) of the present invention.

In the example of FIG. 3, the adder circuits (71X) and (71
Y) calculates the difference between the output of the tilt needle (51) attached to the handpiece (IA) and the output of the inclinometer (52) attached to the abutment tooth side (PA), and calculates the difference between the output and the hold circuit. Using (72X), (72Y) and adder circuits (73X") and (73Y), the declination angle between the axis of the grinder (2) and the axis (Z-Z) of the abutment tooth (ST) is obtained. is exactly the same as the embodiment shown in FIG.

Now, in the example of FIG. 3, the display circuit (78X) and (78X)
Y) are the adder circuits (73X) and (73Y), respectively.
output, that is, the shaft of the grinder (2) and the abutment tooth (ST>
This is for displaying the X-direction and Y-direction components of the declination angle with respect to the axis (Z-Z), and is exactly the same as the embodiment shown in FIG. 2, except that it does not use a filter circuit.

In FIG. 3, (79) is an angle synthesis circuit, which inputs the outputs of adder circuits (73X) and (73Y).
The shaft of the grinder (2) and the shaft of the abutment tooth (ST) (Z-Z
) and outputs the absolute value of the argument. In addition, in the example of FIG. 3, one filter circuit (74) is used to filter the output of the angle synthesis circuit (79),
High frequency components caused by external vibrations are removed, and an appropriate delay time is provided for alarm detection. Further, (75) is a time constant setting circuit for setting the filter time constant of the filter circuit (74). (76) is an alarm circuit which receives the output of the filter circuit (74) and outputs an alarm when the output exceeds the level set by the alarm level setting plane (77).

〔Effect of the invention〕

As explained above, according to the present invention, the following effects can be obtained.

(1) By also attaching an inclinometer to the abutment tooth side, even if the abutment tooth side moves, the true declination angle between the axis of the grinder and the axis of the abutment tooth can be obtained.

(2) At the start of cutting the abutment tooth, by simply activating the reset switch, the accurate declination angle between the axis of the grinder and the axis of the abutment tooth can be obtained, making it possible to accurately level the inclined needle like in the past. All operations are no longer necessary, greatly improving operability.

(3) By passing the declination signal between the axis of the grinder and the axis of the abutment tooth through a filter circuit whose time constant can be set arbitrarily, high frequency components caused by external vibrations are removed and a correct declination signal is obtained. , the response time for alarm detection can be selected according to the work situation.

(4) By making it possible to freely set the alarm level, for example, when training for abutment tooth preparation, it is possible to set the alarm level according to the skill of each trainee, and the training effect can be increased.

(5) By providing a display that displays the declination angle between the axis of the grinder and the axis of the abutment tooth, the instructor can constantly monitor the work status of the trainee during training for abutment tooth formation.

[Brief explanation of the drawing]

Fig. 1 is a route diagram of an example of a dental parallelizer according to the present invention, Fig. 2 is a block diagram of an example of its control circuit, Fig. 3 is a block diagram of another example of the control circuit, and Fig. 4 is a conventional FIG. 2 is a route map of an example of a dental parallelizer. In the figure, (1) is a cutter, (IA) is a handpiece, (2) is a grinder, (6) is a reset switch, (
7) is a control circuit, (51), (52) are attitude detectors, (71X), (71Y), (73X
), (73Y) is an adder circuit, (72X),
(72Y) is a hold circuit, (74), (7
4X), (74Y) are filter circuits, (75) are time constant setting circuits, (76) are alarm circuits, (77) are alarm level setting circuits, (78X), (78Y) are indicators, (79) are Angle synthesis circuit, (ST) is the abutment tooth,
(P^) indicates the abutment tooth side, and (SP) indicates the glasses. Figure 4 Procedural Amendment April 16, 1985 1. Indication of Case 1988 Patent Application No. 244883 2° Invention +
7) Name 4ゞ1゛ Dental parallelizer 3, relationship with the case of the person making the correction Patent applicant address 2-16-46 Minami Kamata, Ota-ku, Tokyo Name (338) Tokyo Keiki Co., Ltd. 4. Agent 6, 7! Number of inventions increased by i addition 7, subject of amendment Detailed description of the invention in Mei 811I (1) In the specification, page 8, line 14 "Inclinometer (52) J
Correct it as r (Ql inclination meter (51) J). (21, page 1O, line 9, correct “the difference between both” to “the difference between both”. (3) Same, page 15, line 9. Correct "output signal of r(71Y)" to "output signal of r(71Y)" in line 41. (Correct ``Save during training'' on page 15, line 1 of 41 to ``during training.'')

Claims (1)

[Claims] 1. Attachment detectors that output signals proportional to the inclination angles of both the handpiece having the grinder and the abutment tooth side of the abutment tooth cutter are respectively attached, By taking the difference in the outputs of the detectors, the relative inclination angle between the handpiece and the abutment tooth side is calculated, and a corresponding signal is output.A reset switch is provided, and when the reset switch is activated, The reset switch is activated by storing the relative inclination angle between the handpiece and the abutment tooth side, and calculating the difference between the relative inclination angle between the handpiece and the abutment tooth side and the stored relative inclination angle. A declination signal of the relative inclination angle between the handpiece and the abutment tooth side from the point in time when the declination angle signal exceeds a predetermined level is detected. A dental parallelizer. 2. The dental parallelizer according to claim 1, wherein an alarm is issued when the declination signal exceeds a predetermined level. 3. The dental parallelizer according to claim 1, wherein the drive source for the grinder is stopped when the deviation angle signal exceeds a predetermined level. 4. The declination signal from the time when the reset switch for the relative inclination angle between the handpiece and the abutment tooth side is activated is passed through a filter circuit to provide an appropriate delay time for alarm detection. The dental parallelizer according to claim 2, characterized in that the time constant can be set arbitrarily, so that the response time for alarm detection can be freely selected. 5. The dental parallelizer according to claim 2, wherein the level of the alarm generation can be arbitrarily set. 6. Claim 1, characterized in that the declination signal from the time when the reset switch for the relative inclination angle between the handpiece and the abutment tooth side is activated is displayed by a display device. Dental parallelizer as described in section.