KR101616551B1 - Orthodontic simulation device, method for automatically adjusting tooth projecting angle in orthodontic simulation device, and computer readable record medium storing the same - Google Patents

Abstract

The present invention relates to an orthodontic simulation device, a method for automatically adjusting tooth projecting angle in an orthodontic simulation device, and a computer readable recording medium storing the same. The method for automatically adjusting tooth projecting angle in an orthodontic simulation device comprises the steps of: obtaining each tooth rotating shaft information and a central pointing information from tooth object data; changing a rotational shaft angle with respect to a first object data of the tooth object data; and automatically arranging a rotational shaft angle of a second tooth object using the changed rotational shaft angle and specific set angle of each tooth.

Description

TECHNICAL FIELD [0001] The present invention relates to a dental prosthesis simulation apparatus, a dental prosthesis simulation apparatus, a method of automatically adjusting the dental prosthesis angle, and a computer readable recording medium storing the same. BACKGROUND OF THE INVENTION STORING THE SAME}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dental-orthodontic simulation apparatus, a dental-orthodontic angle automatic adjustment method in a dental-orthodontic simulation apparatus, and a computer-readable recording medium storing the same.

In general, malocclusion refers to malocclusion in which the upper and lower teeth are abnormal in dentition. Such malocclusion not only causes functional problems such as writing and pronunciation problems and aesthetic problems on the face, but also causes tooth decay and gum disease And may cause the same health problems.

Therefore, tooth orthodontic treatment should be performed in order to make such malocclusion into normal occlusion.

Especially at the time of orthodontic treatment, the protruding angle of the anterior teeth (front teeth) is very important for beauty. When the anterior teeth are too protruded, the lips are seen to protrude forward, and the anterior teeth do not protrude, resulting in a drop in the three-dimensional sensation of the face.

These projecting angles are very closely related to human body shape, i.e., obesity. Therefore, the practitioner needs to perform orthodontic correction by adjusting the protruding angle of the teeth according to the taste of the examinee or the body shape.

The present invention relates to a tooth calibration simulation apparatus capable of automatically changing the protruding angle of a tooth so that the examinee and the practitioner can perform orthodontic correction in a desired form in the examination prior to tooth calibration, And a computer-readable recording medium storing the method.

According to an embodiment of the present invention, there is provided a method of automatically adjusting a tooth protrusion angle in a tooth correction simulation apparatus, comprising: setting at least one of tooth standard data and tooth weight data; Obtaining rotational axis information and center point information for each tooth from the tooth object data; Changing a rotation axis angle with respect to a first tooth object of the tooth object data; And automatically aligning the rotation axis angle of the second tooth object using at least one of the changed rotation axis angle and the tooth standard data and the tooth weight data.

Here, the method of automatically adjusting the tooth protrusion angle in the tooth correction simulation apparatus may further include the step of acquiring the tooth object data from the subject tooth structure image data.

Here, the method for automatically adjusting the tooth protrusion angle in the tooth correction simulation apparatus may further include obtaining the tooth profile structure image data from the gypsum model of the examinee.

Here, the method of automatically adjusting the tooth protrusion angle in the orthodontic simulation apparatus may further include acquiring the image data of the examinee's tooth structure through a scanner image of the examinee.

The step of automatically aligning the angle of rotation axis of the second tooth object using at least one of the changed rotation axis angle and the tooth standard data and the tooth weight data may further comprise the step of, when the first tooth object is inverted, May be automatically aligned in accordance with the following Equation (1).

[Formula 1]

X = B / A * C

X: rotation axis angle of the second object that is automatically aligned

A: rotation axis angle of the first object set

B: rotation axis angle of the changed first object

C: rotation axis angle of the set second object

The step of automatically aligning the rotation axis angle of the second tooth object using the changed rotation axis angle and at least one of the tooth standard data and the tooth weight data may include the steps of automatically aligning the rotation axis angle of the second tooth object with the rotation axis angle The rotational axis angle of the second tooth object may be automatically aligned in accordance with the following equation (2).

[Formula 2]

X = D- (D-C) * (D-B) / (D-A)

X: rotational axis angle of the automatically aligned second tooth object

A: rotation axis angle of the first object set

B: rotation axis angle of the changed first object

C: rotation axis angle of the set second object

D: Angle of rotation axis of the preset

[Case where the second object is located between the transpose and the first object]

The step of automatically aligning the rotation axis angle of the second tooth object using the changed rotation axis angle and the setting angle of each tooth may include the steps of, when the first tooth object is not a transposition and the rotation axis angle is fixed with respect to the transposition, And the rotational axis angle of the second tooth object may be automatically aligned according to the following expression (3).

[Formula 3]

X = B / A * C

X: rotation axis angle of the second object that is automatically aligned

A: rotation axis angle of the first object set

B: rotation axis angle of the changed first object

C: rotation axis angle of the set second object

[When the second object is located between the first object and the molar (including the molar)]

Here, the method of automatically adjusting the tooth protrusion angle in the tooth correction simulation apparatus may further include a step of driving a collision program for the automatically aligned tooth object to readjust the automatic aligned tooth objects so that they do not collide with each other .

The step of driving the collision program with respect to the automatically aligned tooth objects so that the automatically aligned tooth objects do not collide with each other includes the steps of setting a setting path connecting the center points of the automatically aligned tooth objects ; Confirming whether the automatically aligned tooth object collides with the object; And allowing one of the tooth objects to be automatically spaced a predetermined distance along the set path if the tooth objects collide with each other

Yet another embodiment of the present invention can provide a computer-readable recording medium having stored thereon a method for automatically adjusting the tooth protrusion angle in the above-described orthodontic simulation apparatus.

A tooth calibration simulation apparatus according to another embodiment of the present invention includes a memory for storing tooth standard data and tooth object data; A user input unit for changing a setting angle of a first tooth object included in the tooth object data; And acquiring the rotation axis information and the center point information for each tooth in the tooth object data and changing the rotation axis angle with respect to the first tooth object by the user input unit, And a controller for automatically aligning the rotation axis angle of the object and displaying the same on the display unit.

Here, the tooth calibration simulation apparatus may further include a scanner for acquiring the subject tooth structure image data, and the control unit may control to generate the tooth object data through the subject tooth structure image data.

Here, when the first tooth object is transposed, the control unit may automatically align the rotation axis angle of the second tooth object according to the following [Equation 1].

[Formula 1]

X = B / A * C

X: rotation axis angle of the second object that is automatically aligned

A: rotation axis angle of the first object set

B: rotation axis angle of the changed first object

C: rotation axis angle of the set second object

Here, when the first tooth object is not transposed but the rotation axis angle is fixed with respect to the transposition, the control unit can automatically align the rotation axis angle of the second tooth object according to the following expression (2).

[Formula 2]

X = D- (D-C) * (D-B) / (D-A)

X: rotational axis angle of the automatically aligned second tooth object

A: rotation axis angle of the first object set

B: rotation axis angle of the changed first object

C: rotation axis angle of the set second object

D: Angle of rotation axis of the preset

[Case where the second object is located between the transpose and the first object]

Here, when the first tooth object is not transposed but the rotation axis angle is fixed with respect to the transposition, the control unit can automatically align the rotation axis angle of the second tooth object according to the following expression (3).

[Formula 3]

X = B / A * C

X: rotation axis angle of the second object that is automatically aligned

A: rotation axis angle of the first object set

B: rotation axis angle of the changed first object

C: rotation axis angle of the set second object

[When the second object is located between the first object and the molar (including the molar)]

According to an embodiment of the present invention having the above-described configuration, when a practitioner performs a simulation of teeth correction for tooth correction of a subject, if the protruding angle is adjusted only for one tooth for which the protrusion angle is to be adjusted, The protruding angle is automatically adjusted and displayed, so that the user convenience is extremely high.

In other words, it is possible to adjust the protruding angle of 28 teeth faster and more accurately than manually adjusting the angle of 28 teeth.

Further, after adjusting the tooth projecting angle, the tooth calibration simulation is executed according to the changed arch, so that it is possible to provide information necessary for selecting an appropriate treatment method.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is an image diagram showing an example of a protruding tooth according to an embodiment of the present invention; Fig.
Fig. 2 is an exploded view of an image of an examinee showing the maxilla and mandible associated with an embodiment of the present invention; Fig.
Fig. 3 is a view for explaining the protruding angle of a tooth according to an embodiment of the present invention; Fig.
FIG. 4 is a flowchart for explaining a method of automatically adjusting a tooth protrusion angle in a tooth correction simulation apparatus, which is an embodiment of the present invention. FIG.
FIG. 5 is a block diagram for explaining an electronic configuration of a denture correction simulation apparatus according to an embodiment of the present invention; FIG.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, in which like reference numerals refer to like elements throughout.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is an image diagram showing an example of a protruding tooth according to an embodiment of the present invention. Fig. As shown in Fig. 1, when the tooth A is protruded, it is necessary to reduce the protruding angle of the tooth A so that the tooth A is protruded, and it is necessary to restrict the occurrence of the ducking.

In this case, when the projecting angle of the tooth A is reduced, the entire size of the arch of the examinee is reduced. As a result, the teeth that did not collide with each other may collide with each other.

However, if you want to check whether the teeth will collide, how much spacing will be needed in case of collision, and what type of correction should be used (extraction method, tooth movement method, etc.) It is necessary to check and adjust.

FIG. 2 is a developed image diagram for showing the maxilla and mandible of a subject in accordance with an embodiment of the present invention. FIG. As shown, the general adult has seven teeth (1-7) on both sides of the anterior teeth (1: front teeth). These teeth are each slightly protruding, and Table 1 below shows an example of tooth standard data.

Rotation axis angle of tooth standard data 7 6 5 4 3 2 One One 2 3 4 5 6 7 Maxilla 0 0 3 3 5 7 10 10 7 5 3 3 0 0 Mandatory 0 One 2 3 4 5 6 6 5 4 3 2 One 0

Here, the numbers represent respective teeth, 1 represents transposition, and 7 represents molar teeth. As illustrated in Table 1, the angles of the mandible and mandible are stored in the memory of the orthodontic simulation apparatus according to the present invention as tooth standard data.

FIG. 3 is a view for explaining the protruding angle of a tooth according to an embodiment of the present invention. FIG. The angle of the rotation axis indicates how much the teeth are inclined with respect to the arch. In Fig. 3, an example of defining the rotation axis angle will be described as an example. The shape of the teeth is shown in Fig. The teeth consist largely of root (b) and crown (c). At this time, a virtual line connecting the center point of the crown (c) to the axis passing through the center point can be defined as the rotational axis (a) with the center point of both ends of both roots (c) as the center point.

In the present invention, the angle of the rotation axis? May mean the angle between the rotation axis a and the vertical plane d in the arch. Here, + angle means that the tooth protrudes forward, and - angle means that the tooth is retracted into the mouth.

The angle of the rotation axis can be defined in various other ways to indicate how much the tooth is inclined relative to the arch.

Hereinafter, a method of automatically adjusting the tooth protrusion angle in the orthodontic appliance according to the present invention will be described in detail with reference to FIG.

FIG. 4 is a flowchart for explaining a method of automatically adjusting the tooth protrusion angle in the orthodontic simulation apparatus, which is an embodiment of the present invention. As shown in FIG. 4, first, tooth standard data is stored in a memory (S1). An example of the tooth standard data is described above. The tooth standard data may exist in various forms in consideration of the examinee's age, gender, body weight, etc. rather than storing only one example.

 Then, tooth object data is obtained (S3). The tooth object data is obtained by objectizing only the tooth part in the image data of the subject tooth structure. At this time, the tooth structure image data may be obtained by a scanning method such as a CT scan of the examinee, or may be obtained by creating a plaster model of the examinee.

Then, in the tooth object data, the rotational axis information and the center point information for each tooth are obtained from the tooth object data (S5). This is described above, so it is omitted. Then, primary alignment is performed using the tooth-specific rotation axis information and center-point information and the tooth standard data. That is, primary teeth are rotated in the direction of the central axis and the rotation axis so as to have the same angle as tooth standard data for each tooth (S7). Then, the operator changes the rotation axis angle of the first tooth object (S9). At this time, the first tooth object may be transposed (front teeth), and may not be transposed. The processing method for these will be described later.

In addition, primary alignment may be performed using tooth weight data. That is, each tooth object data of the examinee may be weighted for each tooth, and the primary sorting may proceed accordingly.

 If the rotation axis of the first tooth object is changed through the user input unit, the rotation axis angle of the second tooth object, which is the remaining tooth object, is automatically aligned using the changed rotation axis angle and the tooth standard data or the tooth weight data (S11) .

If the first tooth object is inverted, the rotation axis angle of the second tooth object is automatically aligned according to the following [Equation 1].

[Formula 1]

X = B / A * C

X: rotation axis angle of the second object that is automatically aligned

A: rotation axis angle of the first object set

B: rotation axis angle of the changed first object

C: rotation axis angle of the set second object

Here are some examples.

Table 1 is the rotation axis angle of the primary aligned teeth (tooth object).

Here, when the angle of the first tooth, which is the transposition of the maxilla, is changed to 8 degrees, the rotation axis of the remaining teeth of the maxilla is changed according to the above-mentioned expression (1). The angles of rotation of the changed teeth are changed to the following [Table 2].

Angle of rotation axis changed according to Equation 1 according to change of frontal angle 7 6 5 4 3 2 One One 2 3 4 5 6 7 Maxilla 0 0 2.4 2.4 4 5.6 8 8 5.6 4.0 2.4 2.4 0 0 Mandatory 0 One 2 3 4 5 6 6 5 4 3 2 One 0

If there is a change in the angle of the rotation axis with respect to teeth other than transposition, there are two methods. In the first case, transposition is the case of moving, and the second case is the case of fixing the transposition.

In the first case, for example, when the upper 5th tooth is changed from 3 degrees to 4 degrees in [Table 1], the following table is changed. In this case, it is changed according to [Equation 1].

Angle of rotation axis changed according to equation 1 according to 5th tooth angle change 7 6 5 4 3 2 One One 2 3 4 5 6 7 Maxilla 0 0 4 4 6.5 9.3 13.3 13.3 9.3 6.5 4 4 0 0 Mandatory 0 One 2 3 4 5 6 6 5 4 3 2 One 0

In the second case, when the second object tooth is located between the transpose and the first object tooth, the rotation axis is changed according to the following expression (2).

[Formula 2]

X = D- (D-C) * (D-B) / (D-A)

X: rotational axis angle of the automatically aligned second tooth object

A: rotation axis angle of the first object set

B: rotation axis angle of the changed first object

C: rotation axis angle of the set second object

D: Angle of rotation axis of the preset

If the second tooth object to be automatically aligned is located between the first tooth object and the molar (including molar teeth), it is automatically aligned according to the following expression (3).

[Formula 3]

X = B / A * C

X: rotation axis angle of the second object that is automatically aligned

A: rotation axis angle of the first object set

B: rotation axis angle of the changed first object

C: rotation axis angle of the set second object

[When the second object is located between the first object and the molar (including the molar)]

In this case, when the teeth of the maxillary third tooth are changed from 5 degrees to 4 degrees and the rotation axis angle of the anterior teeth is fixed, the rotation axis is changed as shown in Table 4 below.

Changed angle of rotation axis when prefixed 7 6 5 4 3 2 One One 2 3 4 5 6 7 Maxilla 0 0 2.4 2.4 4 6.4 10 10 6.4 4. 2.4 2.4 0 0 Mandatory 0 One 2 3 4 5 6 6 5 4 3 2 One 0

Thus, when the angle of the rotation axis of one of the tooth objects is changed, the tooth angle object is automatically aligned with the axis of the tooth, so that the operator does not need to change the axis angle one by one.

As the rotation axis angle is changed, the shape and size of the arch are different. Therefore, in this case, since the teeth collide with each other, correction is required.

When the rotation axis alignment is completed, the collision program is driven on the automatically aligned tooth objects to readjust the misaligned tooth objects so that they do not collide with each other. That is, a setting path connecting the center points of the automatically aligned tooth objects is set, and the presence or absence of collision of the automatically aligned tooth objects is checked. If the teeth objects collide with each other, So that it is possible to propose a method of orthodontic treatment. In other words, it is possible to know whether or not teeth should be calibrated by extracting teeth, and whether teeth can be sufficiently calibrated through tooth movement.

5 is a block diagram for explaining an electronic configuration of a denture correction simulation apparatus according to an embodiment of the present invention. 5, the orthodontic appliance simulation apparatus 100 according to an embodiment of the present invention includes a memory 110, a user input unit 120, a scanner 130, a display unit 140, and a controller 150 And the like.

The memory 110 is a component for storing tooth standard data and tooth object data. The memory 110 may be a flash memory type, a hard disk type, a multimedia card micro type, a card type memory (for example, SD or XD memory) (Random Access Memory), a static random access memory (SRAM), a read-only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), a programmable read-only memory (PROM) A magnetic disk, and / or an optical disk.

The user input unit 120 is for receiving an input signal and inputs a signal for changing a setting angle of a first tooth object included in the tooth object data. The user input unit 120 may be a key button, a mouse, a keyboard, a touch screen, or the like.

The scanner 130 is a component for acquiring the image data of the recipient tooth structure of the examinee. The scanner 130 is a component for optically acquiring tooth structure image data of the examinee, such as a CT apparatus or an oral scanner.

 The display unit 140 displays (outputs) the information processed by the controller of the orthodontic simulation apparatus according to the present invention. That is, the image processing apparatus displays the subject tooth structure image data, displays the tooth object data obtained through the subject tooth structure image data, and displays the automatically aligned tooth structure image data. In addition, a UI for changing a tooth object is displayed.

The display unit 140 may be a liquid crystal display (LCD), a thin film transistor-liquid crystal display (TFT LCD), an organic light-emitting diode (OLED), a flexible display display, and a 3D display.

The control unit 150 obtains the rotation axis information and the center point information for each tooth from the tooth object data and changes the rotation axis angle for the first tooth object by the user input unit, To automatically align the rotation axis angle of the second tooth object. That is, the function of controlling the tooth object data is generated through the subject tooth structure image data acquired through the scanner. The operation of these control units has been described with reference to FIG. 4, and a description thereof will be omitted.

Further, according to an embodiment of the present invention, the above-described method can be implemented as a code that can be read by a processor on a medium on which the program is recorded. That is, the method of automatically adjusting the tooth protrusion angle in the above-described orthodontic appliance can be stored in a computer-readable recording medium. Examples of the medium that can be read by the processor include ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical data storage, etc., and may be implemented in the form of a carrier wave (e.g., transmission over the Internet) .

According to an embodiment of the present invention having the above-described configuration, when a practitioner performs a simulation of teeth correction for tooth correction of a subject, if the protruding angle is adjusted only for one tooth for which the protrusion angle is to be adjusted, The protruding angle is automatically adjusted and displayed, so that the user convenience is extremely high.

Further, after adjusting the tooth projecting angle, the tooth calibration simulation is executed according to the changed arch, so that it is possible to provide information necessary for selecting an appropriate treatment method.

The above-described teeth correction simulation apparatus, a method of automatically adjusting the tooth projection angle in the orthodontic simulation apparatus, and a computer-readable recording medium storing the same can be applied to a configuration and a method of the above- Alternatively, all or some of the embodiments may be selectively combined so that various modifications of the embodiments can be made.

100: Orthodontic simulation apparatus
110: Memory
120: user input section
130: Scanner
140:
150:

Claims (15)

Setting at least one of tooth standard data and tooth weight data;
Obtaining rotational axis information and center point information for each tooth from the tooth object data;
Changing a rotation axis angle with respect to a first tooth object of the tooth object data; And
And automatically aligning the rotational axis angle of the second tooth object using the modified rotation axis angle and at least one of the tooth standard data and the tooth weight data.
The method according to claim 1,
Further comprising the step of acquiring the tooth object data from the subject tooth structure image data.
3. The method of claim 2,
Further comprising the step of acquiring the subject tooth structure image data from a plaster model of the subject.
3. The method of claim 2,
Further comprising the step of acquiring the subject tooth structure image data through a scanner photographing of the subject.
The method according to claim 1,
The step of automatically aligning the rotation axis angle of the second tooth object using the changed rotation axis angle and at least one of the tooth standard data and the tooth weight data,
Wherein when the first tooth object is inverted, the rotation axis angle of the second tooth object is automatically aligned in accordance with the following equation (1): " (1) "
[Formula 1]
X = B / A * C
X: rotation axis angle of the second object that is automatically aligned
A: rotation axis angle of the first object set
B: rotation axis angle of the changed first object
C: rotation axis angle of the set second object
The method according to claim 1,
The step of automatically aligning the rotation axis angle of the second tooth object using the changed rotation axis angle and at least one of the tooth standard data and the tooth weight data,
Wherein the angle of rotation of the second tooth object is automatically aligned according to the following formula 2 when the first tooth object is not transposed and the angle of rotation axis is fixed with respect to the transposition. A method of automatically adjusting an angle of protrusion of a tooth of a tooth.
[Formula 2]
X = D- (DC) * (DB) / (DA)
X: rotational axis angle of the automatically aligned second tooth object
A: rotation axis angle of the first object set
B: rotation axis angle of the changed first object
C: rotation axis angle of the set second object
D: Angle of rotation axis of the preset
[Case where the second object is located between the transpose and the first object]
The method according to claim 6,
The step of automatically aligning the rotation axis angle of the second tooth object using the changed rotation axis angle and at least one of the tooth standard data and the tooth weight data,
Wherein the angle of rotation of the second tooth object is automatically aligned according to the following formula 3 when the first tooth object is not transposed and the rotation axis angle is fixed with respect to the transposition A method of automatically adjusting an angle of protrusion of a tooth of a tooth.
[Formula 3]
X = B / A * C
X: rotation axis angle of the second object that is automatically aligned
A: rotation axis angle of the first object set
B: rotation axis angle of the changed first object
C: rotation axis angle of the set second object
[When the second object is located between the first object and the molar (including the molar)]
The method according to claim 1,
Further comprising driving a collision program for the automatically aligned tooth object to recalibrate the automatically aligned tooth objects so that they do not collide with each other.
9. The method of claim 8,
The step of driving the collision program for the automatically aligned tooth objects such that the automatically aligned tooth objects do not collide with each other,
Setting a set path connecting the center points of the automatically aligned tooth objects;
Confirming whether the automatically aligned tooth object collides with the object; And
And automatically causing one of the tooth objects to be spaced apart a predetermined distance along the set path if the teeth objects collide with each other.
A computer-readable recording medium having stored thereon a method for automatically adjusting a tooth projecting angle in the orthodontic appliance according to any one of claims 1 to 9.
A memory for storing tooth object data and at least one of tooth standard data and tooth weight data;
A user input unit for changing a setting angle of a first tooth object included in the tooth object data;
A display unit for displaying the tooth object data; And
The method of claim 1, further comprising: obtaining rotation axis information and center point information for each tooth in the tooth object data, and changing the rotation axis angle for the first tooth object by the user input unit, And a control unit for automatically aligning the angle of the rotation axis of the second tooth object using the display unit and displaying the same on the display unit.
12. The method of claim 11,
Further comprising a scanner for acquiring the subject tooth structure image data,
Wherein,
And controls to generate the tooth object data through the subject tooth structure image data.
12. The method of claim 11,
Wherein,
And automatically aligns the rotation axis angle of the second tooth object according to the following formula 1 when the first tooth object is transposed.
[Formula 1]
X = B / A * C
X: rotation axis angle of the second object that is automatically aligned
A: rotation axis angle of the first object set
B: rotation axis angle of the changed first object
C: rotation axis angle of the set second object
12. The method of claim 11,
Wherein,
Wherein the rotational axis angle of the second tooth object is automatically aligned in accordance with the following expression (2) when the first tooth object is not a transposition and the rotation axis angle is fixed with respect to the transposition.
[Formula 2]
X = D- (DC) * (DB) / (DA)
X: rotational axis angle of the automatically aligned second tooth object
A: rotation axis angle of the first object set
B: rotation axis angle of the changed first object
C: rotation axis angle of the set second object
D: Angle of rotation axis of the preset
[Case where the second object is located between the transpose and the first object]
12. The method of claim 11,
Wherein,
Wherein the rotational axis angle of the second tooth object is automatically aligned in accordance with the following expression (3) when the first tooth object is not a transposition and the rotation axis angle is fixed with respect to the transposition.
[Formula 3]
X = B / A * C
X: rotation axis angle of the second object that is automatically aligned
A: rotation axis angle of the first object set
B: rotation axis angle of the changed first object
C: rotation axis angle of the set second object
[When the second object is located between the first object and the molar (including the molar)]

Images