KR102040099B1 - Apparatus and method for determining area of detal implant placement - Google Patents

Abstract

According to an embodiment of the present invention, the tooth region including the tooth, the maxillary sinus, the alveolar bone / cortical bone, and the lower alveolar neural tube from the CT image of the tooth is selected, and after selecting the position of the lost tooth using the dental arch, The implant procedure can be performed more accurately and efficiently by automatically and accurately calculating the implantation position, implantation angle, and depth of the implant tooth so as not to damage the neural tube.

Description

Apparatus and method for selecting implant implantation area {APPARATUS AND METHOD FOR DETERMINING AREA OF DETAL IMPLANT PLACEMENT}

The present invention relates to the selection of the implantation implantation area, in particular, by extracting the tooth region and the features of the teeth from the CT image of the teeth to automatically select the implantation region to be implanted implantation can be performed more accurately and efficiently The present invention relates to a device and method for selecting an implant placement area.

In general, unlike an X-ray apparatus for obtaining a 2D plane image, the CT apparatus may acquire a stereoscopic image of the inside of the patient's body using an X-ray projection apparatus that rotates about the patient. For example, the CT device may acquire a 2D cross-sectional image of the patient's body and then combine the cross-sectional images to form a 3D image.

On the other hand, when a tooth is lost, a tooth is generally used to recover the lost tooth using the surrounding tooth, or when the tooth is poor, the implant is usually used.

The placement of such implants varies greatly from patient to patient, since the implantation position of the implant should be determined by various factors such as the patient's tooth condition, the position of the tooth requiring the implant procedure, and the condition of the patient's alveolar bone. The implantation position, depth and direction of the implant are determined by considering various factors of each patient as described above, which should be carefully determined in consideration of the characteristics of the patient.

Conventionally, in order to determine the implantation position of the implant, it was common to obtain an alveolar bone image of a patient using an imaging device such as CT and determine the implantation position and orientation of the implant based on the experience of the operator.

However, the conventional method has a problem in that the implant placement position, direction, depth, etc. cannot be accurately derived when the tooth region or the tooth feature cannot be accurately analyzed from the CT image.

In addition, in the case of determining the implantation position, etc. in view of the experience of the operator, the implantation position may be wrong in the case of a patient having unusual tooth characteristics, and thus it was difficult to set the implant placement position optimally.

(Patent literature)

Republic of Korea Patent No. 10-1163808 (Registration date July 02, 2012)

Therefore, in an embodiment of the present invention, the implant is extracted from the CT image of the tooth, and the implant is extracted so that the implant procedure can be performed more accurately and efficiently by automatically selecting an implantation region to be implanted. An apparatus and method for selecting an implantation area are provided.

An implant placement area selection apparatus according to an embodiment of the present invention described above, comprising: a tooth region division unit for receiving a CT image photographing a tooth and dividing the tooth region from the CT image, based on information about the tooth region; Detecting the occlusal plane of the maxillary and the mandibular teeth, a tooth feature extracting unit for calculating the maxillary and the mandibular arches of the mandibular dentition, the location of the tooth region and the maxillary or mandibular dental loss, And an implant implantation region selector for selecting an implantation region of the implant tooth to be implanted at the position of the lost tooth.

The tooth feature extracting unit may set an initial occlusal plane that crosses the maxillary or lower jaw dentition by setting a sample point of the maxillary or mandibular dentition, and connects the sample points to the first occlusal plane. In the order of teeth spaced far apart, after selecting a plurality of teeth it is characterized in that to calculate the occlusal plane by connecting the ends of the plurality of teeth.

The tooth feature extractor may further include: an intersection point at which the occlusal plane moved after the occlusal plane is spaced apart by a predetermined distance from an upper portion of the maxillary teeth or a lower portion of the mandibular teeth to cross the maxillary teeth or the mandibular teeth. ), And the arch form is generated by generating a curve passing through the intersection point through a curve approximation.

In addition, the implant placement area selector, the first dental arch located in the occlusal plane and the second dental arch located at a predetermined distance moving in the tooth direction from the occlusal plane, and using the first dental arch the lost tooth Obtaining a point of intersection between two adjacent teeth located on both sides of the first dental arch and finding the two points forming the minimum distance between the two adjacent teeth, wherein the first dental arch is closest to the center point between the two points; After extracting one point, finding a second point of the second dental arch form closest to the first point and calculating a vector connecting the first point and the second point, the vector is the maxillary or lower jaw. It is characterized in that the intersection point intersects with the alveolar bone is selected as the implantation position of the implant tooth.

In addition, the implant placement region selection unit is characterized in that for selecting the angle of the vector forming the occlusal plane as the implantation angle of the implant teeth.

The implant implantation region selector may be configured to calculate an average value of angles formed by a plurality of predetermined teeth around the lost tooth and the occlusal plane, and select the average value as an implantation angle of the implant tooth.

The implant implantation region selector may generate an implantation shape of the implant tooth by using the implantation position, the implantation angle, and the minimum distance between both teeth of the lost tooth.

In addition, the implant placement area selector, the shape of the implant tooth is formed in the form of the two cylinders are connected, and generates a first cylinder of the two cylinders in the insertion position, when the missing tooth is the first A diameter of one cylinder is formed to a length corresponding to the minimum distance between two teeth adjacent to the lost tooth, and a second cylinder is created to be connected to the first cylinder in the cortical bone area of the implantation position, but the diameter of the second cylinder It characterized in that to form smaller than the diameter of the first cylinder.

In addition, the implant placement area selector, the shape of the implant tooth is generated in the form of the two cylinders are connected, the first cylinder of the two cylinders in the insertion position, if the missing teeth are two or more A distance obtained by dividing the minimum distance between two adjacent teeth by the number of the lost teeth by the diameter of the first cylinder and generating a second cylinder to be connected to the first cylinder in the cortical bone area of the implantation position The diameter of the second cylinder is characterized in that the smaller than the diameter of the first cylinder.

In addition, the implant placement region selector, characterized in that for forming the length of the first cylinder to the average length of a plurality of predetermined teeth around the lost tooth.

In addition, the implant placement region selector, characterized in that for forming the length of the second cylinder to the average value of the length of the root length of the plurality of teeth around the lost tooth.

In addition, as a method for selecting an implant placement region according to an embodiment of the present invention, receiving a CT image photographing a tooth, dividing a tooth region from the CT image, and the maxillary dentition based on information on the tooth region And calculating the occlusal plane of the mandibular dentition and the dental arch of the maxillary and mandibular dentition, detecting the position of the maxillary or mandibular missing tooth, and the implant to be placed at the position of the missing tooth. Selecting an implantation region of the tooth.

The calculating of the occlusal plane may include setting a sample point of the maxillary or mandibular teeth and selecting an initial occlusal plane across the maxillary or mandibular teeth by connecting the sample points. And calculating the occlusal plane by connecting the ends of the plurality of teeth after selecting the plurality of teeth in order of the teeth spaced farthest from the initial occlusal plane.

The calculating of the arch form may include: moving the occlusal plane to an upper portion of the maxillary dentition or to a lower portion of the mandibular dentition by a predetermined distance, wherein the moved occlusal plane intersects the maxillary dentition or the mandibular dentition. Obtaining an intersection point, and generating the arch form by generating a curve passing through the intersection point through curve approximation.

The step of selecting the implantation region may include calculating a first dental arch located on the occlusal plane and a second dental arch positioned at a predetermined distance in the tooth direction from the occlusal plane; Obtaining an intersection point between two adjacent teeth located on both sides of the lost tooth and the first arch form, and finding two points that form a minimum distance between the two adjacent teeth using a center point and the most Extracting the first first arch arch first point close to each other, finding the second second arch arch point closest to the first point and calculating a vector connecting the first point and the second point; And selecting an intersection where the vector intersects the alveolar bone of the maxillary dentition or the mandibular dentition as the implantation position.

The selecting of the implantation region may further include selecting an angle between the vector and the occlusal plane as an implantation angle of the implant tooth.

The selecting of the implantation angle may include calculating an average value of an angle formed by a plurality of predetermined teeth around the lost tooth and the occlusal plane, and selecting the average value as an implantation angle of the implant tooth. It is characterized by including.

The method may further include generating an implantation shape of the implant tooth by using the implantation position, the implantation angle, and the minimum distance between both teeth of the lost tooth.

The generating of the implant may include generating a first cylinder having a diameter of a minimum distance between two adjacent teeth and a diameter at the insertion position when the missing tooth is one; And a second cylinder connected to the first cylinder in the cortical bone region of the second cylinder having a diameter smaller than that of the first cylinder.

The generating of the implant may include placing the first cylinder having a diameter of a distance obtained by dividing the minimum distance between two adjacent teeth by the number of the missing teeth when the missing teeth are two or more. And generating a second cylinder connected to the first cylinder in the cortical bone region of the implantation position and having a diameter smaller than the first cylinder.

In addition, the length of the first cylinder, characterized in that formed in the average length of a plurality of predetermined teeth around the lost tooth.

In addition, the length of the second cylinder, characterized in that formed as the average value of the tooth root length of the plurality of predetermined teeth around the lost tooth.

According to an embodiment of the present invention, the tooth region including the tooth, the maxillary sinus, the alveolar bone / cortical bone, and the lower alveolar neural tube from the CT image of the tooth is selected, and after selecting the position of the lost tooth using the dental arch, The implant procedure can be performed more accurately and efficiently by automatically and accurately calculating the implantation position, implantation angle, and depth of the implant tooth so as not to damage the neural tube.

1 is a detailed block diagram of an implant placement region selection device according to an embodiment of the present invention.
Figure 2 is an illustration of individual tooth segmentation according to an embodiment of the present invention.
Figure 3 is an illustration of individual tooth numbering according to an embodiment of the present invention.
Figure 4 is an illustration of mandibular cortical bone segmentation including alveolar bone according to an embodiment of the present invention.
Figure 5 is an illustration of the maxillary cortical bone split including alveolar bone according to an embodiment of the present invention.
Figure 6 is an illustration of the maxillary sinus segmentation results according to an embodiment of the present invention.
Figure 7 is an exemplary view showing the inferior alveolar neural tube division results in accordance with an embodiment of the present invention.
8 is a conceptual diagram of occlusal plane extraction according to an embodiment of the present invention.
Figure 9 is an illustration of the occlusal plane extraction results according to an embodiment of the present invention.
10 is a conceptual diagram of the arch arch extraction according to an embodiment of the present invention.
Figure 11 is a conceptual diagram of the arch form curved according to an embodiment of the present invention.
Figure 12 is an illustration of the arch extraction results in accordance with an embodiment of the present invention.
Figure 13 is a conceptual diagram of the placement position selection in accordance with an embodiment of the present invention.
14 is a conceptual diagram of calculating the center point and the direction vector of both peripheral teeth in accordance with an embodiment of the present invention.
15 is a conceptual diagram for calculating a minimum distance and a center point between both peripheral teeth of an absent tooth according to an exemplary embodiment of the present invention.
Figure 16 is a conceptual diagram of the calculation of the center point of the dental arch according to an embodiment of the present invention.
17 is a conceptual view of the final placement position selection in accordance with an embodiment of the present invention.
18 is a conceptual diagram of selecting an implantation angle using the peripheral tooth angle according to an embodiment of the present invention.
19 is a view illustrating a final implant placement position and area extraction according to an embodiment of the present invention.
20 is an illustration of adjustment when the implant is close to the neural tube according to one embodiment of the present invention.
21 is a conceptual diagram of selecting an implantation region when there is a continuous member tooth according to an embodiment of the present invention.
22 is a conceptual diagram of selecting an implantation region when there is one member tooth according to an embodiment of the present invention.
23 is an operation control flowchart for automatically selecting an implant placement region according to an embodiment of the present invention.
Figure 24 is an illustration of a tooth diagram step by step automatic selection of implant implantation area according to an embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings will be described in detail the operating principle of the present invention. In the following description of the present invention, when it is determined that a detailed description of a known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted. Terms to be described later are terms defined in consideration of functions in the present invention, and may be changed according to intentions or customs of users or operators. Therefore, the definition should be made based on the contents throughout the specification.

Figure 1 shows a detailed block configuration of the implant placement area selection apparatus according to an embodiment of the present invention.

Hereinafter, with reference to Figure 1 will be described in detail the operation of each component of the implant placement area selection apparatus 100 according to an embodiment of the present invention.

First, the tooth region dividing unit 130 divides each region constituting the tooth based on the CT image of the tooth photographed. In this case, the CT image may be, for example, a CBCT / MDCT image.

That is, the tooth region dividing unit 130 may divide the maxillary and mandibular fissures, the alveolar bone, the maxillary sinus, the mandibular cortex, and the lower extremity neural tube based on the CT image.

2 shows individual tooth sets with Morphological Watershed segmentation. As shown in FIG. 2, individual teeth can be segmented through segmenting the maxillary and mandibular teeth from a CT image.

In addition, the tooth region divider 130 may perform individual tooth semi-automatic numbering on the teeth divided into individual teeth as described above.

That is, the individual number of teeth is completed and the tooth numbering of the predefined method for the individual teeth is performed for the algorithm for extracting the implant placement area, which is the next step, the tooth numbering is set as shown in FIG. First, the user directly places seed points on the four coronal front incisors in the maxillary and mandibular teeth, and in the direction of the arrow around each seed point 1-1, 1-2, 1-3,... It is defined as, 1-N, and numbers 2, 3, and 4 are also defined according to the direction of the arrow.

The numbering method is a method of arranging teeth having a minimum distance in order of positions by measuring only a distance in the x direction between a center point and seed points of individual teeth randomly divided around seed points designated by a user.

At this time, the seed points 1, 4 search only individual teeth at positions smaller than the x value of each seed point, and the second and third search only individual teeth at positions larger than the x value of each seed point. However, when the position of an individual tooth is smaller than the position of a previously found tooth or when it is smaller, it is considered to be closest to the center point of the tooth currently being searched for in case of being larger or smaller. In practice, the upper and lower jaw can be separated and processed separately, but is not limited thereto.

In addition, the tooth region dividing unit 130 extracts and divides the lower cortical bone located at the lower end of the individual tooth from the CT image of the tooth. Like the alveolar bone, the lower cortical bone can be easily divided if the tooth rows are normally divided.

Hereinafter, the operation of dividing the lower cortical bone in the tooth region division unit 130 will be described in more detail.

The tooth region dividing unit 130 performs region-based statistical growth on the image that is set to a threshold value of 700 to 1000 on the redesigned CT image, and then applies a fill hole algorithm to the mandible. Cortical bones with teeth come out. The mandibular cortical bone can be segmented by removing the previously segmented mandibular tooth region.

4 illustrates an image of a segmented mandible cortex including an alveolar bone, and FIG. 5 illustrates an image of a segmented maxillary cortex including an alveolar bone.

In addition, the tooth region divider 130 divides the alveolar bone from the lower cortical bone. Alveolar bone segmentation is bone tissue around the root of the tooth that is missing from the mandibular cortex, and has a socket shape. It can be implemented immediately through the intersection method between the pre-implemented mandible cortical bone and individual tooth regions. This area is replaced by a cortical bone filled inside.

In addition, the tooth region dividing unit 130 divides the maxillary sinus from the CT image of the teeth. The maxillary sinus is a segmentation necessary to know whether the maxillary sinus region is invaded when the implant is inserted in the implant placement region.

6 shows the maxillary sinus splitting results. As shown in FIG. 6, it can be seen that the maxillary sinus 1800 located above the individual teeth is segmented from the CT image through the tooth region dividing unit 130 to display an accurate position.

In addition, the tooth region dividing unit 130 divides the lower alveolar neural tube that is formed under the lower jaw teeth.

At this time, in the Hachijo neural tube segmentation, as shown in Figure 7, the user selects several points of the neural tube, including both ends of the neural tube, generates a guideline using Cubic-Hermite spline interpolation, using the lower Split neural tube 3520.

Next, the tooth feature extraction unit 150 is based on the CT image photographing the teeth and the information based on the individual teeth, alveolar bone, maxillary sinus, maxillary and mandibular cortical bone, lower alveolar neural tube and the like divided by the tooth region divider 130 The characteristic structures of occlusal plane, dental arch, etc. are extracted.

First, the tooth feature extraction unit 150 extracts a plane in which the maxillary and mandibular teeth engage. 8 illustrates an operation concept of extracting the occlusal plane from the tooth feature extraction unit 150.

Referring to FIG. 8, the tooth feature extractor 150 converts the maxillary and mandibular teeth into 3D points as shown in FIG. 8A. As shown in FIG. 8B, an initial fitting plane pln1 is extracted using sample points of maxillary or mandibular teeth. Subsequently, as shown in (c) of FIG. 8, points farthest from the initial occlusal plane pln1 at teeth 1 and 6 are respectively selected and selected as the point set. In this case, the tooth feature extraction unit 150 selects at least three points when selecting the above points. For example, you can select at least one point from both teeth # 1 and # 2 if both teeth are missing. Also, 6 pairs of teeth (right / left), 5, 7 and 4 in the absence of a tooth, and a pair may consist of other teeth (for example, 6 left and 7 right) .

Subsequently, the tooth feature extraction unit 150 obtains a fitting plane (pln2) passing through the point set obtained as described above as shown in FIG. 8 (d) and selects the occlusal plane.

Figure 9 shows the occlusal plane extraction results, it can be seen that the occlusal plane for the dentition is calculated correctly.

In addition, the tooth feature extracting unit 150 calculates an arch form indicating an arrangement state of the maxillary and lower teeth based on the information about the tooth region divided from the tooth region dividing unit 130. At this time, the arch form represents a form in which the teeth are arranged, the tooth feature extraction unit 150 extracts the center of each tooth of the maxillary or lower teeth, and generates a curved line connecting each center To extract the arch form showing the arrangement of the teeth.

As shown in FIG. 10, the tooth feature extraction unit 150 moves to the occlusal plane 2100 to obtain intersection points 2300 where the moved occlusal plane 2200 passes through the maxillary and mandibular teeth. At this time, in moving the occlusal plane 2100, for example, the maxillary dentition may be moved 5mm above the maxillary dentition, and the mandibular dentition may be moved below 3mm of the mandibular dentition, but is not limited thereto.

In addition, the tooth feature extracting unit 150 may generate a virtual tooth by mirroring the tooth in which the member is generated in order to generate an arch form when there is a dental tooth member. At this time, the mirroring as described above may be performed when there is one member tooth out of two teeth seven. That is, when the tooth 7 is absent, since one end of the arch form is cut, mirroring may be performed to generate a complete arch form.

Subsequently, the tooth feature extractor 150 applies a curve approximation to the intersection point as shown in FIG. 11 to generate a curve passing through the intersection point. In this case, the tooth feature extraction unit 150 may apply a parameterization in which a linear portion and a linear portion corresponding to the reference numeral 2400 are mixed in performing the above approximation. In addition, the curve may be approximated by cubic B-Spline, but is not limited thereto.

Figure 12 shows the results of the arch arch extraction. FIG. 12A illustrates the arch form calculated from the maxillary and mandibular teeth in the absence of an absent tooth, and it can be seen that the arch form is formed to pass through the center of the teeth. 12 (b) shows that the dental arch is formed accurately by applying a cubic B-spline curve approximation in the case of the absence tooth.

Next, the implant placement region selector 170 detects the position of the lost tooth by referring to the structural information about the tooth region and the feature information extracted from the tooth feature extractor 150 from the tooth region divider 130. The implant placement zone is selected at the position of the missing tooth.

The implant placement region selector 170 extracts a position where a tooth is lost in the maxillary or mandibular dentition.

At this time, in extracting the position of the lost tooth, the implant placement area selection unit 170 finds the absent tooth (s) by the tooth number, and finds the neighboring tooth (s) of each of the absent teeth or the continuous absent teeth. Subsequently, as shown in FIG. 13, the implant placement region selecting unit 170 obtains an intersection point by moving the occlusal plane located in the arch form up to 3 mm in the upper jaw downward, and then curves the same way as the extraction of the arch form. Create an arch form 2 by creating. This arch form 2 is used to find the implantation position and the implantation angle of the implant tooth in the future.

Subsequently, as shown in FIG. 14, the implant placement region selector 170 obtains an intersection point of two neighboring teeth (both teeth of an absent tooth) using an occlusal plane located in the dental arch, and a center point of the intersection point of each tooth. After finding (center point), we find a vector (vector: dirVec = c1 c2) connecting two center points (c1, c2). Such a vector dirVec is preferably directed to the left at all times from the patient center, but is not limited thereto.

Subsequently, as shown in FIG. 15, the implant placement region selecting unit 170 finds the minimum distance between the two teeth and two points ec1 and ec2 constituting the same by using dirVec. In this case, e1 and e2 may be intersection points forming a minimum distance.

Also, as shown in FIG. 16, the implant placement region selector 170 finds a point ac on the arch form (closest to) the center point m of two points, and at this point ac. Find the point (ac2) above the nearest arch form 2.

Subsequently, the implant placement region selector 170 obtains a vector iv connecting ac and ac2. At this time, project the ac2 to a plane with ac to dirVec so that iv can only be steered from the occlusal normal vector to the inside or outside of the tooth, then recalculate ac2 and recalculate iv again. Calculate

Subsequently, as shown in FIG. 17, the implant implantation region selector 170 searches for the alveolar bone region within a predetermined distance from the vector, and uses the highest (based on the occlusal plane (base) or an implantation angle) within the alveolar bone in this region. (Optional)) Set the point where the face and the vector pass through as the insertion position.

Hereinafter, an operation of generating an implant placement model in the implant placement region selection unit 170 will be described in detail.

The implant placement region selector 170 calculates an implantation angle of a tooth to be implanted, as shown in FIG. 18. At this time, the implantation angle may use the vector (iv) obtained in the implantation position selection process in FIG. 17. At this time, since iv is sensitive as determined according to ac and ac2, the implantation angle is determined by applying the average value of the angle of the surrounding tooth as an option. In this case, the angle of insertion is adjusted to adjust only the inside / outside angle.

Subsequently, as shown in FIG. 19, the implant implantation region selector 170 forms a cylindrical shape of the implant tooth to be implanted using the implantation angle obtained above and the minimum distance (cylinder diameter) of both of the surrounding teeth. Create

That is, the implant tooth consists of, for example, two cylinders up and down, and the upper first cylinder 3500 centers the placement position from the placement position to the average height of both teeth in the length of the first cylinder 3500. The lower second cylinder 3510 uses the thickness of the radius (2.5 mm, smaller than the first cylinder radius) and the average length from the placement position to the peripheral both teeth roots as the length of the second cylinder 3510. . In this case, since the length of the second cylinder 3510 may be smaller than the length of the first cylinder 3500, the root portion may be missing, not divided, or frayed. It can be specified as 1.5 times the length.

Subsequently, as shown in FIG. 20, the implant placement region selecting unit 170 checks whether the second cylinder approaches the lower extremity neural tube 3520 or less (calculates the distance between the neural tube and the cylinder). Only adjust briefly (angle is manually adjusted).

Also, as shown in FIG. 21, when the implant placement region selection unit 170 has one or more consecutive absent teeth, the number of absent teeth is found through the peripheral number of teeth on both sides of the continuous absent tooth, and the minimum of both peripheral teeth. Divide the distance by the number to create the number of implant regions (same length). Subsequently, the center point of each region is found, the nearest point is found in the spline curve of the arch form, and each implantation position is found using the implantation position selection algorithm described above.

Also, as shown in FIG. 22, the implant placement region selecting unit 170 temporarily includes mirroring when there is only one peripheral tooth (no tooth 7), that is, when the tooth 7 is absent. Find the intersection point. Subsequently, the implant insertion position and the implantation region are obtained by applying the temporary intersection point of the seventh member tooth thus generated to the implantation position and the implantation region selection algorithm.

FIG. 23 is a flowchart illustrating an operation control flow for selecting an implantation region in an implant placement region selection apparatus according to an embodiment of the present invention. 24 is an exemplary view of a tooth diagram for each stage of implant selection region automatic selection according to an embodiment of the present invention.

Hereinafter, an embodiment of the present invention will be described in more detail with reference to FIGS. 1 to 24.

The implant placement region selection apparatus 100 divides the teeth from the CT image 1000 photographing the teeth (S10).

Subsequently, when the dental dentition is separated as described above, the implant placement region selection device 100 divides the alveolar bone and the maxillary sinus from the CT image, and divides the lower cortical bone and the lower alveolar neural tube, and the area of the main tooth components in the CT image. Division is performed (S12).

Subsequently, the implant placement region selection apparatus 100 calculates an occlusal plane between the maxillary and mandibular teeth (S14). At this time, in calculating the occlusal plane, the implant placement region selection apparatus 100 selects the initial occlusal plane using the sample points of the maxillary and mandibular teeth, and a plurality of teeth spaced relatively far from the initial occlusal plane After selecting, and calculate the final occlusal plane connecting the points by the end of the plurality of teeth as a point. In this case, the plurality of teeth is preferably set to at least three, but is not limited thereto.

Subsequently, the implant placement region selection apparatus 100 calculates the arch form (S16). At this time, in calculating the dental arch, the implant placement area selection device 100 is spaced apart by a certain distance from the upper or lower teeth of the maxillary dental floss, the intersection point where the moved occlusal plane intersects the maxillary or lower dental dentition Find the point of intersection. Then, curve approximation creates a curve through the intersection point to create an arch. Such a curve may be, for example, an approximation of a cubic B-Spline curve, but is not limited thereto.

In the case of extracting the tooth features related to implant placement such as occlusal plane, dental arch, etc., the implant placement region selection device 100 extracts the tooth position lost in the maxillary or mandibular dentition.

Subsequently, the implant placement region selection device 100 selects an implantation region, that is, an implantation position and an implantation angle, of the implant to be implanted at the lost tooth position by moving the arch form to the upper portion of the maxillary dentition or to the lower portion of the mandibular dentition. (S18).

At this time, in calculating the placement position, the implant placement area selection device 100 obtains the intersection point of the adjacent teeth located on both sides of the missing tooth using the occlusal plane located in the first dental arch, and then The center point is extracted to obtain a first vector dirVec connecting two center points.

Subsequently, the implant placement region selection apparatus 100 finds two points that form the minimum distance and the minimum distance between the two teeth using the first vector, and finds the first point on the dental arch closest to the center point of the two points. The second point closest to the first point is found among the points of the second arch form in which the first arch form is moved a predetermined distance to the upper portion or the lower portion of the dental arch.

Subsequently, the implant placement area selection apparatus 100 obtains a second vector connecting the first point and the second point, finds the alveolar bone area in a certain transaction from the second vector, and locates the intersection where the highest surface and the vector pass in the alveolar bone. Select by location.

Next, in calculating the implantation angle of the implant to be implanted at the selected implantation position as described above, the implant implantation region selection device 100 may calculate the angle of the second vector as the implantation angle of the implant tooth, or peripheral teeth The average value of the angle of may be calculated as the implantation angle.

Subsequently, the implant placement region selection apparatus 100 generates an implantation shape of the implant tooth to be implanted using the implantation position, the implantation angle, and the minimum distance of both teeth generated as described above (S20). This implantation shape may be generated in a cylindrical shape, but is not limited thereto.

At this time, the cylinder for implantation of the implant may be composed of a cylinder having two different diameters, the first cylinder (3500) toward the center of the placement position is the diameter corresponding to the minimum distance in the case of one missing tooth It may be generated to have, and when two or more missing teeth can be generated to have a diameter corresponding to the distance divided by the minimum distance divided by the number of teeth. In addition, the average height of both teeth from the placement position may be generated with the length of the first cylinder 3500. In addition, the diameter of the cortical bone second cylinder 3510 is generated to be smaller than the size of the radius of the first cylinder 3500, the average length from the placement position to the peripheral both teeth roots to the length of the second cylinder 3510 Can be generated.

At this time, since the length of the second cylinder 3510 is smaller than the length of the first cylinder 3500, there may be no root portion of the surrounding teeth, or may not be divided, or the teeth are worn out. It may be generated to a size 1.5 times the length, but is not limited thereto.

In addition, the implant placement area selection apparatus 100 checks whether the length of the second cylinder 3510 approaches within the predetermined distance from the lower alveolar neural tube in setting the length of the second cylinder 3510, The length of the two cylinders 3510 can be shortened again.

As described above, according to an embodiment of the present invention, the tooth region including the tooth, the maxillary sinus, the alveolar bone / cortical bone, and the lower alveolar neural tube is divided from the CT image of the tooth, and the location of the lost tooth using the arch After the selection, the implantation position, the implantation angle, and the depth of the implant tooth are automatically and accurately calculated so as not to damage the inferior alveolar neural tube, so that the implant procedure can be performed more accurately and efficiently.

Combinations of the steps of each flowchart attached to the present invention may be performed by computer program instructions. These computer program instructions may be mounted on a processor of a general purpose computer, special purpose computer, or other programmable data processing equipment such that the instructions performed through the processor of the computer or other programmable data processing equipment are described in each step of the flowchart. It will create a means to perform them. These computer program instructions may be stored in a computer usable or computer readable memory that can be directed to a computer or other programmable data processing equipment to implement functionality in a particular manner, and thus the computer usable or computer readable memory. It is also possible for the instructions stored therein to produce an article of manufacture containing instruction means for performing the functions described in each step of the flowchart. Computer program instructions may also be mounted on a computer or other programmable data processing equipment, such that a series of operating steps may be performed on the computer or other programmable data processing equipment to create a computer-implemented process to create a computer or other programmable data. Instructions for performing the processing equipment may also provide steps for executing the functions described in each step of the flowchart.

In addition, each step may represent a module, segment or portion of code that includes one or more executable instructions for executing a specified logical function (s). It should also be noted that in some alternative embodiments, the functions noted in the steps may occur out of order. For example, the two steps shown in succession may in fact be performed substantially simultaneously or the steps may sometimes be performed in the reverse order, depending on the function in question.

Meanwhile, in the above description of the present invention, specific embodiments have been described, but various modifications may be made without departing from the scope of the present invention. Therefore, the scope of the invention should be determined by the claims rather than by the described embodiments.

100: implant placement area selection device 130: tooth area division
150: tooth feature extraction unit 170: implant placement area selection unit

Claims (23)

A tooth region divider which receives a CT image of a tooth and divides the tooth region from the CT image;
A tooth feature extraction unit for calculating the occlusal plane of the maxillary and mandibular teeth, the dental arch of the maxillary teeth and the mandibular teeth based on the information on the tooth region;
An implant implantation region selector for detecting the position of the tooth region and the maxillary or mandibular orthodontic tooth and selecting an implantation region of the implant tooth to be implanted at the position of the missing tooth,
The implant placement region selection unit,
Calculating a first dental arch located in the occlusal plane and a second dental arch positioned at a predetermined distance from the occlusal plane toward the tooth, and using two first dental arches, two adjacent teeth positioned on both sides of the lost tooth; Obtaining an intersection point of the first arch form, finding two points that form a minimum distance between the two adjacent teeth, and extracting the first arch form first point closest to the center point between the two points;
Finding the second point of the second arch arch closest to the first point and calculating a vector connecting the first point and the second point, and then the vector intersects the alveolar bone of the maxillary or mandibular dentition. To select the implantation position of the implant tooth
Implant placement area selection device.
The method of claim 1,
The tooth feature extraction unit,
A sample point of the maxillary or mandibular teeth is set and the sample points are connected to select an initial occlusal plane that crosses the maxillary or mandibular teeth, and the teeth are spaced farthest from the initial occlusal plane. After selecting a plurality of teeth, connecting the ends of the plurality of teeth to calculate the occlusal plane
Implant placement area selection device.
The method of claim 1,
The tooth feature extraction unit,
After the occlusal plane is spaced apart by a predetermined distance from the upper portion of the maxillary teeth or the lower portion of the mandibular teeth, an intersection point where the moved occlusal plane intersects the maxillary teeth or the mandibular teeth is obtained, and a curve approximation is made. to generate the arch form by generating a curve passing through the intersection point
Implant placement area selection device.
delete The method of claim 1,
The implant placement region selection unit,
Selecting an angle between the vector and the occlusal plane as an implantation angle of the implant tooth
Implant placement area selection device.
The method of claim 1,
The implant placement region selection unit,
Calculating an average value of angles of the plurality of predetermined teeth around the lost tooth and the occlusal plane, and selecting the average value as an implantation angle of the implant tooth;
Implant placement area selection device.
The method of claim 5,
The implant placement region selection unit,
The implantation shape of the implant tooth is generated by using the implantation position, the implantation angle, and the minimum distance between both teeth of the lost tooth.
Implant placement area selection device.
The method of claim 7, wherein
The implant placement region selection unit,
The shape of the implant tooth is generated in the form of two cylinders connected,
A first cylinder of the two cylinders is generated at the insertion position, and when the missing tooth is one, the diameter of the first cylinder is formed to a length corresponding to the minimum distance between two teeth adjacent to the missing tooth,
Generating a second cylinder to be connected to the first cylinder in the cortical bone region of the implantation position, wherein the diameter of the second cylinder is smaller than the diameter of the first cylinder;
Implant placement area selection device.
The method of claim 7, wherein
The implant placement region selection unit,
The shape of the implant tooth is generated in the form of two cylinders connected,
A first cylinder of the two cylinders is generated at the insertion position, and when the missing teeth are two or more, the distance divided by the number of the missing teeth divided by the minimum distance between the two teeth adjacent to the missing teeth is determined by the number of the first cylinders. Formed into diameter,
Generating a second cylinder to be connected to the first cylinder in the cortical bone region of the implantation position, wherein the diameter of the second cylinder is smaller than the diameter of the first cylinder;
Implant placement area selection device.
The method according to claim 8 or 9,
The implant placement region selection unit,
The length of the first cylinder to form an average length of a plurality of predetermined teeth around the missing tooth
Implant placement area selection device.
The method according to claim 8 or 9,
The implant placement region selection unit,
The length of the second cylinder is formed as an average value of the tooth root lengths of the plurality of preset teeth around the lost tooth.
Implant placement area selection device.
In the implant implantation region selection method performed by the implant implantation region selection device,
Receiving a CT image of a tooth and dividing a tooth region from the CT image;
Calculating the occlusal plane of the maxillary and mandibular teeth and the arch form of the maxillary and the mandibular teeth based on the information on the tooth region;
Detecting the location of the maxillary or mandibular missing teeth;
Selecting an implantation region of the implant tooth to be implanted at the position of the lost tooth
Including;
Selecting the implantation region,
Calculating a first dental arch located in the occlusal plane and a second dental arch positioned at a predetermined distance in the tooth direction direction from the occlusal plane;
Obtaining an intersection point between two adjacent teeth located on both sides of the lost tooth and the first arch form using the first arch form,
Extracting the first dental arch first point closest to the center point between the two points by finding two points forming the minimum distance between the two adjacent teeth;
Calculating a vector connecting the first point and the second point by finding the second point of the second arch form closest to the first point;
And selecting an intersection where the vector intersects the alveolar bone of the maxillary or mandibular teeth as an implantation position.
The method of claim 12,
The step of calculating the occlusal plane,
Setting a sample point of the maxillary or mandibular dentition,
Connecting the sample points to select an initial occlusal plane across the maxillary or mandibular teeth,
Calculating the occlusal plane by selecting a plurality of teeth and connecting the ends of the plurality of teeth in order of teeth spaced farthest from the initial occlusal plane;
How to select the implant placement area.
The method of claim 12,
The step of calculating the arch form,
Moving the occlusal plane a predetermined distance to an upper portion of the maxillary dentition or a lower portion of the lower dentition;
Obtaining an intersection point at which the moved occlusal plane intersects the maxillary or mandibular teeth,
Generating the arch form by generating a curve passing through the intersection point through curve approximation.
How to select the implant placement area.
delete The method of claim 12,
Selecting the implantation region,
Selecting an angle between the vector and the occlusal plane as an implantation angle of the implant tooth;
How to select the implant placement area.
The method of claim 16,
The step of selecting the insertion angle,
Calculating an average value of angles of the plurality of predetermined teeth around the lost tooth and the occlusal plane;
And selecting the average value as an implantation angle of the implant tooth.
How to select the implant placement area.
The method of claim 16,
Generating an implantation shape of the implant tooth by using the implantation position, the implantation angle, and the minimum distance between both teeth of the lost tooth;
How to select the implant placement area.
The method of claim 18,
Generating the shape of the implant,
Generating a first cylinder having a diameter of a minimum distance between two teeth adjacent to the lost tooth in the implantation position when the loss tooth is one, and is connected to the first cylinder in the cortical bone region of the implantation position, Generating a second cylinder having a diameter smaller than the first cylinder;
How to select the implant placement area.
The method of claim 18,
Generating the shape of the implant,
Creating a first cylinder at the placement position having a diameter of a distance obtained by dividing the minimum distance between two adjacent teeth and the lost tooth by the number of lost teeth when the missing teeth are two or more;
Generating a second cylinder connected to the first cylinder in the cortical bone region of the implantation position, the second cylinder having a smaller diameter than the first cylinder;
How to select the implant placement area. The method of claim 19 or 20,
The length of the first cylinder,
The average length of a plurality of predetermined teeth around the missing tooth is formed
How to select the implant placement area.
The method of claim 19 or 20,
The length of the second cylinder,
It is formed as an average value of the tooth root length of the plurality of predetermined teeth around the lost tooth
How to select the implant placement area.
A computer-readable recording medium having a computer program stored therein for causing a processor to perform the method of any one of claims 12-14 and 16-20.

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