JP2013066600A - Tap for forming female screw of tooth root - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tap for forming a female screw of a tooth root, capable of suppressing the damage or destruction of the tooth root and stably vertically implanting and fixing a post when a male screw post for abutment construction is implanted vertically to a root canal of the tooth root of a tooth during the abutment construction in the construction of crown prosthesis structure.SOLUTION: For the tap 1 for forming the female screw of the tooth root, when implanting and fixing the male screw post for the abutment construction to the root canal of the tooth root of the tooth when constructing an abutment structure or the crown prosthesis structure, since the female screw is formed in the root canal of the tooth root beforehand, the post itself is not screwed by pressing or cutting surrounding dentin or the like by a screw thread while making it directly cut into the root canal of the tooth root. Therefore, it is possible to provide the tap 1 that can form the female screw capable of suppressing weakening of the tooth root and the damage or destruction of the tooth root by that and stably implanting and fixing the male screw post for the abutment construction.

Description

  The present invention relates to a tap for forming an internal thread of a tooth root, an abutment structure, and an abutment construction method. More specifically, when a male threaded post for abutment construction is planted in the root canal of a tooth root, a tap or support for forming a female thread of a tooth root that can prevent damage or destruction of the root and stably fix the post. The present invention relates to a built-in structure and a support structure.

  If most of the crown is lost due to caries, etc., a dental prosthetic structure that mimics the shape of a tooth called an artificial crown (crown) is prepared outside the oral cavity on the remaining tooth or root. It is necessary to perform a dental prosthesis using a dental adhesive on the abutment. In this case, when a portion corresponding to the abutment is missing, a measure for attaching the prosthetic structure is performed after reinforcing the tooth structure, that is, abutment construction.

  As a prosthetic structure after the abutment has been constructed, a structure in which the cast crown is fixed to the abutment with an adhesive is known. For example, the root canal of the root of an appropriately treated tooth is known. After filling the bottom part with a treatment resin material as a root filler, a molded abutment made of a resin for the core (abutment) having adhesiveness is formed on the abutment building post planted in the root canal of the tooth root Then, after the abutment construction is made and the abutment construction is formed, a method is adopted in which the coated crown cast on the abutment is bonded with an adhesive such as cement. The abutment-building post planted in the root canal of the tooth root is made of metal, ceramic, fiber, composite resin, or a composite material of these, and is generally fixed in the root canal with resin cement or cement cement. Will be. In addition, as the male thread post for abutment construction, a screw thread is formed in a direction perpendicular to the insertion direction of the dental abutment to prevent the covering crown structure from falling off after the dental abutment is set. Are also provided (see, for example, Patent Document 1). The male thread post for abutment construction in which such a thread is formed is planted and fixed to the root canal by directly biting into the root canal of the tooth root and compressing or cutting the surrounding dentin with the thread.

JP-T 6-500263 Publication

  However, in the case where the male thread post for abutment construction in which the thread is formed is directly bitten into the root canal of the tooth and the surrounding dentin is compressed or cut with the thread, the root of the root Brittleness was likely to occur, leading to damage or destruction of the root, and the abutment and crown prosthesis structure were likely to collapse. In addition, when the screwing is insufficient, the post may not be sufficiently fixed.

  The present invention has been made in view of the above-described problems, and in the construction of an abutment in the construction of a crown prosthesis structure, the root screw is damaged when the abutment-building male screw post is planted in the root canal of the tooth root. Another object of the present invention is to provide an internal thread forming tap, an abutment structure, and an abutment construction method for a root that can suppress destruction and can stably fix a post.

  In order to solve the above-mentioned problems, the internal thread forming tap for a tooth root according to the present invention is provided with a thread portion made of an external thread on the outer periphery and provided in a direction parallel to the axial direction so as to divide the thread portion. It is a tap in which a cutting edge is formed along the groove, and is used to form a female thread for planting a male thread post for abutment construction with a male thread formed on the outer periphery of the root canal of the root. It is characterized by.

  The internal thread forming tap for a tooth root according to the present invention is characterized in that, in the above-described present invention, the outer diameter of the threaded portion is φ0.7 to 2.5 mm.

  The abutment structure according to the present invention includes a structure in which an abutment-building male screw post having a male screw formed on the outer periphery is screwed into a root canal of a tooth root in which a female screw is formed and is planted. .

  In the abutment structure according to the present invention, in the above-described present invention, a length L of a portion where the root canal of the tooth root and the external thread post for abutment construction are screwed is 2.0 to 5.0 mm. It is characterized by.

  In the abutment construction method according to the present invention, an internal thread is formed on the root canal of the root with the internal thread forming tap for the root of the present invention, and an external thread is formed on the outer periphery of the root canal on which the internal thread is formed. It includes screwing and setting a male thread post for abutment construction.

  The tap for forming an internal thread of a tooth root according to the present invention, when constructing an abutment structure or a crown prosthesis structure, in order to plant and fix the external thread post for an abutment structure in the root canal of the tooth root, Since the internal thread is formed in the tube, the post itself bites directly into the root canal of the root, and the surrounding dentin is not pressed or cut with a screw thread, so the root is weakened and the root is damaged. In addition, it is possible to provide a tap capable of forming a female screw that can suppress breakage and can stably fix the male screw post for abutment construction.

  The abutment construction according to the present invention employs a structure in which a male screw post for abutment construction having a male screw formed on the outer periphery is screwed into a root canal of a tooth having a female screw formed in advance and is planted. Therefore, it is possible to provide a stable abutment structure (an abutment built on the root) in which the post is sufficiently planted and fixed, suppressing weakening of the root and damage or destruction of the root due to the post planting. be able to.

  In the abutment construction method according to the present invention, a female thread is formed on the root canal of a tooth root using the above-described tap for forming a female thread of a root according to the present invention, and then a male thread is formed on the outer periphery of the root canal on which the female thread is formed. Since the abutment-building male screw post is screwed and planted, the post itself can be directly bitten into the root canal, and the surrounding dentin can be squeezed or cut with a screw thread without being screwed in. It is possible to provide a means for building a stable abutment construction in which the root is weakened and the root is damaged or destroyed by the above-mentioned, and the post is sufficiently planted and fixed.

It is the side view which showed the one aspect | mode of the tap for internal thread formation of the tooth root which concerns on this invention. It is II-II sectional drawing of FIG. It is explanatory drawing which expanded the front-end | tip part of the tap. It is the schematic which showed the state which formed the internal thread in the root canal of the root using the tap which concerns on this invention. It is the schematic which showed the state which planted the male screw post for abutment construction in the root canal in which the thread was formed. It is the schematic which showed the part (screwing part) by which a root canal and the external thread post for abutment construction are screwed together. It is the schematic which showed the part (screwing part) by which a root canal and the external thread post for abutment construction are screwed together. In FIG. 5, it is the schematic which showed the state which attached the cylindrical member to the screw head of the external thread post for abutment construction. It is the schematic which showed the one aspect | mode of the abutment structure with which the covering crown was mounted | worn. It is the schematic which showed the other aspect of the abutment structure with which the covering crown was mounted | worn.

  The configuration of the present invention will be described below with reference to the drawings.

(I) Configuration of tap 1:
FIG. 1 is a side view showing an embodiment of a female root-forming tap 1 (hereinafter simply referred to as “tap 1”) according to the present invention. FIG. 2 is a sectional view taken along line II-II in FIG. FIG. 3 is a cross-sectional view, and FIG.

  A tap 1 according to the present invention is for cutting, for example, a right-handed female screw into a root canal of a tooth root. A screw portion 2 having a male screw corresponding to the female screw to be processed is provided on the outer periphery, and the screw portion. 2 is integrally provided in a direction parallel to the axis X. The threaded portion 2 has a complete threaded portion 21 having a constant thread height, and the diameter decreases from the complete threaded portion 21 toward the tip side of the threaded portion 2 (in the direction of the arrow in FIGS. 1 and 3; the same applies hereinafter). The groove portion 4 is provided in a direction parallel to the axis X so as to divide the screw portion 2. The groove portions 4 are symmetrically arranged at substantially equal intervals around the axis X (in the present embodiment, three are shown), and cutting edges 41 are formed along the groove portions 4. . The tap 1 can be made of a known metal material such as high-speed tool steel or cemented carbide.

  In the present embodiment, the shank 3 is formed in a substantially conical shape having an axis X. Note that the tap 1 of the present embodiment is provided with a grip portion 5 having a substantially regular hexagonal cross section with respect to the axial center at the end of the shank 3 so that the tap 1 can be easily gripped and operated.

  The screw part 2 constituting the tap 1 is a part for cutting the internal thread on the root canal of the tooth root while rotating by the rotational force transmitted from the grip part 5 through the shank 3, and is shown in FIG. Thus, the biting part 22 and the complete mountain part 21 connected to the biting part 22 are provided. Further, three groove portions 4 are respectively provided in the outer peripheral surface of the screw portion 2 so as to be substantially parallel to the axis X.

  The biting portion 22 constituting the screw portion 2 is a portion for forming a female screw (see FIG. 4 to be described later) by cutting the root canal of the root to be processed. As shown in FIG. 4, the taper is formed in a tapered shape having a predetermined angle α ° (for example, α = 2 to 30 °) with the outer diameter becoming smaller as it goes toward the tip end side of the screw portion 2. Further, the complete mountain portion 21 is a portion for finishing the female screw formed by the biting portion 22, and is formed in substantially the same shape as the shape of the female screw to be formed in the root canal of the root to be processed. Yes.

  The groove part 4 is a part for accommodating chips generated in the biting part 22 at the time of cutting, and as shown in FIG. 1, in this embodiment, a substantially straight line parallel to the axis X. It is formed in a shape and extends from the tip surface of the screw portion 2 to a position that reaches the shank 3 beyond the complete mountain portion 21. For example, the groove portion 4 is translated in the axial direction from the tip end side of the screw portion 2 toward the rear end side (direction opposite to the arrow direction in FIG. 1) while rotating a disk-shaped grindstone. Can be formed. In addition, the groove part 4 may have a twisted shape in addition to a substantially straight line shape as shown in the present embodiment.

  The pitch of the tap 1 can be appropriately determined according to the pitch of the male screw formed on the outer periphery of the male screw post for abutment construction (see FIG. 5 described later) to be planted in the root canal of the tooth root. The pitch is preferably selected within the range of 0.2 to 0.5 mm, particularly preferably 0.25 to 0.4 mm. Further, the outer diameter of the tap 1 (the outer diameter of the complete mountain portion 21) can be determined in accordance with the outer diameter of the male screw of the abutment-building male screw post, but the female screw is formed in the root canal of the tooth root. In consideration of this, the outer diameter of the tap 1 is preferably selected within the range of φ0.7 to 2.5 mm, more preferably selected within the range of φ0.7 to 2.2 mm, and φ1. It is particularly preferable to select within the range of 0 to 2.0 mm. In addition, since the size such as the outer diameter of the female screw formed by the tap 1 is generally larger than the size of the outer diameter or the like of the tap 1, in addition to the outer diameter of the male screw formed on the outer periphery of the male screw post for abutment construction, What is necessary is just to determine suitably considering an effective diameter, a trough diameter, etc. (The definition of an outer diameter, a pitch, etc. applies to JISB0176-1.).

  FIG. 4 is a schematic view showing a state in which an internal thread F is formed in the root canal 71 of the tooth root 7. An example of a method for forming the internal thread F in the root canal 71 of the root 7 using the tap 1 according to the present invention will be described. First, a therapeutic resin material or medicine is applied to the lowermost part (not shown) of the root canal 71 of the root 7. Etc. (not shown), etc., and after taking appropriate measures, etc., the root canal 71 is formed with a desired outer diameter by forming a pilot hole 72 in the root canal 71 with, for example, a peasor reamer (not shown), and the surface To flatten. In this case, the outer diameter of the pilot hole 72 is preferably 80 to 85% of the outer diameter of the tap 1, for example. When the pilot hole 72 is formed, the tap 1 according to the present invention is inserted into the pilot hole 72, and the screw portion 2 (male screw portion) of the tap is inserted into the pilot hole 72, and the grip portion 5 is centered on the axis X. Is rotated clockwise to form a female thread F.

(II) Abutment structure T:
FIG. 5 is a schematic view showing a state where the male thread post 6 for abutment construction is planted in the root canal 71 of the root 7 having the female thread F formed on the outer periphery (abutment structure T). The abutment-building male screw post 6 (hereinafter may be simply referred to as “post 6”) includes a screw head 61 and a shaft portion 62 formed with a male screw (screw thread; the same applies hereinafter) on the outer periphery. The pitch and outer diameter of the male screw of the post 6 are determined in correspondence with the pitch and outer diameter of the tap 1 for forming the female screw F described above. In the present invention, with the tap 1 according to the present invention, the post 6 in which the external thread F is formed in the root canal 71 in the state where the internal thread F is formed in the root canal 71 in advance. Since the tooth root 7 is weakened and the root 7 is prevented from being damaged or broken, the male thread post 6 for abutment construction can be stably planted and fixed. The shape of the tip 63 (screw tip) of the post 6 is not particularly limited and may be flat. However, as shown in FIG. 5, the diameter may decrease toward the bottom of the root canal 71. preferable.

  In order to plant the post 6 having a male screw (thread) formed on the outer periphery in the root canal 71 of the root 7, the tap 1 according to the present invention can be used for the root canal 71 having the female screw F formed by the method described above. By screwing (screwing) the post 6 using a screwdriver or the like, it can be easily planted. In addition, when the post 6 is planted in the root canal 71, a cement material having high fluidity (not shown) is interposed to facilitate screwing and improve holding force.

  The length L of the threaded portion M of the root canal 71 of the tooth root 7 and the male thread post 6 for abutment construction in the abutment structure T is as shown in FIG. 6, the length of the portion where the internal thread F of the root canal 71 of the root 7 and the post 6 are screwed in a direction parallel to the direction of the arrow 7 in FIG. 6 and FIG. 7. By adopting the relatively fine pitch described above for the tap 1 (and the male screw of the post 6), the post 6 can be stably planted and fixed if the pitch is approximately 2.0 mm or more. The length L of the threaded portion M is preferably 2.0 to 5.0 mm, more preferably 2.0 to 4.0 mm, and particularly preferably 3.0 to 4.0 mm. .

FIGS. 6 and 7 are schematic views showing a portion M (threaded portion M) where the root canal 71 and the male thread post 6 for abutment construction are screwed together. As shown in FIG. 6, the length L of the threaded portion M is such that the shape of the tip 63 (screw tip) of the abutment-building male screw post 6 becomes smaller in the direction toward the bottom of the root canal 71 of the tooth root 7. In such a case, when a male screw (thread) formed on the tip 63 is screwed with a female screw F formed on the root canal 71, such a portion is also included in the screwed portion M ( Length L ₁ in FIG. 6). On the other hand, as shown in FIG. 7, when the tip 63 of the post 6 is not screwed inside the root canal 71 because the internal thread is not formed at the portion where the tip 63 of the post 6 of the root canal 71 is located. the, the moiety M of the length L ₂ of FIG. 7 is screwed. In addition, when the length L differs in the circumferential direction of the root canal 71 of the tooth root 7, the length L shall point out the shortest length among them.

  The abutment-building male screw post 6 is screwed into the root canal 71 of the tooth root 7 using a screwdriver (not shown) or the like. In order to facilitate holding and fixing the screwdriver to the screw head 61 of the post 6, You may make it remove the cylindrical member 64, after inserting the front-end | tip (not shown) of a screwdriver in the state which attached the removable cylindrical member 64, and screwing the post | mailbox 6 into. FIG. 8 is a schematic view showing a state in which the cylindrical member 64 is attached to the screw head 61 of the post 6 in FIG. 5. The cylindrical member 64 is a known metal material according to the size of the screw head 61. What is necessary is just to comprise with an inorganic material, a synthetic resin, etc.

  FIG. 9 is a schematic view showing an embodiment of the abutment structure T (crown prosthetic structure) to which the covering crown 9 is attached. The post structure T shown in FIG. 9 has a post 6 in which a male screw (thread) is formed on the outer periphery of the root canal 71 of the root 7 in which the female screw F is formed by the above-described method using the tap 1 according to the present invention. After the abutment 8 is formed so as to cover the post 6 by being screwed in, the cast crown 9 is fixed above the abutment 8 with an adhesive 81 such as cement interposed therebetween. is there. The abutment 8 may be formed by curing cement, various dental resins, or the like, or a precast metal member may be covered from above the post.

(III) Effects of the present invention:
As described above, the internal thread forming tap 1 of the root according to the present embodiment has the abutment-building male screw post 6 on the root canal 71 of the root 7 when the abutment-structure T or the crown prosthesis structure is constructed. Since the internal thread F is formed in the root canal 71 of the root 7 in advance when the planting is fixed, the post 6 itself does not directly cut into the root canal 71 of the root 7 and is not cut and screwed. And the tap 1 which can suppress the damage or destruction of the root canal 71 by it and can form the internal thread which can plant and fix the post 6 stably.

  Further, the abutment structure T according to this embodiment shown in FIGS. 5, 8 and 9 is also a male thread for abutment construction in which a male screw is formed on the outer periphery of the root canal 71 of the root 7 in which a female thread is previously formed. Since the structure in which the post 6 is screwed and planted is adopted, weakening of the root 7 and damage or destruction of the root 7 due to the planting of the post 6 are suppressed, and the post 6 is sufficiently planted and fixed. A stable abutment structure T can be provided.

The aspect described above shows one aspect of the present invention, and the present invention is not limited to the above-described embodiment, and has the configuration of the present invention and can achieve the objects and effects. It goes without saying that modifications and improvements within the scope are included in the content of the present invention. Further, the specific structure, shape, and the like in carrying out the present invention are not problematic as other structures, shapes, and the like as long as the objects and effects of the present invention can be achieved. The present invention is not limited to the above-described embodiments, and modifications and improvements within the scope that can achieve the object of the present invention are included in the present invention.

For example, in the above-described embodiment, as shown in FIG. 9, the abutment structure T in which the external thread is formed on the outer periphery of the root canal 71 of the tooth root 7 in which the internal thread F is formed is used as the abutment structure T that is the abutment structure. A structure in which the male screw post 6 is screwed and planted, and the abutment 8 is formed so as to cover the post 6, and then the cast covering crown 9 is fixed above the abutment 8 with an adhesive 81 interposed therebetween. Was described as an example. On the other hand, as the abutment structure T according to the present invention, the abutment-building male screw post 6 having a male screw formed on the outer periphery thereof is screwed into the root canal 71 of the root 7 in which the female screw F has been formed in advance. There is no particular limitation as long as it includes a structure.
In the following description, the same reference numerals are given to the same structures and the same members as those in the above-described embodiment, and the detailed description thereof is omitted or simplified.

FIG. 10 is a schematic view showing another aspect of the abutment structure T (crown prosthetic structure) to which the covering crown 9 is attached. As shown in FIG. 10, in the state where the male screw post 6 for abutment construction having a male screw formed on the outer periphery is screwed into the root canal 71 of the root 7 having the female screw F and planted, the post 6 is covered while covering the post 6. The abutment 8 is formed so that the screw head 61 protrudes from the abutment 8, the adhesive 81 is interposed between the covering crown 9 and the abutment 8, and the screw head 61 of the post 6 protruding from the abutment 8 is provided. You may make it fix so that it may fit in the recessed part 91 formed in the inside of the coating crown 9 previously.
In addition, the specific structure, shape, and the like in the implementation of the present invention may be other structures as long as the object of the present invention can be achieved.

  The present invention can be advantageously used as a means for building an abutment and building a prosthetic crown structure in dental treatment.

1 ... Tap for forming internal thread of tooth root (tap)
2 ... Screw part 21 ... Complete crest part 22 ... Chamfer part 3 ... Shank 4 ... Groove part 41 ... Cutting blade 5 ... Grab part 6 ... Male thread post (post) for abutment construction
61 ... Screw head 62 ... Shaft 63 ... Tip 64 ... Cylindrical member 7 ... Tooth root (tooth root)
71 ... Root canal 72 ... Pilot hole 8 ... Abutment 81 ... Adhesive 9 ... Cover crown 91 ... Recess F ... Female thread formed by tapping (female thread)
M ... The part to be screwed (screwed part)
T length of ...... core build body X ...... axis alpha ...... angle _L, L _1, L ₂ ...... screwed in part (engaging part)

The present invention relates to a female screw forming tap of the root. More particularly, the core build male screw post root canal of the root of a tooth when planted, and suppress damage to the root or destruction, post stably and planted upright fixed can tap for internal thread formation of the root Related.

The present invention has been made in view of the above-described problems, and in the construction of an abutment in the construction of a crown prosthesis structure, the root screw is damaged when the abutment-building male screw post is planted in the root canal of the tooth root. or suppressing the destruction is to provide a stable and planted upright fixed can tap for internal thread formation of the root post.

In order to solve the above-mentioned problems, the internal thread forming tap for a tooth root according to the present invention is provided with a thread portion made of an external thread on the outer periphery and provided in a direction parallel to the axial direction so as to divide the thread portion. A tap in which a cutting edge is formed along the groove formed, the outer diameter of the tap is 0.7 to 2.5 mm, and the pitch of the tap is 0.2 to 0.5 mm. It is used for forming an internal thread for planting an abutment-building external thread post having an external thread formed on the outer periphery of the root canal of the tooth root.

In addition , a structure is adopted in which a male screw post for abutment construction with a male screw formed on the outer periphery is screwed into the root canal of the tooth root in which a female screw has been formed in advance and is planted. It is possible to provide a stable abutment structure (an abutment built on the tooth root) in which the post is sufficiently planted and fixed while the weakening of the tooth root and damage or destruction of the tooth root are suppressed.

Then , after forming the internal thread on the root canal of the tooth root with the internal thread forming tap of the root according to the present invention described above, the external thread post for abutment construction in which the external thread is formed on the outer periphery of the root canal on which the internal thread is formed Since the post itself bites directly into the root canal, it does not compress the surrounding dentin with a screw thread or cut it and screw it down. It is possible to provide means for suppressing damage or destruction and for constructing a stable abutment structure in which the post is sufficiently planted and fixed.

The pitch of the tap 1 can be appropriately determined according to the pitch of the male screw formed on the outer periphery of the male screw post for abutment construction (see FIG. 5 described later) to be planted in the root canal of the tooth root. The pitch is particularly preferably selected within the range of 0.2 to 0.5 mm, and more preferably 0.25 to 0.4 mm. Further, the outer diameter of the tap 1 (the outer diameter of the complete mountain portion 21) can be determined in accordance with the outer diameter of the male screw of the abutment-building male screw post, but the female screw is formed in the root canal of the tooth root. In view of this, the outer diameter of the tap 1 is preferably selected within the range of φ0.7 to 2.5 mm, more preferably selected within the range of φ0.7 to 2.2 mm, and φ1.0 to 2 It is particularly preferable to select within a range of 0.0 mm. Since the size of the outer diameter of the internal thread formed by the tapping 1 is generally greater Ri by the size of the outer diameter of the tap 1, the other outside diameter of the external thread formed on the outer periphery of the core build male screw posts , Effective diameter, valley diameter, etc. (definition of outer diameter, pitch, etc. conforms to JIS B0176-1).

Claims (5)

The tap is formed with a cutting edge along a groove portion provided in a direction parallel to the axial direction so as to divide the screw portion while being provided with a screw portion made of a male screw on the outer periphery,
A tap for forming an internal thread of a tooth root, which is used for forming an internal thread for planting an abutment-building external thread post having an external thread formed on an outer periphery of a root canal of the root.   2. The tap for forming an internal thread of a tooth root according to claim 1, wherein an outer diameter of the thread portion is 0.7 to 2.5 mm.   An abutment structure including a structure in which an abutment-building male screw post having a male screw formed on the outer periphery is screwed into a root canal of a tooth root formed with a female screw and is planted.   4. The abutment structure according to claim 3, wherein a length L of a portion to which the root canal of the tooth root and the abutment-building male screw post are screwed is 2.0 to 5.0 mm.   An internal thread is formed in the root canal of the tooth root with the internal thread forming tap of the root according to claim 1 or 2, and an external thread is formed on the outer periphery of the root canal in which the internal thread is formed. A method of constructing an abutment comprising screwing and setting a male screw post.

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