Patent Description:
An implant refers to a replacement that restores when an original tissue is lost, but refers to a series of treatments of implanting artificial teeth in the dentist.

In order to replace a lost dental root, a fixture, which is a dental root made of titanium or the like without a rejection reaction to the human body, is planted in the alveolar bone from which the tooth is removed, and then the artificial tooth is fixed to restore the function of the tooth.

In general prostheses or dentures, the surrounding teeth and bones are damaged over time, but there are advantages in that the implants do not injure the surrounding dental tissues and do not have cavities while having the same function and shape as the natural teeth and thus can be used semi-permanently.

An artificial tooth procedure (also referred to as an implant or an implant procedure) varies depending on the type of fixture, but it is general that the implant is completed by perforating a placement position using a predetermined drill, placing a fixture into the alveolar bone to be osseously integrated on the bone, coupling the abutment to the fixture, and then covering the abutment with a final prosthesis.

A dental implant improves the function of dentures in partial and total toothless patients as well as single absent-tooth restoration, improves the aesthetic aspects of dental prosthesis restoration, and helps to stabilize dentition while dispersing excessive stress applied to the surrounding supporting bone tissue.

Such a dental implant generally includes a fixture to be placed as an artificial dental root, an abutment coupled onto the fixture, an abutment screw to fix the abutment to the fixture, and an artificial tooth coupled to the abutment. Here, the abutment is coupled to the fixture to maintain the coupling state before the abutment is coupled to the fixture, that is, until the fixture is osseously integrated to the alveolar bone.

A fixture, which is a component of a dental implant, is a portion to be placed into a drill hole formed in the alveolar bone using a drill or the like at a position where the implant is performed, and serves as an artificial tooth root. A threaded portion is provided around the outer wall of the fixture in a helical shape for firm fixation of the fixture and the alveolar bone.

In addition, the fixture is provided with an abutment insertion groove which is formed by being recessed in the longitudinal direction at the upper end and inserted with the abutment.

In the inner wall of the abutment insertion groove, an abutment and tool-coupling portion is provided in a shape fitted to the outer wall of the abutment to prevent relative rotation with respect to the fixture on the abutment and detachably coupled with a rotary tool.

Such an abutment and tool-coupling portion performs a function of receiving the rotational power of the rotary tool at the time of placing the fixture by shape-fitting the inner wall to the outer walls of the abutment and the tool and a function of stopping the relative rotation with respect to the fixture of the abutment inserted into the abutment insertion groove.

In the fixture according to the related art, the inner wall of the abutment and tool-coupling portion is provided in a hexagonal shape in a circumferential direction of the fixture. Of course, the abutment is provided with an insertion portion having a shape in which the outer wall is shape-fitted into the inner wall of the abutment and tool-coupling portion.

As described above, according to the related art, the inner wall of the abutment and tool-coupling portion of the fixture and the outer wall of the insertion portion of the abutment are provided in a hexagonal shape. Due to the characteristic of the hexagonal shape, the inner wall of the abutment and tool-coupling portion of the fixture and the outer wall of the insertion portion of the abutment are not completely brought into close contact with each other, so that a minute spacing is formed between the inner wall of the abutment and tool-coupling portion of the fixture and the outer wall of the insertion portion of the abutment.

The shaking occurs in the abutment coupled to the fixture by the spacing, and the shaking of the abutment causes the damage to the abutment or the fixture.

In order to eliminate the shaking of the abutment, it is necessary to remove the spacing space between the inner wall of the abutment and tool-coupling portion of the fixture and the outer wall of the insertion portion of the abutment. In order to remove such a spacing, the shape of the inner wall of the abutment and tool-coupling portion of the fixture needs to be changed to a polygonal shape of a conventional hexagonal shape or more.

However, if the shape of the inner wall of the abutment and tool-coupling portion of the fixture is changed to the polygonal shape of a conventional hexagonal shape or more, there is a problem in that the torque of the rotary tool is not smoothly transmitted to the fixture.

That is, when the shape of the inner wall of the abutment and tool-coupling portion of the fixture is changed to the polygonal shape of the conventional hexagonal shape or more, the length of one side of the polygonal shape becomes shorter than the length of one side of the conventional hexagonal shape, so that there is a problem in that the torque of the rotary tool is not effectively transmitted to the fixture. <CIT> discloses a fixture of a dental implant comprising: a fixture body in which a screw portion is formed in a spiral shape along an outer wall and an abutment insertion groove inserted with an abutment is recessed in a longitudinal direction at an upper end; an abutment rotation stopping portion which is formed in a shape in which at least a part of an inner wall of the fixture body is shape-fitted to the outer wall of the abutment and stops a relative rotation to the fixture body of the abutment; and a tool coupling portion which is provided in the fixture body adjacently to the abutment rotation stopping portion of the abutment rotation stopping portion and detachably coupled with a rotary tool rotating the fixture body, whereby an inner wall of the abutment rotation stopping portion is formed in a shape in a circumferential direction of the fixture body, and in that the tool coupling portion is provided in an upper region of the abutment rotation stopping portion, and a groove portion which is connected to the protrusion portion and recessed by a predetermined depth toward the outer wall of the fixture body in the inner wall of the protrusion portion. <CIT> discloses a fixture of a dental implant comprising: a fixture body in which a screw portion is formed in a spiral shape along an outer wall and an abutment insertion groove inserted with an abutment is recessed in a longitudinal direction at an upper end; an abutment rotation stopping portion which is formed in a shape in which at least a part of an inner wall of the fixture body is shape-fitted to the outer wall of the abutment and stops a relative rotation to the fixture body of the abutment; and a tool coupling portion which is provided in the fixture body and detachably coupled with a rotary tool rotating the fixture body, whereby an inner wall of the abutment rotation stopping portion is formed in an octagonal shape in a circumferential direction of the fixture body. <CIT> discloses a fixture of a dental implant comprising: a fixture body in which a screw portion is formed in a spiral shape along an outer wall and an abutment insertion groove inserted with an abutment is recessed in a longitudinal direction at an upper end; an abutment rotation stopping portion which is formed in a shape in which at least a part of an inner wall of the fixture body is shape-fitted to the outer wall of the abutment and stops a relative rotation to the fixture body of the abutment; and a tool coupling portion which is provided in the fixture body adjacently to the abutment rotation stopping portion of the abutment rotation stopping portion and detachably coupled with a rotary tool rotating the fixture body, whereby an inner wall of the abutment rotation stopping portion is formed in a shape in a circumferential direction of the fixture body, and in that the tool coupling portion is provided in an upper region of the abutment rotation stopping portion, said tool coupling portion including a protrusion portion which is extended upward by a predetermined length from an edge region of the inner wall of the abutment rotation stopping portion; and a portion which is connected to the protrusion portion and recessed by a predetermined depth toward the outer wall of the fixture body in the inner wall of the protrusion portion.

Therefore, the present invention has been made in an effort to provide a fixture of a dental implant that can prevent the shaking of an abutment coupled to a fixture and effectively receive the torque of a rotary tool during a placing process of the fixture of a dental implant.

The embodiment of the present invention include the tool coupling portion which is disposed in the upper region of the abutment rotation stopping portion provided in a shape in which the inner wall is shape-fitted to the outer wall of the abutment and detachably coupled with the rotary tool rotating the fixture body. As a result, the shape of the abutment rotation stopping portion is not influenced by the shape of the rotary tool so that the shape of the inner wall of the abutment rotation stopping portion may be brought into close contact with the outer wall of the abutment. Therefore, it is possible to effectively receive the torque of the rotary tool at the time of placing the fixture of a dental implant while preventing shaking of the abutment coupled to the fixture body.

According to an aspect of the present invention, there is provided a fixture of a dental implant including: a fixture body in which a screw portion is formed in a spiral shape along an outer wall and an abutment insertion groove inserted with an abutment is recessed in a longitudinal direction at an upper end; an abutment rotation stopping portion which is formed in a shape in which at least a part of the inner wall of the fixture body is shape-fitted to the outer wall of the abutment and stops a relative rotation to the fixture body of the abutment; and a tool coupling portion which is provided in the fixture body adjacently to the abutment rotation stopping portion in an upper region of the abutment rotation stopping portion and detachably coupled with a rotary tool rotating the fixture body.

The inner wall of the abutment rotation stopping portion is formed in an octagonal shape in a circumferential direction of the fixture body.

The tool coupling portion includes a protrusion portion which is extended upward by a predetermine length from an edge region of the inner wall of the abutment rotation stopping portion; and a groove portion which is connected to the protrusion portion and recessed by a predetermined depth toward the outer wall of the fixture body in the inner wall of the protrusion portion.

A length of the protrusion portion in the circumferential direction of the fixture body may be smaller than a length of one side of an octagonal shape formed by the inner wall of the abutment rotation stopping portion.

Four protrusion portions may be provided and symmetrically disposed based on a virtual central axis of the fixture body.

An upper end of the protrusion portion may be formed in an obliquely inclined shape so that an inner diameter of the abutment insertion groove is increased toward an upper side.

A longitudinal length of the protrusion portion may be smaller than a longitudinal length of the abutment rotation stopping portion.

A length of the groove portion in the circumferential direction of the fixture body may be larger than a length of one side of an octagonal shape formed by the inner wall of the abutment rotation stopping portion.

Four groove portions may be provided and symmetrically disposed based on a virtual central axis of the fixture body.

The fixture body may include tapered portion which is disposed in an upper region of the abutment rotation stopping portion and provided so that the inner wall is tapered so that an inner diameter of the abutment insertion groove is gradually decreased toward the lower end of the fixture body from the upper end of the fixture body, and the tool coupling portion may include a tool coupling groove portion which is provided in the tapered portion and recessed by a predetermined depth toward the outer wall of the fixture body in the inner wall of the tapered portion.

A length of the tool coupling groove portion in the circumferential direction of the fixture body may be smaller than a length of one side of an octagonal shape formed by the inner wall of the abutment rotation stopping portion.

A height of a side wall forming the tool coupling groove portion may be increased downward.

Eight tool coupling groove portions may be provided and symmetrically disposed based on a virtual central axis of the fixture body.

The fixture body may further include an abutment support portion which is connected to the abutment rotation stopping portion, disposed in a lower region of the abutment rotation stopping portion, and supports the abutment.

The fixture body may further include a screw fastening portion which is connected to the abutment support portion, disposed in the lower region of the abutment rotation stopping portion, and provided with a screw groove which is formed in a longitudinal direction of the fixture body on the bottom of the abutment support portion to be fastened with an abutment screw coupling the abutment to the fixture body.

In order to sufficiently appreciate the present invention, operational advantages of the present invention, objects achieved by exemplary embodiments of the present invention, some of the accompanying drawings illustrating the exemplary embodiments of the present invention and contents disclosed in the accompanying drawings should be referred.

Hereinafter, preferred exemplary embodiments will be described in detail with reference to the accompanying drawings. However in description of the present invention, the description for known functions or configurations will be omitted in order to clarify the gist of the present invention.

<FIG> is a diagram schematically illustrating a process of placing a fixture of a dental implant according to a first embodiment of the present invention, <FIG> is a diagram illustrating the fixture of the dental implant of <FIG>, <FIG> is a front view of <FIG>, <FIG> is a plan view of <FIG>, <FIG> is a cross-sectional view taken along line A-A of <FIG>, <FIG> is a cross-sectional view taken along line B-B of <FIG>, <FIG> is a cross-sectional view taken along line C-C of <FIG>, and <FIG> is a cross-sectional view taken along line D-D of <FIG>.

As illustrated in <FIG>, a large number of teeth <NUM> are arranged in the gum <NUM>. The teeth <NUM> are a primary digesting means which crushes the food to deliver the crushed food into the stomach and may vary from person to person, but usually has about <NUM> numbers.

When one of these teeth <NUM> is lost (when the posterior tooth is missed), the lost tooth <NUM> is not only deteriorated in esthetics but also very inconvenient for chewing food.

A fixture body <NUM> is placed as a means for replacing a tooth root <NUM> of the tooth <NUM> on the gum <NUM> of the lost tooth <NUM>. Although not illustrated in detail in <FIG>, the fixture body <NUM> is placed into an alveolar bone (not illustrated) in the gum <NUM>, and a drilling operation is preceded for the placement of the fixture body <NUM> before the fixture body <NUM> is placed. That is, a drilled groove G is processed at a predetermined position of the alveolar bone (not illustrated).

The fixture body <NUM> may be made of titanium (Ti) or a titanium (Ti) alloy without an adverse reaction to the human body.

For reference, the fixture body <NUM> of the present embodiment to be described below may be used in an initial implant procedure, or may be used for emergency when being placed directly into the alveolar bone (not illustrated) without replenishing a predetermined bone replacement material in a damaged portion during a procedure failure.

The fixture body <NUM> is provided with an abutment insertion groove H1 (see <FIG>) which is recessed in a longitudinal direction at the upper end to be inserted with the abutment (not illustrated). When describing the structure of the fixture body <NUM> according to the present embodiment, as illustrated in <FIG>, the fixture body <NUM> according to the present embodiment includes an abutment rotation stopping portion <NUM> which stops a relative rotation to the fixture body <NUM> of the abutment (not illustrated), a tool coupling portion <NUM> which is disposed adjacently to the abutment rotation stopping portion <NUM> in an upper region of the abutment rotation stopping portion <NUM>, a tapered portion <NUM> disposed in the upper region of the tool coupling portion <NUM>, an abutment support portion <NUM> disposed in a lower region of the abutment rotation stopping portion <NUM>, and a screw fastening portion <NUM> disposed in a lower region of the abutment support portion <NUM>.

The abutment rotation stopping portion <NUM> is provided in shape in which an inner wall <NUM> forming the abutment insertion groove H1 is shape-fitted to the outer wall of the abutment (not illustrated). The abutment rotation stopping portion <NUM> stops the abutment (not illustrated) inserted into the abutment insertion groove H1 to relatively rotate to the fixture body <NUM>.

The inner wall <NUM> of the abutment rotation stopping portion <NUM> is formed in a polygonal shape in a circumferential direction of the fixture body <NUM>, and in the present embodiment, the inner wall <NUM> of the abutment rotation stopping portion <NUM> is formed in an octagonal shape in the circumferential direction of the fixture body <NUM> as illustrated in detail in <FIG>.

As such, the inner wall <NUM> of the abutment rotation stopping portion <NUM> is formed in an octagonal shape, and a length of one side forming the octagonal shape is smaller than that of one side of a conventional hexagonal shape. Accordingly, a spacing between the inner wall <NUM> of the abutment rotation stopping portion <NUM> and the outer wall of the abutment (not illustrated) is further minimized to prevent shaking of the abutment (not illustrated) coupled to the fixture body <NUM>.

The tool coupling portion <NUM> is connected to the abutment rotation stopping portion <NUM> and disposed adjacently to the abutment rotation stopping portion <NUM> in the upper area of the abutment rotation stopping portion <NUM>. A rotary tool (not illustrated) rotating the fixture body <NUM> is detachably coupled to the tool coupling portion <NUM>. In the present embodiment, a dental handpiece is used as the rotary tool (not illustrated), and the scope of the present invention is not limited thereto, and various tools which are placed into the alveolar bone (not illustrated) by rotating the fixture body <NUM> may be used as the rotary tool (not illustrated) of the present embodiment.

As such, in the present embodiment, the rotary tool (not illustrated) is coupled to the tool coupling portion <NUM> which is spatially separated from the abutment rotation stopping portion <NUM> so that the shape of the abutment rotation stopping portion <NUM> is not influenced by the shape of the rotary tool (not illustrated). Unlike the related art, the shape of the inner wall <NUM> of the abutment rotation stopping portion <NUM> may be changed to a shape (an octagonal shape of the present embodiment) which may be brought into close contact with the outer wall of the abutment (not illustrated).

As described above, the fixture body <NUM> according to the present embodiment receives a torque that rotates the fixture body <NUM> through the tool coupling portion <NUM> spatially separated from the abutment rotation stopping portion <NUM>. As a result, unlike the related art, the torque transmission of the rotary tool (not illustrated) is not influenced by the shape of the abutment rotation stopping portion <NUM> so that the torque of the rotary tool (not illustrated) may be effectively transmitted to the fixture body <NUM> in the placement of the fixture body <NUM>.

In the present embodiment, as illustrated in detail in <FIG>, the tool coupling portion <NUM> includes a protrusion portion <NUM> extended upward from an edge region of the inner wall <NUM> of the abutment rotation stopping portion <NUM> by a predetermined length, and a groove portion <NUM> which is connected to the protrusion portion <NUM> and recessed by a predetermined depth in an outer wall direction of the fixture body <NUM> at the inner wall of the protrusion portion.

In the present embodiment, the protrusion portion <NUM> and the groove portion <NUM> constitute a part of the inner wall of the abutment insertion groove H1. The groove portion <NUM> is formed so that a part of the rotary tool (not illustrated) is insertable and the protrusion portion <NUM> supports a part of the rotary tool (not illustrated) inserted into the groove portion <NUM> in the circumferential direction to prevent the rotary tool (not illustrated) from slipping in the abutment insertion groove H1, so that the torque of the rotary tool (not illustrated) is effectively transmitted to the fixture body <NUM> during the placement of the fixture body <NUM>.

When describing the structure of the protrusion portion <NUM> described above in detail, the protrusion portion <NUM> is extended upward from the edge region of the inner wall <NUM> of the abutment rotation stopping portion <NUM> by a predetermined length. The inner wall of the protrusion portion <NUM> forms the same plane as the inner wall <NUM> of the abutment rotation stopping portion <NUM> as illustrated in detail in <FIG>.

An upper end of the protrusion portion <NUM> is formed in an obliquely inclined shape as illustrated in detail in <FIG>. That is, the upper end of the protrusion portion <NUM> is formed in an obliquely inclined shape so that an inner diameter of the abutment insertion groove H1 is increased toward the upper side.

As such, the upper end of the protrusion portion <NUM> of the present embodiment is formed in an obliquely inclined shape so that an inner diameter of the abutment insertion groove H1 is increased toward the upper side, thereby naturally inducing the descending of the abutment (not illustrated) in the insertion of the abutment (not illustrated).

A circumferential length J of the protrusion portion <NUM> is smaller than a length W of one side of the inner wall <NUM> of the abutment rotation stopping portion <NUM>. That is, as illustrated in detail in <FIG>, a circumferential length J of the protrusion portion <NUM> in the circumferential direction of the fixture body <NUM> is smaller than a length W of one side of an octagonal shape formed by the inner wall <NUM> of the abutment rotation stopping portion <NUM>. The circumferential length J of the protrusion portion <NUM> induces the shape of the groove portion <NUM> having a relatively long length K (see <FIG>).

Also, as illustrated in detail in <FIG> and <FIG>, a longitudinal length of the protrusion portion <NUM> is provided to be smaller than the longitudinal length of the abutment rotation stopping portion <NUM>.

A plurality of protrusion portions <NUM> is provided and symmetrically disposed based on a virtual central axis (not illustrated) of the fixture body <NUM>. As illustrated in detail in <FIG>, in the present embodiment, four protrusion portions <NUM> are provided, and the scope of the present invention is not limited thereto, and the protrusion portion <NUM> of the present embodiment may be provided with various numbers.

The groove portion <NUM> is connected to the protrusion portion <NUM>. The groove portion <NUM> is recessed by the predetermined depth in the outer wall direction of the fixture body <NUM> at the inner wall of the protrusion portion <NUM>.

In the present embodiment, as illustrated in detail in <FIG>, the groove portion <NUM> is elongated in a circumferential direction of the fixture body <NUM>. In the present embodiment, a length K of the groove portion <NUM> in the circumferential direction of the fixture body <NUM> is larger than a length W of one side of an octagonal shape formed by the inner wall <NUM> of the abutment rotation stopping portion <NUM>.

As such, the groove portion <NUM> of the present embodiment is elongated in the circumferential direction of the fixture body <NUM> to stably support the rotary tool (not illustrated) during the coupling of the rotary tool (not illustrated).

A plurality of groove portions <NUM> is provided and symmetrically disposed based on a virtual central axis (not illustrated) of the fixture body <NUM>. As illustrated in detail in <FIG>, in the present embodiment, four groove portions <NUM> are provided, and the scope of the present invention is not limited thereto, and the groove portions <NUM> of the present embodiment may be provided with various numbers.

Meanwhile, the tapered portion <NUM> is disposed in the upper region of the tool coupling portion <NUM>. As illustrated in detail in <FIG> and <FIG>, in such a tapered portion <NUM>, an inner wall <NUM> forms the abutment insertion groove H1 and the inner wall <NUM> is tapered so that a diameter of the abutment insertion groove H1 is gradually decreased toward the lower end of the fixture body <NUM> from the upper end of the fixture body <NUM>.

An inclined angle of the inner wall <NUM> of the tapered portion <NUM> may have a range of <NUM>° to <NUM>° and a portion of the abutment (not illustrated) being in contact with the inner wall <NUM> of the tapered portion <NUM> is inclined at the same angle as the inclined angle of the inner wall <NUM> of the tapered portion <NUM>. Accordingly, the abutment (not illustrated) inserted into the abutment insertion groove H1 may be brought into close contact with the fixture body <NUM>.

In an outer region of the upper end of the fixture body <NUM>, a rounded bevel portion <NUM> is provided. The bevel portion <NUM> is a portion where the upper surfaces of the fixture body <NUM> and the alveolar bone (not illustrated) come into contact with each other when the abutment (not illustrated) is coupled to the fixture body <NUM> and serves to provide strong fixing force due to a contact in a larger area by increasing a contact area with the alveolar bone (not illustrated).

The bevel portion <NUM> is formed in a round shape having no edged portion in which an outer surface is rounded to reduce a load applied to the alveolar bone (not illustrated) during the placement of the fixture body <NUM>, thereby reducing a bone loss.

Meanwhile, as illustrated in detail in <FIG> and <FIG>, a maximum diameter of the bevel portion <NUM> is smaller than that of a screw portion S. As a result, during the placement of the fixture body <NUM>, it is possible to reduce a load applied to the alveolar bone (not illustrated) and reduce the bone loss, and a separate placement mechanism for the bevel portion <NUM> is not required.

Meanwhile, in the present embodiment, the bevel portion <NUM> is anodized to provide a much better effect than existing products in terms of strength and abrasion resistance. In addition, by anodizing, the bevel portion <NUM> may obtain coloring and smooth surface effects and has an excellent aesthetical effect.

The anodizing will be briefly described. When a metal (component) is placed on an anode and electrolyzed in a dilute-acid solution, an oxide film (aluminum oxide: Al2O3) having a great adhesion with a base metal is formed by oxygen generated in the anode. The anodic oxidation is anodizing, a compound word of anode and oxidizing. In electroplating, there is a difference from plating when a component is applied on a cathode. The most representative material of anodic oxidation is Al, and anodizing is also performed on metal materials such as Mg, Zn, Ti, Ta, Hf and Nb. In recent years, the anodizing treatment on magnesium and titanium materials is also increasingly used.

Meanwhile, the abutment support portion <NUM> is disposed in the lower region of the abutment rotation stopping portion <NUM> to be connected to the abutment rotation stopping portion <NUM>. The inner wall <NUM> of the abutment support portion <NUM> supports the abutment (not illustrated).

In the present embodiment, the inner wall <NUM> of the abutment support portion <NUM> forms the abutment insertion groove H1 and is formed in a circular shape in the circumferential direction of the fixture body <NUM> unlike the abutment rotation stopping portion <NUM>.

As such, the inner wall <NUM> of the abutment support portion <NUM> of the present embodiment is formed in a circular shape to minimize a spacing between the inner wall <NUM> of the abutment support portion <NUM> and the outer wall of the abutment (not illustrated), thereby preventing shaking of the abutment (not illustrated) coupled to the fixture body <NUM>.

Meanwhile, the screw fastening portion <NUM> is disposed in the lower region of the abutment support portion <NUM> to be connected to the abutment support portion <NUM>. The screw fastening portion <NUM> is provided with a screw groove H2 which is formed in a longitudinal direction of the fixture body <NUM> on the bottom of the abutment support portion <NUM> and fastened with an abutment screw (not illustrated) coupling the abutment (not illustrated) to the fixture body <NUM>.

The screw groove H2 is a portion which is fastened with the abutment screw (not illustrated) passing through a through hole (not illustrated) provided in the abutment (not illustrated).

Meanwhile, as illustrated in detail in <FIG>, the fixture body <NUM> of the present embodiment is formed in a tapered shape so that a diameter gradually decreases in a direction in which at least a part of the outer wall is placed.

As described above, the fixture body <NUM> according to the present embodiment is formed in a tapered shape in which the diameter of the outer wall gradually decreases in the placed direction to be stably formed in a similar structure to natural teeth and suppress bone heating generated during placement, thereby facilitating the placement and increasing the initial fixing force.

Meanwhile, in the fixture body <NUM> of the present embodiment, the screw portion S formed in a spiral shape along the outer wall is provided. Such a screw portion S is fastened to a female screw portion (not illustrated) formed on the alveolar bone (not illustrated) to firmly fix the fixture body <NUM> to the alveolar bone (not illustrated).

Further, in the fixture body <NUM> of the present embodiment, a cutting edge E formed in a circumferential direction is provided. The cutting edge E forms a sharp front end to more facilitate the placement of the fixture body <NUM>.

Referring to <FIG>, the cutting edge E of the present embodiment is provided to have a groove shape having a circular cut cross section. However, when the cutting edge E is provided in a straight groove shape, the sharp front end is embossed to increase a resistance force at the time of placing the alveolar bone (not illustrated), and the shape of the screw portion S is decreased to reduce the surface area, and thus a coupling force to the alveolar bone (not illustrated) is lowered.

Like the present embodiment, the cutting edge E formed in the groove shape enlarges the surface area of the screw portion S to improve the coupling force at the time of placing the fixture body <NUM>, thereby enhancing an initial fixing force.

In the present embodiment, three cutting edges E are provided at equal intervals along the circumferential direction of the fixture body <NUM>, and the scope of the present invention is not limited thereto, and if necessary, the number of cutting edges E may not be added or subtracted.

Hereinafter, an operation of the fixture body <NUM> of the dental implant of the present embodiment will be described with reference to <FIG>.

First, when describing a process of placing the fixture body <NUM> to the alveolar bone (not illustrated), the rotary tool (not illustrated) is coupled to the tool coupling portion <NUM> located in the upper region of the abutment rotation stopping portion <NUM> and then the fixture body <NUM> is placed into the drilled hole G illustrated in <FIG>.

At this time, the groove portion <NUM> is inserted with a part of the rotary tool (not illustrated) and the protrusion portion <NUM> supports a part of the rotary tool (not illustrated) inserted into the groove portion <NUM> in the circumferential direction to prevent the rotary tool (not illustrated) from slipping in the abutment insertion groove H1, so that the torque of the rotary tool (not illustrated) is effectively transmitted to the fixture body <NUM> during the placement of the fixture body <NUM>.

Thereafter, the abutment (not illustrated) is inserted into the abutment insertion groove H1. At this time, the inner wall <NUM> of the abutment rotation stopping portion <NUM> is shape-fitted to the outer wall of the abutment (not illustrated) so that the relative rotation to the fixture body <NUM> of the abutment (not illustrated) is stopped.

In the present embodiment, the inner wall <NUM> of the abutment rotation stopping portion <NUM> and the outer wall of the abutment (not illustrated) are formed in octagonal shapes to be brought into close contact with each other so as to have almost no spacing as compared with a case where the inner wall <NUM> of the abutment rotation stopping portion <NUM> and the outer wall of the abutment (not illustrated) are formed in a hexagonal shape in the related art. As such, the inner wall <NUM> of the abutment rotation stopping portion <NUM> is brought into close contact with the outer wall of the abutment (not illustrated) to prevent shaking of the abutment (not illustrated) coupled to the fixture body <NUM>.

According to the present embodiment, the fixture body <NUM> of the dental implant includes the tool coupling portion <NUM> which is disposed in the upper region of the abutment rotation stopping portion <NUM> in a shape in which the inner wall <NUM> is shape-fitted to the outer wall of the abutment (not illustrated) and detachably coupled with the rotary tool (not illustrated) rotating the fixture body <NUM>. As a result, the shape of the abutment rotation stopping portion <NUM> is not influenced by the shape of the rotary tool (not illustrated) so that the shape of the inner wall <NUM> of the abutment rotation stopping portion <NUM> may be brought into close contact with the outer wall of the abutment (not illustrated). Therefore, it is possible to effectively receive the torque of the rotary tool (not illustrated) at the time of placing the fixture body <NUM> while preventing shaking of the abutment (not illustrated) coupled to the fixture body <NUM>.

<FIG> is a diagram illustrating a dental implant, <FIG> is a front view of <FIG>, <FIG> is a plan view of <FIG>, <FIG> is a cross-sectional view taken along line M-M of <FIG>, <FIG> is a cross-sectional view taken along line P-P of <FIG>, and <FIG> is a cross-sectional view taken along line Q-Q of <FIG>.

The present embodiment is different from the first embodiment only in that a tool coupling portion <NUM> is provided in a tapered portion <NUM>, but other configurations are the same as those of the first embodiment of <FIG>, and thus hereinafter the same configurations use the same reference numerals and the description thereof will be omitted.

As illustrated in <FIG>, the tapered portion <NUM> is disposed in the upper region of an abutment rotation stopping portion <NUM> and a tool coupling portion <NUM> is provided in the tapered portion <NUM>.

The tool coupling portion <NUM> includes a tool coupling groove portion <NUM> which is recessed by a predetermined depth toward an outer wall of a fixture body <NUM> in an inner wall <NUM> of the tapered portion <NUM>.

The tool coupling groove portion <NUM> is formed so that a part of the rotary tool (not illustrated) is insertable and a side wall of the tool coupling groove portion <NUM> supports a part of the rotary tool (not illustrated) inserted into the tool coupling groove portion <NUM> in the circumferential direction to prevent the rotary tool (not illustrated) from slipping in the abutment insertion groove H1, so that the torque of the rotary tool (not illustrated) is effectively transmitted to the fixture body <NUM> during the placement of the fixture body <NUM>.

A length F between both side walls of the tool coupling groove portion <NUM> is smaller than a length W of one side of an inner wall <NUM> of the abutment rotation stopping portion <NUM>. That is, as illustrated in detail in <FIG>, a length F of the tool coupling groove portion <NUM> in the circumferential direction of the fixture body <NUM> is smaller than a length W of one side of an octagonal shape formed by the inner wall <NUM> of the abutment rotation stopping portion <NUM>.

Further, the tool coupling groove portion <NUM> is formed in a direction of vertically cutting the tapered portion <NUM>. Accordingly, as illustrated in <FIG>, a height of a side wall R forming the tool coupling groove portion <NUM> is increased downward.

A plurality of tool coupling groove portions <NUM> is provided and symmetrically disposed based on a virtual central axis (not illustrated) of the fixture body <NUM>. As illustrated in detail in <FIG>, eight tool coupling groove portions <NUM> are provided, and the scope of the present invention is not limited thereto, and the tool coupling groove portions <NUM> may be provided with various numbers.

As such, the fixture body <NUM> of the dental implant has an advantage of maximizing space utilization by providing the tool coupling groove portions <NUM> in the tapered portion <NUM>.

Claim 1:
A fixture of a dental implant comprising:
a fixture body (<NUM>) in which a screw portion (S) is formed in a spiral shape along an outer wall and an abutment insertion groove (H1) inserted with an abutment is recessed in a longitudinal direction at an upper end;
an abutment rotation stopping portion (<NUM>) which is formed in a shape in which at least a part of an inner wall of the fixture body (<NUM>) is shape-fitted to the outer wall of the abutment and stops a relative rotation to the fixture body (<NUM>) of the abutment;
a protrusion portion (<NUM>) which is extended upward by a predetermined length from an edge region of the inner wall of the abutment rotation stopping portion (<NUM>); and
a tool coupling portion (<NUM>) which is provided in the fixture body (<NUM>) adjacently to the abutment rotation stopping portion (<NUM>) of the abutment rotation stopping portion (<NUM>) and detachably coupled with a rotary tool rotating the fixture body (<NUM>), said tool coupling portion (<NUM>) including a groove portion (<NUM>) which is connected to the protrusion portion (<NUM>) and recessed by a predetermined depth toward the outer wall of the fixture body (<NUM>) in the inner wall of the protrusion portion (<NUM>),
characterized in that
an inner wall of the abutment rotation stopping portion (<NUM>) is formed in an octagonal shape in a circumferential direction of the fixture body (<NUM>),
the tool coupling portion (<NUM>) is provided in an upper region of the abutment rotation stopping portion (<NUM>),
said tool coupling portion (<NUM>) additionally includes the protrusion portion (<NUM>),
the inner wall of the protrusion portion (<NUM>) forms the same plane as the inner wall (<NUM>) of the abutment rotation stopping portion (<NUM>),
a length of the protrusion portion (<NUM>) in the circumferential direction of the fixture body (<NUM>) is smaller than a length of one side of an octagonal shape formed by the inner wall of the abutment rotation stopping portion (<NUM>),
four protrusion portions (<NUM>) are provided and symmetrically disposed based on a virtual central axis of the fixture body (<NUM>), and, in that
a length of the groove portion (<NUM>) in the circumferential direction of the fixture body (<NUM>) is larger than a length of one side of the octagonal shape formed by the inner wall of the abutment rotation stopping portion (<NUM>).