WO2007136200A1

WO2007136200A1 - Separable abutment for dental implant and method for making dental prosthesis using the same

Info

Publication number: WO2007136200A1
Application number: PCT/KR2007/002436
Authority: WO
Inventors: Seong-Gyun Oh
Original assignee: Individual
Current assignee: Individual
Priority date: 2006-05-19
Filing date: 2007-05-18
Publication date: 2007-11-29
Anticipated expiration: 2008-11-19
Also published as: KR20070112075A

Abstract

A separable abutment for a dental implant is secured to a fixture embedded in an alveolar bone to thereby retain a dental prosthesis in place. The separable abutment includes a lower member secured to the fixture, an upper member fixed to the dental prosthesis and an attachment structure for separably coupling the lower member and the upper member together.

Description

SEPARABLE ABUTMENT FOR DENTAL IMPLANT AND METHOD FOR MAKING DENTAL PROSTHESIS USING THE

SAME

Technical Field

[1] The present invention relates to a dental implant and, more particularly, to an abutment for an implant. Background Art

[2] A dental implant refers to an artificial tooth structure formed by embedding an artificial tooth root in a tooth-missing region, allowing the tooth root to adhere to an alveolar bone and fixing a dental prosthesis to the artificial tooth thus adhered. In general, the implant consists of a fixture, an abutment secured to the fixture and a dental prosthesis fixed to the abutment. Conventional implants are divided into a screw-retained implant and a cement-retained implant depending on the method of fixing a dental prosthesis.

[3] The screw-retained implant is of the type in which a dental prosthesis is fixed in place by a screw, one representative example thereof being shown in Fig. 1. Referring to Fig. 1, an implant 10a includes a fixture 20a, a UCLA abutment 30a and a dental prosthesis 40a. The fixture 20a is embedded in an alveolar bone 90a and the UCLA abutment 30a is integrated with the dental prosthesis 40a and secured to the fixture 20a by means of a fixing screw 50a.

[4] Shown in Fig. 2 is a structure of the conventional cement-retained implant.

Referring to Fig. 2, an implant 10c includes a fixture 20c, an abutment 30c and a dental prosthesis 40c. The fixture 20c is embedded in an alveolar bone 90c and the abutment 30c is secured to the fixture 20c by virtue of a fixing screw 50c. The dental prosthesis 40c is fitted to the abutment 30c thus secured and is bonded and fixed thereto with dental cement 100c.

[5] The screw-retained implant shown in Fig. 1 allows the dental prosthesis to be removed and reshaped in a relatively easy manner, if such a need arises, but requires the dental prosthesis to be machined with extremely high accuracy. For this reason, the screw-retained implant suffers from a problem in that the task of accurately producing the same is difficult, time-consuming and costly. Another problem lies in that the screw may be loosened. The cement-retained implant illustrated in Fig. 2 can be manually fixed in place more easily than the screw-retained implant and therefore can be treated in a relatively easy manner. However, the cement-retained implant poses a problem in that the task of attaching and detaching the dental prosthesis is not easy to control. In other words, it is often the case that the dental prosthesis is detached very easily or remains too firm to be separated. Disclosure of Invention

Technical Problem

[6] In view of the above-noted problems inherent in the prior art, it is an object of the present invention to provide an abutment for a dental implant that makes it possible to produce and manage a dental prosthesis of high accuracy in an easier manner.

[7] Another object of the present invention is to provide an abutment for a dental implant that allows a dental prosthesis to be attached or detached with ease.

[8] A further object of the present invention is to provide an abutment for a dental implant that allows a dental prosthesis of high accuracy to be produced with ease and thus makes it possible to attach a dental prosthesis similar to a cement attachment type one with no use of cement. Technical Solution

[9] In one aspect of the present invention, there is provided a separable abutment for a dental implant secured to a fixture embedded in an alveolar bone for retaining a dental prosthesis in place, including: a lower member secured to the fixture; an upper member fixed to the dental prosthesis; and an attachment structure for separably coupling the lower member and the upper member together.

[10] The attachment structure may include a snap fastener including a female button provided in one of the upper member and the lower member and a male button provided in the other of the upper member and the lower member.

[11] The attachment structure may include a stopper groove provided in at least one of the upper member and the lower member and a coupler ring fitted to the stopper groove, whereby the upper member and the lower member are coupled together by an elastic force of the coupler ring.

[12] The attachment structure may include a head portion provided in the lower member to taper toward a distal end and a reception space provided in the upper member to snugly receive the head portion, whereby the upper member and the lower member are coupled together by a frictional force and a negative pressure.

[13] The attachment structure may include at least two of the three attachment structures noted above.

[14] The attachment structure may include a protrusion provided in one of the upper member and the lower member and a stopper groove provided in the other of the upper member and the lower member to engage with the protrusion.

[15] In another aspect of the present invention, there is provided a method for making a dental prosthesis by using a separable abutment for a dental implant secured to a fixture embedded in an alveolar bone for retaining the dental prosthesis in place, the separable abutment comprising a lower member secured to the fixture, an upper member fixed to the dental prosthesis and an attachment structure for separably coupling the lower member and the upper member together, wherein the method comprising the steps of: separating the upper member from the lower member of the abutment and integrally forming the upper member and the dental prosthesis in a process of casting the dental prosthesis.

Advantageous Effects

[16] With a configuration of the present invention, it is possible to accomplish all the objects of the present invention set forth above. More specifically, thanks to the fact that an abutment includes an upper member and a lower member coupled together by a separable attachment structure, it is possible to separate and reattach a dental prosthesis with ease. This helps to save time and makes it quite easy to conduct post-treatment management. Furthermore, owing to the fact that the upper member is integrally formed with the dental prosthesis in the process of producing the latter, it is possible to produce a dental prosthesis of high accuracy in an easier manner. Brief Description of the Drawings

[17] Figs. IA and IB are section views illustrating a structure of a conventional screw- retained implant.

[18] Fig. 2 is a section view showing a conventional cement-retained implant.

[19] Fig. 3 is a section view showing a state that an implant using an abutment in accordance with the present invention is placed in position.

[20] Fig. 4 is an exploded perspective view of the abutment shown in Fig. 3.

[21] Fig. 5 is a section view illustrating a state that a dental prosthesis is separated from the implant shown in Fig. 3.

[22] Fig. 6 is a section view showing a state that an implant using an abutment in accordance with another embodiment of the present invention is placed in position.

[23] Fig. 7 is a section view showing a state that an implant using an abutment in accordance with a further embodiment of the present invention is placed in position.

[24] Fig. 8 is an exploded perspective view of the abutment shown in Fig. 7.

Best Mode for Carrying Out the Invention

[25] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawing.

[26] Referring to Fig. 3, an implant 10 includes a fixture 20 embedded in an alveolar bone 90, a dental prosthesis 40 and an abutment 30 fixed at its bottom to the fixture 20 and at its top to the dental prosthesis 40. A female thread portion 22 is formed inside the fixture 20. A male thread portion 68 of the abutment 30 that will be set forth below is coupled to the female thread portion 22. The dental prosthesis 40 is fixedly secured to an upper member 70 of the abutment 30 which will be set forth below.

[27] Referring to Figs. 3 and 4, the abutment 30 includes a lower member 60 fixed to the fixture 20 and an upper member 70 fixed to the dental prosthesis 40. The lower member 60 and the upper member 70 are separably coupled together by means of an attachment structure. The lower member 60 has a generally vertically extending post shape and includes a head portion 64, an enlargement portion 62 and an extension portion 66, which are formed one below another in sequence. The head portion 64 is of a generally conical shape and has an outer surface 65 gradually widening toward a bottom end, i.e., tapering toward a top end. An annular fixing groove 651 is provided on the outer surface 65 of the head portion 64. A coupler ring 80 is fitted and secured to the fixing groove 651 against removal. The coupler ring 80 may be made of rubber (plastics) or metal. A radial outer portion of the coupler ring 80 thus fitted and secured to the fixing groove 651 forms a protrusion 82 that protrudes from the outer surface 65 of the head portion 64. A below-noted stopper groove 78 of the upper member 70 engages with the protrusion 82 to provide coupling between the lower member 60 and the upper member 70. The enlargement portion 62 is enlarged outwardly farther than the head portion 64. The extension portion 66 extends long downwardly from the enlargement portion 62 and is formed of a male thread portion 68. The male thread po rtion 68 of the extension portion 66 is coupled to the female thread portion 22 of the fixture 20 embedded in the alveolar bone 90, whereby the lower member 60 of the abutment 30 is fixedly secured to the fixture 20.

[28] The upper member 70 includes a top wall 73, a side wall 72 extending downwardly from the top wall 73 and a flange portion 74 extending outwardly from a bottom end of the side wall 72. The side wall 72 and the top wall 73 cooperate to define a reception space 79 in which the head portion 64 of the lower member 60 is received. An annular stopper groove 78 is provided on an inner surface 76 of the side wall 72. The stopper groove 78 engages with the protrusion 82 of the coupler ring 80 to ensure that the upper member 70 fixed to the dental prosthesis 40 is separably coupled to the lower member 60. The dental prosthesis 40 and the upper member 70 can be integrally formed by a suitable means (e.g., a method used in producing a UCLA abutment) in a casting process of the dental prosthesis 40. It will be appreciated by those skilled in the art that the coupling force between the lower member 60 and the upper member 70 can be suitably adjusted depending on the shape of the coupler ring 80 and the stopper groove 78. The upper member 70 is preferably made of titanium but the present invention is not limited thereto.

[29] In a state that the upper member 70 and the lower member 60 is coupled together as illustrated in Fig. 4, the dental prosthesis 40 is well kept in place under the action of the coupler ring 80. If a force greater than the coupling force between the upper member 70 and the lower member 60 is applied to the dental prosthesis 40 in the state shown in Fig. 4, the upper member 70 and the lower member 60 of the abutment 30 are released from coupling and the dental prosthesis 40 is separated from the lower member 60 together with the upper member 70, which state is shown in Fig. 5. Furthermore, the dental prosthesis 40 can be coupled again to the lower member 60 by applying an appropriate force thereto in the state that the dental prosthesis 40 is kept separated as illustrated in Fig. 5. The upper member 70 and the lower member 60 need to be accurately coupled so that no foreign material can be infiltrated between them. In this way, it is possible to eliminate the need to use bonding cement.

[30] Although the fixing groove is provided in the lower member 60 and the stopper groove is formed in the upper member 70 according to the embodiment described above, it may be possible, in the opposite manner, to form the fixing groove in the upper member 70 and to provide the stopper groove in the lower member 60. It will be understood by those skilled in the art that a desired coupling force can be generated by frictional contact of the upper member with the coupler ring without having to use the stopper groove. Furthermore, although a single coupler ring is employed in the embodiment described above, the present invention is not limited thereto. Alternatively, it may be possible to use a plurality of coupler rings, in which case a plurality of stopper grooves need to be provided. Moreover, although the abutment is integrally provided with the female thread for securing the same to the fixture according to the embodiment described above, the present invention is not limited thereto. It will be understood by those skilled in the art that the separable abutment of the present invention may dispense with an integrally formed thread but may be used in combination with a separate fixing screw.

[31] In Fig. 6, there is shown an implant using an abutment in accordance with another embodiment of the present invention. Referring to Fig. 6, a lower member 6Od and an upper member 7Od of an abutment 30d are kept coupled together by virtue of a frictional force developed between the mutually contacting surfaces thereof. Furthermore, the negative pressure acting between the lower member 6Od and the upper member 7Od serves as a coupling force together with the frictional force. That is to say, the lower member 6Od and the upper member 7Od are coupled together by a snug-fitting method. It will be understood by those skilled in the art that the upper member 7Od may be separated from the lower member 6Od by applying an appropriate external force and may be coupled again to the lower member 6Od. Other configurations and operations of the present embodiment are the same as those of the preceding embodiment shown in Figs. 3 to 5. Therefore, no description will be given in that regard. [32] Referring to Figs. 7 and 8, a lower member 6Oe of an abutment 30e is fixedly secured to a fixture by a fixing screw 50e. An upwardly extending hollow shaft portion 64e is provided on a top portion of the abutment 30e. The shaft portion 64e tapers toward a distal end thereof to have a gradually decreasing inner diameter and is split by a plurality of slits 69e to form a female button 67e of a snap fastener. A jut 79e protruding downwardly from a top wall 73e is provided within an upper member 7Oe. The jut 79e is enlarged at its distal end to form a male button of a snap fastener. Thus, a snap fastener is formed by the female button 67e of the lower member 6Oe and the male button 79e of the upper member 7Oe. The snap fastener thus configured makes it easy to separably couple the upper member 7Oe and the lower member 6Oe together. A separation cutout 78e is provided at a bottom end of the upper member 7Oe that makes contact with the lower member 6Oe. A separation tool such as a screw driver or the like can be inserted into the cutout 78e to assist in separating the upper member 7Oe from the lower member 6Oe.

[33] A method of coupling an upper member and a lower member of an abutment in accordance with the present invention is not limited to the ones disclosed in the foregoing three embodiments. It will be understood by those skilled in the art that the methods of the three embodiments may be used in combination. In addition, any coupling structure that allows the upper and lower members of an abutment to be separably coupled by an appropriate force will fall within the scope of the present invention.

[34] Although not shown in the drawings, the respective abutments of the embodiments shown in Figs. 4 to 8 may include an anti-rotation structure for preventing any relative rotation between the upper member and the lower member. The anti-rotation structure may consist of, e.g., a groove and a dog engaging with the groove to prevent rotation.

[35] In the illustrated embodiments, the abutment is of an external anti-rotation type in which the anti-rotation structure for preventing the abutment from rotating with respect to the fixture is formed outside the fixture, the present invention is not limited thereto. It will be understood by those skilled in the art that the separable abutment of the present invention may be of an internal anti-rotation type in which the anti-rotation structure is formed inside the fixture.

[36] It will also be understood by those skilled in the art that the separable abutment of the present invention may be applied not only to the dental implant of the type shown in the drawings but also to other types of dental implants that make use of an abutment. Industrial Applicability

[37] As described above, a dental prosthesis is integrally formed with an upper member of an abutment beforehand so that it can be accurately coupled to a lower member. This makes it possible to perform attachment and detachment of the dental prosthesis in a controlled manner. Furthermore, the accurately-coupled separable abutment is structurally similar to that of a cement-retained dental implant but eliminates the need to use cement. Thus, the separable abutment of the present invention is more hygienic to use than the conventional ones. If necessary, lipids friendly to a living body may be used in place of cement.

[38] While the present invention has been described with reference to the embodiments noted above, the present invention is not limited thereto. It will be understood by those skilled in the art that various changes and modifications may be made without departing from the scope of the invention defined in the claims.

Claims

[1] A separable abutment for a dental implant secured to a fixture embedded in an alveolar bone for retaining a dental prosthesis in place, comprising: a lower member secured to the fixture; an upper member fixed to the dental prosthesis; and an attachment structure for separably coupling the lower member and the upper member together.

[2] The separable abutment for a dental implant as recited in claim 1, wherein the attachment structure comprises a snap fastener including a female button provided in one of the upper member and the lower member and a male button provided in the other of the upper member and the lower member.

[3] The separable abutment for a dental implant as recited in claim 1, wherein the attachment structure includes a stopper groove provided in at least one of the upper member and the lower member and a coupler ring fitted to the stopper groove, whereby the upper member and the lower member are coupled together by an elastic force of the coupler ring.

[4] The separable abutment for a dental implant as recited in claim 1, wherein the attachment structure includes a head portion provided in the lower member to taper toward a distal end and a reception space provided in the upper member to snugly receive the head portion, whereby the upper member and the lower member are coupled together by a frictional force and a negative pressure.

[5] The separable abutment for a dental implant as recited in claim 1, wherein the attachment structure includes a protrusion provided in one of the upper member and the lower member and a stopper groove provided in the other of the upper member and the lower member to engage with the protrusion.

[6] The separable abutment for a dental implant as recited in claim 1, wherein the attachment structure comprises two or more attachment structures selected from the attachment structure of claim 2, the attachment structure of claim 3 and the attachment structure of claim 4.

[7] A method for making a dental prosthesis by using a separable abutment for a dental implant secured to a fixture embedded in an alveolar bone for retaining the dental prosthesis in place, the separable abutment comprising a lower member secured to the fixture, an upper member fixed to the dental prosthesis and an attachment structure for separably coupling the lower member and the upper member together, wherein the method comprising the steps of: separating the upper member from the lower member of the abutment and integrally forming the upper member and the dental prosthesis in a process of casting the dental prosthesis.