WO2010139041A1

WO2010139041A1 - Dental implant

Info

Publication number: WO2010139041A1
Application number: PCT/BY2009/000008
Authority: WO
Inventors: Anatoli D. Dosta; Bernhard SCHRÖEDER
Original assignee: Joint Stock Company 'altimed'
Priority date: 2009-06-01
Filing date: 2009-06-01
Publication date: 2010-12-09

Abstract

The invention is related to implant dentistiy and, in particular, to dental implants intended for integration into a jawbone. A dental implant comprises an abutment for making-up a tooth prosthesis and a surface in contact with osseous-tissue which is comprised of a bio-compatible metal porous area for ingrowth of a jawbone. Said implant also comprises an annual collar for ingrowth of gingival soft tissue made in the form of a surface porous three-dimensional structure from polytetrafluorethylene located between a tooth prosthesis abutment and a bio-compatible metal porous area, while a bio-compatible metal porous area is made in the form of a three-dimensional structure with the possibility of a press fit into a jawbone.

Description

DENTAL IMPLANT

The invention is related to implant dentistry and, in particular, to dental implants intended for integration into a jawbone.

A common clinical problem associated with dental implants is the destruction of a jawbone at a distal (coronal) side of an implant. The bone destruction of the kind is caused by infectious etiology like the one that occurs in the course of periodontal disease of the original teeth. The relationship between pathogenic bacteria of periodontal tissues and the destruction of a jawbone calls in the fist place for the necessity of careful oral hygiene and also for the possibility of preventing the disease and treatment of the problem implantation area by the dentist. Therefore implants with a smooth surface at a distal end portion are the most preferred choice in clinical dentistry. A smooth surface at a distal end portion of a dental implant can be easily cleaned from a dental deposit, pathogenic bacteria and endotoxins. It also improves the accuracy of attachment between an implant and a tooth prosthesis abutment which prevents in future the formation of a loose space between said components that would become a favorable area for the accumulation of pathogenic bacteria. However, a smooth surface at a distal end portion of an implant though being in contact with a jawbone does not provide the attachment to the latter. To provide the engagement of an implant surface with a jawbone said surface is made a rough one. To improve the integration of osseous tissue with a dental implant the implant surface in the area of its contact with said osseous tissue is made a porous one from sintered metal powder, mesh or balls. However, since a porous surface is easily affected by the bacteria migrating from an oral cavity, it causes the invasion of infection through the pores of said porous surface into osseous tissue, the latter resulting in the destruction of a jawbone into which a dental implant has been integrated.

Known is an implant with a porous surface (US Patent No. 5,344,457) which is comprised of a bottom area adjoining a jawbone and having a porous surface for ingrowth of a jawbone and an upper area adjoining a jawbone and having a non-porous smooth surface, which a jawbone is in direct contact with. Placing an implant area, which is in direct contact with a jawbone, above an implant porous surface makes it possible to prevent a direct migration of pathogenic bacteria from an oral cavity into a porous surface, though it does not prevent an invasion of infection into an implantation area.

Known is an implant for integration into a jawbone (WO 9721393 Al) comprised of an elongated framework having a distal end portion for attachment of a tooth prosthesis abutment and a composite textured surface made up of three areas and contacting osseous tissue. The first one is a porous biocompatible metal surface area for ingrowth of osseous tissue. The second one is a non-porous bio-compatible rough metal surface area positioned between a porous area and a distal framework end portion and providing the engagement with a jawbone due to its surface roughness. The third one is a non-porous bio- compatible smooth metal surface area positioned between a rough surface and a distal end portion. Due to the fact that the engagement of a jawbone with an implant occurs above the level of a porous surface, the latter appears to be closed for the migration of pathogenic bacteria from an oral cavity. A smooth surface area at a distal end portion of an implant, which is in contact with periodont, provides the possibility of removing accumulation of bacteria.

However, since a smooth surface area at an implant distal end portion is not engaged with periodont, there still exists the possibility of migration of pathogenic bacteria from an oral cavity into an implantation area. To prevent such migration a careful cleaning from the deposit and elimination of bacteria accumulation in the contact area of a smooth surface with periodont are required. Besides, since the gingival epithelial cells are not fused with said smooth surface, placement of an implant into a jawbone is not as rigid as it is desired. The use of a porous structure for osseous tissue ingrowth only in the portion of a surface area does not provide a complete fusion of osseous tissue, thus failing to achieve a rigid placement and a reliable attachment of a dental implant into a jawbone.

It is the aim of the present invention to provide a sound protection of an implantation area from invasion of infection from an oral cavity due to hermetic attachment of an implant distal end portion to periodont and also to improve the durability of attachment and the rigidity of placement of a dental implant into a jawbone.

The above aim is achieved by means of a dental implant comprising an abutment for making-up a tooth prosthesis and a surface in contact with osseous- tissue which is comprised of a bio-compatible metal porous area for ingrowth of a jawbone, wherein said implant also comprises an annual collar for ingrowth of gingival soft tissue made in the form of a surface porous three-dimensional structure from polytetrafluorethylene located between a tooth prosthesis abutment and a bio-compatible metal porous area, while a bio-compatible metal porous area is made in the form of a three-dimensional structure with the possibility of a press fit into a jawbone.

Besides, a metal porous three-dimensional structure is shaped as a rotaiy body.

A metal porous three-dimensional structure could also be shaped as a plate.

Besides, a metal porous three-dimensional structure is made from titanium powder.

A metal porous three-dimensional structure presents a framework with a titanium powder forced thereon.

A metal porous three-dimensional structure is made with a pore size ranging from 150 to 300 μm.

The height of the annual collar for ingrowth of gingival soft tissue corresponds to the thickness of said gingival soft tissue. It could be explained by the fact that once a complete ingrowth of epithelial cells into a surface porous three-dimensional structure of the annual collar from polytetrafluorethylene occurs, a hermetic attachment of an implant with soft tissues is completed, thus making a reliable protection for migration of pathogenic bacteria into an implantation area from an oral cavity and improving the durability of attachment and the rigidity of placement of an implant into a jawbone. A three-dimensional structure of a bio-compatible metal porous area at that provides a complete ingrowth of osseous tissue and thus generates a permanent attachment of an implant to a jawbone.

The invention is further explained by means of the following drawings, where

Fig. 1 is a general view of a dental implant having a cylinder-shaped metal porous three-dimensional structure;

Fig. 2 is a sectional view of a dental implant having a cylinder-shaped metal porous three-dimensional structure;

Fig. 3 is a general view of a dental implant having a plate-shaped metal porous three-dimensional structure;

Fig. 4 is a sectional view of a dental implant having a plate-shaped metal porous three-dimensional structure.

One of the embodiments of a dental implant according to the invention is illustrated in Fig. 1 and Fig. 2. A dental implant made from a bio-compatible material such a titanium is shaped as a cylinder body having a proximal end portion and a distal end portion. Within the scope of the present description a term "proximal" means directed towards a jawbone foramen during implantation procedure, while a term "distal" respectively means directed towards an oral cavity. A dental implant according to the invention is comprised of a biocompatible metal area which is in contact with osseous tissue and presents a cylinder-shaped three-dimensional porous structure 1 having a hemisphere curvature at its proximal end portion. A three-dimensional porous structure 1 is made from titanium powder forced on a framework 2 and produced from titanium sponge by a hydrostatic pressing method (See Vityaz P. A. et al. Porous Powder Materials and Products thereof, Minsk, "Vyshejshaja Shkola", 1987, p. 115). A dental implant is comprised of an annual collar 3 for ingrowth of gingival soft tissue which is made in the form of a bush positioned between a three-dimensional metal porous structure 1 and an abutment 4 for making a tooth prosthesis body which is installed at an implant distal end portion and secured at a framework 2 by means of a screw 5. An annual collar 3 is made from polytetrafluorethylene and is provided with a surface porous three- dimensional structure similar to the prior art polymer surface porous three- dimensional structures (See WO 2005107829).

According to another embodiment of the invention illustrated in Fig. 3 and Fig. 4 a dental implant is comprised of a bio-compatible metal three-dimensional porous structure which is in contact with osseous tissue and is made in the form of a plate 6 from titanium powder forced on a framework 7. An annual collar 8 for ingrowth of gingival soft tissue is made in the form of a bush located between a metal three-dimensional porous structure 6 and an abutment 9 for making a tooth prosthesis body.

An implantation procedure is performed in the following way.

A bio-compatible metal three-dimensional porous structure shaped as a cylinder 1 or a plate 6 is inserted into a pre-formed forearm of a jawbone in such a manner that an outward surface of an annual collar 3, 8 coincides with the level of gingival soft tissue which is further stitched. An abutment 4, 9 for making a tooth prosthesis is secured in a framework 2, 7 by a screw 5, 10. After a complete fusion of an implant a tooth prosthesis is produced at an abutment 4, 9.

Due to the fact that a bio-compatible metal area contacting osseous tissue is made in the form of a three-dimensional porous structure 1 , 6 fusion of osseous ό tissue proceeds throughout its depth thus forming an integral joint with said porous structure. Thus, a bio-compatible metal three-dimensional porous structure 1, 6 appears to be reliably protected from invasion of infection from an oral cavity by means of an annual collar 3, 8 from polytetrafluorethylene having a surface porous three-dimensional structure promoting ingrowth of gingival osseous tissue.

Making a bio-compatible metal three-dimensional porous structure shaped as a rotary body or a plate provides the possibility of placing a dental implant according to the invention in various portions of the jaw irrespective of the space provided thereto.

Thus, a dental implant according to the invention reliably protects an implantation area from pathogenic bacteria migrating from an oral cavity and also provides a deep fusion of osseous tissue therein thus promoting the rigidity of placing and attachment of a dental implant into a jawbone.

Claims

The Claims

1. A dental implant comprising an abutment for making-up a tooth prosthesis and a surface in contact with osseous-tissue which is comprised of a bio- compatible metal porous area for ingrowth of a jawbone, wherein said implant also comprises an annual collar for ingrowth of gingival soft tissue made in the form of a surface porous three-dimensional structure from polytetrafluorethylene and located between a tooth prosthesis abutment and a bio-compatible metal porous area, while a bio-compatible metal porous area is made in the form of a three-dimensional structure with the possibility of a press fit into a jawbone.

2. A dental implant as in claim 1, wherein a metal porous three-dimensional structure is shaped as a body of rotation

3. A dental implant as in claim 1, wherein a metal porous three-dimensional structure is shaped as a plate.

4. A dental implant as in any of claims from 1 to 3, wherein a metal porous three-dimensional structure is made from titanium powder.

5. A dental implant as in any of claims from 1 to 3, wherein a metal porous three-dimensional structure presents a framework with titanium powder forced thereon.

6.. A dental implant as in any of claims from 1 to 5, wherein a metal porous three-dimensional structure is made with a pore size ranging from 150 to 300 μm.

7. A dental implant as in any of claims from 1 to 6, wherein the width of the annual collar for ingrowth of gingival soft tissue corresponds to the thickness of said gingival soft tissue.