GB2477010A

GB2477010A - Dental implant with pores

Info

Publication number: GB2477010A
Application number: GB1017709A
Authority: GB
Inventors: Eliezer Bar Shalom
Original assignee: AB Dental Devices Ltd
Current assignee: AB Dental Devices Ltd
Priority date: 2010-01-18
Filing date: 2010-10-20
Publication date: 2011-07-20
Also published as: GB201017709D0; WO2011086529A1; GB2476969A; GB201000674D0

Abstract

A dental implant 100 made by laser sintering is disclosed. At least a part of the body 110 of the implant is porous and may comprise a three dimensional lattice structure. The body 110 is produced by layer by layer laser sintering. The body 110 further comprises an inner thread 90 for attachment to an abutment and an outer thread 95 for attachment to the jaw bone. Preferably, the implant is made from titanium or a titanium alloy. The presence of pores enhances bone growth into the implant, thereby increasing the stability of the implant in the jaw. The at least partly porous body 110 may have a spatially varying density through varying the pore diameters, form and their spacing. A method of making a dental implant with a porous core is also disclosed. This method utilises layer-wise laser sintering and can be used to mass produce many implants with a single defined three dimensional structure and simultaneously different dental implants with individually tailored three dimensional structures.

Description

THREE DTMENSONAL LATTICE TMPLANT BODY

BACKGROUND

1. TECHNICAL FIELD

[0001] The present invention relates to the field of dentistry, and more particularly, to dental implants.

2. DISCUSSION OF RELATED ART [0002] Dental implants are implanted in the patients jaw in order to allow attachment of prostheses. Anchoring the dental implant in the jaw poses difficulties of bone abrasion and implant dc-stabilization as the implant stays an alien part in the jaw.

[0003] The following patents and patent applications disclose various dental implants and implantation appliances with pores or tunnels. European Patent Document No. 1133957 discloses implants with channels that promote bone ingrowth, European Patent Document No. EP1764061 discloses producing dental implants with surface cavities by laser sintering, U.S. Patent Publication No. 20030224328 discloses a hiofunctional dental implant system for affixing a crown to an implant socket, that enables the crown to have a selectively controllable mobility relative to the root portion that is anchored within the implant socket, Spanish Patent Document No. 2288437 discloses an implant having conduits for introducing substances into the surroundings of the implant, European Patent Document No. 1430843 discloses an apparatus for embedding an implant in bone tissue in a way that encourages bone tissue growth, WIPO Publication No. 2006096720 discloses an implantable dental screw, WIPO Publication No. 03073912 discloses implants constructed of a biodegradable polymer formed into a structure having micro-architectural features for in-situ application of a liquid biodegradable polymer, European Patent Document No. 1093766 discloses implants with numerous microscopic dents which increase the surface area, and European Patent Document No. 1991169 discloses laser treating the surface of implantable devices.

BRIEF SUMMARY

[0004] Embodiments of the present invention provide a dental implant having a body comprising an inner thread for connecting an abutment thereto and an outer thread for connecting the dental implant to a jaw bone, characterized in that the body is at least partially porous. The porosity structure is arranged to enhance bone growth into the body, and the dental implant is produced layer by layer by laser sintering, wherein the bone growth into the body enhances implant stability and allows for close implantation of neighbouring implants.

[0005] These, additional, and/or other aspects and/or advantages of the present invention are: set forth in the detailed description which follows; possibly inferable from the detailed description; and/or learnable by practice of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0006] The present invention will be more readily understood from the detailed description of embodiments thereof made in conjunction with the accompanying drawings of which: Figures lA-iD are high level schematic illustrations of a dental implant, according to some embodiments of the inventiom Figures 2A and 2B are high level schematic illustrations of a dental implant, according to some embodiments of the invention; and Figure 3 is a high level flowchart illustrating a method of dental implants' production, according to some embodiments of the invention.

DETAILED DESCRIPTION

[0007] Before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is applicable to other embodiments or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting.

[0008] For a better understanding of the invention, the usage of the following term in the present disclosure is defined in a non-limiting manner: [0009] The term "three dimensional lattice" as used herein in this application, is defined as a three dimensional network of material comprising spaces of various dimensions (e.g. tunnels) that penetrate the whole volume. The density of the three dimensional lattice may be uniform or variable. The spaces may be of constant or variable cross sectional form and area. The three dimensional lattice may comprise multiple adjacent two dimensional meshes such that the spaces are interconnected and characterized by the mesh opening parameters.

[0010] Figures lA-iD are high level schematic illustrations of a dental implant 100, according to some embodiments of the invention. Figure 1A is a perspective view, Figure lB is a side view, Figure 1C is a cross sectional view, and Figure 1D presents a detail marked 97 in Figure 1C which illustrates in magnification the structure of the three dimensional lattice, according to some embodiments of the invention. The three dimensional lattice is represented in Figures lA-iC in a schematic manner.

[0011] Dental implant 100 has a body 110 comprising an inner thread 90 for connecting an abutment (not shown) thereto and an outer thread 95 for connecting dental implant 100 to a jaw bone (not shown). thner thread 90 may extend to varying depths within body 110, according to the size of implant 100 and its type of connection with the abutment.

Inner thread 90 may be supported by a layer 120 of solid material, to ensure the stability of the connection to the abutment. Outer thread 95 may also be supported by a solid layer (not shown). Supporting layers (e.g. layer 120) may be either solid or have a higher density than other parts of body 110.

[0012] Dental implant 100 is characterized in that body 110 is at least partially porous, e.g. comprising a three dimensional lattice (hatched in Figures lA-iC) arranged to enhance bone growth into body 110. The porosity of body 110 is arranged to create many free trajectories through implant 110 for the bone to grow into and to occupy, resulting in a good integration of implant 110 in the jaw.

[0013] Figure 1D illustrates a possible structure of the porous core as a three dimensional lattice -interwoven or parallel layers of a two dimensional mesh, optionally with openings of different forms and sizes 115A, 115B. Openings 115A may be larger than openings 115B according to their position in implant 100 and to implantation considerations in case of tailored implants 100.

[0014] Figure 2A is high level schematic illustration of dental implant 100, according to some embodiments of the invention. Body 110 may comprise a solid part 11OA and a porous part 11OB. Figure 2B illustrates a pattern 111 of one type of porosity that may be implemented -square openings 115C arranged in rows that are shifted from each other.

Pattern 111 may be applied to both a side view and a view from the bottom of dental implant 100, or may be applied on other two surfaces to build the three dimensional lattice with specified characteristics.

[0015] Dental implant 100 is produced layer by layer by laser sintering. The bone growth into body 110 enhances the stability of dental implant 100 and allows for close implantation of neighbouring implants.

[0016] Layer wise laser sintering allow generating continuous changes in the density of the three dimensional lattice through body 110 and in the transition to outer thread 95 and to inner thread 90. The border illustrated in Figure 1D between body 110 and outer thread 95 is for illustrative purposes, and may be replaced by continuous changes without any clear-cut border.

[0017] The three dimensional lattice may have an opening diameter between 0.1 and 1 millimeter, that may be selected according to implant size, intended use and surrounding tissue. Opening size may vary among different regions of body 100, in relation to expected surrounding tissue (bone type, gum) and its characteristic growth, in relation to the expected location of implant 100 in the jaw, and in respect to stmctural considerations or implant planning and the need to assure sufficient mechanical support to the inner and outer threads 90, 95.

[0018] Opening size may vary continuously within body 110, according to the afore mentioned criteria. Implant density may vary together with opening size to yield implants with a continuously variable density.

[0019] The form of the lattice openings may be chosen according to functional or stmctural criteria. Lattice openings may be round, square, hexagonal, or variable within body 110.

[0020] The distances between adjacent openings may be between 0.2 and 1.5 millimeter and may also vary within implant 100 according to implant size and intended use.

Changing distances between adjacent openings may be associated with the density variation of implant 100.

[0021] Dental implant 100 may be produced layer-wise by laser sintering. This production methods allows to tailor implants 100 according to implantation requirements (size, form and density distribution), as well as to mass produced specifically planned implant. The layer-wise production allows exact planning of lattice opening sizes and separation according to optimized models, adapted to bone growth parameters.

[0022] Layer-wise by laser sintering allows generating a very fine and a three dimensionally complex implant structure, which is difficult to achieve in other methods.

[0023] An additional advantage of producing implant 100 with three dimensional lattice body 110 by laser sintering is sparing implant material, as hollows in implant 100 are not cut out.

[0024] Bone growth factors may he associated with the produced implants 100 (e.g. implants may be soaked with bone growth factor prior to implantation) to enhance bone growth. The sizes and connectivity of lattice inner spaces may be selected to admit predefined amounts of specified solutions (e.g. bone growth factors, disinfectors, antibiotics, etc.).

[0025] The three dimensional lattice may have interconnected inner spaces, isolated inner spaces or a mix of the two, according to functional requirements from implant 100.

[0026] Implant size may vary between 0.6 to 2 millimeter in length. Different overall implant lengths and widths may determine the extent of body 110 and of the three dimensional lattice throughout body 110.

[0027] Figure 3 is a high level flowchart illustrating a method 150 of dental implants' production, according to some embodiments of the invention.

[0028] Method 150 comprises defining at least one three dimensional structure (e.g. a lattice) of a dental implant, to yield enhanced bone growth into the dental implant upon implantation (stage 155) and producing, simultaneously, by layer-wise laser sintering, a plurality of dental implants according to the at least one three dimensional structure (stage 160), wherein the enhanced bone growth into the body enhances implant stability and allows for close implantation of neighbouring implants.

[0029] The at least one three dimensional lattice structure may comprise a plurality of three dimensional lattice structures, each defined according to specified implantation requirements. Method 150 allow producing any number of any specially designed dental implant.

[0030] Thus producing the implants (stage 160) may comprise producing many implants of a single defined three dimensional lattice structures (stage 162), producing simultaneously different dental implants with individually tailored three dimensional lattice structures (stage 164) or a combination thereof.

[0031] Method 150 may further comprise deriving body structural parameters of dental implants according to implantation conditions (stage 152) and defining and producing the implants (stages 155, 160) accordingly.

[0032] Advantageously, the described implant 100 and method 200, allow generating a "bone implant" within the jaw, which both stabilizes implant 100, by reducing rejection and improper healing around implant 100, and allows placing multiple implants in closer proximity to each other, to better support the prostheses.

[0033] In relation to the prior art, the disclosed invention has the following novel and inventive features: the porous core structure and the three dimensional lattice core are arranged to accommodate bone ingrowth, and may be further individually designed and mass produced utilizing the layer-wise laser sintering method. The porous core may be designed to have a complex structure without increasing the production complexity, in sharp contrast to most prior art. Prior art disclosing laser sintering teaches producing surface features and not volume features of the implant, which lead to a qualitatively different effect.

[0034] In the above description, an embodiment is an example or implementation of the invention. The various appearances of "one embodiment", "an embodiment" or "some embodiments" do not necessarily all refer to the same embodiments.

[0035] Although various features of the invention may be described in the context of a single embodiment, the features may also be provided separately or in any suitable combination. Conversely, although the invention may be described herein in the context of separate embodiments for clarity, the invention may also be implemented in a single embodiment.

[0036] Furthermore, it is to be understood that the invention can be carried out or practiced in various ways and that the invention can be implemented in embodiments other than the ones outlined in the description above.

[0037] The invention is not limited to those diagrams or to the corresponding descriptions. For example, flow need not move through each illustrated box or state, or in exactly the same order as illustrated and described.

[0038] Meanings of technical and scientific terms used herein are to be commonly understood as by one of ordinary skill in the art to which the invention belongs, unless otherwise defined.

[0039] While the invention has been described with respect to a limited number of embodiments, these should not be constmed as limitations on the scope of the invention, hut rather as exemplifications of some of the preferred embodiments. Other possible variations, modifications, and applications are also within the scope of the invention.

Accordingly, the scope of the invention should not be limited by what has thus far been described, but by the appended claims and their legal equivalents.

Claims

CLAIMSWhat is claimed is: 1. A dental implant having a body comprising an inner thread for connecting an abutment thereto and an outer thread for connecting the dental implant to a jaw bone, characterized in that at least a part of the body is porous and is arranged to enhance bone growth into the body, and the dental implant is produced layer by layer by laser sintering, wherein the bone growth into the porous part of the body enhances implant stability and allows for close implantation of neighbouring implants.
2. The dental implant according to claim 1, wherein the porous part of the body comprises a three dimensional lattice.
3. The dental implant according to claim 2, wherein the three dimensional lattice has an opening diameter between 0.1 and 1 millimeter.
4. The dental implant according to any of claims 1 to 3, wherein the dental implant is produced layer-wise by laser sintering.
5. The dental implant according to any of claims 1 to 4, wherein the dental implant comprises titanium or titanium alloys.
6. The dental implant according to any of claims 1 to 5, wherein the body has a variable density according to required strength specifications, and wherein the variable density is achieved by accommodating the opening sizes and the distances between openings in the porous part of the body.
7. A method comprising: defining at least one three dimensional structure of a dental implant having a porous core, to yield enhanced hone growth into the dental implant upon implantation; and producing, simultaneously, by layer-wise laser sintering, a plurality of dental implants according to the at least one three dimensional structure, wherein the enhanced bone growth into the porous core enhances implant stability and allows for close implantation of neighbouring implants.
8. The method of claim 7, wherein the at least one three dimensional structure comprises at least one three dimensional lattice structure.
9. The method of claim 8, wherein the at least one three dimensional lattice structure comprises a plurality of three dimensional lattice structures, each defined according to specified implantation requirements.
10. The method according to any of claims 7 to 9, wherein the implants' production comprises at least one of: producing many implants of a single defined three dimensional structure; and producing simultaneously different dental implants with individually tailored three dimensional structures.
11. The method according to any of claims 7 to 10, further comprising deriving body structural parameters of dental implants according to implantation conditions, wherein implant definition and production are carried out according to the derived body structural parameters.