Patent Application
20210361393
The invention lies in the field of dental implant systems.
So-called single-part and so-called two-part implant systems belong to the dental implant systems.
In single-part dental implant systems, the actual dental implant—which is implanted into the jawbone and serves for anchoring a functional superstructure, for example a crown, a bridge or a prosthesis—has a structure that is accessible from coronally after the implantation and on which the attachment part can be fastened in a direct manner.
In two-part dental implants, apart from the actual implant (also called “anchoring part” or “screw” if it is provided with a thread), an abutment. which is envisaged for fastening to this actual implant, is necessary. Here, the anchoring part can be designed such that it is introduced in a manner in which it is approximately flush with the bone surface (as a so-called bone-level implant) or, coronally of the bone surface, it can be provided with a region that is often widened with respect to the enossal region, which is generally provided with a thread, the first-mentioned region sometimes being termed as a “tulip” and being envisaged to reach roughly up to the gum surface. Implants with such a transgingival region are called tissue-level implants. In two-part implant systems, the region (“post”) that projects out of the gums and which serves for fastening a superstructure, thus a crown, bridge, prosthesis or the like is formed by the abutment.
Amongst other things, a dental implant that consists of a thermoplastic or thixotropic material is known from WO 02/069 817. For anchoring, this material is pressed apically into the jawbone in a linear movement amid ultrasonic vibrations, by which means it is pressed in the flowable condition into the pores of the bone and is anchored there. Towards the coronal side, it has a structure, into which an artificial tooth can be screwed. With such a system, the orientation of the implant after implantation must be defined if the artificial tooth is shaped in an anatomically meaningful manner. WO 2004/017857 also teaches implants, amongst these dental implants, concerning which an anchoring in the bone is accomplished by way of liquefaction of thermoplastic or thixotropic material and the subsequent solidification in a condition, in which the bone tissue is interpenetrated. According to WO 2004/017857, additionally to thermoplastic or thixotropic material, the implant includes a part which forms a surface region of a non-liquefiable material, said region remaining free of liquefied material even after implantation. Similarly, WO 2005/079696 also teaches such implants which however are characterised in that bone tissue is removed apically by way of the linear movement on introduction. WO 2005/079696 also teaches embodiments, in which thermoplastic or thixotropic material is brought into a cavity and after liquefaction penetrates from this cavity through exits openings into the surrounding tissue. WO 2005/079696 teaches sealingly closing this cavity after implantation. Finally, according to WO 2011/054122, surgical implants are anchored by way of thermoplastic material, which in a flowable condition is pressed into the bone, wherein the surgical implant forms a sleeve with a longitudinal opening, into which a thermoplastic element is inserted and against whose distal end the element is pushed for the liquefaction.
The anchoring of the dental implants according to WO 02/069 817, WO 2004/017857 and WO 2005/079696 is advantageous since the dental implants are anchored in a stable manner directly after implantation and the anchoring can be loaded immediately, which entails very significant advantages for the patient. In contrast to this, the state of the art requires a protracted healing-in before the dental implants can be loaded. However, the mentioned systems all have the disadvantage that the fastening of the superstructure on their base cannot be achieved or not in a manner that is satisfactory for every situation. Moreover, there are problems with the acceptance of the primary anchoring amongst the implantologists who apply such systems, since for some, at least subjectively, the strength of the anchoring does not seem to be ensured in the manner that is taught by the documents.
It is an object of the invention to provide a dental implant and a dental implant system that overcome the disadvantages of the state of the art and which in particular permit an implantation with an immediate primary stability, without having to accept the disadvantages of the related state of the art.
According to a first aspect of the invention, a dental implant for implantation in the jawbone for the purpose of an indirect (via an abutment) or direct fastening of a superstructure is provided, said implant including:
The implant body further includes an outer thread. A structure for fastening an abutment or a superstructure is present towards the coronal side.
In many embodiments, the structure for fastening the abutment or the superstructure is at least partly present in the mentioned cavity and/or is penetrated by this cavity.
For the fastening of the abutment or superstructure, this can be attached to/stuck/placed onto the dental implant by way of a movement in the axial direction, and specifically in particular in a plurality of possible orientations, for example in a finite number of possible orientations or at an arbitrary rotation angle about an axis of the dental implant.
The combination of the afore explained additional anchoring by way of the thermoplastic material, which is pressed outwards through the at least one exit opening into the surrounding tissue, with a structure for fastening an abutment or a superstructure, the structure being at least partly present in the mentioned cavity and/or being penetrated by this cavity, can be advantageous independent of whether an outer thread is present or not. For example, the implant body can be structured such that it is introduced into the bone by way of hammering in and is held there by a press fit. The additional anchoring is subsequently effected as is described above.
Hence according to a second aspect of the invention, a dental implant is provided for the implantation in the jawbone for the purse of fastening a superstructure, the implant including:
Possibly, the following applies to both aspects: if the dental implant belongs to a two-part implant system, then in particular the cavity, in a coronal region, can form the structure for fastening the abutment, for example by way of a fastening post of the abutment projecting into the cavity in the put-together condition.
For the purpose of fastening the abutment, the cavity can include a structure that is undercut with respect to axial directions (an inner thread or a gluing groove, which runs at least partly in the peripheral direction also belong to this structure) and that permits a securing of the abutment with regard to pulling (tension) in axial directions, for example by way of an abutment screw, by way of an insert element, to which the abutment can be fixed and/or by way of cementing, wherein the undercut results in a combined material/positive connection.
Supplementarily or alternatively to this, the cavity coronally can include a support region, in which it has a coronally enlarging, in particular continuously enlarging cross section and by way of which forces can be transmitted in the axial direction from the superstructure, possibly via the abutment, into the actual implant. Such a support region can run, for example, conically or also in a slightly concavely arcuate manner in the axial longitudinal section.
Supplementarily or alternatively, the cavity can form a rotating-in (insert/insertion) geometry structure and/or rotational lock structure, i.e. in an axial depth region it is not designed in a rotationally symmetrical manner but has, for example, an n-fold rotation symmetry, wherein n is a natural number larger than 1, in particular a natural number between 2 and 10.
In these embodiments, the cavity for the thermoplastic and for a sonotrode, by way of which the thermoplastic is pressed apically and subjected to mechanical oscillation energy, and the recess known per se for the fastening and possibly rotational locking of the abutment as well as of the rotating-in (insert/insertion) tool form a common lumen.
The option of providing the fastening structure at least partly in the cavity and possibly providing it with the mentioned features, by way of the superstructure being provided directly with a fastening post, which engages into the cavity, also exists for single-part dental implant systems.
According to a second option, the single-part dental implant system is provided with a fastening post that projects coronally from the level of the gingiva and through which a coronal section of the mentioned cavity runs.
Altogether therefore, according to the first and/or second aspect, a system arises which in a combined manner has a series of important advantages:
In particular, the at least one exit opening can be arranged in the implant body relatively far apically, for example in the lower half or even in the lower third of the enossal region (the delimitation between the enossal region and the remaining regions is a characteristic of the implant). The thread at least over a region extends coronally of the exit opening and can even be restricted to regions coronally of the exit opening.
As already mentioned, in embodiments the dental implant system belongs to a two-part dental implant system, which moreover includes an abutment, i.e. an attachment part that interacts with the dental implant in order to be anchored on this and that includes a structure, for example a post, which permits the fastening of a superstructure. Two-part dental implant systems are particularly popular since they permit the actual dental implant to be able to heal in after implantation, without being subjected to loads on chewing. For this purpose, in the case of subgingival implants, the gums can be sutured over the implant after implantation; and transgingival implants are often dealt with provisorily by way of a cap. The inventive anchoring by way of a thermoplastic results in the implant being able to be loaded directly after implantation, i.e. the problems which in the state of the art lead to the preference for two-part implants do not exist for them. Despite this, the two-part design can also be advantageous with the procedure according to the invention, particularly since the abutment can be arranged at a selectable rotation angle and the aforementioned advantages concerning the absence of the necessity of a definition of the orientation of the implant therefore arise.
The following applies to single-part and two-part designs according to both aspects:
The cavity can run up to its apical end, for example essentially cylindrically, at least in an apical region.
The cavity is generally delimited by an abutting portion apically of the at least one exit opening, i.e. it is not axially continuous. The abutting portion can include an energy director structure, for example by way of it being raised towards the middle (with respect to radial directions) and for example being pointed or forming an edge.
If more than one exit opening is present—in many embodiments at least two exit openings are present—these can be arranged at the same height (have essentially the same axial position). If more than one exit opening is present, the exit opening are preferably arranged at different positions along the periphery and for example are uniformly distributed in the peripheral direction. In particular, two exit openings, which are arranged lying opposite one another, are present, and three or more exit openings that are distributed regularly in the peripheral direction are also an option.
The implant body can be ceramic or metallic. For example, it can be manufactured of a zirconium oxide ceramic, in particular of an yttrium-stabilised ceramic based on zirconium oxide. Alternatively, the implant body can also be of another material, for example of another ceramic, in particular of one based on aluminium oxide, or be of a metal, for example titanium or titanium alloy.
The enossal region of the implant body, in particular possibly the region provided with an outer thread can be roughened by way of an abrasive (material-removing) method and/or by way of a suitable coating. The healing-in of the bone is encouraged by way of this. In embodiments of the implant body as a ceramic implant body, the roughness can be present selectively only at locations of local prominences, for example on thread crests and not be present in the recesses therebetween, for example according to the teaching of WO 2011/054 119.
Further structures of a manner known per se, for example chip grooves or flutes, can be arranged at the outer side in the enossal region.
The invention also relates to a two-part dental implant system with an accordingly adapted abutment or a superstructure.
The invention moreover relates to an implantation set with a dental implant of the type described above, with an implant body and a thermoplastic element, for example according to the first and/or the second aspect. In particular, a guide sleeve can be present for the implantation, additionally to the implant body and the thermoplastic element, in order to guide the thermoplastic element on introduction and in particular to guide the sonotrode and to protect the implant body from the effects of the vibrating sonotrode.
Such a guide sleeve includes a guide lumen, which is continuous from coronal to apical (i.e. a continuous inner volume, in which and/or through which the thermoplastic element can be led). This lumen can have a cross section that is constant along the axis, i.e. be cylinder-symmetrical, even if the cavity has different regions with different cross sections. For example, it can have a circular cross section, i.e. be rotationally symmetrical about the axis. The guide lumen can be matched to a distal (apical on application) portion of the sonotrode in an exactly fitting manner, the portion being insertable into the guide sleeve, wherein the sonotrode has a slight underdimension. A flowing-back of the thermostatic material in the coronal direction towards the end of the liquefaction process can be prevented by way of such an essentially exactly fitting guidance.
The guide sleeve can optionally form a coronal widening (optionally but without the guide lumen also widening accordingly), in order to be supportable on the implant. The coronal widening can for example form a shoulder, which is supportable on a coronal end surface of the implant body, or it can be designed in a manner corresponding to an (optional) widening of the cavity, by which means the sleeve is supported in the same manner as later the abutment. Supplementarily or alternately, if the cavity of the implant includes a structure with is undercut with respect to axial directions for the purpose of fastening the abutment, the guide sleeve at the outer side can include a fastening portion that corresponds to this structure.
Additionally to the dental implant or to the dental implant system, an implantation set can include:
Such a sonotrode in particular can include a distal region whose shape is matched to the guide lumen of the guide sleeve, for example in an exactly fitting manner but with a slight under-dimension.
Such a sonotrode can be coupled directly onto a device for producing mechanical oscillations, or an intermediate part between such a device and the sonotrode can be used, for example for deflecting oscillations. Such an intermediate part is disclosed for example in WO 2007/101 362.
Embodiment examples of the invention are hereinafter explained in more detail by way of figures. In the figures, the same reference numerals indicate the same or analogous elements. There are shown in:
The implant body as a whole, with the exception of the thread recesses and the chip grooves, has an essentially cylindrical shape that merges apically into slightly tapering shape. The outer thread 11 has a non-constant thread depth and can be designed in a self-tapping manner.
The implant body 1 is manufactured for example of a zirconium oxide ceramic, in particular of an yttrium-stabilised ceramic based on zirconium oxide. Generally, the teaching, which is described here by way of embodiment examples, however also applies to implant bodies of another material, for example of another ceramic, in particular based on aluminium oxide, or of a metal, for example titanium or a titanium alloy.
A cavity 2, which is open to the coronal end, extends almost over the complete length of the implant and is delimited apically by an abutting portion 5 extends apically from the coronal end parallel to the axis 13. Two exit openings 4, which lie opposite one another, are formed radially outwards from the cavity 2 towards the outer surface (lateral surface). The abutting portion 5 is slighted pointed towards the middle, so that an energy director 7 whose function is yet explained hereinafter is formed.
Towards the coronal end, the cavity can include a widening 3, which in
The thermoplastic element 20 is designed in an essentially pin-like manner, for example cylindrically, with a cross section that is matched to the cavity and in particular to its apical region. The thermoplastic element can be designed in particular in a circularly cylindrical manner.
As is shown in
The interface between the sonotrode 22 and the thermoplastic 20 is continuously displaced apically during this process, by which means the coronal region of the cavity also remains essentially free of thermoplastic material and after the removal of the sonotrode can serve for the insertion of the fastening post of the abutment. Depending on the oscillation conditions and the length of the thermoplastic element 20, one can even envisage the coronal region of the cavity, for example in particular the region of the widening (and in the subsequent embodiments also in regions that serve for the anchoring apically of this) never coming into contact with the liquefied, thermoplastic material.
After a re-solidification subsequent to the energy input having been stopped, the liquefied shares 21 of the thermoplastic material, which are pressed into the bone, ensure an additional anchoring of the implant body 1 and thus of the complete implant in the bone tissue 10 and secure this in particular against being inadvertently screwed out or shaken out. This anchoring ensures an adequate primary stability during the healing-in phase.
According to a first possibility, the thermoplastic material of the thermoplastic element can be resorbable and thus be reabsorbed by the body after a few months when the implant is healed-in, whereupon the bone can grow through the exit openings 4 into the inside of the implant body 1 and therefore contribute further to the anchoring. Useable, resorbable polymers are, for example, polylactides, which are also commercially available for applications in surgery.
According to a second possibility, the thermoplastic element can be non-resorbable. The share of thermoplastic material with regard to the anchoring then remains the same. A useable, non-resorbable polymer is for example PMMA or a polyimide.
Apart from the fastening post 31, the abutment 30 represented in
A rotation-lock structure 32 can be formed on the fastening post 31. Such a rotation-lock structure 32 has an outer structure, which fits into the region of the implant which is not rotationally symmetrical, and fixes the rotation angle of the abutment relative to the jawbone. Very generally, the abutment in particular can be placed onto/attached to the implanted implant by way of a movement in the axial direction, without a substantial rotation.
In the example according to
The embodiment of
For this purpose, coronally of the enossal region, which is provided with an outer thread 11 and under certain circumstances is roughened and/or coated, it includes a transgingival region (line 19 shows the approximate level of the bone ridge), in which the implant projects slightly here.
In the represented embodiment, the abutment is moreover drawn with an angled, coronal post 34, and the abutment can be designed in a manner adapted to the position on the jaw and to the desired tooth position, independently of the design of the implant as a subgingival or transgingival implant and independently of the type of fastening.
In all embodiments, supplementarily or alternatively to a non-rotationally-symmetrical region (rotating-in (insertion) geometry region and/or rotation-lock region), the cavity 2 in the coronal region can optionally also include a support region, which has a diameter which increases slightly in the coronal direction and by way of which forces can be transmitted in the axial direction from the superstructure, possibly via the abutment, into the actual implant. Such a support region can, for example, be designed conically and, for example, lie coronally of the insert geometry region. Possible embodiments of regions of a coronally open cavity in the implant and its manners of functioning in the context of an interaction with a rotating-in (insert/insertion) tool and of the fastening of the abutment are described, for example, in the Swiss patent application 01 786/15, which is expressly incorporated herein by reference. The procedure of the present invention renders it possible to combine the functions of the recess, which is described therein, and generally of recesses for fastening an abutment or superstructure, with the function of the cavity for receiving the thermoplastic element and for introducing the sonotrode for the purpose of subjection to mechanical energy.
Such an insert element can be introduced with its apical end into the undercut insert element region by way of its apical end being able to be deformed on account of slots 44, which separate several segments 42 from one another. A through-opening 43 with an inner thread function, i.e. with an inner tread or at least with an inwardly projecting edge, which cooperates with an outer thread runs in the axial direction and extends centrally. A coronal head region 42 is not rotationally symmetrical but in its outer contour is adapted to the geometry of the non-rotationally-symmetrical region so that the insert element can be inserted in a manner secured against rotation. The segments can be fixed in the spread condition by way of screwing in an abutment screw (or also a corresponding screw of a rotating-in (insertion) tool), by which means the insert element and accordingly the screwed-in abutment screw or tool screw are secured against tension in the coronal direction on account of the undercut.
With embodiments for single part dental implant systems with an angulated post, the cavity can also merely extend through a part of the post.
Optionally, in the case of a single part dental implant system, the implantologist or dentist can fill the cavity from the coronal side with a suitable filler, for example with a cement, after the additional anchoring by way of the thermoplastic material and before the fastening of the superstructure.
A further feature of the implant according to
A structure for fastening the abutment, the structure being formed in the cavity 2 is represented once again in the shown example. The widening 3 here forms three regions: a support region 3.1, a rotation-lock region 3.2 with a structure that is not rotationally symmetrical about the axis, and an undercut region 3.3, here for fastening an insert element of the type described above.
All three regions are optional. The rotation-lock region with regard to this implant does not serve for the engagement of a rotating-in (insertion) tool, since such is not necessary at all. A rotation-lock region can be useful despite this, particularly if the rotation-lock effect of the pressing in the support region 3.1, between the implant and the abutment (or superstructure), is not sufficient or such a support region is not present; this is analogously the case with bonded (cemented) systems if the rotation-lock effect of the bonding connection is not sufficient.
By way of another embodiment of an implant body,
In the example of
The variant of the guide sleeve 70 according to
This also applies to the variant according to
With guide sleeves, which can be introduced into the cavity by way of a mere axial movement as is the case with the embodiments according to
| Number | Date | Country | Kind |
|---|---|---|---|
| 01000/16 | Jul 2016 | CH | national |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 15662578 | Jul 2017 | US |
| Child | 17392715 | US |
