DE102008019489A1 - Medicine product e.g. tooth-medical implant, for screwing into jaw bone of e.g. human body, has base body conically arranged to point within area of subsection and cylindrically arranged within area of another subsection - Google Patents

Abstract

The product e.g. tooth-medical implant (1), has a base body (2), at which a thread (4) is arranged. The thread has a tip at an end pointed in a screwing direction and accommodating unit for accommodation of a tool or prosthesis at another end. The thread is provided in a longitudinal extension within two sections (2.1, 2.2) of the base body, where the section (2.1) extends away from the tip and exhibits two subsections (2.1a, 2.1b). The base body is conically arranged to the point within the area of the subsection (2.1a) and is cylindrically arranged within the area of the subsection (2.1b).

Description

Technical area

The The present invention relates to a medical device, in particular an implant or a screw body with a thread, which is suitable to be screwed into a bone. Preferably, it is used in a jawbone to be inserted.

definitions

Under The term "medical device" is related to the invention described herein means an apparatus which includes a body on its outer wall includes at least one thread. The medical device is designed in such a way that it is for use in or on the human or animal body is suitable. In particular, this is here medical device described an implant that as an artificial, either resorbable or non-absorbable material that is permanent or at least for a longer period of time of the body should remain. Preferably, the medical device is a Dental implant. An alternative is also that the medical device a screw that is used to attach a plate or for fixing provided by bone.

State of the art

One Dental implant is a device that works by a suitable attachment to the bone is fixed. The implant is made usually from a main body, which is apical in extends to the bone, being on the cervical side of the implant a shaft is provided, on the one hand, the function of recording a prosthesis in the formation of a tooth, in particular a crown or prosthesis. On the other hand, the stem serves in his special training to insert the implant into the bone and fix it there.

Of the Body is provided with facilities for Ensure stable attachment within the bone.

In order to fix such an implant, the bone is first exposed in the area to be applied and then provided to create a bore, such that a preferably cylindrical cavity with a smooth surface is formed. Then there are two possibilities:
On the one hand, it is intended to cut a thread in the bone, which corresponds to the thread of the implant. Another possibility is not to further process the surface of the bore, but to select an implant that has a cutting thread.

The Service life of a prosthesis based on such an implant, is strongly dependent on the so-called osteointegration. This is a process caused by the growth of bone tissue structure is described in direct apposition of the implant. Osteointegration is also strong by the so-called primary stability of the implant in such a way that the denser the Implant is fixed within the hole, the better that is Bone growth.

Around now a reliable anchorage within the manufactured To achieve drilling implants are used with cutting threads. These are available in large numbers and design on the open market. Thus, it is known differently configured thread for to use such implants. These are implants with cone-shaped Threads and different conicities to one and the same Implant known. Some other implants are threaded, which are cylindrical. From known methods it is already known that good, long lasting results are achieved when osteointegrating between the bone and the implant with a tight profile and small thread pitches can take place.

In the WO 9725933 A (IMPLANT INOVATIONS, INC.) 13.01.1997 and the WO 9306786 A (RUSSO, GIANNI) 05.10.1992 implants are presented, which have threads that have a small conicity along the body. The flank base formed between the flanks of the thread is identical almost over the entire longitudinal extension of the base body.

In the WO 9725933 A (IMPLANT INOVATIONS, INC.) 13.01.1997 is proposed, in particular in conjunction with a hard bone, that the body should also have an asymmetric cross-section. This has the advantage of reducing the friction between the thread and the bone so as not to damage the bone trabeculae within the bone, which are essential for osteointegration.

Description of the invention

Technical problem

The problem with using cylindrical dental implants in cylindrical bores is that the threaded bore, which in most cases is created by a self-tapping tip of the implant, widened the cylindrical bore when the implant is screwed in. This occurs in particular in the inlet region of the bore (sometimes already by the drilling itself). This implies that there is little primary stability, especially in the cervical area. When conical implants are used, creating a conical hole usually causes the problem of heat build-up due to the cutting action and denting, which can lead to the destruction of the bone structure.

At it is obvious to make the threads such that these are cylindrical and a large thread profile with thin Have flanks. However, these thin threads have the disadvantage on that the few threads increased to Loads within the bore lead. In addition, you can due to the few threads no irregularities of the bone are compensated.

Consequently the object is to provide an implant that is for Solution at least one of the problems mentioned serves.

Solution of the task

The Solution of the problem is defined by claim 1.

Advantages of the invention

One significant advantage of erfindungsmässen implant exists in that this can be guided into a cylindrical bore is, so here's the advantage in the production and the gentle Processing of the bone lies and at the same time the implant is a cutting thread has on its apical facing side a few threads are designed for cutting, the rest exclusively are provided to achieve the primary strength.

The Thread on the body is designed so that it over the longitudinal extension of the body the same Slope. The slope is chosen such that adequate osteointegration is achieved as there is no fine thread structure having. This is a good enforcement of bone structures possible.

in the Contrary to the prior art has the thread shown here a cylindrical shape, although the main body a Conicity shows. This means that in the apical area of the implant, the flank depth is large, whereas in cervical Direction decreases.

advantageously, the flanks of the thread are designed so that the apical pointing flank is formed perpendicular to the longitudinal extent. This means that the flank surface is flat is. This achieves a high primary strength.

In cervical direction remains the design of the flank surface same, but the flank depth changes such that this is lower.

A advantageous embodiment provides that on the cervical End of the main body of the implant with a fine thread a smaller compared to the other thread thread pitch provided is. It serves to also increase the primary strength. The fine thread also provides a toothing to the already worked on bones, since just this area through the application of the drill and / or the implant inevitably no smooth surfaces can have more and possibly even in its dimensions is greater than the rest Part of the cylindrical bore.

The Formation of the implant in the described embodiment It also allows that area to accommodate a prosthesis or interaction with a tool for screwing of the implant sufficiently and in the dimensions larger as the main body can be designed as the to be transmitted Forces due to the strong cutting action of the first apically indicative Threads are sufficiently large.

Consequently The main advantage of the implant results from the fact that for example, soft bones, those with a small diameter is pre-drilled immediately after insertion of the implant the apical tip of the implant engages and due to the extreme fast tangential slope (formed by a shell, which rests against the flank tips of the thread in contrast to tangential slope of the body) a spin the thread is prevented.

Already from the time the bone is at the core diameter of the bone Diameter of the thread of the second section is widened, this diameter remains over the longitudinal extent of the implant identical, so that from the main body seen a cylindrical shape is present. This avoids that no further bone compaction takes place in this area.

The sees special embodiment of the second portion of the implant Above, tolerances, especially when drilling on the cervical side arise, compensate.

Therefore, the second portion of the implant is plug-shaped and larger in diameter than the rest of the part. It is also featured see that in this second section, although a thread with the same pitch is provided, as it is already known from the first section, but in double (double thread, such that the distance between the one edge tip to the adjacent edge of the tip is bisected) in particular in this area, to achieve the desired high primary stability.

A particular embodiment of the invention therefore provides over the entire longitudinal extent of the implant, the to use the same pitch of the respective sections of the thread, However, to differentiate in flank depth and edge distance.

The implant according to the invention is not for use limited in the dental field. It also forms the basis for a screw that is also in the bone area is used and it is desired that a sufficient Stability or strength should be present.

Further advantageous embodiments will become apparent from the following description and the claims. This shows representatively for the inventive medical device and the Thread a dental implant, the thread of the invention having.

drawings

It demonstrate:

1 a perspective view of the inventive implant;

2 a side view of the implant;

3 a section through the implant along a line III-III according to 2 ;

4 a section through the implant along a line IV-IV according to 2 ,

Description of an embodiment

The description of an embodiment relates to the representation in the 1 to 4 ,

This is an implant 1 shown, which is essentially a basic body 2 and a cervical shaft 3 includes. The shaft 3 is designed as a functional element (means) and serves on the one hand, with a corresponding tool, such as a screwdriver, cooperate to screw the implant into a bone. Furthermore, it serves for example to receive a prosthesis.

The main body 2 is in this illustrated embodiment in two sections, namely a first section 2.1 and another section 2.2 divided and threaded 4 Mistake. The first section is on the apical side of the implant 1 whereas the other section 2.2 on the cervical side of the body 2 Direction of the shaft 3 extends.

The main body 2 itself extends in the apical direction initially cylindrical, with this section extends conically from a defined point.

The thread 4 is defined by thread flanks 4.1 , the distance 6 from a thread flank 5 to the adjacent thread flank 5 as well as the flank depth 7 extending from a flank tip 8th to the flank bottom 9 measured. The thread 4 in the area of the first section 2.1 is arranged, has the same slope S1 over the entire area. A hull H1, which over the flank tips 8th of the first section 2.1 is laid, has a pointing to the apical side parabola.

Additionally, in the first section 2.1 recesses 10 provided, which have the property of the first threads of the thread 4.1 of the first section 2.1 take up removed material and transport it in the cervical direction.

The thread flank 5 is preferably designed such that its two flank surfaces, namely the first flank surface 12.1 and the other flank surface 12.2 are not symmetrical. The first flank surface 12.1 , which points to the apical side, is flat and preferably extends perpendicular to the longitudinal extent of the body 2 whereas the more flank surface 12.2 forms an angle α with the flank tip.

The second section 2.2 has another thread 4.2 on, in contrast to the thread 4.1 of the first section 2.1 has a lower slope S2. The longitudinal extent of this section 2.2 is compared to the first section 2.1 also much shorter. A special embodiment of the implant 1 shows that the slope S1 of the first section 2.1 the slope S2 of the second section 2.2 equivalent. Another preferred embodiment shown in the drawings shows that the further section 2.2 has a double thread. This is characterized by the fact that the distance between the flank tips 8th this further section 2.2 opposite the first section 2.1 is halved.

Functionality:

To the different function of the thread 4 , which is divided into its corresponding sections (first section 2.1 , second part 2.2 ), the implantation of an implant is explained below.

Depending on the bone in which the implant 1 is introduced, is pre-drilled with an appropriate diameter.

The implant according to the invention 1 is introduced with its apical tip in the direction of insertion E in the pre-drilled bore, to the point where further insertion is no longer possible. This is the time at which the first thread of the first section 2.1 attacks. The first paragraph 2.1 is divided into two subsections, namely a first subsection 2.1a and a second subsection 2.1b , The first subsection 2.1a is formed so that the thread 4 (in 3 through a hull H1, which over the flank tips 8th is shown) has a steeper compared tangential slope than the main body 2 , which is preferably conical in shape and in 3 is shown by a sheath H2 in cross section.

This particular embodiment now leads to the fact that immediately after insertion of the implant 1 into the hole the thread 4 apical begins to grip. By further screwing in is prevented due to this particular embodiment that when inserting the bone compaction generated by the screwing, a spinning of the implant 1 is prevented.

Will the implant 1 now further screwed, the implant reaches the point, namely the second subsection 2.1b , In this area, the bone becomes the core diameter of this threaded section 4.1 extended. Because of that, the main body 2 In these areas, its size is no longer greater, the bone compaction is then adjusted at a certain point, so that with the same thread 4 this alone achieves a higher primary stability.

By further screwing is now the second section 2.2 of the implant 1 reached. This area is designed such that it has a double thread 4.2 which also shows a slope S2, that in the first section 2.1 provided slope S1 corresponds. As a rule, this is exactly this area, because this one of the implant 1 has already been passed through, but also when drilling the desired diameter is designed by appropriate tilting further than necessary. Therefore, the implant is 1 in terms of its basic body 2 in diameter to a larger designed to just cover these resulting processing tolerances and on the other to increase the primary stability. In addition, however, a double thread is provided with which also a high primary stability can be additionally achieved.

The inventive implant is characterized by a simple Implantation in a cylindrical bore made with a implanted lower torque compared to the prior art is. In addition, in comparison to the prior art, a high primary strength where. Conventional tools for making the hole as well for implantation can be readily used. The design of the implant or the inventive Medical device combines all advantages of implants and screws for screwing into bone, which is exclusively a conical or cylindrical body with the corresponding thread have the same flank depth.

The Advantages of the cylindrical design are high safety, no damage of the bone, are combined with the advantages of the conical design (high bone density, high primary stability).

The Invention is not limited to implants for the tooth area. Rather, the claim is based on the inventive Thread attached to medical devices, such as implants, screws or The same is arranged for screwing in bone.

1

implant

2

body

2.1

first section

2.1a

subsection

2.1b

subsection

2.2

Another section

3

shaft

4

thread

4.1

thread

4.2

additional thread

5

thread flank

6

distance

7

edge depth

8th

edge tip

9

edge basic

10

recess

12.1

first flank surface

12.2

Further flank surface

S1

pitch

S2

pitch

H1

shell

H2

shell

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - WO 9725933 A [0008, 0009]
• - WO 9306786 A [0008]

Claims (14)

Medical device for screwing into a bone, comprising a base body on which a thread is arranged, which has a tip at its end in the screwing-in direction and at the other end a means for receiving a tool or prosthesis, characterized in that the medical device in Longitudinal extension within a first section ( 2.1 ) and another section ( 2.2 ) the thread ( 4 ), and the first section ( 2.1 ) extends from the top and two subsections ( 2.1a . 2.1b ), wherein in the region of the first subsection ( 2.1a ) the basic body ( 2 ) conically towards the tip and in the region of the second subsection ( 2.1b ) the basic body ( 2 ) is cylindrical. Medical device according to claim 1, characterized in that the flank depth ( 7 ) in the area of the first subsection ( 2.1a ) from the top to the further subsection ( 2.1b ) decreases. Medical device according to claim 1 or 2, characterized in that the flank depth ( 7 ) in the area of the second subsection ( 2.1b ) is constant. Medical device according to one of the preceding claims, characterized in that a sheath (H1) placed around the flank tip (H1) 8th ) of the thread ( 4 ) within the first section ( 2.1 ), has a substantially cylindrical shape. Medical device according to one of the preceding claims, characterized in that the thread ( 4 ) over sections ( 2.1 . 2.2 ) of the basic body ( 2 ) has the same slope (S1, S2). Medical device according to one of the preceding claims, characterized in that the flank depth ( 7 ) within the further section ( 2.2 ) continues to decrease towards the other end. Medical device according to one of the preceding claims, characterized in that in the region of the first section ( 2.1 ) a shell (H1) around the flank tips ( 8th ), has a greater tangential slope than a shell (H2), which fits to the outer contour of the main body ( 2 ) is to lay. Medical device according to one of the preceding claims, characterized in that in the region of the first section ( 2.1 ) one in the longitudinal extension of the implant ( 1 ) formed recess ( 10 ) is provided. Medical device according to one of the preceding claims, characterized in that in the region of the second section ( 2.2 ) a formed in the longitudinal extent of the implant recess ( 10 ) is provided. Medical device according to at least one of the preceding claims, characterized in that the thread ( 4 ) two flank surfaces ( 12.1 . 12.2 ), wherein the first flank surface ( 12.1 ) perpendicular to the longitudinal extent of the basic body ( 2 ) is trained. Medical device according to claim 10, characterized in that the further flank surface ( 12.2 ) with the first flank surface ( 12.1 ) includes an angle α. Medical device according to at least one of the preceding claims, characterized in that the second section ( 2.2 ) a thread ( 4.2 ) with the slope (S2), said slope (S2) of the pitch (S1) of the thread ( 4.1 ) of the first section ( 2.1 ) corresponds. Medical device according to claim 12, characterized in that the thread ( 4.2 ) of the second section ( 2.2 ) is a double thread. Medical device according to at least one of the preceding claims, characterized in that the diameter of the basic body ( 2 ) in the area of the second section ( 2.2 ) increases in the direction of insertion (E) pioneering side with increasing distance from the tip.