DE19713305A1 - Resorbable obturator for bone regeneration, requiring less preparation than titanium type - Google Patents

Abstract

Obturator (1) comprises dimensionally-stable resorbable material for sealing an internal chamber (4). It has a fixing part (3) for fixing in a cavity (5) with standardised dimensions, formed in a bone (6), and a cover (2) for covering the hole on the side away from the bone.

Description

The invention relates to an obturator, which is in essence chen consists of resorbable material. Such an obturator can be used, for example, to treat bone wounds will. Special applications are the treatment of bones bleeding from alveoli and from defects in the ZMK area, like them occur, for example, after tooth extractions. After such Tooth extractions remain in a wound cavity, the healing of which in usually with a loss of bone and a defect situation in the alveolar ridge. Conventional surgery measures, such as coagulation within the after Tooth extraction in the bone cavity left behind leave it to that the jaw mucosa faster in this free space proliferates into it when new bones are reproduced from below becomes.  

It is therefore known to use membranes to cover such wound cavities to use to give the bone the opportunity to wound fill the cavity so that there is no defect situation in the alveolar ridge remains. In addition to non-degradable membranes for this Also resorbable membranes for the closure of alveoli and the like.

A disadvantage of the use of absorbable membranes is that they have no primary retention in the surrounding tissue. she must with fixation aids, such as nails or Screws to be fixed in situ. The membranes also have low dimensional stability. It is often used for Wound cavity to be kept free through a colla membrane no longer suffices before the ingrowth of other tissue protected. Furthermore, no one is really you ter connection between the known membranes and the bone, in which the wound cavity is located. The membranes are as the only measure, therefore, often inadequate to a bone to stop bleeding. In addition, the deformability of Membranes also adversely affect reparative mechanisms that require a consistent resetting of the bone fragments, what is well known from bone fracture healing. Last one is the use of membranes with a complex Preparation technique with exposure of the surrounding bone connected to place the membranes correctly and securely cover soft tissue.

It is also a regenerative-augmentative therapy of the alve known as Guided Bone Regeneration (GBR) a degenerated alveolar bone using the space holder effect of a membrane is rebuilt. Here too the disadvantages of membranes described above occur.

It is used to improve the dimensional stability of membranes known to embed titanium support grids in the membranes. As a result, the disadvantages of membranes described above but only partially eliminated. In particular, the preparative  Effort increased even further, because of a titanium lattice stabilized membrane, for example, difficult to in curved bone is adaptable in several respects.

From Clin-Oral-Implants-Res 1995 Jun; 6 (2): 67-72 is a Obturator made of dimensionally stable titanium known to lock an interior above a rabbit skull roof and below the associated periosteum was used to make a Bone growth into this protected interior trigger.

The invention has for its object a resorbable To show obturator with little preparative effort can be used, and the one space in which a bone regeneration should take place, safe from the overgrowth of others Tissue protects.

This object is achieved by an obturator in the essentially made of dimensionally stable resorbable material, which is provided for locking an interior, the Obturator an anchoring part for anchoring in a standardized dimensions in a cavity and a cover part for covering the interior in a bone facing away. The new obturator is also in the In contrast to a membrane reinforced by a titanium grid dimensionally stable. The obturator is used to lock an interior Raums, so that the desired bone rain in this interior ration can take place. To seal this interior tightly the obturator is not adapted to the bone, however it becomes a cavity with standardized dimensions in the bones introduced and in so far as an adjustment of the bone to the Obturator made. The anchorage is in this cavity part of the obturator anchored. By anchoring the Anchoring part is also a lateral seal of the interior. In the direction away from the bone the seal through the cover of the obturator. The preparation expenditure on using the new obturator can affect  Introduction of the standardized cavity into the bone and that Anchoring the anchoring part of the obturator in the cavity restrict.

In one piece formed with the cover Anchoring part can already with these measures alone Bleeding from the bones, such as occurs after tooth extraction, being stopped. At the same time, there is no risk that Jaw mucosa proliferates in the wound cavity, which after the Tooth extraction in the bone remains. Rather, here a bone regeneration take place in the long term too the obturator is broken down and replaced with bone. By the Use of the obturator will be sewing up the jaw mucosa and other wound care measures after tooth extraction in generally superfluous, since for example no food either leftovers from the oral cavity into those remaining in the bone Free space can penetrate.

When bone regeneration occurs, for example, through attachment of bone chips or the like is to be particularly promoted it is advantageous if the cover part and the anchoring part are separate components. So it is possible to anchor first anchoring part in the standardized cavity. Subsequently the interior of the obturator in the desired manner prepared, for example filled with bone chips, and first finally the cover part is ver with the anchoring part bound.

It is advantageous if the cover part with the sealing Anchoring part is connectable to, for example, bleeding to stop. To form a particularly sealing Connection between the cover part and the anchoring part, the cover can be screwed into the anchoring part or be snapped into place.

The anchoring part preferably has a closed umlau opening wall. The standardized cavity for anchoring the  Anchoring part can be closed accordingly circumferential channel in the bone that is the area of the surrounding the desired bone regeneration. The standardized However, the cavity does not necessarily have to be channel-shaped. she can for example also have the shape of a coherent hole without remaining core or from individual Channel sections exist.

An anchoring part with a closed peripheral wall has preferably a basic shape like a hollow cylinder. Through the Rotational symmetry of this basic form is a screwing in Anchoring part around the cylinder axis in the standardized cavity possible.

Even if the anchoring part is not a hollow cylinder-like reason has shape, the anchoring part is preferably in one piece designed to seal the interior side tightly to reach the obturator. But it is also possible that Form anchoring part in several parts. This is particularly useful especially with elongated interiors of the obturator, inside whose bone regeneration is to be made possible.

The anchoring part usually has retention elements its outward surface and / or on its inside surface. Retention elements on the after inside surface of the anchoring part are only then makes sense if the standardized bone Cavity a core of bone in the interior of the obturator leaves behind where the retention elements can attack.

The retention elements can be barbs and the like. act. However, an external thread on the outward and / or an internal thread on the inside surface of the anchoring part. To the The anchoring part is then anchored with the thread in the standardized cavity screwed into the bone.  

To facilitate this screwing in, the anchoring part have an abutment for attacking a tool. A such abutment is also advantageous on the cover, if this, for example, screwed into the anchoring part or if it is screwed in one piece The anchoring part is formed.

While the anchoring part is rotationally symmetrical Basic form is the insertion into the standardized cavity in the bone facilitated and therefore preferred, the cover part in a preferred embodiment of the obturator Bone-adapted, possibly asymmetrical basic shape point. This prevents the obturator in unphysiolo survives over the bones.

The cover part can have a window to also after the Close the obturator's interior inspect or administer medication inside to make. The window can be an open and closable window, but also around one of a membrane act covered opening in the cover part, the Membrane is pierced with a cannula and after the Removing the cannula closes again.

The obturator can essentially consist of an absorbable inorganic material, especially tricalcium phosphate ceramic, or a resorbable organic material, in particular Polylactide. These materials indicate when more suitable Composition and manufacture of sufficient dimensional stability on to the anchoring part of the obturator in the standardized Anchor cavity and around the interior of the obturator despite the resorbability of the material over a sufficiently long period Complete periods for the desired bone regeneration. It is not necessary that the obturator Anchoring part and the cover part made of the same material consist.  

Tricalcium phosphate ceramic is a fully synthetic one phase-pure β-tricalcium phosphate that is biodegradable. Thanks to the exact stoichiometric composition and physiology The pH value of β-tricalcium phosphate is excellent Biocompatibility and defined absorption properties. The Resorption occurs simultaneously with new bone formation and becomes positively influenced by the interconnecting porosity. β-tricalcium phosphate is primarily for resorbable implants known and approved according to the Medical Devices Act.

In addition to polylactides, polyglycolides and polydionaxones are also available synthetic polymers of aliphatic polyester suitable organic absorbable materials for the obturator. This Synthetic polymers are biodegradable in a biological environment. They are already used to manufacture implantable splints, Plates, screws and wires, as well as sutures and membranes used. Approval under the Medical Devices Act is pending in front.

Although the obturator is preferably made entirely of absorbable Material, the obturator or part of the Obturators a non-absorbable scaffold for one resorbable matrix, especially of calcium hydroxyapatite, Have alumina or titanium. This scaffold is preferably lattice-shaped to deal with the newly formed To connect bones tightly. Calcium hydroxyapatite and aluminum Oxides are known in medicine and for bone augmentation or ceramic that is widely used for endosseous implantology Materials. They are not biodegradable, they combine but with the regenerating bone. Educated from them Support structures for a resorbable matrix can change the shape of bars, bars, rings or meshes.

Parts of the anchoring part of the obturator can also be made resorbable material may be lattice-shaped in order to Bone growth into the interior of the obturator accelerate. But this is only for parts of the obturator  sensible that completely in the standardized cavity in the bone be sunk. Because these parts or areas of the obturator rarely be certain from the outset, it is also possible to to train the corresponding parts first and after the Inserting the anchoring part into the cavity, for example by drilling through holes in the complete Areas of the anchor located within the cavity partly to bring.

The dimensions of the new resorbable obturator depend on the area of the bone to be treated. The new obturator is of course not on the closure of wound cavities limited how they remain after tooth extraction. So the new obturator can also be used, for example to prevent the formation of pelvic bones, for example Bones for the removal of bone chips for a self-transplant to promote tation. Depending on the area of application are conceivable Obturator diameter from under 3 to over 50 mm, heights from under 2 to over 20 mm and wall thicknesses under 0.025 to over 1 mm. For the closure of wound cavities that look like tooth extract ions are obturators with a diameter of 3 to 10 mm and a maximum height of 10 mm is also suitable. The wall thickness must be used due to the dimensional stability of the Material should not be particularly large, so that the standardized cavity not an unnecessarily large one to accommodate the anchoring part Represents bone defect.

The obturator is preferably a cutting rotating one or oscillating tool is assigned, its dimensions correspond to the cavity with the standardized dimensions. A oscillating tool has the advantage that the cavity does not have to have a uniform depth over its circumference.

The obturator can also have a cutting rotating or oscillating tool, the dimensions of which are only a part of the Cavity with the standardized dimensions, and a Template for attaching the tool when inserting the  Cavity in the bones. This embodiment is particularly good for cavities without rotational symmetry Cross section advantageous.

The invention is based on various Embodiments explained and described in more detail. Here shows:

Fig. 1 a first embodiment of the introduced in a bone obturator in longitudinal section;

Fig. 2 is a perspective longitudinal sectional view of the obturator of FIG. 1 without the bone,

Fig. 3 is a Fig. 2 corresponding view of a second embodiment of the obturator with other retention elements.

Fig. 4 is a FIGS. 2 and 3 showing a further embodiment of the obturator with yet other retention elements,

Fig. 5 shows a modification of the obturator of FIG. 4 ratem with sepa cover,

Fig. 6 shows a modification of the obturator of FIG. 5 with a window in the cover,

Fig. 7 shows a modification of the obturator of FIG. 5 with a domed cover,

Fig. 8 shows a modification of the obturator shown in FIGS. 1 and 2 with a separate cover,

Fig. 9 shows a modification of the obturator of FIG. 8 with ecki gem cross-section,

Fig. 10 is a perspective view of a standardized Cavität for anchoring an obturator with a particularly high cross-sectional area,

Fig. 11 an obturator inserted into a jawbone in a further embodiment in longitudinal section;

Fig. 12 is a perspective view of an obturator with a multi-part anchoring part in longitudinal section and

Fig. 13 is a cross section through the anchoring part of the obturator of Fig. 12.

The obturator 1 shown in FIGS . 1 and 2 has an anchoring part 3 and a cover part 2 . The anchoring part 3 and the cover part 2 are integrally formed from a resorbable material. The material is tricalcium phosphate ceramic. The obturator 1 has an interior 4 . The interior 4 is closed off by the obturator 1 when, as shown in FIG. 1, it is introduced into a cavity 5 in a bone 6 . The cavity 5 has the shape of a hollow cylinder with standardized dimensions. The obturator 1 has a hollow cylindrical basic shape, barbs 7 being molded onto the anchoring part 3 as retention elements. The barbs 7 engage in the wall 8 of the cavity 5 and hold back the anchoring part 3 in the cavity 5 . Through the anchoring part 3 , the interior 4 is closed abge laterally. The cover part 2 closes the interior 4 in the direction facing away from the bone 6 . The obturator 1 thus prevents non-bone tissue from growing into the interior 4 . Rather, the bone 6 is able to regenerate while filling the interior 4 and when the resorbable obturator 1 is removed, also the remaining cavity 5 occupied by it. Anchoring the obturator 1 also stops any bleeding in the area of the cavity 5 . A core 9 made of bone has remained in the cavity 5 according to FIG. 1. The core 9 is not used here for anchoring the anchoring element 3 . However, it would be unnecessary to also remove the core 9 when inserting the cavity 5 into the bone 6 with standardized dimensions, since the obturator 1 should make it possible to fill the interior with bone. As has already been stated, the cavity 5 according to FIG. 1 is hollow-cylindrical and can therefore be easily inserted into the bone 6 using a rotating tool.

The obturator 1 according to FIG. 3 is also matched to such a hollow cylindrical or cylindrical cavity. In contrast to the obturator according to FIGS. 1 and 2, an external thread 10 is formed on the outside of the anchoring part 3 as a retention element. The external thread 10 can be used to screw the obturator 1 into a cavity, the external thread 10 engaging in the wall of the cavity.

FIG. 4 shows an obturator 1 which , in a modification of FIG. 2, has an anchoring part 3 with an internal thread 11 instead of an external thread. In order to anchor the obturator 1 according to FIG. 4 in a cavity, a core must remain in the cavity, in the surface of which the internal thread 11 can engage in order to retain the obturator 1 .

An internal thread 11 on the inside of the anchoring part 3 of the obturator 1 can not only be used to anchor the anchoring part 3 in a cavity. FIG. 5 shows how the internal thread 11 can also be used to connect the cover part 2 of the obturator 1 to the anchoring part 3 if the anchoring part 3 and the cover part 2 are designed as separate components. If the external thread 12 of the cover part 2 engaging in the internal thread 11 is excessive or widens conically, a seal can be achieved in a simple manner between the anchoring part 3 and the cover part 2 .

In addition to the obturator 1 according to FIG. 5, the obturator 1 according to FIG. 6 has a window 13 in the cover part 2 . The window 13 is formed by a screw-in part 14 which engages with an external thread 15 in a threaded bore 16 in the cover part and closes this threaded bore. The A screw part 14 is removable with a tool. For this purpose, an abutment 17 for the tool is formed on the screw-in part 14 . The screw-in part 14 can be removed, for example, in order to inspect the interior 4 or to add antibiotics or other substances into the interior 4 . An abutment, not shown here, can also be provided to screw the cover part 2 into the anchoring part 3 with the aid of a tool. The anchoring part 3 according to FIGS. 5 and 6 can be designed as an excessively long tube which is cut to length for the respective application. The cutting can be done before anchoring the anchoring part in the cavity with the standardized dimensions or only after anchoring.

The obturator 1 according to FIG. 7 differs only with regard to the cover part 2 from FIGS. 5 and 6. The cover part 2 is here curved upwards in order to enable a better adaptation of the obturator 1 to the contour of the bone in which the Obturator 1 is to be anchored. Despite the thread play 18 shown in FIG. 7 between the internal thread 11 of the anchoring part 3 and the external thread 12 of the cover part 2 , a sealed connection of the anchoring part 3 and the cover part 2 is preferably provided in the obturator 1 .

Such a sealing connection can also be achieved by snapping the cover part 2 onto the anchoring part 3 . Such an embodiment of the obturator 1 is shown in FIG. 8. The anchoring part 3 according to FIG. 8 corresponds to the embodiment of the obturator 1 according to FIGS. 1 and 2. However, here the anchoring part 3 and the cover part 2 form two separate components. To connect the anchoring part 3 to the cover part 2 , the anchoring part 3 has an annular groove 18 and the cover part 2 has an annular bead 19 . The bead 19 is designed such that it can snap into the groove 18, a first sealing plane being formed in the region of the groove and the bead and a second sealing plane being formed below a collar 20 of the cover part 2 and the upper edge 21 of the anchoring part 3 .

In the embodiments of the obturator 1 according to FIGS. 1 to 8, the anchoring part 3 has a hollow cylindrical basic shape, and the cover part 2 is essentially circular. These dimensions are matched to cylindrical standard cavities for anchoring the obturator 1 . Fig. 9 shows an obturator 1, which is tuned to a rectangular limited Cavität. Otherwise, the embodiment of the obturator 1 according to FIG. 9 corresponds to that according to FIG. 8. Also according to FIG. 9, the wall 22 of the anchoring part 3 is circumferential, so that it delimits the interior 4 on all sides. A standardized cavity coordinated on the obturator 1 according to FIG. 9 cannot be introduced into a bone in one operation with a rotating tool. However, it is easily possible to introduce four perpendicular slots into a bone with a template and a separating disc, which together form exactly the cavity required for anchoring the obturator 1 according to FIG. 9.

Fig. 10 shows a cavity 5 which differs from a cylindrical shape in other respects. So in the bone 6 here three cylindrical, but partially overlapping holes are introduced, which together form the cavity 5 . By the location and distance of the individual holes and their diameter, the dimensions of the cavity 5 are standardized, so that a corresponding anchoring part can be anchored on the wall 8 of the cavity 5 without additional preparation measures besides the introduction of the individual holes for the cavity 5 .

Fig. 11 shows an anchored to a bone 6 obturator 1, which is designed especially for use by dental extractions of a lower jaw. The obturator 1 is anchored in an annular cavity 5 , which was introduced into the bone 6 in a ring shape around a wound cavity (not shown). The obturator 1 thus stops bleeding from the wound cavity by completely closing it. At the same time, the obturator 1 prevents the overgrowth of jaw mucosa in the wound cavity. Instead, the bone 6 is given the possibility of filling the interior 4 of the obturator 1 by regeneration. The obturator 1 has an asymmetrical structure to match the topography of the bone 6 . Openings 23 are also arranged asymmetrically in the anchoring part 3 of the obturator 1 . The openings 23 are all located within the cavity 5 and are intended to accelerate the regeneration of the bone in the interior 4 . Since the coverage of the cavity 5 and the obturator 2 is subject to certain variations, it does not necessarily make sense to provide the openings 23 in a fixed arrangement in the anchoring part 3 . Rather, it is preferred that the perforations 3 during implantation of the obturator 1 in more detail adaptation to the prevailing If units are introduced into the anchoring part. 3 In the case of an obturator 1 with a separate cover part, this is also possible after anchoring the anchoring part 3 in the cavity 5 in the bone 6 by placing individual bores in the anchoring part 3 .

In the obturator 1 illustrated in FIGS. 1 and 2 is not only the cover part 2 is provided as a separate component in addition to the anchor portion 3, and the anchoring member 3 is formed in multiple pieces out. The anchoring part 3 has two parts with a hollow cylindrical basic shape, each of which corresponds to the anchoring part according to FIG. 8. In these two components, the cover part 2 is snapped into place with cylindrical projections 24 , which is essentially plate-shaped in the planar expansion of the collar 20 according to FIG. 8. The cover part 2 thus not only closes the interior spaces 4 within the components with a hollow cylindrical basic shape of the anchoring part, but also delimits a further part of the interior space 4 between these components. In the area of the anchoring element 3 , this part of the interior 4 is laterally delimited by a side wall 25 , which is engaged with projections 26 in recesses 27 in the two components with a hollow cylindrical basic shape. On the side opposite the side wall 25 , the interior 4 is closed abge by areas of the bone. The obturator 1 according to FIGS. 12 and 13 can be used, for example, if a jaw ridge is to be built up in a targeted manner after two tooth extractions for anchoring an implant. For this purpose, for example, bone chips can be filled into the interior 4 before it is closed with the cover part 2 .

Reference list

1

Obturator

2nd

Cover part

3rd

Anchoring part

4th

inner space

5

Cavity

6

bone

7

Barbs

8th

Wall

9

core

10th

External thread

11

inner thread

12th

External thread

13

window

14

Screw-in part

15

External thread

16

Tapped hole

17th

Abutment

18th

Groove

19th

bead

20th

Federation

21

Top edge

22

Wall

23

Breakthrough

24th

head Start

25th

Side wall

26

head Start

27

Recess

Claims (17)

1. Obturator essentially made of resorbable material, characterized in that the obturator ( 1 ) is made of dimensionally stable resorbable material and is provided for closing off an interior ( 4 ) and that the obturator ( 1 ) has an anchoring part ( 3 ) for anchoring in a has standardized dimensions in a bone ( 6 ) cavity ( 5 ) and a cover ( 2 ) for covering the interior ( 4 ) in a direction facing away from the bone ( 6 ). 2. Obturator according to claim 1, characterized in that the anchoring part ( 3 ) is formed in one piece with the cover part ( 2 ). 3. Obturator according to claim 1, characterized in that the cover part ( 2 ) and the anchoring part ( 3 ) are separate components. 4. Obturator according to claim 3, characterized in that the cover part ( 2 ) is sealingly connected to the anchoring part ( 3 ). 5. Obturator according to claim 3 or 4, characterized in that the cover part ( 2 ) in the anchoring part ( 3 ) can be screwed or locked. 6. Obturator according to one of claims 1 to 5, characterized in that the anchoring part ( 3 ) has a closed umlau fende wall ( 22 ). 7. Obturator according to claim 6, characterized in that the anchoring part ( 3 ) has a hollow cylindrical basic shape. 8. Obturator according to one of claims 1 to 7, characterized in that the anchoring part ( 3 ) is integrally formed. 9. Obturator according to one of claims 1 to 8, characterized in that the anchoring part ( 3 ) has retention elements on its outwardly facing surface and / or on its inwardly facing surface. 10. Obturator according to claim 9, this referred back to claim 7, characterized in that the anchoring part has an external thread ( 10 ) on its outward surface and / or an internal thread ( 11 ) on its inward surface. 11. Obturator according to one of claims 1 to 10, characterized in that the cover part ( 2 ) and / or the anchoring part ( 3 ) have an abutment for the attack of a tool. 12. Obturator according to one of claims 1 to 11, characterized in that the cover part ( 2 ) has an asymmetrical basic shape adapted to the bone ( 6 ). 13. Obturator according to one of claims 1 to 12, characterized in that the cover part ( 2 ) has a window ( 13 ). 14. Obturator according to one of claims 1 to 13, characterized ge indicates that the obturator consists essentially of one absorbable inorganic material, especially tricalcium phosphate ceramic, or a resorbable organic material, especially polylactide. 15. Obturator according to one of claims 1 to 14, characterized ge indicates that the obturator is a non-absorbable Support structure for a resorbable matrix, in particular made of Calcium hydroxyapatite, aluminum oxide or titanium.   16. Obturator according to one of claims 1 to 15, characterized in that the obturator ( 1 ) is assigned a cutting rotating or oscillating tool, the dimensions of which correspond to the cavity ( 5 ) with the standardized dimensions. 17. Obturator according to one of claims 1 to 15, characterized in that the obturator ( 1 ) is a cutting rotating or oscillating tool, the dimensions of which correspond to a part of the cavity ( 5 ) with the standardized dimensions, and a template for attaching the Tool when inserting the cavity ( 5 ) in the bone ( 6 ) are assigned.