WO2005009260A1

WO2005009260A1 - Distraction module for widening a person's jaw

Info

Publication number: WO2005009260A1
Application number: PCT/BE2004/000108
Authority: WO
Inventors: Hugo De Clerck; Norbert De Jonghe
Original assignee: Hugo De Clerck; Norbert De Jonghe
Priority date: 2003-07-24
Filing date: 2004-07-26
Publication date: 2005-02-03
Also published as: BE1015618A6

Abstract

The invention concerns a distraction apparatus with an expansion module (1) for widening a person's jaw (9,24), whereby the two opposite far ends (2,3) of the expansion module (1) are equipped with a connecting organ (4,5) which works in conjunction with at least a supporting element (6,7) which must be fixed to the bone (8) of the jaw (9,24), and whereby said supporting element (6,7) comprises a mounting head (10) with a recess (11), whereby this mounting head (10) is provided with an access (12) to said recess (11) which can be sealed by means of a detachable cap (14), and with an opening (15) which also leads to said recess (11), and whereby said connecting organ (4,5) can be brought into said recess (11) while it extends through said opening (15), such that the expansion module (1) can undergo a rotational movement in relation to the mounting head (10) while it is being retained in said recess (11) via said connecting organ (4,5) by means of the cap (14).

Description

DISTRACTION MODULE FOR WIDENING A PERSON'S JAW The invention concerns a distraction apparatus with an expansion module for widening a person's jaw, whereby the two opposite far ends of the expansion module are equipped with a connecting organ which works in conjunction with at least a supporting element which must be fixed to the bone of the jaw. Patent document WO 01/50976 describes such a distraction apparatus whereby an expansion screw rests freely between two plate-shaped anchors which are to be fixed to the maxilla. However, this distraction apparatus cannot be provided in the case of persons having what is called a low palate, whereby the palate of the oral cavity between the teeth is practically flat, or who have a very small maxilla. This is especially the case with young children. Moreover, it is very time-consuming and it requires a lot of dexterity to place the expansion screw between the aforesaid anchors. In particular, the expansion screw has to be positioned very precisely between the anchors and it has to be maintained in this exact position on the one hand, whereas the expansion screw has to be simultaneously tightened by revolving it around its axis on the other hand so as to clamp it between the anchors. There is also a possibility that the expansion screw will come loose from the anchors after a while, for example while consuming a meal, and is swallowed. Patent US 5 885 290 describes a distraction apparatus which is fixed to the jaw for example by means of screws and which can be used neither with children having a small maxilla, nor with persons having a low palate. Moreover, this distraction apparatus easily causes inflammations, and leavings stay behind between parts of the expansion screw. Widening a maxilla is preferably done at as young an age as possible, however. With the existing distraction apparatuses, this is not possible at present. The invention aims to remedy these disadvantages by providing a distraction apparatus which can be used for persons having a low palate as well as for children and persons with a very small maxilla, and which moreover can be fixed to a jaw in a very efficient and simple manner. To this aim, said supporting element comprises a mounting head with a recess, whereby this mounting head is provided with an access to said recess which can be sealed by means of a detachable cap, and with an opening which also leads to said recess, and whereby said connecting organ can be brought into said recess while it extends through said opening, such that the expansion coupling can undergo a rotational movement in relation to the mounting head while it is being retained in said recess via said connecting organ by means of the cap. Practically, said supporting element comprises a fixing bar which connects to the mounting head in order to fix it to the bone of the jaw. In an advantageous manner, said fixing bar is threaded so that it can be fixed in the bone of the jaw, such that the above-mentioned supporting element forms a screw whose head consists of said mounting head. According to an interesting embodiment of the distraction apparatus according to the invention, the above-mentioned connecting organ has a coupling bar which extends crosswise in relation to the longitudinal length of the expansion module Said coupling bar is preferably fixed in a separate supporting element on either side. According to a special embodiment of the distraction apparatus according to the invention, said coupling bar extends freely through an eye provided on the corresponding far end of the expansion module. Other particularities and advantages of the invention will become clear from the following description of a few special embodiments of the invention; this description is given as an example only and does not limit the scope of the claimed protection in any way; the figures of reference used hereafter refer to the accompanying drawings. Figure 1 schematically represents a view of the palate seen from the mouth with a distraction apparatus according to a first embodiment of the invention. Figure 2 is a schematic front view of the distraction apparatus according to line II-II in figure 1. Figure 3 is a schematic longitudinal section according to line III-III of figure 1 of the distraction apparatus according to the invention. Figure 4 is a schematic longitudinal section of a supporting element according to line IN-IN from figure 3. Figure 5 is a schematic side view of a cap which is to work in conjunction with the supporting element from figure 4. Figure 6 is a schematic view of the palate seen from the mouth with a distraction apparatus according to a second embodiment of the invention. Figure 7 is a schematic front view of the distraction apparatus according to line NII-NII from figure 6. Figure 8 is a schematic side view of a supporting element according to the invention which can be used for the distraction apparatus, according to said second embodiment of the invention. Figure 9 is a schematic side view of a supporting element according to line NII-NII from figure 6 with a part of a connecting organ. Figure 10 is a schematic longitudinal section of the expansion module according to line X-X from figure 6 when it is situated in an utmost tightened position. Figure 11 is a schematic longitudinal section of this expansion module according to line X-X from figure 6 when it is situated in an utmost short position. Figure 12 is a schematic side view of a part of a skull with a maxilla upon which is mounted a distraction apparatus according to a third embodiment of the invention. hi the different figures, the same figures of reference refer to identical or analogous elements. The invention in general concerns a distraction apparatus with an expansion module for widening a person's jaw. This expansion module is preferably longitudinal and it is fixed via the opposite far ends thereof to supporting elements which are to be anchored in the bone of a jaw. The expansion module makes it possible to gradually enlarge the distance between these supporting elements in order to widen the jaw upon which the distraction apparatus is mounted. Whereas for young patients, such as children, it is sufficient to fix the distraction apparatus on the part of the jaw that is to be widened, it may be appropriate, for example for adults, to split the jaw in two parts by providing a saw cut between the supporting elements upon which the expansion module is mounted. When these supporting elements are gradually moved away from each other by tightening the expansion module, more bone will be gradually formed between these supporting elements, and the jaw will thus widen. Figures 1 to 3 schematically represent a first embodiment of the distraction apparatus according to the invention. This distraction apparatus is provided with an expansion module 1 which is provided with connecting organs 4 and 5 on two opposite far ends 2 and 3. Via these connecting organs 4 and 5, the expansion module is fixed on supporting elements 6 and 7 which are anchored in the bone 8 of a jaw 9. Each supporting element 6 and 7 has a mounting head 10 in which is provided a recess 11, as represented in figures 3 and 4. This mounting head 10 has the shape of a cylinder, in which said recess 11 extends centrally. Via an access 12, the recess 11 opens onto the top face 13 of the mounting head 10. The access 12 is formed of an internally threaded bore which is coaxial to the cylinder-shaped mounting head 10 and which can be sealed by means of a cap 14. Figure 5 represents such a cap 14 which is cylindrical as well and which is externally threaded, such that it can be screwed in the access 12 in order to close the latter. The cap 14 thus forms a bolt. Further, said recess 11 leads to the lateral surface of the mounting head

10 via an opening 15, or in other words to the housing of the cylinder forming this mounting head 10. The connecting organs 4 and 5 are in said recess 11 of the respective supporting elements 6 and 7, whereby the corresponding openings 15 are directed towards each other. Thus, the expansion module connects both supporting elements 6 and 7, whereas the connecting organs 4 and 5 extend through said opening 15. More particularly, the connecting organ 4, 5 is placed in the recess 11 via said access 12, whereby it is guided through said opening 15 which extends up to the access 12. In order to seal the access 12, such that the connecting organ 4, 5 is retained in the recess 11, said cap 14 is fixed in the access 12. After the cap 14 has been provided, the expansion module 1 can undergo another rotation in relation to the mounting head 10, while it is being held via the connecting organ 4, 5. More particularly, the latter can be moved somewhat according to a rotational movement in the recess 11. To this end, one makes sure for example that there is a small free space between the cap 14 and the connecting organ 4 and 5. The far end of the cap 14 which connects to the connecting organs 4 and 5 is made concave, such that the connecting organs 4 and 5 in the thus formed concave space can undergo a movement, more particularly a rotational movement. In order to enable the rotational movement of the expansion module 1, said opening 15 forms a slot which connects to the access 12, whereby the width of the slot is smaller than the size of the connecting organs 4 and 5 in a direction crosswise to the longitudinal direction of the expansion module. The latter makes sure that the expansion module 1 cannot come loose from the supporting elements 6 and 7 through the opening 15. The supporting elements 6 and 7 are further provided with a fixing bar 16 which connects to the mounting head 10. Via this fixing bar 16, the fastening elements 6 and 7 are fixed to the bone 8 of the jaw 9. According to the embodiment of the distraction apparatus according to the invention, represented in figures 1 to 5, this fixing bar 16 has a screw thread 17 on the far end opposite to the mounting head 10. Via this screw thread 17, the supporting elements 6 and 7 are to be screwed in the bone 8 of the jaw 9 in order to fix it. Thus, the supporting elements 6 and 7 form a screw whose head consists of said mounting head 10. In order to mount the distraction apparatus to a jaw 9, in a first step, a supporting element 6 and 7 is screwed in the bone of the jaw on either side of the part of the jaw to be widened. The part 18 of the fixing bar 16, which is made somewhat conical and has a circular cross section, extends through the gums surrounding the bone 8 of the jaw 9. In a second step, the connecting organ 4 or 5 of either one of both far ends 2 or 3 of the expansion module 1 is brought via the access 12 in the recess 11 of a first supporting element 6 or 7. Next, this access 12 is sealed with the above-mentioned cap 14, such that the corresponding connecting organ 4 or 5 is retained in the recess 11. Finally, the connecting organ 4 or 5 of the other far end 2 or 3 of the expansion module 1 is brought in the recess 11 of the latter via the access 12 of the other supporting element 6 or 7. This is done in a very simple manner, without much dexterity being required, since the expansion module 1 can undergo a rotational movement in relation to the mounting head 10 of the first supporting element 6 or 7, without coming loose from the latter. After the corresponding connecting organ 4 or 5 has been fixed to this second supporting element 6 or 7, the corresponding access 12 is sealed with a cap 14 as well. The part of the connecting organ 4 and 5 which rests in said recess 11 is cubical and connects to said far end 2 or 3 via a neck-shaped constriction as represented in figure 3. Naturally, it goes without saying that it may have vary different shapes and that it can rest in the recess 11 via a spherical part, for example. The connecting organ may for example also have the shape of a T, whereby a cross-shaped recess 11 is provided in the mounting head 10 which leads via four openings to the lateral surface of this mounting head 10. Figures 6 to 11 represent a second embodiment of the distraction apparatus according to the invention. This distraction apparatus differs from the preceding embodiment in that, among others, each of the far ends 2 and 3 of the distraction module are fixed to the jaw 9 via two supporting elements, such that four supporting elements 6, 6', 7 and 7' in total are provided. Further the connecting organs 4 and 5 have a coupling bar 19 which extends crosswise, and preferably perpendicular, in relation to the longitudinal direction of the expansion module 1, such that the connecting organs 4 and 5 assume the shape of a T. The part of the connecting organ 4 and 5 which is fixed to the respective far ends 2 and 3 of the expansion module 1 is hereby provided with an eye 20 through which the coupling bar 19 freely extends. The coupling bar 19 is fixed on either side in a supporting element 6, 6 7 and 7' via its far end. Thus, each coupling bar 19 of the respective connecting organ 4 and 5 is fixed to two supporting elements 6, 6' and 7, 7' placed at a short distance next to each other. The supporting elements 6, 6 7 and 7', represented in greater detail in figures 8 and 9, have the shape of a screw whereby the head is formed of a mounting head 10 in which has been provided a slot-shaped recess 11 which leads to the lateral surface of said mounting head 14 on two opposite sides, and thus forms two openings 15 which extend into the top face 13. Further, the top face 13 of this mounting head 10 has an access 12 to the recess 11 which can be sealed by means of a cap 14. The mounting head 14 is cylindrical and is provided with external screw thread 21, whereby the cap 14 forms a case with a cylindrical, threaded excavation. Thus, the access 12 is sealed by placing said cap 14 over the mounting head 14 and by tightening it via said external screw thread 21, as is schematically represented in figure 9. The above-mentioned coupling bar 19 is hereby placed in the recess 11, such that it is clamped in it between the cap 14 and the part of the fixing bar 16 which connects to the mounting head 10. In the top face 22 of the cap 14 is provided a recess 23 which makes it possible to mount the cap 14 on the mounting head 14 via an appropriate tool, such as for example a screwdriver. When the distraction apparatus, according to this second embodiment of the invention, is mounted on a jaw 9, the above-mentioned four supporting elements 6, 6', 7 and 7', in a first step, are placed on either side of the jaw 9, grouped two by two. Next, a first far end 2 or 3 of the expansion module 1 is fixed via the corresponding connecting organ 5 or 6 to two supporting elements 6, 6' or 7, 7' placed next to each other by providing the corresponding coupling bar 19 on either side in the recess 11 of the respective supporting elements 6, 6' or 7, 7'. The respective recesses 11 of the two supporting elements placed next to each other should hereby extend in each other's prolongation. After a corresponding cap 14 has been fixed onto each of said supporting elements 6, 6' or 7, 7', the above-mentioned far end 2 or 3 of the expansion module 1 will be situated between these two supporting elements 6, 6' or 7, 7' situated next to each other, whereas this expansion module can move freely over the coupling bar 19. The expansion module can thus move according to the longitudinal direction of the coupling bar 19 on the one hand, and it can undergo a rotational movement around this coupling bar 19 in relation to the corresponding mounting heads 10 of both supporting elements 6, 6' or 7, 7'. As it is thus possible to move the expansion module 1 in relation to these first two mounting heads 10, the other far end 2 or 3 of the expansion module 1 can simply be fixed in the corresponding recesses 11 of the other two supporting elements 6, 6' or 7, 7' via the other connecting organ 5 or 6. Finally, the latter two supporting elements 6, 6' or 7, T are sealed by means of a cap 14. The embodiments of the distraction apparatus according to the invention which are described above are particularly well suitable to be mounted in the oral cavity on the palate of a person. Figure 12 represents a third embodiment of the distraction apparatus according to the invention which is fixed sidelong on the maxilla 24 of a person in order to extend this jaw 24. This distraction apparatus is also provided with an expansion module 1 which is fixed at both far ends with a connecting organ in a mounting head 10 of respective supporting elements 6 and 7. These two supporting elements 6 and 7 are placed on either side of a saw cut 25 on the bone of the maxilla 24, such that the surfaces of the saw cut lying opposite each other can be gradually shifted towards each other by means of the expansion module 1. The saw cut 25 is provided in the bone of the maxilla 24 in a plane which is preferably parallel to the plane formed by the dental arc of this jaw. A first supporting element 6 is fixed to the lower side of what is called the zygoma, such that it is fixed to the skull, whereas the second supporting element 7 is mounted on the part of the maxilla 24 situated under said saw cut 25, and can thus be moved in relation to the skull. Apart from a mounting head 10 which connects to a fixing bar 16, these supporting elements 6 and 7 have what is called an osteosynthesis plate 26 which makes it possible to anchor the supporting elements 6 and 7 with screws 27 in the bone of the maxilla 24. The osteosynthesis plate 26 particularly extends in the prolongation of the fixing bar 16 at the far end of the latter situated opposite to the mounting head 10. The mounting head 10 of the supporting element 6 and 7 of the distraction apparatus, according to this embodiment of the invention, preferably corresponds to the mounting head 10 of the above-described first embodiment of the distraction apparatus which is represented among others in figures 3 and 4. The expansion module 1 which is represented in detail in figures 3, 10 and 11 has two coaxial bars 28 and 29 which each connect to one of the far ends 2 and 3 of the expansion module 1. These bars 28 and 29 are provided with external thread having opposite directions, and they are connected to each other via a sleeve 30 provided with internal thread. When this sleeve 30 is rotated around the longitudinal axis in relation to the bars 28 and 29, the latter is moved in the opposite sense. Thus, it is possible to extend the expansion module 1 and to exert a pressure force on the supporting elements 6, 6', 7 and 7'. A first bar 28 has an axial cylindrical recess 31 with a diameter which is larger than the diameter of the second bar 29, such that the latter fits in this cylindrical recess 31 when the expansion module is in its shortest position as represented in figure 11. Naturally, the invention is not restricted to the above-described embodiments of the distraction apparatus according to the invention represented in the accompanying drawings. Thus, the expansion module may for example consist of any element whatsoever which makes it possible to gradually enlarge the distance between its far ends.

Claims

1. Distraction apparatus with an expansion module (1) for widening a person's jaw (9,24), whereby the two opposite far ends (2,3) of the expansion module (1) are equipped with a connecting organ (4,5) which works in conjunction with at least a supporting element (6,7) which must be fixed to the bone (8) of the jaw (9,24), characterised in that said supporting element (6,7) comprises a mounting head (10) with a recess (11), whereby this mounting head (10) is provided with an access (12) to said recess (11) which can be sealed by means of a detachable cap (14), and with an opening (15) which also leads to said recess (11), and whereby said connecting organ (4,5) can be brought into said recess (11) while it extends through said opening (15), such that the expansion module (1) can undergo a rotational movement in relation to the mounting head (10) while it is being retained in said recess (11) via said connecting organ (4,5) by means of the cap (14).

2. Distraction apparatus according to claim 1, characterised in that said opening (15) forms a slot which connects to said access (12), whereby the width of the slot is smaller than the size of the connecting organ (4,5) in a direction crosswise to the longitudinal direction of the expansion module (1).

3. Distraction apparatus according to claim 1 or 2, characterised in that said supporting element (6,7) comprises a fixing bar (16) which connects to the mounting head (10) in order to fix it to the bone (8) of the jaw (9,24).

4. Distraction apparatus according to claim 3, characterised in that said fixing bar (16) comprises screw thread (17) in order to be fixed in the bone (8) of the jaw (9,24), such that said supporting element (6,7) forms a screw whose head consists of said mounting head (10).

5. Distraction apparatus according to claim 3, characterised in that the far end of said fixing bar (16) opposite to said mounting head (10) connects to an osteosynthesis plate (26) which is to be fixed to the jaw (24) by means of screws (27).

6. Distraction apparatus according to any one of claims 1 tot 5, characterised in that said mounting head (10) is cylindrical, whereby said access (12) leads to the top face (13) of this cylinder, while said opening (15) leads to the housing of the cylinder.

7. Distraction apparatus according to any one of claims 1 to 6, characterised in that said access (12) is formed into said recess (11) by a bore, whereby the above-mentioned cap (14) comprises a bolt which is to be fixed in said bore in order to seal said access (12).

8. Distraction apparatus according to claim 7, characterised in that the far end of said bolt which connects to the connecting organ (4,5) is made concave.

9. Distraction apparatus according to claim 6, characterised in that the above-mentioned cap (14) has a cylindrical excavation, such that it can be placed over the mounting head (10) in order to seal said access (12).

10. Distraction apparatus according to any one of the claims 1 to 9, characterised in that said connecting organ (4,5) has a coupling bar (19) which extends crosswise in relation to the longitudinal direction of the expansion module (1).

11. Distraction apparatus according to claim 10, characterised in that said recess (11) has a cross section in the shape of a cross.

12. Distraction apparatus according to claim 10 or 11, characterised in that the above-mentioned coupling bar (19) must be provided on either side in a separate supporting element (6,7).

13. Distraction apparatus according to claim 12, characterised in that the above-mentioned coupling bar (19) extends freely through an eye (20) which is provided on the corresponding far end (2,3) of the expansion module (1).

14. Distraction apparatus according to any one of the claims 1 to 13, characterised in that the above-mentioned expansion module (1) comprises two coaxial bars (28,29) which each connect to one of the far ends (2,3) of the expansion module (1), whereby these bars (28,29) are provided with screw thread having opposite directions, and are connected to each other via a sleeve (30) provided with internal screw thread, such that when this sleeve (30) is rotated around the longitudinal axis in relation to said bars (28,29), the latter are moved in the opposite direction.

15. Distraction apparatus according to claim 14, characterised in that one of the above-mentioned bars (28) has an axial cylindrical recess (31) with a diameter which is larger than that of a second one of the above-mentioned bars (29), such that the latter bar (29) fits in this cylindrical recess (31).