It is well known that the orthodontic correction technique provides to the tooth to be treated one or more forces of predetermined intensity and direction in order to correct its position.

The orthodontic devices consist generally in wires, brackets, elastic bands or like which are connected on one side to the tooth to be treated and on the other side on to one or more anchor points constituted by means to be implanted into the palatal vault or alveolar processes.

These anchor points or screws are generally provided with a threaded end to be screwed into the palatal bone while the other end has a shaped head to receive one or more wires of orthodontic connection.

After having taken a mouth print with implanted devices in situ, mouth plaster casts are realized.

The orthodontic structure is then prepared on the plaster pattern so that it connects the teeth to the implanted device. Subsequently these devices are controlled in the patient's mouth.

More particularly said controls concern the length of orthodontic devices (wires and others), their pre-stressing and/or passivity in order to check whether or not they can develop the traction and or thrust forces required for the intended correction.

The assembling stage provides connection by welding of orthodontic devices to one another and to the anchor screws so that to obtain the required performances. Welding must necessarily be carried out at the bench and not in the patient's mouth.

Quality of the orthodontic correcting device clearly depends on the precision degree of the final assembling stage.

Absence of harmful stress that could otherwise interfere on to implants into the bone depends on this precision.

One of the main drawbacks of the known technique is due to inaccuracies arisen in the assembling stage caused by the necessity of preparing the orthodontic device outside the oral cavity for setting the lengths and welding

the orthodontic wires to one another or between the bars and anchor members.

The step of taking outside the orthodontic devices for their welding often involves a loss of precision of the weldings or castings can cause serious consequences on the actual function of the apparatus.

The present invention aims to overcome the above mentioned drawbacks.

More particularly a first object of the present invention is to provide a connecting element for orthodontic devices to an implant inserted into the palatal vault or other oral sites, allowing the complete assembling of the whole orthodontic system inside the oral cavity without effecting pre-setting operations outside the mouth that prevent further adjustments of the orthodontic devices in the oral cavity.

Another object of the present invention is to allow the fine and precise adjustment directly in the oral cavity of the prepared orthodontic devices by acting on the length and shape of the orthodontic devices, the direction and intensity of the traction and/or thrust forces required for the orthodontic correction.

In the frame of the present invention another object is to carry out a connecting elements of the implant within the palatal vault or within the alveolar crest with the traction and/or thrust systems of the orthodontic devices, allowing to assemble the orthodontic system inside the oral cavity.

Still a further object of the invention is to provide a connecting element allowing to decrease considerably or even remove the possibility of errors related to regulation of length, direction and position of the traction, anchor and/or thrust means to be applied on to the tooth to be corrected.

The foregoing objects are attained by a connecting element in between an implant and the palatal vault or alveolar crest with orthodontic devices adapted to carry out orthodontic correcting treatments comprising fastening means for the removable connection to said fixed implant which according to the wording of the main claim is characterized by comprising: -a central generally cylindrical body having two coaxial connected holes with different diameter, the upper hole being adapted to receive the head of an implant fastening screw and the lower hole being adapted to receive the shank of said screw, said central body being provided with an appendix to be lodged on a recess of the head of said endoosteal implant or the head of a

transmucuous intermediate piece and at least a hold member connected to said central body with a generally flat development and arranged radially to the axis of said body, provided on at least one surface anchor means for said orthodontic devices.

The connecting element of the present invention advantageously allows to carry out multiple connections between orthodontic devices through a mechanical connection or fixing with acrylic resins or other materials inside the oral cavity.

Furthermore the invention advantageously allows to assemble the orthodontic system without removing it from the oral cavity and consequently obtain a fine regulation of the length and precision of the used orthodontic devices, thus a better control of the forces acting on the dental arch and the implanted bodies or orthodontic implants.

The objects and advantages of the invention will be more apparent from following description of preferred embodiments of the invention given as an illustrative but non limiting example and shown in the accompanying sheets of drawings in which: -Fig. 1 is an isometric view of a constructional form of the connecting element of the invention; -Fig. 2 is an over turned view of the element of Fig. 1; -Fig. 3 is a sectional view of the element of Fig. 1 taken along the line lil-lil ; -Fig. 4 is a bottom view of the element of Fig. 1; -Fig. 5 is a bottom view of a variation of the element of Fig. 1 in which the appendix of the central body is cylindrical instead of hexagonal ; -Fig. 6 is an exploded sectional view of the connecting element of the invention connected before being assembled with the endoosteal implant ; -Fig. 7 is sectional view of the connecting element of the invention fixed to the endoosteal implant ; -Fig. 8 is a partial sectional view of a hold member and an anchoring system of the connection orthodontic devices ; -Fig. 9 is a view of another anchoring system of the orthodontic devices to the hold member; -Fig. 10 is a view of another variation of the anchoring means of the orthodontic devices to the hold member; -Fig. 11 shows a further variation of the anchoring means; and

-Fig. 12 shows still another variation of the means anchoring the orthodontic devices to the hold members.

Referring now to the figures of the drawings the connecting element of the endoosteal implant to be installed in the palate with the orthodontic devices such as wires or metal bars connecting the endoosteal implant or screw with one or more teeth, is generally indicated with reference numeral 1 and consists of a central body 10 in which there are two coaxial holes 11 and 12. The upper hole 11 can receive the head of a screw 20 for fixing the connecting element 10 to the screw or endoosteal implant 30 that can be seen in Figg. 6 and 7 and will be explained here in after. From the central body 10 three hold members 13 layin on the same plane are diverging along radial direction. Each of said hold member 13 has a generally flat development and is provided with anchor means for wires, bars or generally any orthodontic device connecting the tooth to the connecting element one. In the embodiment of Figs. 1 to 9, the anchor means are holes 14 that in the embodiment of the above mentioned figures are two holes. Through these holes the connection device is threaded, that may be constituted by a steel or nylon wire, a bar or even an elastic means. These devices may exert directly a traction or thrust action on the tooth in respect of the endoosteal implant or may simply block the teeth with the implant (indirect anchorage). The connection device can be threaded inside one or two holes 14 and fixed with different means. One of these means may consist in bending it on itself, another means in blocking it with a resin such as an acrylic or light curing resin or composite material as shown in Fig. 9. Other anchoring means may consist in texturing the surface of the hold member. In Fig. 10 the surface of the hold member 13 that in the embodiment of Fig. 10 is indicated with numeral 15, has little indents 16 as a grip means for the adhesive material for joining the wire to one another or the bars to the connecting element. The complete block of wire 40 is carried out by using resins such as light sensitive or self setting resins or with composite adhesive materials or equivalent adhesive means.

Referring again to the central body 10, it is to be noted that said body has an appendix 17 in respect of the lower plane formed by the hold member 13, the outer surface of said appendix being octagonal or polyhedral as shown in Figg.

2 and 4, while in the embodiment of Fig. 5 which is a bottom view of the connecting element, the appendix now indicated with reference numeral 18,

has a circular shape. These two ways of making the appendix arise from the need of having at disposal different solutions whether the endoosteal implant is only one or there are two endoosteal implants to be connected also to each other. In the case of one endoosteal implant only it is important the orientation taken by the connecting element 1 and more particularly by the hold member 13 in respect of the tooth. It is clear that the hold member 13 must be positioned in the direction sighting the tooth and it is important that this direction is not changed during the orthodontic application. To this purpose the appendix 17 has a polyhedral shape that will be lodged in the initial portion 32 of hole 31 on which said appendix of the hold member is placed as shown in Figg. 6 and 7. On the contrary when in the palate or alveolus two endoosteal implants are connected by a single connection device, it is to be understood that the orientation of the connecting elements is substantially obliged by the action of the single wire and therefore the cylindrical shape of appendix 18 shown in Fig. 5 will be sufficient for this purpose. It is also to be noted that the connecting element in the embodiments in Fig. 1 and Fig. 5 is illustrated with three hold members 13 arranged substantially at 45 degrees to one another. However in the constructional stage and in case the hold members are two or more, the angle between two subsequent hold members may vary for instance between 30 degrees and 45 degrees or between 30 degrees and 60 degrees. It is also advantageously possible to make a connecting element with only one hold member 13 or it is also possible to use connecting elements with several hold members by varying the functionality that is removing by a cutting or shearing tool, the hold members in excess for the intended application.

In operation the present invention provides that once the implantation of screw 30 in the palate or other site is effected so that the threaded portion A is inserted into the bone and a cylindrical portion B protrudes crossing the cortical wall, the periosteum and emerges from the gum, then the connecting element 1 is applied. In some cases in order to emerge from the gum a transmucuous element is applied, having the function of spacer between implant and connecting element still provided with polyhedral antirotation device, but in the case of the embodiment of the invention the connecting element 1 is applied directly to the screw 30 implanted in the bone. Moreover instead of using the screw 30, for the

endoosteal implant cylinders, steps and the like may be used that become blocked in the bone by biochemical phenomena. In the embodiment of Fig. 6, the connecting element has an appendix of octagonal shape which therefore must be oriented with the hold member or members in the intended direction before inserting the appendix 17 in the corresponding polyhedral seat 32 of screw 30. Once the connecting element 10 is lodged on the screw 30, then the element 10 is fixed through the screw 20 has shown in Fig. 7. When the hold member is provided with holes as shown in Figg. 8 or 9, it is easier to thread the wire constituting the orthodontic device connecting the teeth before its positioning on seat 32 of screw 30 and fixing with the screw 20 and this for clear reasons of practicality. On the contrary when the hold member has an indented surface 16 as shown in Fig 10, the connecting element may be finally fixed beforehand and then the wire 40 is applied with subsequent blocking through instantaneous setting resins.

Fig. 11 shows an anchorage between two wires 50 inserted in holes 14 and made on the surface 131 of the hold member 13. These wires are then blocked with application of instantaneous setting resins. In a similar way Fig. 12 shows two holes 50 leaning on the corrugated surface 151 of the hold member 15 to be then blocked with instantaneous setting resin.

It is to be noted that the hold member 13 may be provided with anchoring means different from those described above, such as dead holes or grooves in which the orthodontic device like wire or the like is inserted and on which a suitable adhesive material may then be applied in order to seal finally together the hold member and the orthodontic device. Moreover the connecting element of the invention and therefore also the hold member may be made in any suitable material such as stainless steel, titanium or plastic material.

From the foregoing description it is clear the advantage of the present invention allowing to apply the orthodontic devices connecting teeth and the endoosteal fixed implants directly in the patient's mouth thus avoiding any kind of welding that obliged to prepare these connections at the bench thus requiring an extreme precision.

According to the invention on the contrary it is now possible to carry out the connection between tooth and endoosteal implant directly on the palate or other site of the mouth where the implant was fixed and then securely fastening these connections without troubles for the patient.