WO2008051163A1

WO2008051163A1 - Dental system

Info

Publication number: WO2008051163A1
Application number: PCT/SE2007/050784
Authority: WO
Inventors: Per Olof Leike
Original assignee: Biomain Ab
Priority date: 2006-10-26
Filing date: 2007-10-26
Publication date: 2008-05-02
Also published as: EP2076204A1; CA2667244A1; EP2076204A4

Abstract

A dental system and members of said system, for determining a suitable angle for a dental superstructure with a non-linear screw-channel are provided. This system comprises a bore angle member, comprising a head portion (41, 61), and a bore angle connector (51, 71) having a bottom portion (52, 72) for connection to said head portion of said bore angle member, whereby said bore angle member and said bore angle connector are pivotably connected to each other. A distance member (80) is also provided.

Description

DENTAL SYSTEM

Field of the Invention

This invention pertains in general to the field of a dental system for determining an angle in a dental superstructure comprising a non-linear screw-channel.

Background of the Invention

The goal of a dental implant system is to restore the patient to normal function, comfort, aesthetic, speech and health regardless of the current oral condition. These implant systems are based on the implantation of dental implants, such as dental implants made of biocompatible titanium, through insertion into the patient's jawbone. In this respect, the use of biocompatible titanium started in Sweden as early as 1950, and has since then been further developed and spread world-wide. During the 1980' s a number of implant systems entered the world market. Methods are known in the art to attach a dental superstructure to an implant. A couple of methods are based on the use of a screw member. Theses screw members can attach the superstructure to the implant, either directly or via spacers .

When implants are implanted in the mouth of a patient who has been without teeth for some time problems arise due to degeneration of bone. If a person has been without teeth for some time, the jawbone that is not under strain of natural teeth or implants, will dissolve and assimilate over time, yielding less bone material for the proper anchoring of a dental implant. To find enough bone for optimal implantation, the implant has to be angled so that the general axis of the implant projects out of the mouth. Fixing a superstructure with a screw member in a straight screw channel to such implants necessitates that the mouth of the screw channel may be forced to be placed on a visual surface of the dental superstructure. Also, the optimum placement of the implant, due to the present dental situation, often results in a non-optimum placement of the dental superstructure in terms of the patient's aesthetics, phonetics and bite. Therefore, there is a need in the dental field for greater freedom of placement of a dental implant in order to optimize the stability and success of the implantation, while still achieving good aesthetics, phonetics and bite of the patient. Furthermore, in the above mentioned dental situation there is a need to be able to use an implant placed optimally with regard to the dental situation, that is, the anatomy of the jawbone, while still allowing the dental superstructure to be applied in an optimal way to said implant, such that the mouth of a screw channel not is visible from outside the mouth of the patient.

The means already known in the art for achieving this goal include the use of angled spacers and dental superstructures attached to the implant with adhesive or with other techniques not based on the use of a screw member. The angled spacers have many drawbacks and are characterized by adding significant height to the superstructure, multiple sources of errors, since the coordination of multiple parts undoubtedly leads this, an unnecessarily high price, as a result of the multiple parts and multiple manufacturing steps, increased risk of bacteriological attack, due to the several corners and surfaces exposable to this, weaker screw for the attachment of the dental bridge, since no follow-up draft of said screw is possible since a structure is applied on top of said angled spacers. It also results in an increased complexity of the attachment of the superstructure to the implant. US 6,848,908 discloses an arrangement including an angled spacer element of this kind, including a first passage and a second passage. The first passage is operative to fasten said spacer element in an implant, and the second passage is operative to fasten a superstructure on said spacer element. Superstructures attached to an implant without using a screw member results in less strength, difficulties in detachment and also incompatibility problems with commercially available implant systems of today.

There is therefore a need, among others, for a method of attaching or detaching a dental superstructure to a dental implant at a chosen angle without adding additional height to the chosen superstructure.

Thus, there is a need for a new superstructure that may be fastened to an implant without angled spacer elements or superstructures attached to the implant with only adhesive or with other techniques not based on the use of a screw member. There is also need for a simpler, faster and cheaper production method of dental superstructures, while still providing the benefits according to above. Furthermore, there is a need to provide for the possibility of a simple assembly ex situ (outside the patient's mouth) and application in situ (in the patient's mouth).

Moreover, there is a need to improve the conversion from a patient specific dental model, made by a dental technician or dental surgeon, into a final superstructure to be connected to an osseointegrated dental implant.

Hence, an dental system for aiding the manufacturing of an improved superstructure, would be advantageous, and in particular a superstructure allowing for the exclusion of angled spacer elements or fastening of a superstructure to an implant by adhesives, without being forced to place the mouth of the screw channel on a visual surface of the dental superstructure would be advantageous. Summary of the Invention

Accordingly, the present invention seeks to mitigate, alleviate or eliminate one or more of the above-identified deficiencies and to provide a dental system, a bore angle member, a bore angle connector, and a distance member of the kind referred to, and a manufacturing method thereof. For this purpose a dental system is provided for determining a suitable angle for a dental superstructure with a non-linear screw-channel, said system comprising a bore angle member, comprising a head portion, said bore angle member being configured to be mounted on a dental implant, and a bore angle connector having a bottom portion for connection to said head portion of said bore angle member, whereby said bore angle member and said bore angle connector are pivotably connected to each other, and a bore angle member is provided, configured to be mounted on a dental implant, said bore angle member comprising a head portion configured to be pivotably connected to a bore angle connector, and a bore angle connector is provided, comprising a main portion and a bottom portion, said bottom portion being configured to be pivotably connected to a bore angle member, and a distance member is provided, configured to be connected to a bore angle member or a bore angle connector, such that the pivoting angle between said bore angle member and said bore angle connector is limited. Advantageous features of the invention are defined in the dependent claims.

Brief Description of the Drawings These and other aspects, features and advantages of which the invention is capable of will be apparent and elucidated from the following description of embodiments of the present invention, reference being made to the accompanying drawings, in which Fig. 1 is an illustration showing a cross-section of a superstructure according to an embodiment;

Fig. 2 is an illustration showing a cross-section of a superstructure according to an embodiment; Fig. 3 is an illustration showing a cross-section of a superstructure according to an embodiment;

Fig. 4 is schematic cross-section view of a bore angle screw according to an embodiment;

Fig. 5 is schematic cross-section view of a bore angle connector according to an embodiment;

Fig. 6 is schematic cross-section view of a bore angle screw according to an embodiment;

Fig. 7 is schematic cross-section view of a bore angle connector according to an embodiment; Fig. 8a is schematic cross-section view of a distance member according to an embodiment;

Fig. 8b is schematic cross-section view of a distance member according to an embodiment;

Fig. 9a is schematic cross-section view of an system according to an embodiment;

Fig. 9b is schematic cross-section view of an system according to an embodiment;

Fig. 10a is schematic cross-section view of bore angle connector according to an embodiment; Fig. 10b is schematic cross-section view of bore angle connector according to an embodiment;

Fig. 11 is schematic cross-section view of an arrangement according to an embodiment; and

Fig. 12 is schematic cross-section view of an arrangement according to an embodiment. Description of embodiments

The following description focuses on embodiments of the present invention applicable to a superstructure, and also to a method of manufacturing said superstructure. The present invention discloses, according to Fig. 1, a superstructure, comprising a main body, comprising a screw-channel 1 with a first mouth 2, through which screw- channel 1 a screw member is to be inserted, and a screw member seat 3 with a second mouth 4, for providing support to the head of said screw member during fixation of said dental superstructure to a spacer element or an implant 5 through said second mouth 4, whereby a communication is obtained between said first and second mouth, wherein at least one part of a central axis of said screw-channel 1 differs from a central axis of said second mouth 4. In this way the mouth 2 of the screw channel 1 may be located such that the superstructure may be attached/detached to a dental implant or a spacer element 5 where the mouth 2 of the screw channel 1 not is visible from outside the patients mouth. Such a superstructure will herein be referred to as a superstructure with a non-linear screw- channel. Arrangements of non-linear screw-channels and how these may be configured in superstructures in respect of dental implants are also shown in Fig. 11 and 12. There is a need for a system or device for determining the angle (s) between the central axis of said first mouth 2 and the central axis of the second mouth 4.

In one embodiment of the manufacturing method of said superstructure, a superstructure is first manufactured in a way known to the skilled artisan, and then provided with a communication according to above. Such a method is for example disclosed in the Swedish patent SE 509,437, but other manufacturing methods known to the skilled artisan, such as moulding etc., are also within the scope of the present invention. In one embodiment of the present invention the superstructure is, in contrast to the manufacturing methods according to the prior art, manufactured with integrated spacer elements, milled from one single-piece blank, such that the dental superstructure obtains a main body and spacer elements, wherein said main body and said spacer elements are integrated. In this context the term integrated means that the dental superstructure, comprising a main body, and the spacer elements are consisting of one piece of material, such that no interface is present in between said superstructure and said spacer elements. In this superstructure the dimensions of spacer elements can be varied in accordance with the specific dental situation of a patient intended to receive said replacement structure. When the superstructure is applied the spacer elements will be cooperating with dental implants, inserted and osseointegrated in bone tissue. To obtain a perfect fit, i.e. no gap, between the superstructure and the gum tissue, the length and angle, in respect of the jawbone, superstructure, and jawbone, of the spacer elements will be individual for each spacer in respective spacer position.

In one embodiment the material of said superstructure may be selected from the group comprising titanium, zirconium oxide, alloys of titanium and zirconium, and other biocompatible materials, or combinations thereof.

When a superstructure, according to any of the embodiments above, has been obtained, a superstructure wherein a central axis of at least one part of a screw- channel differs from a central axis of a mouth of a screw member seat is provided. In one embodiment this is obtained, according to Fig. 2, by drilling a first straight bore 21 from a first point 22 on a side of the dental superstructure, at which first point 22 the mouth of the screw-channel is to be placed, and a second straight bore 23 from a second point 24 on the side of the dental superstructure intended to face the implant or spacer element. It is of course possible to drill the second bore 23 before the drilling of the first bore 21, while still being inside the scope of the present invention. The first and second bores are drilled such that they intersect in the interior of the dental superstructure. Then a third bore 31 may be drilled, according to Fig. 3, after the drilling of said first bore 21 and said second bore 23. This third bore may result in a screw-channel. This third bore may be drilled using said first and second bores as guides. Said third bore may be drilled by using a drill bit with a cutting surface of a sufficient diameter to create a bore through which a screw member may be passed in order to attach the dental superstructure to a spacer element or an implant 5. The third bore 31, i.e. the screw-channel 1, may preferably be drilled close to said second point 24, but not the whole way through. Since the diameter of the third bore 31 is larger than the diameter of said second bore 23, shoulders 32 will form in the screw-channel 1. Said shoulders may then form the seat 3 for a screw member head in the bottom of the screw-channel 1, while being integrated with said superstructure. Thus, a threaded part of a screw member inserted in the screw-channel may be passed through said bore, i.e. said second bore 23, to subsequently attach the dental superstructure to a spacer element or implant 5. Preferably, the diameter of said second bore 23 corresponds to the diameter of the threaded part of the screw member, whereby the screw member may be passed through said bore to fixate the superstructure to an implant or a spacer element 5. Thus, a dental superstructure comprising a main body, comprising a screw- channel 1 with a first mouth 2, through which screw-channel 1 a screw member is to be inserted, and a screw member seat 3 with a second mouth 4, for providing support to the head of said screw member during fixation of said dental superstructure to a spacer element or an implant 5 through said second mouth 4, may be obtained. Hereby a communication is obtained between said first mouth 2 and said second mouth 4. By providing a central axis of at least a part of said screw-channel 1 and a central axis of said second mouth 4 that do not coincide, one may guide the position of said first mouth 2, i.e. through which a screw member is to be inserted, into a position that optimizes the arrangement of the superstructure. This may for example be to locate said first mouth 2 in an aesthetically pleasing position, such as on a surface of the superstructure that can not be seen from outside the mouth of the patient. It is also possible that only the direction of the central axis of a part of the screw-channel 1 differs from the direction of the central axis of the mouth 4 of the screw member seat 3, in accordance with Fig. 1, while still being inside the scope of the present invention .

In one embodiment of the present invention the central axis of said first mouth 2 and the central axis of said second mouth 4 do not coincide.

In one embodiment the first bore 21 and the second bore 23 are made with a conventional twist drill. In this way the first bore 21 and the second bore 23 are drilled to a diameter of a suitable size for passing of the threaded part of a screw member, which screw member is used for attaching the superstructure to a spacer element or implant 5. It is also possible to drill said second bore 23 using a drill bit with a cutting surface of a sufficient diameter to create a bore through which a screw member may be passed in order to attach the dental superstructure to a spacer element or an implant.

In yet another embodiment of the present invention the superstructure is provided with a dental implant seat or a spacer element seat, such as a recess suitable for receiving a protrusion on said dental implant or spacer element. It is of course also possible to provide the superstructure with a protrusion and the dental implant or spacer element with a recess, as long as the seating effect is obtained. This dental implant seat or a spacer element seat provides the advantage of easier assembling of the superstructure on a dental implant or a spacer element.

Before a dental superstructure may be manufactured a dental technician and/or dental surgeon may build up a dental model based on the specific dental situation of a patient. A bite template of the patient mouth anatomy, made of e.g. wax, may be used for this purpose. The bite template is produce by placing a material, such as wax, in the mouth of the patient having dental implants, and letting the patient bite the material, and thus an exact reproduction of the patient specific dental status is obtained. The bite template thus contains information about the positions of the dental implants. The bite template may then be used to create a dental model of the specific patient. The dental technician and/or dental surgeon then refines the dental model in respect of bore angles etc., such that e.g. the mouth of a screw channel not is visible from outside the mouth of the patient. The final dental model thus reflects the desired final result. A difficulty of manufacturing the superstructure with a non-linear screw-channel has been to translate the dental model information, such as information regarding the bore angles to an apparatus with capability of manufacturing the superstructure. In order for the superstructure to perfectly match the dental model, the bore angles may be fixated in the dental model before the manufacturing of the superstructure proceeds.

In an embodiment a bore angle member, such as a bore angle screw, according to Fig. 4, is provided. This bore angle screw comprises a head portion 41, and a screw member portion 42. The head portion 41 may have a spherical or semi-spherical shape. In the top of the head portion 41, a screw recess 43 is provided, such that the screw member 42 of the bore angle screw may be screwed into e.g. a dental implant by means of a screwdriver having the corresponding inverted shape of the screw recess. In an embodiment the screw recess has the shape of a hexagon. Different sizes of the screw member 42 may of course be used without departing from the scope of the present invention. In an embodiment a bore angle connector 51, according to Fig. 5, is provided. The bore angle connector may have a bottom portion 52 that precisely fit the shape of the bore angle head portion 41. For example, if the bore angle screw head portion is spherical with a specific diameter, the bottom portion 52 may have the corresponding spherical diameter. Moreover the bore angle connector has a main portion 53. This main portion 53 may resemble the shape and size of the bore that will be made for each dental implant in the resulting manufactured superstructure. In another embodiment the bore angle connector bottom portion 52 is concavely shaped to receive the bore angle screw head portion 41, with the same diameter, however the bottom portion inlet area of the bore angle connector 52 is slightly smaller than the head portion 41 of bore angle screw. This means that the bore angle connector 52 may me pressed over the bore angle screw head portion 41, by expansion of the connector material, to become securely connected. This may for example be accomplished if the bore angle connector is manufactured of a resilient material, such as a plastic material. Thus, the bore angle screw may be mounted on an implant, in the mouth of a patient or in a mould corresponding to the dental situation of a patient. A bore angle connector may then be mounted, such as snapped onto, the bore angle screw. Then, the bore angle connector may be pivoted into a position that corresponds to a position of a first mouth 2 of the superstructure intended to be manufactured by the aid of the system, said system comprising said bore angle screw and said bore angle connector, such that said first mouth 2 will be located in a suitable position on said superstructure that will not be visible from the outside of a mouth of a patient. This angle may then be fixed and/or measured, and the manufacturer of the superstructure will know where to position said first and second mouth on said superstructure. Thereby, the angle between the bore angle screw and the bore angle connector will correspond to the angle between a central axis between said first mouth 2 and a second mouth 4, at a screw member seat 3. A suitable position will be a position possible on the dental system used in case referred to, whereby a suitable screw member seat will be formed in the screw channel.

In an embodiment the bore angle connector bottom portion 52 is slotted, such that the bottom portion 52 may be pressed over the head portion of the bore angle screw, to snap or click around the bore angle screw head portion, in order to become more fixated. This may for example be accomplished if the bore angle connector is manufactured of a resilient material, such as a plastic material.

When the bore angle connector 51 is connected or pressed on the bore angle screw head portion 41, it may be pivoted, such as rotated, in the same way as a ball joint, if the head portion 41 is of a spherical or semi-spherical shape. A degree of friction may be provided that makes interconnection between the bore angle connector bottom portion 52 and the screw head portion 41 suitable for remaining in one angle position, such that it requires a fair amount of force, e.g. applied by hand, to pivot, such as rotate, the bore angle connector 51 around the bore angle screw head 41. The friction coefficient may be varied using different materials of the bore angle connector 51, and the bore angle head portion 41.

In one embodiment the interconnection between the bore angle connector bottom portion 52 and the screw head portion 41 may be such that the bore angle connector may be rotated into such an angle that the screw recess 43 may be reached, i.e. that the bore angle connector bottom portion 52 does not cover the screw recess. In this way the bore angle head portion 41 and the bore angle connector bottom portion 52 may be interconnected during the obtainment of information regarding angles and positions.

In still one embodiment the bore angle head portion has a flat circular shape. The bore angle connector may in this embodiment have a corresponding bottom portion, e.g. such that the circular shape fits into a recess in the bottom portion of the bore angle connector. The recess may be angled such that the bore angle connector may only be rotated in the plane of the recess, and accordingly in the plane of the circular shape. In an embodiment the head portion of the bore angle screw is attachable/detachable from the bore angle screw. By utilizing this embodiment, various head portions of different shapes may be selected, having different shapes for reducing the degree of rotation from three dimensions to two dimensions or even one dimension. In a practical implementation the dental technician and or dental surgeon may first, attach the bore angle screw into the dental implant of the dental model. Subsequently, the attachable/detachable head portion is removed and is replaced by a new head portion. A bore angle connector having a bottom portion corresponding to the attachable/detachable head portion of the bore angle screw is then connected to the attached head portion. Using the attachable/detachable bore angle screw head portion and corresponding bore angle connector bottom portion will reduce the degree of rotation, and thus bore angle, to two or one dimensions. An advantage of this embodiment is that as the degree of rotation is reduced for the bore angle connectors, the final dental model will be more robust and insensitive to outer conditions that might influence the bore angles, e.g. unintended applied forces on the dental model during transport to the manufacturer that otherwise might have changed the bore angles of the dental model.

The shape of the head portion of the bore angle screw and the corresponding bore angle connector shape may be any shape providing a means for rotation of the bore angle connector in respect the bore angle screw.

In an embodiment, according to Fig. 6, the bore angle screw head portion 61 has the same shape as the bottom portion 52 of the bore angle connector according to Fig. 5. Thus, to be able to connect said screw head portion 61 with the bottom portion of the bore angle connector, the bore angle connector bottom portion 72 has the same shape as the head portion 41 of the bore angle screw according to Fig. 4. This is illustrated in Fig. 7.

In an embodiment, according to Fig. 8a, a distance member 80 is provided. The distance member 80 may in use be placed between the implant and bore angle screw head portion. In one embodiment, according to Fig. 8a, this distance member 80 is configured such that it circumferences the bore angle screw. This may for example be obtained by configure this distance member in the form of a ring. This ring may be threaded to fit with the threaded part of the screw member 42. In this way this distance member 80 may be screwed passed the threaded part of the screw member 42, to thereafter fit with the unthreaded part of the screw member 42. The function of the distance member 80 is to limit the angle of freedom of the bore angle connector 51 that is connected to the bore angle head portion 41. This limitation is enabled, as the bore angle connector at a certain angle, with reference to the bore angle screw length, will contact the distance member making it impossible to achieve a greater angle between the bore angle screw and the bore angle connector. In an embodiment, according to Fig 8b, the distance member 80 may be placed between the head portion of the bore angle screw and the dental implant without the need of being screwed through the threaded part of the bore angle screw. The design of distance member may be suitable for attaching the distance member around the main portion of the bore angle screw. By attaching is meant that the distance member 80, e.g. in the form of a ring having at least the same diameter as the main body of the bore angle screw, and provided with an opening 81. The opening 81 enables the distance member to be pushed around the bore angle screw main portion, i.e the part of the bore angle screw being located between the head portion 41 and the screw member portion 42.

In respect of Figs. 6 and 7, the distance member may instead be placed on, or integrated with, the bore angle connector, to thereby provide the limitation of freedom of the pivoting of the bore angle connector in respect of the bore angle screw.

Fig. 9a and 9b illustrates two setups of said distance member for limiting the angle of freedom of the bore angle connector 91. In Fig. 7a a distance member 92a with a height x is provided around a bore angle screw 93, which is screwed into a dental implant 94. The bore angle connector 91 is attached to the bore angle screw head portion 95. The possible angle between the bore angle connector and the bore angle screw, as the distance member is placed between the dental implant and the bore angle screw is indicated as y. In Fig. 7b a distance member 92b with the height 2x is provided between the head portion and dental implant. This corresponds to a maximal angle of z. As may be observed from Figs. 9a and 9b, by increasing the height of the distance member the possible angle between the connector and the bore angle screw is decreased, and vice versa. In an embodiment the centre of the head portion of the bore screw angle determines the position of the screw member seat in the superstructure. In this way a sufficient distance is created from the screw member seat, such as the screw member seat 3, and the second mouth, such as the second mouth 4, of the screw channel 1, to provide a fixating effect when a screw member is screwed through said second mouth into a dental implant or a spacer element.

In an embodiment the distance member corresponds to the maximum bore angle for the dental system used. There are several dental systems commercially available, each utilizing different dental implants etc. The distance member hence determines a specific maximum bore angle for each dental system and/or dental implant. In this way a dental technician and/or a dentist may apply distance members on the unthreaded part of the screw member 42, which distance members certifies that the maximum angle of the chosen dental system not is exceeded.

It is also possible to integrate a distance member on the unthreaded part of the screw member 42. Thus, a set of screw members 42 may only be used when a dental system accepting screw channel angles lesser than the angle that may be obtained by the interaction between the bore angle screw, comprising a head portion, such as a head portion 41, and an integrated distance member, and a screw member portion, such as a screw member portion 42, and a bore angle connector, such as a bore angle connector 51, when the bore angle connecter is angled until the bottom portion, such as the bottom portion 52, reaches, and thereby stops at, the distance member 80. In a practical implementation, the dental technician and/or dental surgeon provides the dental model implants with one bore angle screw each. Then a bore angle connector is connected to each bore angle screw. The dental technician and/or dental surgeon then modify the desired bore angle for each implant by rotating the bore angle connector into a desired angle. When the dental technician and /or dental surgeon is satisfied with the bore angle orientation a distance member according to an embodiment may be positioned between each bore angle screw head portion and the dental implant. By adjusting the height of the distance member, the desired angle may be achieved with high precision. After a distance member, giving the desired angle between the bore angle connector and the bore angle screw, is placed between the head portion and the bore angle connector, the connector is fixated to the dental implant, e.g. by means of fixating wax, plastic, tape, glue or any other fixating means. In this manner the remaining dental implants of the model is processed. The end result will be a dental model having bore angle connectors with fixated angles to the dental implant length axis for each dental implant that requires bores with an angle. The dental model may then be sent to a manufacturer for manufacturing a superstructure for the patient specific dental model.

Throughout the dental modelling, made by the dental technician and/or dental surgeon, the distance between the bore angle screw head and the dental implant will be fix as the bore angle screw has the same length and will be screwed into the implant completely.

In an embodiment, according to Fig. 10a and 10b, a cylindrical cavity 101 is provided within the bore angle connector 51, extending from the end of the main portion 53 towards the end of the bottom portion 52. The cylindrical cavity 101 may be located in the centre of the bore angle connector 102 as indicated in Fig. 10a and Fig 10b. In Fig 10a the cylindrical cavity extends from the end of the main portion 53 towards the bottom portion end 52, with a length smaller than the total bore angle connector length. In Fig. 10b the cylindrical cavity extends throughout the total bore angel connector. The cylindrical cavity may be used to precisely determine the position and angle of the bores in the manufacturing of the final superstructure.

In an embodiment the cylindrical cavity of the bore angle connector, e.g. each bore angle connector of the refined dental model as mentioned above, is provided with an extended structure, such as a cylindrical structure fitting in the cylindrical cavity. To precisely determine the bore angle in three dimensions as well as the exact position of each dental implant, a photo scanner may be used to image the dental model. The information regarding the bore angles and the implant positions are then used in manufacturing the superstructure.

In an embodiment the extended structure has a predetermined length and a predetermined end shape, such as a circular shape. In this way it only requires one image from one camera direction to obtain all bore angles and dental implant positions of the dental model. In this respect the Swedish patent application SE 0602116-6 is hereby integrated in its entirety herein as reference.

The dental model comprising the extended structure (s) may then be scanned with a photo scanner in three dimensions such that the bore angle and exact position of the dental implant may be obtained for the entire dental model. This may be performed by inserting a cylindrical or other structure fitting the cylindrical cavity of each bore angle connector and subsequently image the cylindrical structures to determine the exact bore angle for each dental implant of the dental model in three dimensions, as well as the position of the dental implant using the knowledge of the bore angle screw head portion location.

The different members of the present invention, i.e. the bore angle screw, the bore angle connector, and the distance member, may be manufactured of any suitable material or combinations of suitable materials. These materials may for example be metals, plastic materials etc. Such metals may for example be stainless steels, aluminum, titanium etc. It is thus possible to manufacture the bore angle screw of a suitable metal, such as a stainless steel, the bottom portion of the bore angle connector of a plastic material, the main portion of the bore angle connector of a metal, such as a stainless steel, and the distance member of a metal, such as a stainless steel. In an embodiment the bore angle screw is made of plastic material.

In another embodiment the bottom portion of the bore angle connector 52 is made of a suitable metal, such as stainless steel or aluminum.

In an embodiment a tooth set-up may be mounted on the system comprising the bore angle screw (s), the bore angle connector (s) , and the distance member (s). This mounting may be accomplished by fixating with wax or plastic material. Thereafter, the tooth set-up may be disconnected from said bore angle screw (s) by snapping of the connector (s) there from, while still being connected to said bore angle connector (s) . The angle or angles between said bore angle screw (s) and said bore angle connector (s) may be determined before or after the mounting of the tooth set-up on said system. When the tooth set-up with attached connector (s) has been disconnected from said bore angle screw (s), the tooth set-up with attached connector (s) may be sent to the dentist, dental surgeon, or dental technician. The tooth set-up with attached connectors may be sent to the dentist together with the bore angle screws, or the dentist, dental surgeon, or dental technician may have an own set of bore angle screws. Thereby, the dentist, dental surgeon, or dental technician may reconnect the tooth set-up with attached connector (s) to the bore angle screw (s), when the bore angle screw (s) have been attached to the dental implant (s), whereby the angles for the bore channels and the location of the mouths of the bore channels may be provided to thereby manufacture a fitting superstructure.

Depending on the type of dental implant and dental status of the patient, the final bore angles may vary in the dental model, created by the dental technician and/or dental surgeon.

The application of the tooth set-up may be performed both before and after the refinement of the bore angle, made by the dental technician and/or dental surgeon. In an embodiment the bore angle of each implant may be refined in correspondence with the applied tooth set-up, giving a specific bore angle for each dental implant. Hence, in this embodiment the bore angle may differ for each dental implants of the dental model. In another embodiment the dental technician and/or dental surgeon applies, and refines the tooth set-up based on the maximum bore angle for each implant of the dental model. In this embodiment the bore angle may differ for each dental implant of the dental model. Hence, in this embodiment the bore angle is maximal for each dental implant in reference to the bore angle screw.

In yet another embodiment a combination of specifically set bore angles and the maximum bore angles for each implant may be used to precisely apply the tooth set-up.

The present invention provides solutions that facilitates in the dental modeling and the manufacturing of a dental superstructure.

Advantages of the present invention are various. Using the invention according to some embodiments, the dental model of the specific patient is facilitated and the end result is easier to predict, e.g. by using a tooth setup in conjunction with the bore angle screw and bore angle screw connector. Moreover, using the present invention according to some embodiments, the bore angles and position of the implants may be exactly reproduced in the manufactured dental superstructure, and hence the present invention solves the problem of converting the bore angles defined by the dental technician and /or dental surgeon precisely to be able to create a dental superstructure.

The elements and components of an embodiment of the invention may be physically, functionally and logically implemented in any suitable way. Indeed, the functionality may be implemented in a single unit, in a plurality of units or as part of other functional units. As such, the invention may be implemented in a single unit, or may be physically and functionally distributed between different units and processors.

In an embodiment a graphical user interface is provided. The graphical user interface may be used as a computerized dental modeling tool by the dental surgeon or dental technician. The graphical user interface may be provided with a number of windows, each representing e.g. an observation plane, or 3D model. The graphical user interface is configured to enable virtual 3D dental modeling and is capable of creating or optionally retrieving a virtual dental model comprising the jaw structure of the patient. Optionally, if the dental implants are already attached to the patient jaw structure, also their respective position may be comprised in the virtual model. The virtual dental model may be acquired using a photo scanner as mentioned above or in any other known technique 3D scanning. By 3D scanning is meant acquiring a set of 2D images followed by performing image analysis to be able to create a 3D model. In some embodiments the graphical user interface is configured to create a 3D dental model of a set of acquired 2D dental images. Once the 3D dental model is acquired and loaded into the graphical user interface, the user is able to virtually attach bore angle screws, distance members, bore angle connectors to each of the dental implants comprised in the virtual dental model. Moreover, the user may interactively change each of the bore angles of each dental implant in a suitable way, e.g. by using a pointing device, such as a mouse or keyboard. This may optionally be performed in each of three perpendicular planes or in a visualized 3D model directly. In some embodiments the graphical user interface comprises Computer Aided Design (CAD) or Computer Aided Manufacturing (CAM) software to facilitate modification of the virtual dental model and for manufacturing of the final, finalized virtual dental model. In some embodiments the bore angles may be defined statically using the keyboard by setting the desired degree values using any suitable coordinate system, such as Cartesian coordinates, polar coordinates, etc. In some embodiments the graphical user interface is configured to generate a virtual superstructure based on the user-defined components, such as bore angles, of the dental implant. Thus, during generation of the superstructure parameters such as bore angle, dental implant position, is taken into account by the superstructure generating code segment. In some embodiments a "generate superstructure" button is provided in at least one window of the graphical user interface to generate the superstructure. In some embodiments the virtual superstructure may be provided with a virtual teeth row. This particularly advantageous as it enables the dental surgeon or dental technician to observe the final result virtually and to be able to re-modify the dental model until a perfect fit is achieved. Once the user dental surgeon or dental technician is satisfied with the virtual dental model, a detailed specification of the virtual superstructure may be printed out. Optionally, by using incorporated CAM software, an exact true model of the virtual superstructure may be manufactured. This provides for a cheap and effective way of creating a superstructure to a dental model.

Thus, according to one embodiment of the present invention, a virtual dental system for determining a suitable angle for a dental superstructure with a non- linear screw-channel is provided, said system comprising a virtual bore angle member, comprising a head portion, said bore angle member being configured to be mounted on a dental implant, and a virtual bore angle connector having a bottom portion for connection to said head portion of said bore angle member, whereby said bore angle member and said bore angle connector are pivotably connected to each other, wherein said virtual dental system, virtual bore angle member, and virtual bore angle connector are configured to be used in a computerized dental modeling software. It is also possible to provide this virtual dental system with a virtual distance member, according to above, limiting the freedom of angle between said virtual bore angle member and said virtual bore angle connector.

Although the present invention has been described above with reference to specific illustrative embodiments, it is not intended to be limited to the specific form set forth herein. Rather, the invention is limited only by the accompanying claims and other embodiments than the specific above are equally possible within the scope of these appended claims.

In the claims, the term "comprises/comprising" does not exclude the presence of other elements or steps. Furthermore, although individually listed, a plurality of means, elements or method steps may be implemented by e.g. a single unit or processor. Additionally, although individual features may be included in different claims, these may possibly advantageously be combined, and the inclusion in different claims does not imply that a combination of features is not feasible and/or advantageous. In addition, singular references do not exclude a plurality. The terms "a", "an", "first", "second' etc do not preclude a plurality. Reference signs in the claims are provided merely as a clarifying example and shall not be construed as limiting the scope of the claims in any way.

Claims

1. A dental system for determining a suitable angle for a dental superstructure with a non-linear screw- channel, said system comprising a bore angle member, comprising a head portion (41, 61), said bore angle member being configured to be mounted on a dental implant, and a bore angle connector (51, 71) having a bottom portion (52, 72) for connection to said head portion (41, 61) of said bore angle member, whereby said bore angle member and said bore angle connector (51, 71) are pivotably connected to each other.

2. The dental system according to claim 1, comprising a distance member (80) limiting the freedom of angle between said bore angle member and said bore angle connector (51, 71).

3. The dental system according to claim 2, wherein said distance member (80) is an open or closed ring with a height corresponding to a maximum angle between said bore angle member and said bore angle connector (51, 71) .

4. The dental system according to claim 2 or 3, wherein said distance member (80) is located on said bore angle member or said bore angle connector (71) .

5. The dental system according to claim 4, wherein said distance member (80) is integrated with said bore angle member or bore angle connector (71) .

6. The dental system according to claim 1, wherein said head portion (41) has a spherical or semi-spherical shape, and said bottom portion (52) is adapted for receiving said spherical or semi-spherical head portion (41), or said bottom portion (72) has a spherical or semi- spherical shape, and said head portion (61) is adapted for receiving said spherical or semi-spherical bottom portion (72) .

7. The dental system according to claim 1, wherein said bottom portion (52) of said bore angle connector or said head portion (61) of said bore angle member is of a resilient material.

8. The dental system according to claim 7, wherein said resilient material is a plastic material.

9. The dental system according to claim 1, wherein the bottom portion of the bore angle connector is slotted, such that said bottom portion may be pressed over said head portion of said bore angle member.

10. The dental system according to any of the preceding claims, wherein said dental system is a virtual dental system, configured to be used in a computerized dental modeling software.

11. A bore angle member, configured to be mounted on a dental implant, said bore angle member comprising a head portion (41, 61) configured to be pivotably connected to a bore angle connector.

12. The bore angle member according to claim 11, wherein said bore angle member is a virtual bore angle member, configured to be used in a computerized dental modeling software.

13. A bore angle connector, comprising a main portion (53) and a bottom portion (52, 72), said bottom portion being configured to be pivotably connected to a bore angle member .

14. The bore angle connector according to claim 13, comprising a cylindrical cavity (101) extending from the end of the main portion (53) towards the end of the bottom portion (52, 72) .

15. The bore angle connector according to claim 13 or 14, wherein said bore angle connector is a virtual bore angle connector, configured to be used in a computerized dental modeling software.

16. A distance member (80), configured to be connected to a bore angle member or a bore angle connector (51, 71), such that the pivoting angle between said bore angle member and said bore angle connector is limited.

17. The distance member according to claim 16, wherein said distance member is a virtual distance member, configured to be used in a computerized dental modeling software .