Kit for determining the position of features, such as a dental implant, within the mouth of a patient

Abstract

A kit (10) for determining the position of features within a patient's mouth is disclosed, comprising a scan body (20, 20', 20'') having fixation means for connection to an artificial or a biological feature, a reference structure (50, 50', 50'') detectable by a scanner, a connection structure (60, 60', 60''),and a plurality of arm members (30, 30', 30'') having a complementary connection structure (210, 210', 2100) having a configuration complementary to the connection structure (60, 60', 60'') to connect the connection structure (60, 60', 60'') and the complementary connection structure (210, 210', 2100). Each arm member (30, 30', 30'') comprises a matching connection structure (250, 250', 2500) having a configuration equivalent to the connection structure (60, 60', 60''), such that the matching connection structure (250, 250', 2500) on one arm member can be connected to the complementary connection structure (210, 210', 2100) of another arm member.

Description

[0001]Kit for determining the position of features, such as a dental implant, within the mouth of a patient The present invention relates to a kit for determining the position of features within the mouth of a patient, in particular for determining the position of a dental implant within the mouth of a patient. When designing a prosthesis to replace a tooth or teeth, it is necessary to obtain an accurate model of the patient's mouth. Traditionally this has been achieved using a plaster cast. While effective, this process is uncomfortable for the patient, requires numerous materials, time and has high material costs. However, more recently scanning equipment has been developed which enables a digital model of the patient's mouth to be created. When building a digital model of the mouth, components known as scan bodies are attached to fixed objects in the mouth, e.g. a tooth or dental implant. These scan bodies have a geometry known to the scanning software and act as reference points within the mouth, around which a digital model can be built. When scanning a mouth which contains little or no teeth (this latter situation being known as edentulous), large spaces of relatively “featureless” gingiva exist between the scan body reference points. This leads to mismatching of the images obtained during scanning, resulting in an unreliable digital model. A23901WO / 01.11.2024 / To address this problem, photogrammetry equipment can be used. However, such systems are expensive as they require special multicamera systems. US10080636 describes such a system. A more affordable alternative is the use of scan bodies comprising one or more arms extending radially from the longitudinal axis of the scan body. The arms from adjacent scan bodies can be positioned to contact one another, or other objects in the mouth. The arms of the scan bodies can thus provide a continuous reference surface for the scanner along the surface of the jaw and thus enable an accurate stitching together of the images obtained. Several such scan body systems currently exist. In particular, WO2023 / 081956 discloses a device and a method for determining the position of a dental implant within the mouth of a patient. The at least one device comprises a central body with an attachment portion adapted to attach to a dental implant in the jaw of a patient, and a separate collar from which one or more arms extend away. Several collar types are provided, having different numbers, lengths and orientations of arms. The desired collar can be connected to the central body before the at least one device is attached to the dental implant such that the one or more arms extend radially outwards from the central body. The one or more arms are adapted to bond to at least one other central body or arm of another device. In use, the dental practitioner couples a central body with the desired collar to a dental implant. The practitioner repeats this step for each dental implant, choosing suitable collars such that at least one arm or central body of each device can bond with another device. The practitioner then bonds the devices together using a bonding material such as a composite A23901WO / 01.11.2024 resin. A scan of the bonded devices as well as the surrounding visible gum is obtained using an intraoral scanner. WO2022 / 094301 and WO2021 / 087549 disclose further such scan body systems. In each case, a kit of scan bodies is provided, each scan body having a radially extending arm that can be placed in contact with, e.g. another scan body or other structure within the mouth. These existing scan body systems provide a fixed number of arm geometries which are either integral with or can be connected to a central scan body. Such systems therefore require a variety of arm designs to be produced and the dentist must use the fixed number of component shapes available to provide a continuous scan body reference surface over the area of the mouth which it is desired to scan. This can be difficult, particularly when only limited features exist within the mouth to which scan bodies can be fastened, for example when only two implants are available on which the scan bodies can be fastened. It is an object of the present invention to provide for a scan body system allowing the determination of the position of features, such as a dental implant, within the mouth of a patient with a good accuracy over a large portion of featureless gingiva, the system comprising a limited number of versatile components. The problem is solved by a kit for determining the position of features within the mouth of a patient according to claim 1. Preferred embodiments are disclosed in the dependent claims. A23901WO / 01.11.2024 The invention relates to a kit for determining the position of features within the mouth of a patient, the kit comprising at least one scan body and a plurality of arm members. The at least one scan body extends along a body longitudinal axis from an apical end to a coronal end, said scan body comprising fixation means for connection to an artificial or a biological feature in the mouth of a patient. In addition, the scan body comprises a reference structure that enables the position and orientation of the at least one scan body to be detected by a scanner. An artificial feature can be for example a dental implant component. The dental implant component can be for example an implant or an abutment. When the fixation means is for connection to a dental implant component, the kit is for determining the position of a dental implant within the mouth of a patient. An artificial feature can alternatively be a component, such as a fiducial marker, which is temporarily placed in the patient’s mouth at a position remote from the implant site and which is removed again after the dental work is complete. A biological feature can be, for example, a tooth, the bone or the gum. When the fixation means is for connection to a feature other than a dental implant component, whether the feature is artificial or biological, the kit is suitable for determining the position of a dental implant within the mouth of the patient and / or for determining the location of various other features within the mouth of the patient. In particular, such a kit can be used to gain an accurate image of the patient's mouth prior to implant placement. A23901WO / 01.11.2024 The scan body further comprises at least one connection structure for the connection of an arm member. Each arm member extends from a first end to a second end along an arm longitudinal axis and comprises at least one complementary connection structure having a configuration complementary to the at least one connection structure of the scan body, such that the at least one connection structure and the at least one complementary connection structure can be connected together. According to the invention, each arm member further comprises at least one matching connection structure having a configuration equivalent to the at least one connection structure of the scan body, such that the at least one matching connection structure on one arm member can be connected to the at least one complementary connection structure of another arm member. The presence of the at least one complementary connection structure on each arm member and the at least one connection structure on the at least one scan body allows the assembly of the arm members with the scan body. In this way at least one of the plurality of arm members can be attached to the scan body. Starting from this primary assembly, the presence of the at least one matching connection structure on each arm member allows the connection of a further arm member to the arm member of the primary assembly. This is achieved by connecting the at least one complementary connection structure of the further arm member to the at least one matching connection structure of the arm member of the primary assembly. This connection is A23901WO / 01.11.2024 possible because the configuration of the at least one matching connection structure of the arm members is equivalent to the at least one connection structure of the scan body, meaning that the complementary connection structure of an arm member can be connected to either a connection structure or a matching connection structure. Still further arm members can be connected to the assembly, if necessary, to form, in an assembled state, a scan assembly extending from the artificial or biological feature, for example a dental implant component, to another fixed structure in the mouth, for example a tooth or a further dental implant component. The kit of the present invention therefore allows a scan assembly to be built up which extends from the artificial or the biological feature, for example a dental implant component, in any direction and orientation desired by the operator, for a distance that can also be determined by the operator. By providing a plurality of arm members that can be attached not just to the scan body but also to each other, the flexibility of the system can be increased without requiring an increasing number of differently shaped components, which would increase the complexity and expense of the system. In accordance with conventional dental terminology, “apical” refers to the direction towards the bone and “coronal” to the direction towards the occlusal surface of the teeth. Therefore, the apical end of a component is the end which, in use, is directed towards or into the jawbone and the coronal end is that which is directed towards or into the oral cavity. In the following passages, different features of the invention are defined in more detail. Each feature so defined may be A23901WO / 01.11.2024 combined with any other feature or features unless clearly indicated to the contrary. In particular, any feature indicated as being preferred or advantageous may be combined with any other feature or features indicated as being preferred or advantageous. According to the present invention the arm members each comprise at least one complementary connection structure having a configuration complementary to the at least one connection structure of the at least one scan body. In the context of the present invention, a structure having a configuration complementary to a further structure is to be understood such that the surfaces of the structure and of the further structure are dimensioned such that the surfaces can interact with one another in order to connect the components together. Preferably the at least one connection structure and the at least one complementary connection structure are configured such that they can be connected together in a form fitting manner, for example by friction fit, interference fit, press fit, snap fit etc. In such embodiments one of the at least one connection structure and the at least one complementary connection structure typically comprises an internal surface while the other of the at least one connection structure and the at least one complementary connection structure comprises an external surface that is sized and shaped to be accommodated and held within the internal surface. According to the present invention the arm members each comprise at least one matching connection structure having a A23901WO / 01.11.2024 configuration equivalent to the at least one connection structure of the at least one scan body. In the context of the present invention, a structure having a configuration equivalent to a further structure is to be understood such that the surfaces of the structure and further structure are dimensioned such that they can both independently interact with a single complementary structure in order to connect to this structure. In the present case this allows the at least one complementary connection structure to be connected to either a matching connection structure or to a connection structure. In the preferred embodiment described above, in which the at least one connection structure and the at least one complementary connection structure are configured such that they can be connected together in a form fitting manner, the at least one matching connection structure is preferably also configured to connect to the at least one complementary connection structure in a form fitting manner. In such embodiments the at least one matching connection structure typically has the same internal / external orientation as the at least one connection structure. In other words, when the at least one connection structure comprises an internal surface the at least one matching connection structure also comprises an internal surface, whereas when the at least one connection structure comprises an external surface the at least one matching connection structure also comprises an external surface. While a structure having an equivalent configuration to a further structure does not need to be identical to the further A23901WO / 01.11.2024 structure, for design simplicity and consistency, it is often preferred to use identical configurations. In a preferred embodiment therefore, each arm member comprises at least one matching connection structure having a configuration identical to the at least one connection structure of the at least one scan body. This embodiment can be designed and manufactured in a simple manner. In one embodiment, the at least one connection structure of the scan body and the at least one matching connection structure of each arm member comprise an external surface, e.g. a pin, a protrusion, or another external part of the at least one scan body and plurality of arm members respectively. In this embodiment the at least one complementary connection structure of each arm member comprises an internal surface, e.g. a passage, an aperture or another internal part of each arm member, wherein the external surfaces of the at least one connection structure and the at least one matching connection structure are dimensioned to be accommodated and held within the internal surface of the complementary connection structure. In a preferred embodiment however, the at least one connection structure of the scan body and the at least one matching connection structure of each arm member comprise an internal surface, e.g. a passage, an aperture, or another internal part of the at least one scan body and arm member respectively. Further, the at least one complementary connection structure of each arm member comprises an external surface, e.g. a pin, a protrusion, or another external part of each arm member, wherein the external surface of the at least one complementary connection structure is dimensioned to be accommodated and A23901WO / 01.11.2024 held within the internal surface of both the at least one connection structure and the at least one matching connection structure. Both of these embodiments have the advantage that the scan body and the arm members can be assembled together by inserting the corresponding external surface into the internal surface, which provides a simple connection method. Forming the at least one connection structure as an internal surface has the additional advantage of minimizing the height and footprint of the scan body. In addition, many scan bodies are connected to the artificial or biological feature, in particular a dental implant component, via a screw, and thus comprise a screw channel. When the at least one connection structure is an internal surface, this can be formed out of the existing screw channel, leading to efficiencies in design. Preferably the structure(s) of the plurality of arm members which comprise an internal surface, i.e. either the at least one matching connection structure or the at least one complementary connection structure, form through holes in the arm member. This enables the form fitting external surface to be inserted into the internal surface from one of two opposing directions, thus increasing the versatility of the kit. In particularly preferred embodiments the at least one connection structure, the at least one matching connection structure and the at least one complementary connection structure each have a circular cross-section. Such a construction enables the arm members to be rotated with respect to each other and the scan body. This feature provides the user with fully flexible positioning of the arm members. A23901WO / 01.11.2024 According to an alternative preferred embodiment, the at least one connection structure, the at least one matching connection structure and the at least one complementary connection structure each have a non-circular-symmetric cross-section. For example, the structures may have a polygonal cross-section, such as hexagonal or octagonal, or they may comprise a number of radially extending lobes, forming e.g. a hexalobular cross- section. Such shapes allow locking of a relative rotational position of an arm member with respect to a scan body or another arm member in an assembled state. Throughout this specification, unless stated otherwise, a “cross-section” refers to the cross-section of an object in a plane perpendicular to the longitudinal axis of the object. In either of the above embodiments, the at least one connection structure, the at least one matching connection structure and the at least one complementary connection structure can have the form of a truncated cone, this cone having either a circular or non-circular base. Preferably however, the at least one connection structure, the at least one matching connection structure and the at least one complementary connection structure each comprise a substantially cylindrical surface. This arrangement further simplifies the design and the production of the scan body and the arm members. Cylindrical surfaces also increase the ease of connection and disconnection of the components, which allows both a precise and flexible positioning of the arm members when assembling the dental device. The term “substantially” covers precisely cylindrical shapes as well as those with small taper angles of up to 5° in the longitudinal direction of the A23901WO / 01.11.2024 surface. Such small taper angles may be present due to the production method used, e.g. injection moulding, or manufacturing tolerances. Including a very slight inward taper on the structure(s) comprising an external surface can also ease insertion of the structure into the internal surface while also allowing these structures to form a good friction fit. Therefore, according to one preferred embodiment, at least one of the at least one connection structure, the at least one matching connection structure and the at least one complementary connection structure comprises a substantially cylindrical external surface having a taper angle of less than 5° and at least another of the at least one connection structure, the at least one matching connection structure and the at least one complementary connection structure comprises a substantially cylindrical internal surface with a taper angle less than the substantially cylindrical external surface. For example, the external surface may have a taper angle of between 1-3° while the internal surface has no taper angle. For the remainder of this specification, references to “cylindrical” surfaces should be interpreted as referring to “substantially cylindrical” surfaces, namely surfaces having a taper angle of between 0-5° relative to the longitudinal axis of the surface. In a particularly preferred embodiment, the at least one connection structure, the at least one matching connection structure and the at least one complementary connection structure each comprise a circular cylindrical surface. For example, in one preferred embodiment the at least one connection structure and the at least one matching connection A23901WO / 01.11.2024 structure are both circular cylindrical passages, while the at least one complementary connection structure is a circular cylindrical pin dimensioned to be accommodated and held within the passages. Alternatively, the at least one complementary connection structure is a circular cylindrical passage, while the at least one connection structure and the at least one matching connection structure are both circular cylindrical pins dimensioned to be accommodated and held within the passage. In both of these embodiments the circular cylindrical pin(s) are dimensioned to be connected to the circular cylindrical passage(s) in a form fitting manner. The circular cross- sections of the structures allow the pin(s) to be inserted into the passage(s) in any angular orientation. As discussed above, according to the present invention the at least one matching connection structure has a configuration equivalent to the at least one connection structure. In certain preferred embodiments, for design simplicity, the at least one matching connection structure has a configuration identical to the at least one connection structure. In such cases, the cross-section of the at least one matching connection structure will be the same as the cross-section of the at least one connection structure. However, it is also possible for the at least one connection structure and the at least one matching connection structure to have different cross-sections while still being equivalent. For example, the at least one connection structure of the scan- body may take the form of a passage having a circular cross- section, while the at least one matching connection structure A23901WO / 01.11.2024 may take the form of a passage having a hexagonal cross- section. Both structures can be configured to connect to a complementary connection structure in the form of a pin having a hexagonal cross-section. In such embodiments the hexagonal cross-sections of the complementary connection structure and the matching connection structure will have substantially the same size while the connection structure will have a radius equal to the radial length of the vertices of the hexagonal pin. In this way the vertices of the hexagonal pin will contact the circular wall of the passage and thus the complementary connection structure will be held within the connection structure. Such equivalent yet non-identical configurations enable the at least one connection structure and the at least one matching connection structure to connect in different manners to the same complementary connection structure, e.g. rotationally fixed or freely rotatable. In accordance with one embodiment therefore at least one of the at least one connection structure, the at least one complementary connection structure and the at least one matching connection structure comprises a circular cross- section and another of the at least one connection structure, the at least one complementary connection structure and the at least one matching connection structure comprises a non- circular symmetric cross-section. In embodiments in which the at least one connection structure, the at least one complementary connection structure and the at least one matching connection structure each comprise a substantially cylindrical surface, it is preferred that the cross-sectional shape, e.g. circular, polygonal, etc of each A23901WO / 01.11.2024 structure remains constant along the length of the substantially cylindrical surface. However, in alternative embodiments it is possible for either both the at least one connection structure and at least one matching connection structure, or the at least one complementary connection structure, to comprise a first substantially cylindrical surface having a proximal section with a circular cross-section and a distal section with a non- circular-symmetric cross-section. The first substantially cylindrical surface can be either an external surface, forming e.g. a pin, or an internal surface forming e.g. a passage. In the present context the “proximal” section of a structure is the end which in use will interact first with a cooperating structure while the “distal” section will interact with the cooperating structure only after the proximal section. Thus, the terms “distal” and “proximal” are defined with reference to the cooperating structure. In such an embodiment the other of either both the at least one connection structure and at least one matching connection structure, or the at least one complementary connection structure can comprise a second substantially cylindrical surface having a non-circular- symmetric cross-section equal to the cross-section of the distal section of the first substantially cylindrical surface. The cylindrical surfaces are dimensioned such that both the distal and proximal sections of the first substantially cylindrical surface can engage in a form fitting manner with the second substantially cylindrical surface. Such a construction enables an arm member to be connected to the scan body and / or a further arm member in either a rotationally fixed or rotationally free configuration. This A23901WO / 01.11.2024 enables the user to build up a scan assembly while the arm members are rotationally free before locking the arm members in position once the desired orientation has been achieved. For example, the at least one complementary connection structure can comprise a substantially cylindrical pin having a proximal section with a circular cross-section and a distal section having a polygonal cross-section, the radius of the circular cross-section being substantially equal to the minimum radial length of the polygonal cross-section. The at least one connection structure and at least one matching connection structure can comprise a substantially cylindrical passage having a polygonal cross-section equal to the cross- section of the distal section of the pin. When the proximal section of the pin is inserted into the passage, the circular nature of the proximal section will allow relative rotation between the components. However, if the pin is pushed further into the passage, such that the distal section is inserted, the angular orientation of the components becomes fixed. A similar effect can be achieved by providing a passage having a proximal circular cylindrical section and a distal polygonal section, the radius of the circular cylindrical section being substantially equal to the maximum radial length of the polygon, and a cylindrical pin having a polygonal cross-section substantially equal to the distal section of the passage. According to the present invention, each arm member comprises at least one complementary connection structure having a configuration complementary to the at least one connection structure of the scan body, such that the at least one connection structure and the at least one complementary connection structure can be connected together. In a preferred A23901WO / 01.11.2024 embodiment, each arm member comprises a complementary connection structure at its first end. This embodiment allows the connection of the arm member to a scan body or further arm member at its first end, thus ensuring that the full length of the arm member can extend away from the scan body or further arm member to maximise the length of the dental assembly. Additionally, when multiple arm members are connected to a scan body, positioning a complementary connection structure at the first end, as opposed to, e.g. the middle of the arm member, results in an arm member that requires limited space in the vicinity the scan body. As a result, where appropriate, multiple arm members can be attached to the scan body without contacting or interfering with each other. According to the present invention, the plurality of arm members each comprise at least one complementary connection structure and at least one matching connection structure. In a preferred embodiment, the at least one complementary connection structure and the at least one matching connection structure extend in a direction perpendicular to the arm longitudinal axis. In other words, the longitudinal axes of the at least one complementary connection structure and the at least one matching connection structure are perpendicular to the arm longitudinal axis. Additionally or alternatively, the at least one complementary connection structure and the at least one matching connection structure of each arm member preferably extend in the same direction. In other words, the longitudinal axes of the at least one complementary connection structure and the at least one matching connection structure are parallel to one another. A23901WO / 01.11.2024 Further, these axes preferably lie in a plane which contains the arm longitudinal axis. While, according to the present invention, it is possible for each arm member to comprise only a single complementary connection structure and a single matching connection structure, in a preferred embodiment each arm member comprises a plurality of complementary connection structures and / or a plurality of matching connection structures. This enables the arm members to be attached to the scan body and / or to one another at a plurality of locations along the arm member. This embodiment also enables multiple arm members to be connected to a single arm member. In embodiments in which each arm member comprises a plurality of complementary connection structures and / or a plurality of matching connection structures it is preferred that each complementary connection structure and matching connection structure has one or more of the preferred features described above. When an arm member comprises a plurality of complementary and / or matching connection structures these may have different shapes to one another. For example, one or more matching connection structure may have a circular cross-section while one or more further matching connection structure may comprise a non-circular-symmetric cross-section. For ease of manufacturing and maximal interoperability of the system however, it is preferable that each arm member comprises a plurality of identical complementary connection structures and / or a plurality of identical matching connection structures. Preferably, each and every complementary A23901WO / 01.11.2024 connection structure on each arm member is identical to one another and each and every matching connection structure on each arm is identical to one another. In a particularly preferred embodiment, each arm member comprises a single complementary connection structure and a plurality of, preferably identical, matching connection structures. This embodiment is particularly beneficial when the at least one connection structure and matching connection structures comprise an internal surface, while the single complementary connection structure comprises an external surface, as this reduces the volume and hence material cost of each arm member. Preferably, the single complementary connection structure is arranged at the first end of the arm member. Preferably, the plurality of matching connection structures and / or the plurality of complementary connection structures are spaced, preferably equally spaced, from one another along the arm longitudinal axis. In a particularly preferred embodiment, each arm member comprises a single complementary connection structure comprising an external surface, preferably having a circular cross-section, and a plurality of matching connection structures each comprising an internal surface, preferably having a circular cross-section, the complementary connection structure and plurality of matching connection structures extending along longitudinal axes that are parallel to one another and perpendicular to the arm longitudinal axis, the axes lying in a plane that contains the arm longitudinal axis. Most preferably the complementary connection structure and A23901WO / 01.11.2024 plurality of matching connection structures are substantially cylindrical. In a preferred embodiment, each arm member comprises a stop member which extends perpendicular to the arm longitudinal axis. The stop member is used to limit the angular displacement of a further arm member that is connected to the arm member. In other words, the stop member limits the rotational freedom of the plurality of arm members relative to one another when connected together. This can be beneficial for guiding the construction of the scan assembly. In a particularly preferred embodiment, the stop member is located at the first end of the arm member. When the arm member comprises a single complementary connection structure comprising an external surface extending perpendicular to the arm longitudinal axis, it is preferable that the stop member extends in the opposite direction to the complementary connection structure. According to the present invention the at least one scan body extends along a body longitudinal axis from an apical end to a coronal end and comprises at least one connection structure. In preferred embodiments a connection structure is located at the coronal end of the scan body and extends co-axial to the body longitudinal axis. Preferably this connection structure comprises an internal, preferably circular cylindrical, surface extending from the coronal surface of the scan body. In other embodiments, if the diameter of the scan body is sufficient, two or more connection structures may be located at the coronal end of the scan body and may extend parallel to the body longitudinal axis. Alternatively or additionally to A23901WO / 01.11.2024 either embodiment, at least one connection structure may extend in a direction perpendicular to the body longitudinal axis. In a preferred embodiment, the at least one scan body comprises a main body extending along the body longitudinal axis from the apical end to the coronal end, the main body comprising the fixation means and reference structure, the scan body further comprising at least one strut extending radially outwards from the main body. Preferably at least one connection structure is located on said strut. This allows the scan body to comprise multiple connection structures without increasing the overall diameter of the scan body, or requiring the connection structures to be too close together, which could cause complications for the connection of arm members. In addition, this embodiment allows an arm member to be connected to the scan body at a distance remote to the reference structure, thus ensuring that the arm member does not obscure the reference structure from the scanner. When the at least one connection structure located on the at least one strut comprises an internal surface, it is preferable that this at least one connection structure forms a through hole in the strut. This enables the complementary connection structure to be inserted into the internal surface from one of two opposing directions, thus increasing the versatility of the kit. In one particularly preferred embodiment the at least one scan body comprises a connection structure located at the coronal end of the main body which extends co-axial to the body longitudinal axis and at least one strut extending radially outwards from the main body, the at least one strut comprising A23901WO / 01.11.2024 at least one connection structure which preferably extends parallel to the body longitudinal axis. This allows the connection of more than one arm member to the scan body in the same axial orientation. Preferably, the at least one strut extends in a direction perpendicular to the body longitudinal axis to allow the construction of the dental assembly in a plane extending perpendicular to the body longitudinal axis. In a preferred embodiment, the main body and the at least one strut are separate parts designed to be attached together. The parts can be assembled by press fit, snap fit or any known assembly mechanism. In case there is little space in the mouth of the patient, the scan body can be used without the strut which increases the versatility of the kit. When the main body and the at least one strut are separate parts, the at least one strut and the main body can each comprise a linking surface complementary to each other to allow attachment in a form-fitting manner. It is noted that the at least one strut can alternatively or additionally be fixed to the main body by an adhesive agent. In a preferred embodiment, the complementary linking surfaces are formed by an attachment portion on the at least one strut that is clipped onto a receiving portion of the main body, preferably in a clipping direction extending perpendicular to the body longitudinal axis. In a preferred embodiment, the at least one scan body comprises a plurality of struts, each strut extending radially outwards from the main body and being angularly offset from one another, at least one connection structure being located on each strut. This embodiment increases the number of arm members that can A23901WO / 01.11.2024 be attached to the scan body. As already discussed, at least one, preferably all struts of the plurality of struts, can be formed as separate parts that are designed to be assembled with the main body by way of complementary linking surfaces. While the main body and the at least one strut can be formed as separate parts, in other preferred embodiments the at least one strut is integrally formed with the main body. This results in a simplified system for the user. Such an integral scan body is particularly advantageous when the at least one scan body comprises a single strut. However, it is also possible for a plurality of struts to be integrally formed with the main body. While the one or more strut of the at least one scan body can comprise a plurality of connection structures, it is preferred that each of the one or more strut of the scan body comprises a single connection structure. This limits the length of the strut(s) and also prevents connection structures from being placed too close together, which could cause complications for the connection of arm members. As described above, it is possible for the at least one scan body to comprise a plurality of connection structures, with these connection structures being located on the main body and / or one or more struts of the scan body. When a scan body comprises a plurality of connection structures these may have different shapes to one another. For example, one or more connection structure may comprise a surface having a circular cross-section while one or more further connection structure may comprise a surface having a non-circular-symmetric cross- section. For ease of manufacturing and maximal A23901WO / 01.11.2024 interoperability of the system however it is preferable that, when a scan body comprises a plurality of connection structures, the connection structures are all identical to one another. In a preferred embodiment of the kit of the present invention, the at least one connection structure of the at least one scan body comprises a surface, preferably an internal surface, extending along a longitudinal axis which is coaxial or parallel to the body longitudinal axis. In addition, the at least one matching connection structure of each arm member comprises a surface, preferably an internal surface, extending along a longitudinal axis which is perpendicular to the arm longitudinal axis. In addition, the at least one complementary connection structure of each arm member comprises a surface, preferably an external surface, extending along a longitudinal axis which is perpendicular to the arm longitudinal axis. In this embodiment, the scan body and the arm member can be connected in such a way that the arm longitudinal axis is perpendicular to the body longitudinal axis to allow the construction of the dental device starting from a direction extending perpendicular to the body longitudinal axis. In alternative embodiments, it is also possible that the at least one complementary connection structure and / or the at least one matching connection structure of each arm member extends along a longitudinal axis which is parallel or coaxial to the arm longitudinal axis, and / or for the at least one connection structure of the scan body to extend perpendicular to the body longitudinal axis. A23901WO / 01.11.2024 In a preferred embodiment, when an arm member is connected to the scan body, the at least one matching connection structure and the at least one complementary connection structure extend in a direction co-axial or parallel to the body longitudinal axis, or perpendicular to body longitudinal axis. When a plurality of matching connection structures and / or complementary connection structures are present on the arm member some may extend parallel to the body longitudinal axis while others extend perpendicular to body longitudinal axis. Preferably however, in the assembled state, all complementary and matching connection structures of the arm member extend parallel or coaxial to the body longitudinal axis. According to the present invention, the at least one scan body comprises a reference structure that enables the position and orientation of the at least one scan body to be detected by a scanner. This ensures that a precise location of the corresponding artificial feature, for example the dental implant component, or biological feature can be obtained, which is vital when creating the dental prosthetic. Preferably the reference structure is located at the coronal end of the scan body. The reference structure can be any known structure or combination of structures that enables the position and orientation of the scan body to be detected by a scanner. Many such reference structures are known in the art. In a preferred embodiment, the reference structure comprises at least one planar surface parallel to or angled obliquely relative to the body longitudinal axis. Preferably this surface extends from the coronal surface of the scan body. Such a reference structure allows a determination of the scan body position and A23901WO / 01.11.2024 orientation in a three-dimensional space while also being simple to design and produce. For maximum design simplicity the reference structure may comprise a single planar surface of the type described above. Other shapes of reference structure that allow a unique determination of the scan body position can also be used, for example a multi-faceted surface. Further, the reference structure can be a combination of surfaces that are located at different positions on the scan body to ensure that at least one of the surfaces can be detected by the scanner in the assembled state of the dental device. According to the present invention the at least one scan body comprises fixation means for connection to an artificial feature or biological feature in the mouth of the patient. Preferably the at least one scan body comprises fixation means for connection to an artificial feature, preferably a dental implant component. The dental implant component may be a dental implant, abutment, or any other component of a dental implant system that is fixedly placed in the mouth. Preferably the fixation means is arranged for connection to a dental abutment, most preferably an abutment designed for connection to a multiple tooth prosthesis, e.g. a full denture prosthesis. Alternatively, the fixation means can be arranged for connection to a dental implant. In alternative embodiments the fixation means is designed for connection to an artificial feature other than a dental implant component. The artificial feature may be, for example, a fiducial marker, which is temporarily placed in the patient’s mouth at a position remote from an implant site and is removed again after the dental work is complete. A23901WO / 01.11.2024 Any known fixation means can be used. Typically, the fixation means will comprise a cavity or protrusion at the apical end of the scan body which can be connected to a protrusion or cavity of the artificial feature, in particular of the dental implant component or fiducial marker. In some embodiments, this cavity or protrusion can comprise an indexing section to allow the scan body to be fixed to the artificial feature, for example the dental implant component or fiducial marker, in a fixed rotational position. Many such indexing sections are known in the art and usually comprise a section having non-circular symmetric cross-section. Additionally or alternatively the fixation means preferably comprises a through hole extending along the body longitudinal axis suitable for housing a fastening screw. This enables the scan body to be firmly fastened to the artificial feature, for example the dental implant component or fiducial marker. In such embodiments, the coronal part of the through hole may form a connection structure, in particular a connection structure having an internal circular cylindrical surface. Alternatively, the at least one scan body comprises fixation means for connection to a biological feature, such as a tooth, the bone or the gum. In such embodiments the fixation means may comprise a cavity or protrusion at the apical end of the scan body which can be connected to a protrusion or cavity of the biological feature. Additionally or alternatively the fixation means may comprise a through hole extending along the body longitudinal axis suitable for housing a fastening screw. This enables the scan A23901WO / 01.11.2024 body to be firmly fastened to the biological feature, for example the bone. In such embodiments, the coronal part of the through hole may form a connection structure, in particular a connection structure having an internal circular cylindrical surface. Additionally or alternatively the fixation means may comprise a bonding surface to which bonding material, such as cement, can be applied for connecting the scan body to the surface of the biological feature, e.g. a tooth or the gum. This surface may be textured with, e.g. grooves, ridges, depressions, dimples etc to improve the adhesion of the bonding material. The surface may, alternatively or additionally, be concavely curved to better fit to the outer surface of the biological feature. According to the present invention, the kit comprises at least one scan body. Preferably the kit comprises a plurality of scan bodies. Each of the plurality of scan bodies can have one or more of the preferred features listed above. The plurality of scan bodies may be different to one another. For example, some scan bodies may comprise one strut, while others comprise two or no struts. The at least one connection structure of the scan bodies may be different. For example, some scan bodies may comprise one or more connection structure having a surface with a circular cross-section while others may comprise one or more connection structure having a surface with a non-circular symmetric cross-section. Preferably however, the kit comprises a plurality of scan bodies, each of the scan bodies being identical to one another. A23901WO / 01.11.2024 According to the present invention the kit comprises a plurality of arm members. The plurality of arm members may come in a variety of shapes, for example, the length of the members may vary, or the shape, position, number and orientation of complementary connection structures and matching connection structures may vary. However, it is preferred that the plurality of arm members are identical to one another. This maintains the simplicity of the system. The at least one scan body and the plurality of arm members of the present invention can be made of any suitable material which can be easily and accurately detected by a scanner. A biocompatible polymer material, such as poly(methyl methacrylate) (PMMA), plastic or polyether ether ketone (PEEK) is preferred. Alternatively, the at least one scan body and / or arm members can be formed of metal such as titanium. In a particularly preferred embodiment, the at least one scan body is formed of a biocompatible metal, in particular titanium or titanium alloy, while the plurality of arm members are formed of a polymer material. Creating the scan body from metal increases the strength of the body, which is beneficial particularly when the scan body is connected via a screw to the underlying feature, for example the dental implant component. A metal scan body is better able to withstand the torque applied to this. Creating the arm members from polymer makes these quicker and cheaper to produce. Preferably these arm members are manufactured by injection moulding. When a metal material is used the metal is preferably surface treated or coated to create a matt surface, such a surface being more easily detected by the scanner. For example, the A23901WO / 01.11.2024 components may have a sandblasted and / or acid etched external surface. Description of the figures Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Fig. 1 shows a perspective view of a first embodiment of a scan body included in a kit according to the invention for determining the position of a feature within the mouth of a patient, e.g. a dental implant; Fig. 2 shows a perspective view of a second embodiment of a scan body included in a kit according to the invention for determining the position of a feature within the mouth of a patient, e.g. a dental implant; Fig. 3 shows a perspective view of a first embodiment of an arm member which is part of a kit according to the invention for determining the position of a feature within the mouth of a patient, e.g. a dental implant; Fig. 4 shows a perspective view of a second embodiment of an arm member which is part of a kit according to the invention for determining the position of a feature within the mouth of a patient, e.g. a dental implant; Fig. 5 shows a perspective view of parts of a kit according to the invention in an assembled state for determining the position of a feature in the mouth of a patient, e.g. a dental A23901WO / 01.11.2024 implant, the kit comprising one scan body as represented in Fig. 1 and a plurality of arm members as represented either in Fig. 3 and Fig. 4; Fig. 6 shows a perspective view of a third embodiment of a scan body which is part of a kit according to the invention for determining the position of a feature within the mouth of a patient, e.g. a dental implant; Fig. 7 shows a perspective view of a third embodiment of an arm member which is part of a kit according to the invention for determining the position of a feature within the mouth of a patient, e.g. a dental implant; Fig. 8 shows a section cut through the scan body of Fig. 5, the scan body having fixation means for connection to a dental implant component; and Fig. 9 shows a section cut through the scan body in an alternative version of Fig. 5, the scan body having fixation means for connection to a biological feature. A kit 10 for determining the position of a feature within the mouth of a patient, e.g. a dental implant, according to a preferred embodiment of the invention comprises at least one scan body 20, 20’, 20’’’ and a plurality of arm members 30, 30’, 30’’’. A first embodiment of the at least one scan body 20 is represented in Fig. 1 and comprises a main body 40 extending along a body longitudinal axis 42 from an apical end 44 to a coronal end 46. Main body 40 is generally circular cylindrical, however other shapes are conceivable for the main body, for example a cylinder with a polygonal cross-section. A23901WO / 01.11.2024 The scan body 20 comprises fixation means at its apical end 44, for example in the form of a cavity, not visible in Fig. 1, for connection to a dental implant component. In addition, the fixation means includes a screw channel 45 extending along the body longitudinal axis 42 suitable for housing a fastening screw. Such fixation means are well known in the art. A suitable fixation means 43a for connection to a dental implant component is shown for example in Fig. 8. In alternative embodiments, the fixation means 43a can be for connection to a biological feature or an artificial feature other than a dental implant component. In some such embodiments the fixation means 43a may take the form of a bonding surface 49 at the apical end 44 of the scan body, see Fig. 9. The scan body 20 further comprises reference structure 50 in the form of a single planar surface angled obliquely relative to the body longitudinal axis 42. The reference structure 50 enables the detection of the position and orientation of the at least one scan body 20 by a scanner. The planar surface of the reference structure 50 is located at the coronal end 46 of the scan body 20 and extends from the coronal surface 47 of the scan body 20. The scan body 20 further comprises a strut 70 which extends radially outwards from the main body 40 in a direction perpendicular to the body longitudinal axis 42. In the embodiment of Fig. 1 the strut 70 is integrally formed with the main body 40. The scan body 20 further comprises connection structures 60 for connection of one or more arm member to the scan body 20. One connection structure 60a is located at the coronal end 46 A23901WO / 01.11.2024 of the main body 40 and extends co-axially to the body longitudinal axis 42 from the coronal surface 47 of the scan body 20. A further connection structure 60b is located on strut 70 and extends parallel to the body longitudinal axis 42. The connection structures 60a, 60b are identical to one another and each comprise a circular cylindrical internal surface 61. The circular cylindrical internal surfaces 61 may have a taper angle of between 0-5° relative to the longitudinal axis of the surface. Connection structure 60b forms a through passage in the strut 70. Connection structure 60a forms the coronal part of through hole 45, although in other embodiments this may be a blind bore. The connection structures 60 are designed to allow the connection of arm members to the scan body, as will be described below. The scan body 20’ represented in Fig. 2 is formed generally in the same manner as the scan body 20 already discussed in relation to Fig. 1. Same features are referred to by like reference numbers and are not discussed further. In contrast to the previous embodiment of Fig. 1, the main body 40’ and the strut 70’ of the embodiment disclosed in Fig. 2 are formed as separate parts that are designed to be attached together. For this purpose, the strut 70’ and the main body 40’ each comprise a linking surface complementary to each other to allow attachment in a form-fitting manner. In a concrete manner, the main body 40’ comprises a linking surface formed as a receiving portion 90, the receiving portion 90 having lateral walls 90a, 90b connected to each other by a convexly curved front wall 90c. The lateral walls 90a and 90b are formed by planar surfaces extending parallel to the body A23901WO / 01.11.2024 longitudinal axis 42. The strut 70’ comprises a linking surface in the form of an attachment portion 100 having planar lateral walls 100a, 100b connected by a concavely curved rear wall 100c. The attachment portion 100 can be clipped onto the receiving portion 90 in a clipping direction perpendicular to the body longitudinal axis 42’. The planar walls 90a, 90b, 100a, 100b ensure that the strut 70’ is attached to the main body 40’ in a rotationally fixed orientation. In other embodiments however, the separate strut may be rotatable relative to the main body. In a similar manner to reference structure 50, reference structure 50’ of Fig. 2 is located at the coronal end 46’ of the scan body 20’ and extends from the coronal surface 47’ of the scan body 20’. However, in this embodiment reference structure 50’ comprises a single planar surface parallel to the body longitudinal axis 42’. The reference structure 50’ enables the detection of the position and orientation of the at least one scan body 20’ by a scanner. Connection structures 60’ of scan body 20’ are identical to the connection structures 60 of Fig. 1. In particular, the connection structures 60a’, 60b’ are identical to one another and to connection structures 60a and 60b. Fig. 3 represents a first embodiment of an arm member 30 that is part of a kit 10 according to the present invention. Arm member 30 is designed to be used with the scan bodies 20, 20’ illustrated in Fig. 1 and Fig. 2. The arm member 30 extends from a first end 200 to a second end 203 along an arm longitudinal axis 202. The arm member 30 A23901WO / 01.11.2024 comprises a single complementary connection structure 210 arranged at the first end 200 of the arm member 30. The arm member 30 further comprises a plurality of matching connection structures 250 equally spaced from one another along the arm longitudinal axis 202. The complementary connection structure 210 has a configuration complementary to the connection structures 60, 60’ of the scan body 20, 20’ such that the complementary connection structure 210 can be connected to a connection structure 60, 60’ in a form fitting manner. To this end the complementary connection structure 210 comprises an external circular cylindrical surface 210a forming a pin dimensioned to be accommodated and held within internal circular cylindrical surfaces 61, 61’ of connection structures 60, 60’. The circular cylindrical surface 210a may have a taper angle of between 0-5° relative to the longitudinal axis 212 of the surface. The circular nature of the complementary connection structure 210 enables the arm member 30 to be rotated with respect to the scan body 20, 20’ when connected to this. The circular cylindrical external surface 210a extends along a longitudinal axis 212 that is perpendicular to the arm longitudinal axis 202. Matching connection structures 250 each have a configuration identical to the connection structures 60, 60’ of the scan body 20, 20’. Thus, each of the matching connection structures 250 comprises an internal circular cylindrical surface 251 having the same diameter as internal circular cylindrical A23901WO / 01.11.2024 surfaces 61, 61’. As a result, the complementary connection structure 210 of a further arm member 30 can be connected to any of the matching connection structures 250 in the same form fitting manner as it could to the connection structures 60, 60’ of the scan body 20, 20’. By providing a plurality of arm members 30 that can be attached not just to the scan body 20, 20’ but also to each other, a scan assembly can be built up which extends from the dental implant component, or other feature, in any direction and orientation desired by the operator, for a distance that can also be determined by the operator. This will be described later in relation to Fig. 5. The plurality of matching connection structures 250 each extend in a direction perpendicular to the arm longitudinal axis 202 and in the same direction. In other words, the longitudinal axes 252 of the plurality of matching connection structures 250 are parallel to one another. In addition, these axes 252 lie in a plane which contains the arm longitudinal axis 202 and, in the embodiment of Fig. 3, also the longitudinal axis 212 of the complementary connection structure 210. In other embodiments however, the longitudinal axes 252 of the matching connection structures 250 may lie in a plane perpendicular to the longitudinal axis 212 of the complementary connection structure 210. The arm member 30’ represented in Fig. 4 is formed generally in the same manner as the arm member 30 already discussed in relation to Fig. 3. This embodiment is also designed to be used with the scan bodies 20, 20’ illustrated in Fig. 1 and A23901WO / 01.11.2024 Fig. 2. Same features are referred to by like reference numbers and are not discussed further. In contrast to the previous embodiment of Fig. 3, the arm member 30’ comprises a stop member 260 which is located at the first end 200’ of the arm member 30’. The stop member 260 extends perpendicular to the arm longitudinal axis 202’ in the opposite direction to the complementary connection structure 210. The stop member 260 is used to limit the angular displacement of a further arm member that is connected to the arm member 30’. In other words, the stop member 260 limits the rotational freedom of the plurality of arm members relative to one another when connected together. In the present embodiment the stop member 260 is formed as cylinder having a tear drop shaped cross-section, the tapered part 261 of the cylinder extending towards the second end 203’ of the arm member 30’. As described above, the complementary configuration of the connection structures 60, 60’ and complementary connection structure 210, 210’ enables an arm member 30, 30’ to be attached to a scan body 20, 20’. Further, the equivalent configuration of the matching connection structures 250, 250’ allows the complementary connection structure 210, 210’ of one arm member 30, 30’ to be connected to a matching connection structure 250, 250’ of another arm member 30, 30’. As a consequence, a kit 10 according to the present invention allows a scan assembly to be constructed, as demonstrated in Fig. 5. The assembly of Fig. 5 comprises one scan body 20 according to the embodiment of Fig. 1, first 320, second 330 and third 340 arm members 30 according to the embodiment of A23901WO / 01.11.2024 Fig. 3 and one arm member 30’ according to the embodiment of Fig. 4. The complementary connection structure 210 of first arm member 320 is connected to the connection structure 60a of scan body 20, while arm member 30’ is connected to connection structure 60b of strut 70 via its complementary connection structure 210’. The plurality of connection structures 60 of scan body 20 allow the scan assembly to extend from the scan body 20 in multiple directions. The scan assembly is further extended through the connection of second 330 and third 340 arm members 30 to arm member 30’. The second arm member 330 is connected by way of its complementary connection structure 210 to the middle matching connection structure 250’ of the arm member 30’. Further, the third arm member 320 is connected to the same arm member 30’ by way of attachment of its complementary connection structure 210 to the matching connection structure 250’ at the second end 203’ of the arm member 30’. As the matching connection structures 250’ of this embodiment form through passages through the arm member 30’, arm members 330, 340 can be connected to the arm member 30’ from opposite sides. In this embodiment, the scan body 20 and the arm members 30’, 320, 330, 340 are connected in such a way that the arm longitudinal axes 202, 202’ are perpendicular to the body longitudinal axis 42 to allow the construction of the dental device extending perpendicular to the body longitudinal axis 42. This is due to the orientation of the connection structures 60, the complementary connection structures 210, A23901WO / 01.11.2024 210’ and matching connection structures 250, 250’ described above. The kit 10 of the present invention allows a user extreme flexibility in creating a scan assembly individualised for the specific situation of each patient. After the scan bodies 20, 20’ and arm members 30, 30’ have been assembled as desired these can be bonded together to fix the relative position of all components before scanning. In addition, the scan assembly can comprise a second scan body 20, 20’ connected to a further artificial or biological feature, such as a dental implant component, with arm members 30, 30’ connected to this second scan body extending towards and contacting arm members 30, 30’ attached to the first scan body. A further embodiment of a scan body 20’’ in accordance with the present invention is represented in Fig. 6 and a further arm member 30’’ in accordance with the present invention is represented in Fig. 7. The scan body 20’’ of Fig. 6 is configured generally in the same manner as the scan body 20 of Fig. 1. Same features are referred to by like reference numbers and are not described further. In contrast to scan body 20, 20’, the connection structures 600 of the scan body 20’’ comprise internal surfaces 610 having a non-circular symmetric cross-section, specifically a hexagonal cross-section. One connection structure 600a is located at the coronal end 46’’ of the main body 40’’ and extends co-axially to the body longitudinal axis 42’’ from the coronal surface 47’’ of the scan body 20’’. A further connection structure 600b is located on strut 70’’ and extends A23901WO / 01.11.2024 parallel to the body longitudinal axis 42’’. Connection structure 600b forms a through passage in the strut 70’’. Connection structure 600a forms the coronal part of through hole 45’’ extending along the main body axis 42’’ for housing a fastening screw. The connection structures 600 are designed to allow the connection of arm members to the scan body, as will be described below. The arm member 30’’ of Fig. 7 is configured generally in the same manner as the arm member 30 of Fig. 3. Same features are referred to by like reference numbers and are not described further. In contrast to arm member 30, 30’, the complementary connection structure 2100 comprises an external surface 2100a having a non-circular symmetric cross-section, specifically a hexagonal cross-section. The external surface 2100a therefore forms a pin, this pin being dimensioned to be accommodated and held within the internal surfaces 610. The complementary connection structure 2100 thus has a configuration complementary to the connection structures 600, of the scan body 20’’ such that the complementary connection structure 2100 can be connected to a connection structure 600 in a form fitting manner. The non-circular-symmetric nature of the complementary connection structure 2100 and connection structures 600 enables the arm member 30’’ to be locked in a relative rotational position with respect to the scan body 200’’ when connected to this. A23901WO / 01.11.2024 The arm member 30’’ further comprises a plurality of matching connection structures 2500 equally spaced from one another along the arm longitudinal axis 202’’. Matching connection structures 2500 each have a configuration identical to the connection structures 600 of the scan body 20’’. Thus, each of the matching connection structures 2500 comprises an internal surface 2510 having a hexagonal cross- section having the same size as internal cylindrical surfaces 610. As a result, the complementary connection structure 2100 of a further arm member 30’’ can be connected to any of the matching connection structures 2500 in the same form fitting manner as it could to the connection structures 610 of the scan body 20’’. A kit comprising a plurality of scan bodies 20’’ and arm members 30’’ as shown in Figs. 6 and 7 would create a kit in which the arm members 30’’ could only be connected to each other and to the scan bodies 30’’ in a rotationally locked manner. In other embodiments it would be possible to combine the non- circular-symmetric cross-sections shown in Figs. 6 and 7 with the circular cross-sections of Figs. 1-4, in order to create a kit that enables both rotationally fixed or rotationally free connections. In one such embodiment the connection structures 60, 60’ have a radius equal to the radial length of the vertices of the hexagonal cross-section of the complementary connection structure 2100. In this way, the vertices of the hexagonal pin will contact the circular wall of the passage and thus the complementary connection structure 2100 will be held within A23901WO / 01.11.2024 the connection structure 60, 60’. Arm member 30’’ could thus be connected in a rotationally free manner to scan bodies 20, 20’ and in a rotationally fixed manner to scan body 30’’. In an alternative embodiment the circular cylindrical surface 210a, 210a’ of complementary connection structure 210, 210’ could have a radius equal to the minimum radial length of the hexagonal cross-section of matching connection structures 2500 and connection structures 600. In this way, the complementary connection structure 210, 210’ could be held in a rotational manner within connection structures 600 or matching connection structures 2500. The kit of the present invention comprises at least one scan body that can be arranged for connection to either an artificial or a biological feature in the mouth of a patient. Fig. 8 shows the assembly of Fig. 5, wherein the scan body 20a comprises fixation means 43a for connection to a dental implant component. The fixation means 43a comprises a cavity 43 at the apical end 44 of the scan body 20a and a through hole forming a screw channel 45 extending along the body longitudinal axis 42 suitable for housing a fastening screw. It is noted that the scan body 20a is represented in a sectional view. Fig. 9 shows an alternative version of Fig. 5, wherein the scan body 20b comprises fixation means 43a for connection to a biological feature. Here the fixation means 43a comprises a concave bonding surface 49 at the apical end 44 of the scan body for glued attachment to, e.g. the gum. It is noted that the scan body 20b is represented in a sectional view. A23901WO / 01.11.2024 The above embodiments are described by way of example only and other variations are possible which fall within the scope of the claims. For example, the connection structures, complementary connection structures and matching connection structures could be tapered by an angle greater than 5°, thus forming truncated cones. The number and orientation of the connection structures, complementary connection structures and matching connection structures can vary, and vary between scan bodies and arm members within the same kit. List of reference numbers Kit 10 scan body 20, 20’, 20’’, 20a, 20b arm member 30, 30’, 30’’ main body 40, 40’, 40’’ body longitudinal axis 42, 42’, 42’’ fixation means 43a cavity 43 apical end of the scan body 44, 44’, 44’’ screw channel 45, 45’, 45’’ coronal end of the scan body 46, 46’, 46’’ coronal surface 47, 47’, 47’’ bonding surface 49 reference structure 50, 50’, 50’’ connection structure 60, 60’, 600, 60a, 60a’, 600a, 60b, 60b’, 600b internal surface 61, 61’, 610 strut 70, 70’, 70’’ receiving portion 90 A23901WO / 01.11.2024 lateral walls 90a, 90b front wall 90c attachment portion 100 lateral walls 100a, 100b rear wall 100c first end of arm member 200, 200’, 200’’ second end of arm member 203, 203, 203’’ arm longitudinal axis 202, 202’, 202’’ complementary connection structure 210, 210’, 2100 external surface 210a, 210a’, 2100 complementary connection structure longitudinal axis 212, 212’, 212’’ matching connection structure 250, 250’, 2500 internal surface 251, 251’, 2510 matching connection longitudinal axis 252, 252’, 2520 stop member 260 Tapered part 261 arm members of Fig. 3 320,330,340 A23901WO / 01.11.2024

Claims

Claims 1. Kit (10) for determining the position of features within the mouth of a patient, the kit comprising at least one scan body (20, 20’, 20’’) and a plurality of arm members (30, 30’, 30’’), the at least one scan body (20, 20’, 20’’) extending along a body longitudinal axis (42, 42’, 42’’) from an apical end (44, 44’, 44’’) to a coronal end (46, 46’, 46’’), said scan body comprising fixation means (43a) for connection to an artificial or a biological feature in the mouth of a patient and a reference structure (50, 50’, 50’’) that enables the position and orientation of the at least one scan body to be detected by a scanner, the scan body further comprising at least one connection structure (60, 60’, 600), each arm member (30, 30’, 30’’) extending from a first end (200, 200’, 200’’) to a second end (203, 203’, 203’’) along an arm longitudinal axis (202, 202’, 202’’) and comprising at least one complementary connection structure (210, 210’, 2100) having a configuration complementary to the at least one connection structure (60, 60’, 600) of the scan body (20, 20’, 20’’), such that the at least one connection structure (60, 60’, 60’’) and the at least one complementary connection structure (210, 210’, 2100) can be connected together, characterized in that each arm member (30, 30’, 30’’) further comprises at least one matching connection structure (250, 250’, 2500) having a configuration equivalent to the at least one connection structure (60, A23901WO / 01.11.202460’, 60’’) of the scan body, such that the at least one matching connection structure (250, 250’, 2500) on one arm member can be connected to the at least one complementary connection structure (210, 210’, 2100) of another arm member.

2. Kit (10) according to claim 1, characterized in that the at least one connection structure (60, 60’, 60’’) and the at least one complementary connection structure (210, 210’, 2100) are configured such that they can be connected together in a form fitting manner, and in that the at least one matching connection structure (250, 250’, 2500) is configured to connect to the at least one complementary connection structure in a form fitting manner.

3. Kit (10) according to claim 1 or 2, characterized in that each arm member (30, 30’, 30’’) comprises at least one matching connection structure (250, 250’, 2500) having a configuration identical to the at least one connection structure (60, 60’, 60’’) of the at least one scan body (20, 20’, 20’’).

4. Kit (10) according to claim 1, 2 or 3, characterized in that the at least one connection structure (60, 60’, 60’’) of the at least one scan body (20, 20’, 20’’) and the at least one matching connection structure (250, 250’, 2500) of each arm member (30, 30’, 30’’) comprise an internal surface (61, 61’, 610) and in that the at least one complementary connection structure (210, 210’,A23901WO / 01.11.2024(210a, 210a’, 2100a), wherein the external surface of the at least one complementary connection structure is dimensioned to be accommodated and held within the internal surface of both the at least one connection structure and the at least one matching connection structure.

5. Kit (10) according to any preceding claim, characterized in that the at least one connection structure (60, 60’, 60’’), the at least one matching connection structure (250, 250’, 2500) and the at least one complementary connection structure (210, 210’, 2100) each have circular cross-sections.

6. Kit (10) according to any preceding claim, characterized in that the at least one connection structure (60, 60’), the at least one matching connection structure (250, 250’) and the at least one complementary connection structure (210, 210’) each comprise a substantially cylindrical surface.

7. Kit (10) according to claim 6, characterized in that the cross-sectional shape of each structure remains constant along the length of the substantially cylindrical surface.

8. Kit (10) according to any preceding claim, characterized in that each arm member (30, 30’, 30’’) comprises a plurality of complementary connection structures (210, 210’, 2100) and / or a plurality of matching connection structures (250, 250’, 2500). A23901WO / 01.11.20249. Kit (10) according to any preceding claim, characterized in that each arm member (30, 30’, 30’’) comprises a single complementary connection structure (210, 210’, 2100) and a plurality of identical matching connection structures (250, 250’, 2500).

10. Kit (10) according to any preceding claim, characterized in that a connection structure (60, 60’, 60’’) is located at the coronal end (46, 46’, 46’’) of the at least one scan body (20, 20’, 20’’) and extends co-axial to the body longitudinal axis (42, 42’, 42’’).

11. Kit (10) according to any preceding claim, characterized in that the at least one scan body (20, 20’, 20’’) comprises a main body (40, 40’, 40’’) extending along the body longitudinal axis (42, 42’, 42’’) from the apical end (44, 44’, 44’’) to the coronal end (46, 46’, 46’’), the main body comprising said fixation means and reference structure (50, 50’, 50’’), the scan body further comprising at least one strut (70, 70’, 70’’) extending radially outwards from the main body, at least one connection structure (60, 60’, 60’’) being located on said strut.

12. Kit (10) according to claim 11, characterized in that the at least one strut (70, 70’, 70’’) is integrally formed with the main body (40, 40’, 40’’).

13. Kit (10) according to any preceding claim, characterized in that the kit comprises a plurality of scan bodies A23901WO / 01.11.2024(20, 20’, 20’’), each of the scan bodies being identical to one another.

14. Kit (10) according to any preceding claim, characterized in that the plurality of arm members (30, 30’, 30’’) are identical to one another.

15. Kit (10) according to any one of claims 1 to 14, characterized in that the at least one scan body (20, 20’, 20’’) comprises fixation means (43a) for connection to a dental implant component, the kit being suitable for determining the position of a dental implant within the mouth of a patient.

16. Kit (10) according to any one of claims 1 to 14, characterized in that the at least one scan body (20, 20’, 20’’) comprises fixation means (43a) for connection to a biological feature in the mouth of a patient. A23901WO / 01.11.2024

Images