WO2024175918A1

WO2024175918A1 - Dental abutment

Info

Publication number: WO2024175918A1
Application number: PCT/GB2024/050489
Authority: WO
Inventors: Tim DOSWELL
Original assignee: Harrogate Implant Innovations Ltd
Current assignee: Harrogate Implant Innovations Ltd
Priority date: 2023-02-22
Filing date: 2024-02-22
Publication date: 2024-08-29
Anticipated expiration: 2025-08-22
Also published as: GB202302539D0; EP4669265A1; GB2627467A; GB2627467B

Abstract

There is described a conometric abutment for use with a multi-unit abutment and a friction-fit dental prosthesis. The conometric abutment comprises a dental prosthesis attachment member operable to engage with a dental prosthesis to form a friction fit attachment to the prosthesis; and a multi-unit abutment attachment member operable to form an attachment to a multi-unit abutment. Also described is a kit of parts comprising a multi-unit abutment, and optionally a dental prosthesis and a dental implant.

Description

DENTAL ABUTMENT

FIELD

[01] The present invention relates to a conometric abutment for use with a multi-unit abutment. More specifically, the present invention relates to a prosthesis engaging conometric abutment for use with a multi-part abutment and a friction fit dental prosthesis.

BACKGROUND

[02] Dental prostheses, such as crowns, bridges and dentures, are commonly used to replace missing teeth. Such prostheses may be held in place in the mouth by one of several methods; connections with other teeth, connections to dental implants, by suction, or with passive holding by surrounding muscles.

[03] The use of dental implants normally involves inserting an implant into the bone of the jaw. As such, dental implants can be favoured because of the increased stability and conservation of natural tooth tissue that is provided compared to the other methods of attachment to the mouth.

[04] The dental prostheses can be directly attached to the dental implant(s), or via connectors such as press-stud style connections, bars or abutments, which act as an intermediate between the implant(s) and the prosthesis. Generally, the prosthesis attaches to the implant(s) via some form of abutment or bar.

[05] Conometric abutments can attach a dental prosthesis to dental implant by friction fit (i.e. there are no screws or cement involved). A patient would have the implants positioned in their mouth and a conometric abutment attached to each of these. The prosthesis is then retained on the conometric abutment via metal caps within the prosthesis, which fit intimately onto the abutments.

[06] The conometric abutment must be selected depending on a number of unique conditions. For example, the height of the conometric abutment must be selected depending on the patient’s gum thickness and the angle of offset of the conometric abutment must be selected depending on the position and location of the implant in the patient’s mouth. Typically, stock conometric abutments are used, however in order to facilitate a solution for each individual case taking into consideration the required height and angle, a large inventory of components is required to be maintained by the practitioner to ensure the best fit for a given case. Not only is this inefficient and costly for the practitioner, there is also a significant commercial cost for the manufacturer in producing these components.

[07] It is an object of aspects of the present invention to address one or more of the above mentioned, or other, problems.

SUMMARY [08] According to a first aspect of the present invention, there is provided a conometric abutment for use with a multi-unit abutment and a friction-fit dental prosthesis, wherein the conometric abutment comprises: i. a dental prosthesis attachment member operable to engage with a dental prosthesis to form a friction fit attachment to the prosthesis; and ii. a multi-unit abutment attachment member operable to form an attachment to a multiunit abutment.

[09] Advantageously, the present invention can provide a simple single size dental prosthesisengaging abutment that is operable to be used with other commonly used abutments, such as multi-unit abutments, to provide a means to enable such abutments to form a friction fit with the prosthesis. The single size abutment may take advantage of the height and angle adjustments of the multi-unit abutment while providing improved fit and hold with the prosthesis as well as allowing for improved efficiency of materials and fitting.

[10] The use of a single size abutment enables the practitioner to stock only one component that is suitable for use regardless of the patient’s gum thickness or position and location of the implant in the patient’s mouth, thereby improving efficiency and cost for both the practitioner and manufacturer.

[11] The dental prosthesis attachment member may have any suitable shape operable to form a friction fit attachment to the prosthesis. The dental prosthesis attachment member may have a conical external face, such as a conical frustum external face. The external face may taper at a gradient of at least 2°, such as at least 3°, such as at least 4°.

[12] The dental prosthesis attachment member may also be operable to engage with a dental cap such as to form an attachment with the dental cap.

[13] The dental prosthesis attachment member and the multi-unit abutment attachment member may each be aligned with the longitudinal axis of the conometric abutment, such as to be substantially opposed. The conometric abutment may be substantially linear, such as substantially straight.

[14] The dental prosthesis attachment member and/or multi-unit abutment attachment member may be integrally formed. The conometric abutment may be integrally formed.

[15] Advantageously, the conometric abutment may comprise a dental prosthesis engaging abutment member having a larger surface area for friction, for example because a screw access hole is not required on the side of the abutment, as they are for angled one-piece conometric abutments fitted at implant fixture level. Therefore, the area of contact of the friction between the dental prosthesis attachment member and the dental prosthesis may be higher, allowing for an improved friction fit. [16] The conometric abutment, dental prosthesis attachment member and/or multi-unit abutment attachment member may be formed of any suitable material, such as metal. The metal may comprise titanium, cobalt chromium, gold or gold alloy or any other appropriate material which develops friction on a metal abutment.

[17] The conometric abutment may be manufactured by any suitable process such as turning or milling. The conometric abutment may be manufactured by turning.

[18] Advantageously, as well as simplicity of production, manufacturing the conometric abutment by a turning process may improve the accuracy and reliability of the conometric abutment produced compared to a milling process. This may mean that the conometric abutment can provide improved reliability of friction fit with the dental prosthesis. By allowing for the use of a single size conometric abutment the present invention may enable the production of the conometric abutment of the present invention by turning to become economically viable.

[19] The improved accuracy of production may allow the conometric abutment of the present invention to provide a level of consistently high friction so that a removal mechanism is required to remove the prosthesis.

[20] According to a second aspect of the present invention, there is provided a kit of parts comprising: a. a conometric abutment according to the first aspect of the present invention; and b. a multi-unit abutment comprising:

I. a dental implant attachment member operable to engage with a dental implant to form an attachment to the dental implant; and

II. a conometric abutment attachment member operable to form an attachment to the conometric abutment, wherein the multi-unit abutment attachment member of the conometric abutment and the conometric abutment attachment member of the multi-unit abutment are operable to form an attachment.

[21] A multi-unit abutment may be operable to raise the prosthetic connection point of an implant to align with soft tissue, or to produce a level platform for the implant. An angled multi-unit abutment may also be used to correct the angulation of an implant, which may be beneficial to help avoid undesirable placement of screw access holes in the prosthesis.

[22] The conometric abutment attachment member may be aligned with the longitudinal axis of the multi-unit abutment/dental implant, such that the conometric abutment attachment member and the multi-unit abutment/dental implant are substantially opposed. The multi-unit abutment may be substantially linear, such as substantially straight multi-unit abutment. [23] The conometric abutment attachment member may be off-set from the longitudinal axis of the multi-unit abutment/dental implant. The multi-unit abutment may be an angled multi-unit abutment.

[24] The conometric abutment attachment member may be off-set by at least 5° relative to the longitudinal axis of the multi-unit abutment/dental implant, such as at least 10°, such as at least 15°, such as at least 20°. The conometric abutment attachment member may be off-set by up to 40° relative to the longitudinal axis of the multi-unit abutment/dental implant, such as up to 35° such as up to 30°.

[25] The angle of off-set of the conometric abutment attachment member relative to the longitudinal axis of the multi-unit abutment/dental implant may be selected depending on the position and location of the implant in the patient’s mouth.

[26] The multi-unit abutment may be operable to provide any suitable spacing height between the top of the implant and the bottom of the conometric abutment, such as any suitable gingival height. The multi-unit abutment may have a height of at least 1 mm, such as at least 1 .5 mm such as at least 2 mm. The multi-unit abutment have a height of up to 5 mm, such as up to 4.5 mm such as up to 3 mm.

[27] The height of the multi-unit abutment may be selected depending on the patient’s gum thickness and/or the angle of the dental implant in the jaw bone.

[28] The multi-unit abutment comprises a dental implant attachment member operable to engage with a dental implant to form an attachment to the dental implant. The multi-unit abutment may be operable to be reversibly attached to a dental implant. The multi-unit abutment may be operable to attach to a dental implant with a rotational attachment method, such as with complementary threads.

[29] The dental implant attachment member may comprise an aperture. The aperture may be operable to receive a fixing member, such as a screw, operable to fix the multi-unit abutment to a dental implant.

[30] The multi-unit abutment may comprise a bore extending substantially along the longitudinal axis of the multi-unit abutment, operable to allow for the passage of a fixing member, such as a screw, into the dental implant attachment member, such as into the aperture.

[31] The multi-unit abutment may be manufactured by any suitable process such as additive manufacturing, turning and/or milling. The multi-unit abutment may be manufactured by milling and/or turning.

[32] The multi-unit abutment may be a stock multi-unit abutment or a CAD/CAM multi-unit abutment. The multi-unit abutment may be a computer-assisted design/computer-assisted manufacturing (CAD/CAM) multi-unit abutment. [33] Advantageously, the combination of the conometric and multi-unit abutments of the present invention may provide for improved friction fit with a dental prosthesis in combination with improved simplicity of surgery through use of the multi-unit abutment to adapt for height and angle variations, which multi-unit abutment may be produced using a lower cost production method due to the wider tolerance range permitted for the multi-unit abutment.

[34] The multi-unit abutment attachment member of conometric abutment is operable to form an attachment to a multi-unit abutment. The multi-unit abutment attachment member of the conometric abutment may be operable to form an attachment with the conometric abutment attachment member of the multi-unit abutment.

[35] The multi-unit abutment attachment member of the conometric abutment may be operable to form a reversible attachment with a multi-unit abutment.

[36] The attachment of the conometric abutment with the multi-unit abutment may be a rotation attachment, such as with a cooperating threaded rotational attachment.

[37] The multi-unit abutment attachment member of the conometric abutment may comprise a female attachment portion and/or a male attachment portion. The male and/or female attachment portion may comprise a thread, such as a helical thread, operable to form a cooperating threaded attachment with a complimentary threaded portion on the multi-unit abutment.

[38] The multi-unit abutment attachment member may comprise an aperture. The aperture may be operable to receive a fixing member, such as a screw, operable to fix the conometric abutment to the multi-unit abutment.

[39] The conometric abutment may comprise a bore extending substantially along the longitudinal axis of the conometric abutment, operable to allow for the passage of a fixing member, such as a screw, into the multi-unit abutment attachment member, such as into the aperture.

[40] The female attachment portion and/or a male attachment portion of the multi-unit abutment attachment member may be integrally formed with the conometric abutment.

[41] The multi-unit abutment attachment member of the conometric abutment may comprise a male attachment portion, such as an integrally formed male attachment portion, wherein the male portion comprises a thread.

[42] The multi-unit abutment attachment member of conometric abutment may comprise a female attachment portion and a male attachment portion.

[43] The multi-unit abutment attachment member or the conometric abutment attachment member may comprise a female attachment portion and a male attachment portion, wherein the male attachment portion is arranged within the female attachment portion. The male attachment portion may comprise a thread, such as a helical thread, operable to form a cooperating threaded attachment with a complimentary threaded portion on the complementary attachment member. The female attachment portion may be substantially free of a thread. The female attachment portion may be operable to receive a male attachment portion of the complementary attachment member but may not be operable to form a direct attachment thereto.

[44] The dental prosthesis attachment member of the conometric abutment may comprise a tool engagement member operable to cooperate with a mating tool so as to provide leverage for the tool to actuate rotation of the conometric abutment, such as to actuate attachment or detachment of the conometric abutment to a multi-unit abutment. The tool engagement member may comprise a recess. The recess may be any suitable shape operable to engage with an external mating tool, such as, for example, a screw driver. The conometric abutment may comprise the tool engagement member on a top face of the dental prosthesis attachment member/conometric abutment.

[45] The conometric abutment attachment member of multi-unit abutment is operable to form an attachment to a conometric abutment. The conometric abutment attachment member of multiunit abutment may be operable to form an attachment to the multi-unit abutment attachment member of the conometric abutment.

[46] The conometric abutment attachment member of multi-unit abutment may be operable to operable to form a reversible attachment with a conometric abutment.

[47] The attachment of the multi-unit abutment with the conometric abutment may be a rotational attachment, such as with a cooperating threaded rotational attachment.

[48] The conometric abutment attachment member of the multi-unit abutment may comprise a female attachment portion and/or a male attachment portion. The male and/or female attachment portion may comprise a thread, such as a helical thread, operable to form a cooperating threaded attachment with a complimentary threaded portion on the conometric abutment.

[49] The female attachment portion and/or a male attachment portion of the conometric abutment attachment member may be integrally formed with the multi-unit abutment.

[50] The conometric abutment attachment member of the multi-unit abutment may comprise a female attachment portion wherein the female portion comprises a thread. The female attachment portion may be in communication with the aperture of the dental implant attachment member so that a fixing member is operable to pass through the female attachment portion to the aperture. The female attachment portion may comprise the upper end of the bore that is operable to allow for the passage of a fixing member.

[51] The conometric abutment attachment member of the multi-unit abutment may comprise a female attachment portion and a male attachment portion.

[52] The conometric abutment attachment member or the multi-unit abutment attachment member may comprise a male attachment portion and a female attachment portion, wherein the female attachment portion is arranged within the male attachment portion. The female attachment portion may comprise a thread, such as a helical thread, operable to form a cooperating threaded attachment with a complimentary threaded portion on the complementary attachment member. The male attachment portion may be substantially free of a thread. The male attachment portion may be operable to received by a female attachment portion of the complementary attachment member but may not be operable to form a direct attachment thereto.

[53] The kit of parts may further comprise: c. a dental prosthesis operable to form a friction fit attachment with the conometric abutment of the first aspect of the present invention, and/or dental cap operable to form an attachment with the conometric abutment of the first aspect of the present invention; and d. optionally, a dental implant.

[54] The dental prosthesis for forming a friction fit attachment to the conometric abutment of the first aspect of the present invention may comprise: a release device comprising a release member that is movable relative to the prosthesis from a first position to a second position; and wherein when the release member is in the first position the release device is not operable to impart a separating force to a friction fit attachment between the conometric abutment and the prosthesis and when the release member is in the second position the release device is operable to impart a separating force to a friction fit attachment between the conometric abutment and the prosthesis.

[55] Advantageously, when a seal has formed between the prosthesis and the conometric abutment that is too strong for removal of the prosthesis by the hand of the user alone, the user may simply actuate the release member of the release device to provide sufficient force to break the seal, enabling the prosthesis to thereafter be more easily removed from the conometric abutment by hand, all without requiring clinical intervention. The present invention therefore enables a prosthesis that has desirable aesthetics and sufficient stability whilst also permitting the user to maintain effective hygiene of the prosthesis, implant and conometric abutment without requiring further clinical assistance.

[56] According to a third aspect of the present invention there is provided a method for the release of a friction fit between a dental prosthesis and a conometric abutment according to any aspect of the present invention, the method comprising the steps of:

I. actuating the release member from the first position to the second position such that the prosthesis is released from the conometric abutment.

[57] The release device may be incorporated during the manufacture of the prosthesis or it may be retrofitted to an existing prosthesis. [58] According to a fourth aspect of the present invention there is provided a computer-readable medium having computer-executable instructions adapted to cause a 3D printer to print a release device, prosthesis, dental implant and/or conometric abutment according to any aspect of the present invention.

[59] The release device of the present invention is for arrangement in a dental prosthesis such that the device may actuate the release of a friction fit between the prosthesis and conometric abutment.

[60] The release device may have a width, depth and height each of up to 20mm, such as up to 15mm or up to 10mm. As such, the release device may have no dimension that is larger than the abovementioned sizes. It will be appreciated that an appropriate size for the release device is important in order to achieve the desired aesthetics and functionality of the dental prosthesis.

[61] The release device may comprise a housing.

[62] The housing of the release device may be formed of metal, preferably titanium. Suitably, the housing may be integrally formed or formed of separate components, preferably the housing is integrally formed.

[63] The outer face of the housing may comprise any suitable shape. The outer face of the housing may be substantially cylindrical.

[64] The outer face of the housing may comprise retention members operable to assist with retaining the release device in the prosthesis. The retention members may comprise one or more lugs, suitably a plurality of spaced lugs extending outwardly from the housing.

[65] Suitably, the release member comprises engagement means operable to cooperate with a mating tool such as to provide leverage for the actuation of the release member using the mating tool. Said engagement means may comprise a screw drive. The screw drive may be in any suitable shape that is operable to cooperate with the respective mating tool. Preferably, the screw drive is a hex-type screw drive.

[66] Any of the aspects of the present invention may further comprise a mating tool operable to actuate the release member from the first position to the second position and/or to actuate removal and/or attachment of a conometric abutment. Suitably, the mating tool is an angle corrected screw driver. Preferably, the mating tool comprises a release member/ conometric abutment engagement portion operable to cooperate with a screw drive on the release member. Suitably, the mating tool comprises an angled shaft extending between a handle portion and a release member engagement portion. Suitably, the shaft is angled at between 20° and 160°, such as between 40° and 140°, or 60° and 120°, or 80° and 100°, preferably the shaft is angled at substantially 90°.

[67] The release member may be moved from the first to the second position by translational and/or rotational movement, preferably by rotational movement. The release member may be formed of any suitable material. Suitably the release member is formed from metal, such as titanium.

[68] The housing and/or the prosthesis may be operable to hold the release member in the second position. By ‘hold’ it is meant that the housing and/or prosthesis is able to keep the release member in the second position for a period of time sufficient to allow the mechanical advantage generated by the movement of the release member to be exerted on the attachment between the prosthesis and the conometric abutment such as to release the attachment between the prosthesis and the conometric abutment.

[69] Suitably, the release device is operable to provide graduated levels of separating force. Preferably the housing or prosthesis is operable to hold the release member at more than one position in which a separating force is operable to be applied. For instance, the housing or prosthesis may be able to hold the release member at several different positions wherein each position allows the release device to impart a separating force between the prosthesis and the conometric abutment, and wherein the different positions provide different amounts of separating force. For example, the housing or prosthesis may be able to hold the release member in position 2a, 2b or 2c, wherein the amount of separating force applied by the release device increases from position 2a to position 2c. Suitably, the release member and the housing and/or prosthesis comprise cooperating helical threads. The graduated levels of force may be provided by the cooperating helical threads arranged on the release member and the housing or prosthesis. As such, the amount of feree applied for separating the prosthesis and the conometric abutment may be varied depending on the strength of the seal that has formed.

[70] Suitably, the release member of the release device of any aspect of the present invention is a captive release member within the housing and/or prosthesis. By “captive” it is meant that the release member cannot be removed from the housing and/or prosthesis without altering the respective housing, prosthesis and/or release member in a manner that allows for the release member to be removed. Preferably, the release member is captively held within a captive chamber in the housing.

[71] Preferably, the release member is removeably captive. The captive chamber of the housing may comprise a detachable wall such that detachment of the wall permits removal of the release member from the housing.

[72] Advantageously, providing a captive release member reduces the risk of a moveable part becoming separated from the device during use, improving the safety of the device. Further, if the captive release member is removable in a controlled manner then the user is able to better clean the device when necessary and/or replace the release member should it become damaged.

[73] The detachable wall may be a protective cap. Suitably, the protective cap forms the upper wall of the captive chamber. Optionally, the protective cap may form part of the side wall of the captive chamber and/or housing. The protective cap may comprise an aperture for providing access to the engagement means of the release member. Preferably, the protective cap extends across a portion of the upper face of the release member whilst the aperture provides access to the engagement means of the release member. As such, the protective cap may prevent the release member from escaping the captive chamber whilst also protecting some of the exposed faced of the release member. The protective cap may comprise a ridge extending around and above the upper face of the release member. As such, the protective cap may protect the prosthesis from damage during actuation of the release member with a mating tool through, for example, slippage of the mating tool. The outer face of the protective cap may be downwardly sloped towards the aperture or bevelled. The protective cap may be removeably attachable to the housing or prosthesis by any suitable means, such as cooperating helical threads arranged on the protective cap and the housing or prosthesis. The release member and the protective cap may be operable to form a close fit abutment around the aperture of the protective cap, such as to help prevent ingress of material into the device.

[74] Advantageously, a sloping outer face in the protective cap helps to guide the mating tool into the engagement means of the release member.

[75] The prosthesis may be a crown, bridge or denture. The prosthesis or prosthesis composition may be formed of a polymer, such as an acrylic polymer, for example polymethylmethacrylate (PMMA), or formed of composite resins or porcelains.

[76] The release device may be operable to be arranged or is arranged in the prosthesis such that it can be actuated on an occlusal surface of the prosthesis. Suitably, the release device is arranged in the prosthesis such that the release member may be actuated on an occlusal surface of the prosthesis. Optionally, the release device may be arranged remotely from an occlusal surface. For example, the release device may be operable to be arranged or is arranged in the prosthesis such that it can be actuated on a side surface of the prosthesis, preferably a buccal face. Advantageously, arranging the actuation point of the release member away from the occlusal surface of the prosthesis reduces the risk of food ingress into the release device and as such improves hygiene.

[77] The release member of the release device may be arranged or be operable to be arranged in the prosthesis such that in the second position the release member abuts the surface of the conometric abutment, suitably the outer face of the conometric abutment. Preferably, the release member is operable in the first position not to abut the surface of the conometric abutment. Should the abutment comprise a bore for receiving attachment means to connect the abutment to an implant, suitably the release member has a width that is greater than the width of the bore of the connector/abutment.

[78] The prosthesis may comprise an attachment chamber operable to receive and form a friction fit with a suitably sized conometric abutment. Suitably, the housing of the release device comprises an attachment chamber that is operable to receive the dental prosthesis attachment member of a conometric abutment and form a friction fit therewith.

[79] The attachment chamber of the housing or prosthesis may be tapered, suitably it is tapered such as to narrow upwardly from a widest point at an open end that is operable to receive the conometric abutment. Preferably, the chamber tapers at an angle of between 0.1° and 15°, such as between 1° and 10°, or between 2° and 8° or 3° and 7° or 4° and 6°. Preferably, the internal surface of the chamber is substantially smooth. Preferably the interior surface of the chamber is formed of metal, such as titanium or gold.

[80] The release member may be arranged above the attachment chamber, such as at an opposite end to the open end for receiving the conometric abutment. Preferably the release member is held captively above the attachment chamber.

[81] Suitably, the release member is operable to extend into the attachment chamber of the housing or prosthesis. Suitably, in the second position the release member extends further into the attachment chamber than in the first position.

[82] The release member may be operable to be moved from the first position to the second position by rotation of the release member, preferably, the release member is operable to rotate about an axis that is transverse to the longitudinal axis of the attachment chamber of the housing.

[83] The release member may comprise a cam, suitably the cam comprises a projection that makes contact with the abutment or implant in the second position to impart a separation force.

[84] Suitably, the release member is held within the housing such that rotation of the release member does not cause translational movement of the release member. Preferably, actuation of the separating force converts the rotational movement of the release member into translational movement of the prosthesis.

[85] When the conometric abutment is connected to the multi-unit abutment, and the conometric and multi-unit abutments are attached to the dental prosthesis and the dental implant, respectively, the conometric abutment may be operable to be arranged so that the dental prosthesis is off-set from the longitudinal axis of the multi-unit abutment/dental implant. The dental prosthesis may be off-set by at least 5° relative to the longitudinal axis of the multi-unit abutment/dental implant, such as at least 10°, such as at least 15°, such as at least 20°. The dental prosthesis may be off-set by up to 40° relative to the longitudinal axis of the multi-unit abutment/dental implant, such as up to 35° such as up to 30°.

[86] As used herein, the term ‘conometric abutment’ refers to an abutment that uses friction retention to hold a dental prosthesis and/or release device onto the abutment.

[87] As used herein, the term ‘substantially linear’ may mean at an angle of up to 5° off-set from the longitudinal axis, such as up to 3° or up to 1°. [88] As used herein, the term ‘substantially non-linear’ may mean at an angle of at least 6° offset from the longitudinal axis, such as 8° or 10°.

[89] Where used herein the phrase ‘separating force’ is intended to mean a force sufficient to loosen the attachment between the conometric abutment and the prosthesis to the extent that that an average user is then able to manually remove the prosthesis. It will be appreciated that the problem addressed by the present invention is that a seal can form between a dental prosthesis and a dental implant such that the prosthesis cannot be removed without clinical intervention. The present invention provides a device for releasing the seal between the prosthesis and the conometric abutment such that the prosthesis may be removed by the user without requiring clinical intervention.

[90] Singular encompasses plural and vice versa. For example, although reference is made herein to "a" conometric abutment, “a” multi-unit abutment, and the like, one or more of each of these and any other components can be used.

[91] The terms "comprising" and "comprises" as used herein are synonymous with "including", "includes" or "containing", "contains", and are inclusive or open-ended and do not exclude additional, non-recited members, elements or method steps.

[92] Additionally, although the present invention has been described in terms of “comprising”, the invention as detailed herein may also be described as “consisting essentially of’ or “consisting of’.

[93] As used herein, the term "and/or," when used in a list of two or more items, means that any one of the listed items can be employed by itself or any combination of two or more of the listed items can be employed. For example, if a list is described as comprising group A, B, and/or C, the list can comprise A alone; B alone; C alone; A and B in combination; A and C in combination, B and C in combination; or A, B, and C in combination.

[94] Where ranges are provided in relation to a genus, each range may also apply additionally and independently to any one or more of the listed species of that genus.

[95] Attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

[96] All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

[97] Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

[98] The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

[99] All of the features contained herein may be combined with any of the above aspects and in any combination.

BRIEF DESCRIPTION OF DRAWINGS

[100] The invention will now be described by way of example only and with reference to the accompanying drawings, in which:

[101] Figure 1 shows a side sectional view of a conometric abutment according to a first embodiment of the present invention. Figure 2 shows a side sectional view of a multi-unit abutment according to a second embodiment of the present invention.

[102] Figure 3 shows a side sectional view of a dental abutment comprising the conometric abutment shown in Figure 1 , the multi-unit abutment shown in Figure 2 and a dental implant.

[103] Figure 4 shows a side sectional view of a conometric abutment according to a second embodiment of the present invention. Figure 5 shows a side sectional view of a multi-unit abutment according to a second embodiment of the present invention.

[104] Figure 6 shows a side sectional view of a dental abutment comprising the conometric abutment shown in Figure 4, the multi-unit abutment shown in Figure 5 and a dental implant.

[105] Figure 7 shows a side view of the dental abutment and dental implant shown in Figure 6.

[106] Figure 8 shows a side view of the dental abutment and dental implant shown in Figure 6 and 7 further comprising a release device.

DESCRIPTION OF EMBODIMENTS

[107] Referring to Figure 1 there is shown conometric abutment 100 comprising dental prosthesis attachment member 102 and multi-unit abutment attachment member 104.

[108] Dental prosthesis attachment member 102 has a smooth conical frustum external face which narrows from the widest point to the narrowest point at a gradient of about 5°.

[109] Dental prosthesis attachment member 102 has a surface area operable to engage and form a friction fit attachment with a dental prosthesis of 80 mm².

[110] Conometric abutment 100 has linear recess slot 108 extending from opposing sides of the top face of dental prosthesis attachment member 102. Recess 108 is operable to engage with a flat head screw driver so that the screw driver when engaged can actuate rotation of the conometric abutment 100.

[111] Multi-unit abutment attachment member 104 has male attachment portion 104a that contains on the external face thereof helical thread 106 that extends from the bottom edge of dental prosthesis attachment member 102 to the bottom edge of attachment member 104.

[112] Dental prosthesis attachment member 102 and multi-unit abutment attachment member 104 are aligned with the longitudinal axis of the conometric abutment 100, such that they are substantially opposed. Conometric abutment 100 is substantially linear.

[113] Conometric abutment 100 is formed of titanium. Dental prosthesis attachment member 102 and multi-unit abutment attachment member 104 are integrally formed.

[114] Referring to Figure 2 there is shown a multi-unit abutment 400 formed of dental implant attachment member 402 and conometric abutment attachment member 404.

[115] Conometric abutment attachment member 404 has female attachment portion 404a. The internal face of female attachment portion 404a has helical thread 406 extending from the top edge of attachment member 404.

[116] Conometric abutment attachment member 404 is off-set from the longitudinal axis of the multi-unit abutment. Conometric abutment attachment member 404 is off-set by 17° relative to the longitudinal axis of the multi-unit abutment 400.

[117] Multi-unit abutment 400 comprises a bore 410 extending along the longitudinal axis of the multi-unit abutment 400. Bore 410 allows for the passage screw 412 into dental implant attachment member 402.

[118] Multi-unit abutment 400 comprises aperture 414 on the bottom face of dental implant attachment member 402, connected to bore 410, operable to receive screw 412.

[119] Referring to Figure 3 there is shown dental abutment 700 comprising conometric abutment 100 attached to multi-unit abutment 400. Dental abutment 700 is shown attached to dental implant 1100.

[120] Male attachment portion 104a of conometric abutment 100 is reversibly attached to female attachment portion 404a of multi-unit abutment 400, such that male attachment portion 104a is arranged within female attachment portion 404a.

[121 ] Helical thread 106 on male attachment portion 104a is complimentary to helical thread 406 on female attachment portion 404a, such that conometric abutment 100 is connected to multi-unit abutment 400 via rotation of conometric abutment 100 into multi-unit abutment 400 with, for example, an appropriate mating tool in recess 108, such as a screw driver. [122] To conometric abutment 100 from multi-unit abutment 400, a user rotates conometric abutment 100 with, for example, an appropriate tool in recess 108, such as a screw driver, until helical thread 106 is lifted from complimentary helical thread 406.

[123] Dental abutment 700 is reversibly attached to dental implant 1100 via screw 412 extending from aperture 414 the bottom of dental implant attachment member 402 of multi-unit abutment 400 into the top of dental implant 1100. In use, dental implant 1100 is fixed in the jaw bone of the user and dental abutment 700 extends upwardly from dental implant 1100.

[124] Conometric abutment 100 is off-set from the longitudinal axis of multi-unit abutment 400 and dental implant 1100. Conometric abutment is off-set by 17° relative to the longitudinal axis of multi-unit abutment 400 and dental implant 1100.

[125] Referring to Figure 4 there is shown conometric abutment 200 comprising dental prosthesis attachment member 202 and multi-unit abutment attachment member 204.

[126] Dental prosthesis attachment member 202 has a smooth conical frustum external face which narrows from the widest point to the narrowest point at a gradient of about 4°.

[127] Dental prosthesis attachment member 202 has a surface area operable to engage and form a friction fit attachment with a dental prosthesis of 80 mm².

[128] Conometric abutment 200 has linear recess slot 208 extending from opposing sides of the top face of dental prosthesis attachment member. Recess 208 is operable to engage with a flat head screw driver so that the screw driver when engaged can actuate rotation of t conometric abutment 200. Multi-unit abutment attachment member 204 has female attachment portion 204a and male attachment portion 204b. Male attachment portion 204b is arranged within female attachment portion 204a.

[129] Female attachment portion 204a is substantially free of a thread.

[130] Male attachment portion 204b contains on the external face thereof helical thread 206 that extends from the bottom edge of dental prosthesis attachment member 202 to the bottom edge of attachment member 204.

[131] Dental prosthesis attachment member 202 and multi-unit abutment attachment member 204 are aligned with the longitudinal axis of conometric abutment 200, such that they are substantially opposed. Conometric abutment 200 is substantially linear.

[132] Conometric abutment 200 is formed of titanium. Dental prosthesis attachment member 202 and multi-unit abutment attachment member 204 are integrally formed.

[133] Referring to Figure 5 there is shown multi-unit abutment 500 formed of dental implant attachment member 502 and conometric abutment attachment member 504. [134] Conometric abutment attachment member 504 has male attachment portion 504a and female attachment portion 504b. Female attachment portion 504b is arranged within male attachment portion 504a

[135] Male attachment portion 504a is substantially free of a thread.

[136] The internal face of female attachment portion 504b has helical thread 506 extending from the top edge of attachment member 504.

[137] Conometric abutment attachment member 504 is off-set from the longitudinal axis of the multi-unit abutment 500. Conometric abutment attachment member 504 is off-set by 17° relative to the longitudinal axis of multi-unit abutment 500.

[138] Multi-unit abutment 500 comprises bore 510 extending along the longitudinal axis of multiunit abutment 500. Bore 510 allows for the passage of screw 512 into dental implant attachment member 502.

[139] Multi-unit abutment 500 comprises aperture 514 on the bottom face of dental implant attachment member 502, connected to bore 510, operable to receive screw 512.

[140] Referring to Figure 6 there is shown dental abutment 800 comprising conometric abutment 200 attached to multi-unit abutment 500. Dental abutment 800 is shown attached to dental implant 1200.

[141 ] Male attachment portion 204b of conometric abutment 200 is reversibly attached to female attachment portion 504b of multi-unit abutment 500, such that male attachment portion 204b is arranged within female attachment portion 504b.

[142] Helical thread 206 on male attachment portion 204b is complimentary to helical thread 506 on female attachment portion 504b, such that conometric abutment 200 is connected to multi-unit abutment 500 via rotation of conometric abutment 200 into multi-unit abutment 500 with, for example, an appropriate tool in recess 208, such as a screw driver.

[143] Female attachment portion 204a of conometric abutment 200 is reversibly attached to male attachment portion 504a of multi-unit abutment 500, such that female attachment portion 204a is arranged within male attachment portion 504a.

[144] The surface of female attachment portion 204a is complimentary to male attachment portion 504a, such that when in contact, female attachment portion 204a and male attachment portion 504a are substantially flush.

[145] To detach conometric abutment 200 from multi-unit abutment 500, a user rotates conometric abutment 200 with, for example, an appropriate tool in recess 208, such as a screw driver until helical thread 206 is lifted from complimentary helical thread 506.

[146] Dental abutment 800 is reversibly attached to dental implant 1200 via screw 512 extending from aperture 514 the bottom of dental implant attachment member 502 of multi-unit abutment 400 into the top of dental implant 1200. In use, dental implant 1200 is fixed in the jaw bone of the user and dental abutment 800 extends upwardly from dental implant 1200.

[147] Conometric abutment 200 is off-set from the longitudinal axis of multi-unit abutment 500 and dental implant 1200. The conometric abutment attachment member off-set by 17° relative to the longitudinal axis of the multi-unit abutment 500and dental implant 1200.

[148] Referring to Figure 7 there is shown dental abutment 800 comprising conometric abutment 200 and multi-unit abutment 500 attached to dental implant 1200, as described above.

[149] Referring to Figure 8 there is shown dental abutment 800 comprising conometric abutment 200 and multi-unit abutment 500 attached to dental implant 1200, as described above, wherein conometric abutment 200 is attached to release device 1000.

[150] Release device 1000 is arranged in a friction fit over dental prosthesis attachment member 202 of conometric abutment 200.

[151 ] Release device 1000 is formed of housing 1012 and release member 1014.

[152] Housing 1012 is formed of titanium and has a generally cylindrical outer face with the exception of a central bore extending inwardly from the base of housing 1012 and exiting housing 1012 at a side face. The initial abutment-receiving portion of the central bore of housing 1012 is the same as dental prosthesis attachment member 202.

[153] At the top of the bore of housing 1012 is laterally extending captive release member 1014. Release member 1014 is generally of cylindrical shape except for cut-away portion 1014c, which is sized to receive the top portion of dental prosthesis attachment member 202. A first end 1014a of release member 1014 is arranged in an indent in the internal face of housing 1012. Release member 1014 then extends laterally through the bore of housing 1012 such that second end 1014b protrudes from the side wall of housing 1012. The upper face of end 1014b contains a hex screw drive.

[154] On the outer face of housing 1012 can be arranged a plurality of spaced perpendicularly extending retention lugs (not shown). A dental prosthesis (not shown) can be formed around the outer face of housing 1012, the retention lugs assist with securing release device 1000 within the prosthesis. In the present embodiment, release device 1000 would be arranged within the prosthesis such that screw drive-containing end 1014b of release member 1014 is accessible from a side face of the prosthesis.

To detach release device 1000 (and therefore the prosthesis) from conometric abutment 200, a user actuates the releasing force by causing rotation of release member 1014 with, for example, an appropriate tool, such as a screw driver. The user rotates release member 1014 until sufficient force is generated by the rotational action of release member 1014 abutting dental prosthesis attachment member 202 such that device 1000 is lifted from the friction fit with conometric abutment 200. With the friction fit released, the user may manually extract device 1000 from dental prosthesis attachment member 202 and proceed to clean release device 1000 and conometric abutment 200. To replace release device 1000 the user returns release member 1014 to the first position and places release device 1000 back over and conometric abutment 200.

Claims

1. A conometric abutment for use with a multi-unit abutment and a friction-fit dental prosthesis, wherein the conometric abutment comprises:

I. a dental prosthesis attachment member operable to engage with a dental prosthesis to form a friction fit attachment to the prosthesis; and ii. a multi-unit abutment attachment member operable to form an attachment to a multi-unit abutment.

2. A conometric abutment according to claim 1 , wherein the conometric abutment is substantially linear.

3. A conometric abutment according to claim 1 or 2, wherein the conometric abutment is formed by turning.

4. A kit of parts comprising: a. a conometric abutment according to any of claims 1 to 3; and b. a multi-unit abutment comprising:

I. a dental implant attachment member operable to engage with a dental implant to form an attachment to the dental implant; and ii. a conometric abutment attachment member operable to form an attachment to the conometric abutment, wherein the multi-unit abutment attachment member of the conometric abutment and the conometric abutment attachment member of the multi-unit abutment are operable to form an attachment.

5. A kit of parts according to claim 4, wherein the multi-unit abutment is operable to be reversibly attached to a dental implant.

6. A kit of parts according to claim 4 or 5, wherein the multi-unit abutment is operable to attach to a dental implant with rotation of a fixing member.

7. A kit of parts according to any of claims 4 to 6, wherein the multi-unit abutment is a computer-assisted design/computer-assisted manufacturing (CAD/CAM) multi-unit abutment.

8. A conometric abutment or kit of parts according to any preceding claim, wherein the multi-unit abutment attachment member of the conometric abutment is operable to form a reversible attachment with the multi-unit abutment.

9. A conometric abutment or kit of parts according to any preceding claim, wherein the attachment of the conometric abutment with the multi-unit abutment comprise a rotation attachment with cooperating threads.

10. A conometric abutment or kit of parts according to any preceding claim, wherein the multi-unit abutment attachment member of the conometric abutment comprises a male attachment portion comprising a thread.

11. A conometric abutment or kit of parts according to any preceding claim, wherein the multi-unit abutment attachment member of the conometric abutment comprises an integrally formed male attachment portion comprising a thread.

12. A conometric abutment or kit of parts according to any preceding claim, wherein the dental prosthesis attachment member of the conometric abutment comprises a tool engagement member operable to cooperate with a mating tool so as to provide leverage for the tool to actuate rotation of the conometric abutment.

13. A conometric abutment or kit of parts according to any preceding claim, wherein the conometric abutment attachment member of the multi-unit abutment comprises a female attachment portion comprising a thread.

14. A kit of parts according to any of claims 4 to 13, wherein the kit of parts further comprises: c. a dental prosthesis operable to form a friction fit attachment with the conometric abutment of any of claims 1 to 13, and/or dental cap operable to form an attachment with the conometric abutment of any of claims 1 to 13; and d. optionally, a dental implant.

15. A kit of parts according to claim 14, wherein the dental prosthesis comprises: a release device comprising a release member that is movable relative to the prosthesis from a first position to a second position; and wherein when the release member is in the first position the release device is not operable to impart a separating force to a friction fit attachment between the conometric abutment and the prosthesis and when the release member is in the second position the release device is operable to impart a separating force to a friction fit attachment between the conometric abutment and the prosthesis.