WO2025088134A1

WO2025088134A1 - A dental abutment for anchoring a dental appliance

Info

Publication number: WO2025088134A1
Application number: PCT/EP2024/080250
Authority: WO
Inventors: Henrik Andersen; Danilo Mogadouro CALCIOLARI; Nichlas Holst BUCH-LARSEN; Kostantinos ZARRAS; Kasper DUUS; Søren RANGSTRUP
Original assignee: Elos Medtech Pinol AS
Current assignee: Elos Medtech Pinol AS
Priority date: 2023-10-25
Filing date: 2024-10-25
Publication date: 2025-05-01
Anticipated expiration: 2026-04-25

Abstract

The present invention relates to a dental abutment and assembly for anchoring a dental appliance comprising means addressing, by allowing lateral and angular movements, deviation from tolerance generated at an interface between the dental abutment and a dental appliance produced by additive or subtractive manufacturing.

Description

A DENTAL ABUTMENT FOR ANCHORING A DENTAL APPLIANCE

FIELD OF THE INVENTION

The present invention relates to the field of oral implantation and to a dental abutment, an assembly and a prosthetic system for anchoring a dental appliance to a mouth of a patient.

BACKGROUND OF THE INVENTION

The field of dental prosthetics and restorative dentistry has seen significant advancements over the years. Dental implants have become a widely accepted solution for replacing missing teeth, and their success largely depends on the proper attachment of dental appliances such as crowns, bridges, or overdentures to the implant abutments.

Standard dentures have been a traditional solution for replacing missing teeth, providing individuals with a functional and aesthetically pleasing smile. These fully removable dentures are fitted into the mouth after all natural teeth have been extracted, and the mouth tissues have healed. While they serve as a viable option for tooth replacement, there are certain drawbacks associated with standard dentures that can impact a patient's quality of life.

There are several challenges with standard dentures.

When natural teeth are removed and replaced with standard dentures, the gum ridge, which previously supported the teeth, gradually begins to collapse over time. This loss of bone support can lead to a sunken appearance in the mouth, affecting facial aesthetics and potentially causing self-esteem issues.

Standard dentures rely on suction contact or denture adhesive to stay in place, which may not provide sufficient stability. As a result, dentures can become loose, leading to discomfort and potential irritation of the oral tissues. This instability can make eating and speaking challenging, impacting the overall quality of life for the denture wearer.

As dental technology and advancements in prosthetics continue to evolve, alternative solutions like implant-supported dental restorations and innovative dental abutments can offer improved outcomes, enhanced comfort, and a more natural experience for those seeking tooth replacement options. In particular, dental appliances produced by additive or subtractive manufacturing offer several advantages in terms of precision, customization, and efficiency. However, like any manufacturing method, they also come with certain challenges that need to be addressed to ensure optimal outcomes.

Both additive and subtractive manufacturing methods heavily rely on precise digital designs. Any inaccuracies in the design, calibration of the machines, or movement during manufacturing can affect the final product's fit and functionality.

High accuracy and precision throughout the manufacturing process cannot be always ensured leading to dental appliances that do not fit properly in the patient's mouth.

A dental abutment for anchoring a dental appliance produced by additive or subtractive manufacturing which can compensate for imperfect accuracy in the dental appliance production would be therefore advantageous.

Hence, an improved dental abutment and an assembly with compensatory features able to accommodate for dimensional variations and deviations from dimensional and geometric tolerances would be advantageous.

OBJECT OF THE INVENTION

An object of the present invention is to provide a dental abutment and an assembly that ensures a precise fit and improved longevity of implant-supported dental restorations, ultimately leading to enhanced patient satisfaction and quality of life.

A further object of the present invention is also to provide a dental abutment and an assembly that accommodates dimensional variations and deviations from dimensional and geometric tolerances in combination with dental appliances produced by additive or subtractive manufacturing.

An even further object of the invention may also be seen as to provide an alternative to the prior art.

In particular, it may be seen as an object of the present invention to provide a dental abutment and an assembly that accommodates dimensional variations and deviations from dimensional and geometric tolerances in combination with dental appliances produced by additive or subtractive manufacturing through the presence of compensatory features, swivelling capability, and reliable retentive force.

SUMMARY OF THE INVENTION

The above described object and several other objects are intended to be obtained in a first aspect of the invention by a dental abutment for anchoring a dental appliance produced by additive or subtractive manufacturing, the dental appliance having two or more receiving portions, the dental abutment having a distal end and a proximal end, the dental abutment comprising means compensating, by allowing swivelling, dimensional variations of each of the two or more receiving portion up to 500 |_im, such as lower than 400 |_im, thereby compensating deviations from dimensional and geometric tolerance at an interface between a dental appliance and the distal end of the dental abutment.

The dental abutment of the inventions is designed to secure a dental appliance created using additive or subtractive manufacturing methods. The dental appliance has multiple receiving portions, while the dental abutment itself comprises a distal end and a proximal end.

The dental abutment incorporates one or more elements allowing swivelling so as to provide compensation for dimensional variations in each of the two or more receiving portions, e.g. up to 300 pm, i.e. a swivelling up to 150 pm radius from the longitudinal axis of the dental abutment. This compensation effectively addresses deviations from dimensional and geometric tolerance that may occur at the interface between the dental appliance and the distal end of the dental abutment.

The geometric or engineering tolerance is defined as the allowable variation in dimension and geometry from a set value.

The invention solves issues generated, by the deviation from allowable variations, i.e. deviation from tolerance, at an interface between a dental appliance and the distal end of the dental abutment.

The dental appliance is a prosthetic device used in dentistry to replace missing teeth or support dental restorations like crowns, bridges, or dentures. Dental appliances can be manufactured using different techniques, including additive (3D printing) or subtractive (milling) manufacturing methods. These methods can introduce slight dimensional variations due to the complexity of the manufacturing process.

The dental appliances produced by additive or subtractive manufacturing have shown geometric tolerance issues produced at an interface between the dental appliance and the distal end of the dental abutment.

Dental appliances have generally two or more receiving portions. These receiving portions are the areas where the dental appliance will be attached or connected to the dental abutment.

Due to the manufacturing process or other factors, the receiving portions of the dental appliance might have dimensional variations of, e.g. up to 300 pm (micrometres). Such variations can result in discrepancies between the dental appliance and the dental abutment, affecting the overall fit and function of the dental prosthesis.

The dental abutment is designed to anchor or secure such dental appliances.

The dental abutment is equipped with means that allow swivelling or movement in response to the dimensional variations in the receiving portions of the dental appliance. This swivelling ability acts as compensation for the discrepancies in dimensional and geometric tolerances between the dental appliance and the dental abutment.

By compensating for these deviations, the dental abutment ensures a more precise and accurate fit of the dental appliance to the distal end of the dental abutment. This precise fit is crucial for a successful dental restoration, as it helps to maintain proper occlusion, i.e. bite, aesthetics, and overall comfort for the patient.

The dental abutment is a specially designed component with a compensation mechanism that addresses dimensional variations in the receiving portions of dental appliances. By allowing swivelling and accommodating these variations, the dental abutment ensures a more accurate and precise fit of the dental appliance, leading to a better-functioning dental appliance for the patient. In some embodiments, the compensating means are configured to provide a retentive force between 1 and 45 Newtons, such as between 5 and 25 Newtons.

These means are indeed designed to achieve a retentive force between 5 and 25 Newtons, with an ideal range between 10 and 20 Newtons.

The retentive force refers to the force or resistance with which the dental appliance is held securely in place by the dental abutment. It is crucial for the dental appliance to have an adequate level of retention to ensure stability and proper function.

The dental abutment is designed to provide a retentive force within a specific range. In this case, the range is between 5 and 25 Newtons. Newtons is the unit used to measure force, and in this context, it refers to the amount of force applied to retain the dental appliance in place.

In some further embodiments, the compensating means are configured to allow for swivelling in a range between 0 and 30 degrees, such as 15 degrees.

The inclusion of the swivelling feature in the dental abutment, allowing movement in a range between 0 and 30 degrees, with an ideal range of 15 degrees, serves several important purposes in the context of the dental appliance and the patient's oral health.

The swivelling ability of the dental abutment allows it to adjust to minor misalignments or angular variations that may be present in the receiving portions of the dental appliance. During the fabrication or fitting process, it is common for small deviations to occur, and the swivelling feature helps to accommodate these variations.

By allowing movement within a certain range, the dental abutment can achieve a more customized and precise fit with the dental appliance. This can enhance the overall comfort for the patient by reducing any potential pressure points or discomfort caused by an overly rigid fit.

The swivelling feature helps in distributing the forces and stresses exerted on the dental appliance more evenly. It can prevent excessive stress from being concentrated on a specific area, which could lead to premature wear or damage to the dental prosthesis. The swivelling feature of the dental abutment, with a range between 0 and 30 degrees and an ideal range of 15 degrees, provides flexibility, adaptability, and improved fit for the dental appliance. It allows the abutment to compensate for minor misalignments, distribute forces effectively, and accommodate the dynamic environment of the oral cavity, ultimately leading to a more comfortable and functional dental restoration for the patient.

In some embodiments, the means comprises one or more protrusions on an inner surface and the distal end comprises one or more depressions defining a gap between the inner surface and the distal end of the dental abutment.

The one or more depressions may be an annular cut out on the distal end of the dental abutment.

The presence of the gap or a space addresses variations in both size and shape at the junction between a dental appliance and the dental abutment.

The presence of recesses or depressions creates the gap between the distal end of the dental abutment and the compensating means.

As a result, the dental abutment can move in relation to the means.

The one or more protrusions of the means for compensating and the one or more depressions or annular cut out on the distal end of the dental abutment have dimensions allowing the dental abutment to swivel within a range of 0 to 30 degrees, effectively compensating for size variations in the receiving portions of the dental appliance that it accommodates.

In some further embodiments, the dental abutment is a metal dental abutment.

In some even further embodiments, the compensating means are fastened to the dental abutment via fastening means.

Fastening may be referred to as secured to, such as locked in position.

In some embodiments, the fastening may be by laser welding, gluing, threading, press fit, snap fit or by interference fit.

The gap and thus the one or more depressions or annular cut out may be formed within the distal end of the dental abutment or within the fastening means or within a further element located onto or around the distal end of the dental abutment and fasten to the distal end. In some embodiments, the compensating means are or comprise a ring structure.

The ring structure may be an annular, square, or conical ring, such as an open, such as at least partially open, circular ring-shaped structure.

The inclusion of a ring structure as part of the means of the dental abutment serves several functional purposes, offering versatility and adaptability in various dental restoration scenarios.

The ring structure, whether it is annular, square, or conical, with an open or partially open circular ring-shaped design, can flexibly accommodate dimensional variations in the receiving portions of the dental appliance. Its open or partially open nature allows it to adapt and adjust to slight differences in size and shape of the dental appliance, ensuring a more precise fit.

The ring structure's open design provides the necessary space for swivelling or movement of the dental appliance within the abutment. As mentioned earlier, this movement allows the dental appliance to compensate for any angular or positional deviations, providing a better fit and comfort for the patient.

Incorporating a ring structure as part of the means of the dental abutment adds flexibility, load distribution, and customization options to accommodate different dental appliances and patient needs. Its open or partially open design allows for movement, compensates for dimensional variations, and contributes to improved comfort and functionality of the dental restoration.

A dental abutment with an appropriate level of rigidity ensures that the dental appliance remains securely anchored and properly aligned, maintaining a stable and functional restoration. It also helps to distribute forces evenly and reduce stress concentrations, which can contribute to the longevity and success of the dental prosthesis.

The abutment of the invention achieves a balance between sufficient rigidity for stability and support and enough flexibility to accommodate minor adjustments and variations. In some embodiments, the compensating means are configured to engage, such as to snap engage, with a receiving portion of a dental appliance, such as a dental appliance produced by additive or subtractive manufacturing.

The snap engagement allows them to securely connect or "snap engage" with a receiving portion of a dental appliance.

The dental abutment is equipped with specific features or elements that facilitate a secure and firm connection with the receiving portion of a dental appliance. This connection is achieved through a snapping action, which ensures a reliable and stable attachment between the abutment and the dental appliance.

The term "snap engage" implies a quick and effortless locking or fitting process. When the dental appliance is brought into contact with the dental abutment, the mechanisms within the abutment enable it to "snap" or securely fit into the receiving portion of the appliance. This snapping engagement creates a strong bond between the two components, ensuring that the dental appliance remains firmly anchored to the abutment.

By using a snap engagement mechanism, the dental abutment offers ease of use for dental professionals during the restoration process. It allows for efficient and reliable assembly of the dental appliance, contributing to the overall success and longevity of the dental restoration for the patient.

These features are designed to address the unique challenges and requirements that arise when attaching a dental appliance with multiple receiving portions to the dental abutment.

When a dental appliance has multiple receiving portions, there is a higher likelihood of slight dimensional variations between these portions. These variations can arise due to the complexity of the manufacturing process or other factors. The compensation mechanism in the dental abutment allows it to adjust and accommodate these variations in each of the receiving portions, ensuring a precise fit and proper alignment of the dental appliance.

Dental appliances with multiple receiving portions may have more complex geometries, and they need to fit accurately onto the dental abutment. The swivelling capability of the abutment allows the dental appliance to pivot or move within a certain range, making it easier to align the multiple receiving portions with the abutment's corresponding structures. This flexibility helps in achieving an optimal fit for the entire dental appliance.

The dental abutment features discussed are especially pertinent when the dental appliance has two or more receiving portions due to the increased complexity and potential for dimensional variations in such cases.

In a second aspect, the invention relates to a dental assembly for anchoring a dental appliance in oral implantation, the dental assembly comprising : a dental abutment according to the first aspect of the invention; a cap for securing in a receiving portion of a dental appliance, such as a dental appliance produced by additive or subtractive manufacturing.

In some embodiments, additional components are required to provide further stability and retention for the dental prosthesis.

The assembly includes a cap designed to be secured within the dental appliance's receiving portion.

The assembly is designed to work together to secure the dental appliance firmly in place.

In some embodiments of the second aspect of the invention, the cap is configured to engage with the compensating means and comprises an external self-cutting thread for securing to a receiving portion of a dental appliance.

The external self-cutting thread facilitates its secure attachment to the receiving portion of the dental appliance.

This engagement ensures a strong and secure fit between the two components. This thread allows the cap to be easily and precisely screwed onto the receiving portion of the dental appliance. As the cap is screwed in, the self-cutting thread creates its own path, ensuring a tight and accurate fit.

In some further embodiments, the cap defines, i.e. delimits, a cavity comprising means for allowing swivelling of the dental abutment once engaged.

The means for allowing swivelling of the dental abutment once engaged may comprise a pivot point on an internal surface of the cap, such as a conical shaped surface. The inclusion of a pivot point on an internal surface of the cap, such as a conicalshaped surface, serves a specific functional purpose in the assembly of the dental abutment and cap with the dental appliance. The pivot point allows for controlled movement and alignment adjustments during the process of securing the cap to the dental appliance's receiving portion.

As discussed earlier, the dental abutment is equipped with mechanisms that allow swivelling or movement to compensate for dimensional variations in the dental appliance's receiving portions. Similarly, the cap is designed to work in conjunction with the dental abutment and dental appliance to achieve a precise fit and alignment.

The cap is constructed with an internal surface, such as a conical-shaped surface, serving as a pivot point. The conical shape provides a smooth and gradual slope, allowing controlled movement when the cap engages with the receiving portion of the dental appliance.

When the cap is screwed onto the dental appliance's receiving portion, the conical-shaped pivot point allows slight angular adjustments. This means that the cap can pivot or swivel slightly during the tightening process, ensuring that it aligns precisely with the abutment and dental appliance.

Dental restorations require a high level of precision and accuracy for a successful outcome. However, there may be minor variations in the manufacturing of the dental appliance or the dimensions of the receiving portion. The pivot point in the cap allows for these small tolerances, accommodating them and ensuring a proper fit.

By incorporating the pivot point, the cap can achieve an optimal fit and stability when secured to the dental appliance's receiving portion. The controlled swivelling action during tightening helps align the cap and abutment with the dental appliance precisely, contributing to the overall success and longevity of the dental restoration.

The cap's internal conical-shaped surface as a pivot point enhances the assembly's functionality by allowing controlled swivelling and alignment adjustments. This ensures a precise fit between the cap, abutment, and dental appliance, compensating for any minor variations in manufacturing or dimensions. The pivot point's inclusion contributes to the stability and effectiveness of the dental restoration, providing patients with a well-fitted and functional dental prosthesis.

The dental assembly may further comprise a compressible element, such as a compressible annular ring, configured to be located within the cap.

The cap may be a metal cap.

In some further embodiments, the dental assembly further comprises a dental implant having an internal threaded portion configured to engage with a threaded portion of the proximal end of the dental abutment.

This compressible element provides additional stability, retention, and adaptability, enhancing the overall performance and longevity of the dental restoration.

Dental appliances and their receiving portions may have further slight dimensional variations or irregularities. The compressible element, being annular and compressible, can adapt to these variations, ensuring a more accurate and secure fit between the cap and the dental appliance's receiving portion.

Like the swivelling capability and the pivot point, the compressible element helps compensate for small dimensional deviations that may occur during the manufacturing process. Its compressible nature allows it to adjust and fill any gaps, providing a more stable connection.

The compressible nature of the annular ring can provide a cushioning effect between the cap and the dental appliance.

In a further aspect, the invention relates to a dental prosthetic system comprising: a dental assembly according to the second aspect of the invention; a dental appliance produced by additive or subtractive manufacturing, the dental appliance having two or more receiving portions.

The invention relates also to the following items:

1. A dental abutment, comprising : a base member having a proximal end portion, and a distal end portion; an attachment member including a main body and a proximal extension member; wherein a gap is defined between an inner surface of the distal end portion of the base member and an outer surface of the attachment member; such that an axis extending proximally and distally through the dental abutment can be disposed at an angle between 0 and 30 degrees relative to an axis extending proximally and distally through the dental appliance.

2. The dental abutment of item 1 configured to provide a retentive force between 10 and 20 Newtons to the dental appliance.

Base member and attachment member may be the only elements providing the function of allowing for compensation of, by allowing swivelling, dimensional variations of each of said two or more receiving portion up to 500 |_im, such as lower than 400 |_im, thereby compensating deviations from dimensional and geometric tolerance at an interface between a dental appliance and the dental abutment.

In some embodiments, the gap may be present on a coupling member that is surrounding the base member and fasten to it by means of welding, such as laser welding, press fit or gluing.

The invention relates also to the following items:

3. A dental abutment, comprising: a base member having a proximal end portion including a threaded portion, and a distal end portion comprising a first inner bore; an attachment member including a main body and a proximal extension member disposed within the first inner bore, the main body comprising an annular cutout; and a coupling member comprising a second inner bore and including an annular projection extending into the second inner bore, the annular projection configured to be disposed within the annular cutout, wherein a gap is defined between an inner surface of the coupling member including an inner surface of the annular projection and an outer surface of the attachment member; wherein the coupling member is configured to couple a dental appliance such that an axis extending proximally and distally through the dental abutment can be disposed at an angle between 0 and 30 degrees relative to an axis extending proximally and distally through the dental appliance.

4. The dental abutment of item 3, wherein the coupling member has a C- shape in cross section and includes a plurality of openings extending through a side wall.

5. The dental abutment of item 3, wherein the coupling member is configured to provide a retentive force between 10 and 20 Newtons to the dental appliance.

6. The dental abutment of item 3, further comprising a cap member defining an internal cavity and including a frustoconical protrusion extending into the internal cavity, wherein the cap member is configured to couple the coupling member via a snap-fit connection.

7. The dental abutment of item 6, wherein a distal surface of the attachment member abuts an apex of the frustoconical protrusion such that the cap member can pivot relative to the base member about a pivot point defined by the apex.

8. The dental abutment of item 7, wherein the cap member is configured to pivot between 0 and 30 degrees relative to an axis extending proximally and distally through the base member.

9. The dental abutment of item 6, wherein an outer surface of the cap member comprises a self-cutting screw portion.

10. The dental abutment of item 6, further comprising a compressible member disposed between the cap member and the coupling member.

11. The dental abutment of item 10, wherein the compressible member is an annular ring.

12. The dental abutment of item 3, wherein the dental abutment is configured to form a snap fit with the dental appliance. 13. A dental abutment, comprising: a base including a proximal end portion configured to be implanted in a subject, and a distal end portion; attachment means configured to couple the distal end portion of the base; a cap disposed over the distal end portion of the base and the attachment means, the cap defining an internal cavity and comprising a pivot member extending into the internal cavity; and coupling means disposed between the attachment means and the cap; wherein a gap is defined between an inner surface of the coupling means and an outer surface of the attachment means such that the coupling means is movable relative to the attachment means; wherein the coupling means is configured to provide a retentive force between 10 and 20 Newtons to a dental appliance coupled to the cap; and wherein the cap is configured to pivot between 0 and 30 degrees relative to an axis extending proximally and distally through the base.

14. The dental abutment of item 13, further comprising a compressible member disposed between the cap and the coupling means.

15. The dental abutment of item 13, wherein a distal end portion of the base comprises a threaded aperture and the attachment means comprises a projection having a correspondingly threaded external surface.

16. The dental abutment of item 13, wherein the coupling means defines an opening therethrough and a projection configured to couple a corresponding recess in a distal end portion of the attachment means.

17. The dental abutment of item 13, wherein an outer surface of the cap comprises a self-cutting threaded portion.

18. The dental abutment of item 13, wherein the pivot member comprises a frustoconical shape.

19. A dental assembly, comprising: a dental appliance; and a dental abutment coupled to the dental appliance, comprising: a base member having a proximal end portion including a threaded portion, and a distal end portion comprising a first inner bore, an attachment member including a main body and a proximal extension member disposed within the first inner bore, the main body comprising an annular cutout, and a coupling member comprising a second inner bore and including an annular projection extending into the second inner bore, the annular projection configured to be disposed within the annular cutout, the coupling member configured to be movable relative to the attachment member; wherein the coupling member provides a retentive force between 10 and 20 Newtons to the dental appliance.

20. The dental assembly of item 19, wherein the dental appliance has two or more receiving portions.

21. The dental assembly of item 19, wherein the dental abutment pivots between 0 and 30 degrees relative to an axis extending proximally and distally through the dental appliance.

22. The dental assembly of item 19, wherein the dental assembly compensates for tolerances between the dental appliance and dental abutment of up to 500 pm.

The first, second and other aspects, embodiments and items of the present invention may each be combined with any of the other aspects, embodiments and items. These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter. BRIEF DESCRIPTION OF THE FIGURES

The dental abutment, assembly and prosthetic system according to the invention will now be described in more details with regard to the accompanying figures. The figures show one way of implementing the present invention and are not to be construed as being limiting to other possible embodiments falling within the scope of the attached claim set.

Figures 1A and IB show a schematic view of the dental abutment according to some embodiments of the invention.

Figures 1C-1F show a schematic front views and cross sections of the dental assembly according to some embodiments of the invention.

Figures 2A and 2B show a 3 D view of the dental abutment according to some embodiments of the invention.

Figure 3 shows a cross section of the dental assembly comprising a cap according to some embodiments of the invention.

Figure 4 shows a cross section of the dental assembly comprising a compressible element according to some embodiments of the invention.

Figure 5 show a 3 D view of the dental assembly comprising a dental implant according to some embodiments of the invention.

Figure 6 shows a cross section of the dental assembly comprising an element surrounding the dental abutment according to some embodiments of the invention.

Figure 7 shows a cross section of the dental assembly comprising means compensating dimensional variations of the receiving portions of the dental appliance within the distal end of the dental abutment.

Figures 8A-8D show a front view and cross sections of the dental assembly according to some embodiments of the invention.

DETAILED DESCRIPTION OF AN EMBODIMENT

Figures 1A and IB show a schematic view of the dental abutment 22 and 30 for anchoring a dental appliance having two or more receiving portions, having a distal end 25 and 27 a proximal end 26 and 28. The proximal end or proximal end portion 26 and 28 of the dental abutment of figures 1A and IB are a base or base member configured to be engaged with an implant to be implanted in a subject. The dental abutments 22 and 30 comprise means 23 and 29 compensating, by allowing swivelling, dimensional variations of each of the two or more receiving portion of the dental appliance.

The means 23 and 29 are fasten to the dental abutment 22 and 30 via fastening means 24 compensating, by allowing swivelling, dimensional variations of each of the two or more receiving portion up to 500 |_im.

Figures 2A and 2B show a 3 D view of the dental abutment 2 and 4, for anchoring a dental appliance having two or more receiving portions, having a distal end 5 and 7 and a proximal end 6 and 8.

The proximal end or proximal end portion 6 and 8 of the dental abutment of figures 2A and 2B are a base or base member including a threaded portion. The proximal end or proximal end portion 6 and 8 is configured to be engaged with an implant to be implanted in a subject.

The distal end or distal end portion 5 and 7 of the dental abutment comprises a first inner bore.

The dental abutment 2 comprises means 3 and 9 compensating, by allowing swivelling, dimensional variations of each of the two or more receiving portion of the dental appliance.

The means 3 and 9 of figures 2A and 2B comprise a ring structure, being an annular ring, such as at least partially open, circular ring-shaped structure. The ring structure may also be a square or conical.

The means 3 and 9 are configured to engage, such as to snap engage, with a receiving portion of a dental appliance.

The means 3 and 9 of figures 2A and 2B may be seen as a coupling member comprising a second inner bore and including an annular projection extending into the second inner bore, the annular projection configured to be disposed within an annular cutout on the fastening means or attachment member.

In other embodiments, the annular cutout may be on the distal end of the dental abutment or on a further element located onto or surrounding the distal end of the dental abutment.

The means 3 and 9 of figures 2A and 2B allow for compensating, by allowing swivelling, dimensional variations of each of the two or more receiving portion up to 500 nm, such as lower than 400 |_im, thereby compensating deviations from dimensional and geometric tolerance at an interface between the dental appliance and said distal end or distal end portion 5 of the dental abutment.

The coupling member is configured to couple a dental appliance such that an axis extending proximally and distally through the dental abutment can be disposed at an angle between 0 and 30 degrees relative to an axis extending proximally and distally through the dental appliance.

The coupling members or means 3 and 9 are fasten to the dental abutment 2 and 4 via fastening means 1.

The fastening means 1 of figure 2A may be seen as attachment member including a main body and a proximal extension member disposed within the first inner bore of the dental abutment or base member.

The fastening means or attachment member 1 of figures 2A and 2B is characterized by a main body comprising an annular cutout.

The presence of the annular cut out creates a gap defined between an inner surface of the coupling member including an inner surface of the annular projection and an outer surface of the attachment member.

This gap allows for swivelling of the coupling member compensating dimensional variations of each of the two or more receiving portion up to 500 |_im.

The gap is defined between an inner surface of the coupling member or means 3 and 9 and an outer surface of the attachment member or fastening means 1 such that the coupling means is movable relative to the attachment member.

Figure 3 shows a cross section of the dental assembly 15 comprising a cap 14 according to some embodiments of the invention.

The dental assembly 15 for anchoring a dental appliance in oral implantation comprises a dental abutment and a cap 14 for securing in a receiving portion of a dental appliance.

The cap 14 is configured to engage with the ring structure 17 and comprises an external self-cutting thread 19 for securing to a receiving portion of a dental appliance.

The cap 14 defines a cavity comprising means 20 for allowing swivelling of the dental abutment once engaged.

The means 20 comprises a pivot point on an internal surface of the cap 14, such as a conical shaped surface. The cap disposed over the distal end portion of the base and the coupling member or means, i.e. the ring structure 17, defines an internal cavity and comprises a pivot member extending into the internal cavity.

The coupling means 17, fasten through attachment member 42, is configured to provide a retentive force between 10 and 20 Newtons to a dental appliance coupled to the cap.

The cap is configured to pivot between 0 and 30 degrees relative to an axis extending proximally and distally through the base.

A gap 21 is defined between an inner surface of the fastening means 42 and an outer surface of the ring structure 17.

This gap allows for swivelling of the attachment member compensating dimensional variations of each of the two or more receiving portion up to 500 |_im.

Figure 4 shows a cross section of the dental assembly 16 comprising a compressible element 13 according to some embodiments of the invention.

The compressible element 13 is a compressible annular ring, configured to be located within the cap 18.

Figure 5 shows a 3 D view of the dental assembly 10 comprising a dental implant 11 according to some embodiments of the invention having an internal threaded portion configured to engage with a threaded portion 31 of the proximal end of the dental abutment 12.

Figure 6 shows a cross section of the dental assembly 32 comprising element 36 surrounding the dental abutment 34.

Element 36 is connected or fasten to a protrusion 37 of the dental abutment 34 by means of welding, press fit or gluing. Other fastening means may be used.

Element 36 is a mean compensating deviation from dimensional and geometric tolerance at an interface between a dental appliance and the dental abutment 34. Element 36 is characterized by the presence of one or more depressions or annular cut out on its external surface defining a gap between the surface of element 36 and the surface of the ring structure 43 such that element 36 and thus dental abutment 34 is movable relative to the ring structure 43.

The one or more depressions or annular cut out define a gap 35 between a surface of the element 36 and the surface of the ring structure 43, having a protrusion area 44 complementary to the depression defining the gap 35. Protrusion area 44 has a dimension allowing swivelling movement of element 36 and thus dental abutment 34 in a range between 0 and 30 degrees, compensating dimensional variations of the receiving portions of the dental appliance.

Figure 7 shows a cross section of the dental assembly 33 comprising means compensating dimensional variations of the receiving portions of the dental appliance within the distal end 41 of the dental abutment 40.

The distal end 41 of the dental abutment 40 comprises means compensating deviations from dimensional and geometric tolerance at an interface between a dental appliance and the dental abutment 40 being a gap 38 combined with protrusion 45 of the ring structure 39.

The distal end 41 of the dental abutment 40 is characterized by the presence of one or more depressions on its external surface defining a gap 38 between the surface of distal end 41 and the surface of the ring structure 39 such dental abutment 40 is movable relative to the ring structure 39.

The one or more depressions or annular cut out define a gap 38 between a surface of the distal end 41 of the dental abutment 40 and the surface of the ring structure 43, having a protrusion area 45 complementary to the depression defining the gap 38. Protrusion area 45 has a dimension allowing swivelling movement of the dental abutment 40 in a range between 0 and 30 degrees, compensating dimensional variations of the receiving portions of the dental appliance.

Figure 8A shows a front view of a dental assembly 46 comprising a dental abutment 51 and a cap 48. Figure 8B shows a cross section of the dental assembly 46 for anchoring a dental appliance in oral implantation, produced by additive or subtractive manufacturing and having two or more receiving portions.

The dental assembly 46 comprises a dental abutment 51 for anchoring a dental appliance, the dental assembly having a distal end 49 and a proximal end 50. The dental assembly 46 also comprise a cap 48, for securing the dental abutment in a receiving portion of a dental appliance. The cap 48 comprises means compensating dimensional variations of each of the two or more receiving portion up to 500 nm, such as lower than 400 |_im, by allowing, as shown in figure 8D, horizontal (AH) and vertical (AV) movement of ±0.15 mm and, as shown in figure 8D, rotational movement of (Acp) of ±8° in respect to the central longitudinal axis of the dental abutment. The means compensating dimensional variations of each of the two or more receiving portion are or comprise a ring structure 47, as shown in figure 8C, thereby compensating deviations from dimensional and geometric tolerance at an interface between a dental appliance and the distal end 49 of the dental abutment 51.

The idea of the solution shown in figures 8A-8D allows for horizontal (AH) and vertical (AV) movement of ±0.15 mm as well as rotational movement of (Acp) of ±8° in respect to the central longitudinal axis of the dental abutment.

The cap may be considered, and referred to, as the permanent part, while the ring structure, or retention ring, may be considered, and referred to, as the sacrificial part.

Once in place, in the dental prosthetic system both cap ad ring structure are located in the denture to allow for easy access and replacement of the sacrificial ring, while the abutment is place in the implant.

Retention is achieved by pushing the abutment, having for example, as shown in figure 8A-8D a spherical or semi-spherical upper geometry.

In other embodiments, the distal end may have other upper geometry than spherical. The distal end may be made of titanium.

The final dental prosthetic system is produced by forcing at least two abutments into a dental appliance or denture produced by additive or subtractive manufacturing dental appliance having two or more receiving portions. The abutments are pushes through an undersized ring as shown in figures 8A-8D. The ring may be made a deformable material, thus deforming as the abutment is pressed though.

In some embodiments, the ring is made of PEEK.

To allow for multiple retentions, the diameter of both the inner and outer surfaces of the ring can be adjusted, ensuring consistent engagement with the abutment and prolonging the system's usability.

Figures 8A-8D describe an embodiment in which the cap 48 has a self-cutting threaded portion to secure attachment to the receiving portion of the dental appliance or denture.

In some other embodiments the cap internal geometry may be produced within the receiving portions of the dental appliance or denture by additive or subtractive manufacturing. In these embodiments, the features of the internal structure of the cap are therefore reproduced within the receiving portions of the denture, thus removing the need of a cap.

In these embodiments, as shown in figures 1C-1D and in figures 1E-1F the dental assembly comprises as essential features the abutment 53 and the ring structure 54.

Figures 1C and IE show respectively a front view and a cross section of the dental assembly before the abutment 53 and the ring structure 54 are assembled.

Figures ID and IF show respectively a front view and a cross section of the dental assembly 55 after the abutment 53 with a spherical upper geometry, with a diameter larger than the opening of the ring structure 54, is pushed through the opening. The deformation of the ring structure 54 allow for the abutment 53 to be pressed through the opening and ensure engagement with the abutment.

The presence of gaps (not shown) in between the opening of the ring structure and the abutment allow for horizontal, vertical and rotational movements as shown in figures 8C and 8D.

Although the present invention has been described in connection with the specified embodiments, it should not be construed as being in any way limited to the presented examples. The scope of the present invention is set out by the accompanying claim set. In the context of the claims, the terms "comprising" or "comprises" do not exclude other possible elements or steps. Also, the mentioning of references such as "a" or "an" etc. should not be construed as excluding a plurality. The use of reference signs in the claims with respect to elements indicated in the figures shall also not be construed as limiting the scope of the invention. Furthermore, individual features mentioned in different claims, may possibly be advantageously combined, and the mentioning of these features in different claims does not exclude that a combination of features is possible and advantageous.

Claims

1. A dental assembly (15,46) for anchoring a dental appliance in oral implantation, said dental appliance produced by additive or subtractive manufacturing and having two or more receiving portions, said dental assembly comprising:

- a dental abutment (2,4,22,30,51) for anchoring said dental appliance, said dental abutment (2,4,22,30, 51) having a distal end (5,7,49) and a proximal end (6,8,50),

- means (3,9,17,47) compensating dimensional variations of each of said two or more receiving portion up to 500 |_im, such as lower than 400 |_im, by allowing horizontal (AH) and vertical (AV) movement of ±0.15 mm and rotational movement of (Acp) of ±8° in respect to the central longitudinal axis of said dental abutment and wherein said means (3,9,17,47) are or comprise a ring structure

(3.47), thereby compensating deviations from dimensional and geometric tolerance at an interface between a dental appliance and said distal end (5,7,49) of said dental abutment (2,4,22,30,51).

2. A dental assembly (15,46) according to claim 1, wherein said means

(3.9.17.47) are configured to provide a retentive force between 1 and 45 Newtons, such as between 5 and 25 Newtons.

3. A dental assembly (15,46) according to any of the preceding claims, wherein said means are configured to allow for swivelling in a range between 0 and 30 degrees, such as 15 degrees.

4. A dental assembly (15,46) according to any of the preceding claims, wherein said means (3,9,17,47) comprises one or more protrusions on an inner surface and said distal end comprises one or more depressions defining a gap between said inner surface and said distal end of said dental abutment.

5. A dental assembly (15,46) according to any of the preceding claims, wherein said ring structure (3) is an annular or square or conical ring, such as an open, such as at least partially open, circular ring-shaped structure.

6. A dental assembly (15,51) according to any of the preceding claims wherein said means (3,9,17,47) are configured to engage, such as to snap engage, with a receiving portion of a dental appliance, such as a dental appliance produced by additive or subtractive manufacturing.

7. A dental assembly (15,51) according to any of the preceding claims, further comprising:

- a cap (14,18,48) for securing in a receiving portion of a dental appliance, such as a dental appliance produced by additive or subtractive manufacturing.

8. A dental assembly (15,51) according to claim 7, wherein said cap (14,18,48) comprises said means (3,9,17,47).

9. A dental assembly (15,46) according to any of the preceding claims, wherein said cap (14,18,48) is configured to engage with said means (3,9,17,47) and comprises an external self-cutting thread (19) for securing to a receiving portion of a dental appliance.

10. A dental assembly (15,46) according to any of the preceding claims, wherein said cap (14,18,48) defines a cavity comprising means (20) for allowing swivelling of said dental abutment once engaged.

11. A dental assembly (15,46) according to any of the preceding claims, wherein said means (20) for allowing swivelling of said dental abutment once engaged comprise a pivot point on an internal surface of said cap (14,18,48), such as a conical shaped surface.

12. A dental assembly (15,16,46) according to any of the preceding claims, further comprising a compressible element (13), such as a compressible annular ring, configured to be located within said cap (14, 18,48).

13. A dental assembly (10,15,16,46) according to any of the preceding, further comprising a dental implant (11) having an internal threaded portion configured to engage with a threaded portion (31) of said proximal end of said dental abutment.

14. A dental prosthetic system comprising : - a dental assembly according to any of the preceding claims;

- a dental appliance produced by additive or subtractive manufacturing, said dental appliance having two or more receiving portions.