WO2025140996A1

WO2025140996A1 - Dental component with improved retention

Info

Publication number: WO2025140996A1
Application number: PCT/EP2024/088080
Authority: WO
Inventors: Sebastien Daniel BARRIERE; Ruben Gerrit Sasha ZIMMERMANN; Marc Tosetti; Wei-Neng HSU
Original assignee: Institut Straumann AG
Current assignee: Institut Straumann AG
Priority date: 2023-12-28
Filing date: 2024-12-20
Publication date: 2025-07-03
Anticipated expiration: 2026-06-28

Abstract

Provided herein is a dental component (100) comprising: an apical end (12'); a coronal end (10'); an attachment portion (104) extending from the apical end in a coronal direction along an attachment portion central longitudinal axis, the attachment portion being configured for connection to a dental implant component (200); and a prosthetic connection portion (102) extending from the coronal end in an apical direction along a prosthetic connection portion central longitudinal axis (A-A'), the prosthetic connection portion being configured for connection to a prosthetic component (300), the prosthetic connection portion comprising a lateral outer surface (106); wherein the lateral outer surface (106) comprises one or more roughened area (110) each provided with a regular pattern of microstructures (170), the regular pattern of microstructures covering the entire surface of the one or more roughened area (110).

Description

DENTAL COMPONENT WITH IMPROVED RETENTION

Field of the invention

The present invention is in a field of dental implantation systems, in particular in the field of copings or abutments.

Background to the invention

Dental implants are used to replace one or more teeth in the jawbone of a patient. The implant typically consists of two parts, an anchoring part and a support part, which can be formed integrally or as separate components. The anchoring part is inserted into the jawbone, where it osseointegrates with the bone. This component typically has an external screw thread for fastening to the bone. The support part protrudes above the jawbone and provides a support for the dental prosthesis, e.g. bridge or crown. The prosthesis can be connected to the support part via bonding (also called gluing, or cementing) or via a screw thread. When the anchoring and support parts are formed separately, the anchoring part in isolation is referred to as the implant while the support part is commonly known as an abutment.

One such abutment that can be used for cemented connection to the prosthesis is described in EP2601906.

When attaching the prosthesis via gluing it is important to obtain a good adhesion between the abutment surface and the cement, in order to obtain a firm retention of the prosthesis. When the surface of the abutment is smooth, this can result in inadequate cement adhesion. To overcome this issue, various roughening techniques are known. For example, some dentists may opt to sandblast the abutment prior to fixation of the prosthesis.

Sandblasting requires the use of small particles, for example alumina, which are directed at high speed against the surface of the product. This method does not allow for precise application of the roughened surface and hence any surfaces which should remain smooth, e.g. sealing surfaces for connection to the implant, must be protected during the sandblasting process. The abutment must then be cleaned afterwards in order to remove any particles that might remain on the surface. There is thus the possibility of damage to and contamination of the abutment if the sandblasting and subsequent cleaning is not carried out correctly. It is also known for abutment manufacturers to provide grooves or other geometries on the surface of the abutment in order to enhance cement retention (e.g. EP3023078 and EP3487442).

However, there remains a need to provide an abutment surface with an enhanced surface roughness for promoting cement adhesion which is fast, reliable, and cost effective to produce.

Summary of the invention

Before the present system and method of the invention are described, it is to be understood that this invention is not limited to particular systems and methods or combinations described, since such systems and methods and combinations may, of course, vary. It is also to be understood that the terminology used herein is not intended to be limiting, since the scope of the present invention will be limited only by the appended claims.

As used herein, the singular forms "a", "an", and "the" include both singular and plural referents unless the context clearly dictates otherwise.

The terms "comprising", "comprises" and "comprised of' 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. It will be appreciated that the terms "comprising", "comprises" and "comprised of' as used herein comprise the terms "consisting of", "consists" and "consists of'.

The recitation of numerical ranges by endpoints includes all numbers and fractions subsumed within the respective ranges, as well as the recited endpoints.

The term "about" or “approximately” as used herein when referring to a measurable value such as a parameter, an amount, a temporal duration, and the like, is meant to encompass variations of +/-10% or less, preferably +/-5% or less, more preferably +/-1 % or less, and still more preferably +/-0.1 % or less of and from the specified value, insofar such variations are appropriate to perform in the disclosed invention. It is to be understood that the value to which the modifier "about" or “approximately” refers is itself also specifically, and preferably, disclosed.

Whereas the terms “one or more” or “at least one”, such as one or more or at least one member(s) of a group of members, is clear per se, by means of further exemplification, the term encompasses inter alia a reference to any one of said members, or to any two or more of said members, such as, e.g., any >3, >4, >5, >6 or >7 etc. of said members, and up to all said members.

All references cited in the present specification are hereby incorporated by reference in their entirety. In particular, the teachings of all references herein specifically referred to are incorporated by reference.

Unless otherwise defined, all terms used in disclosing the invention, including technical and scientific terms, have the meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. By means of further guidance, term definitions are included to better appreciate the teaching of the present invention.

In the following passages, different aspects of the invention are defined in more detail. Each aspect so defined may be combined with any other aspect or aspects unless clearly indicated to the contrary. In particular, any feature indicated as being preferred or advantageous may be combined with any other feature or features indicated as being preferred or advantageous.

Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment, but may. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner, as would be apparent to a person skilled in the art from this disclosure, in one or more embodiments. Furthermore, while some embodiments described herein include some but not other features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the invention, and form different embodiments, as would be understood by those in the art. For example, in the appended claims, any of the claimed embodiments can be used in any combination.

According to one aspect the present invention provides a dental component (“dental component” herein) having an apical end and a coronal end. The dental component is disposed with an attachment portion extending from the apical end in a coronal direction along an attachment portion central longitudinal axis and configured for connection to a dental implant component and a prosthetic connection portion extending from the coronal end in an apical direction along a prosthetic connection portion central longitudinal axis and configured for connection to a prosthetic component. The prosthetic connection portion comprises a lateral outer surface, comprising one or more roughened area each provided with a regular pattern of microstructures, the regular pattern of microstructures covering the entire surface of the one or more roughened area.

The microstructures increase the surface roughness of the one or more roughened area, thereby enhancing adhesion of cement to the dental component. The regular pattern of microstructures can be produced by, e.g. lithography, micro-knurling or laser marking. These processes, and particularly use of a laser to create the microstructures, enables fast, precise production of a homogenous roughened surface, this surface being capable of exact replication on multiple different dental components. This leads to a more consistent and reliable retention force than can be achieved by individual sandblasting of components. Further, as the roughened surface can be applied very precisely, and without the use of a potential contaminant, the production steps are simplified. Laser marking also allows the straightforward formation of a dental component having one or more roughened area and one or more unroughened area, which can be used to improve both the fitting and cementing between parts, as will be described further below.

In accordance with conventional dental terminology, “apical” refers to the direction towards the bone and “coronal” to the direction towards the occlusal surface of the teeth. Therefore, the “apical end” of a component is the end which, in use, is directed towards or into the jawbone and the “coronal end” is which, in use, is directed towards or into the oral cavity. “Central longitudinal axis” (A-A’) as used herein is an axis along which the dental component, or part of the dental component, extends from its apical end to its coronal end. It is often co-axial, in use, with an axis around which torque is applied to the dental implant in order to achieve linear movement of the dental implant.

“Coronal end” as used herein refers to the terminal end of a component or part of a component in the coronal direction.

“Apical end” as used herein refers to the terminal end of a component or part of a component in the apical direction.

“Transverse” as used herein means across a plane perpendicular to the central longitudinal axis (A-A’).

“Medial” as used herein means towards the central longitudinal axis (A-A’) in a direction having a radial component, or having mainly a radial component.

“Lateral” as used herein means away from the central longitudinal axis (A-A’) in a direction having a radial component, or having mainly a radial component.

“Longitudinal” as used herein means in a direction along or parallel to the central longitudinal axis (A-A’).

“Lateral outer surface” refers to an outer surface of a component, or part of a component, that is disposed lateral of the central longitudinal axis (A-A’). Where the component is cylindrical (hollow or solid), the lateral outer surface is the outer cylindrical surface.

“Attachment portion” as used herein is a longitudinal section of the dental component configured for connecting with an apically located dental implant component such as an implant or abutment. “Prosthetic connection portion” as used herein is a longitudinal section of the dental component configured for connecting with a prosthetic component, such as a crown, bridge, coping, denture etc.

The components mentioned herein (dental component, prosthetic component, dental implant component, implant, or abutment as well as an assembly of said components) each have an apical direction, a coronal direction, a medial direction, a lateral direction, and a central longitudinal axis (A-A’). It is understood that other components (e.g. threaded fastener) of an assembly of said components are also disposed with the aforementioned directional indicators.

The regular pattern of structures formed on the one or more roughened area are microstructures, meaning that the length and/or width of each microstructure is less than 75 microns, preferably less than 50 microns. Such microstructures cannot be individually detected by the human eye, which instead sees a matt surface similar to that obtained by sand blasting. When viewed under magnification however, the two surface types are easily distinguished. A sandblasted surface comprises a plurality of irregular depressions, formed on the surface through deformation and ablation of the surface by the impact of particles. The surface of the present invention in contrast comprises a regular, repeated pattern of structures formed by, e.g., the application of a laser to the surface.

The regular pattern of microstructures covers the entire surface of the one or more roughened area. This means that the pattern is repeated uniformly across the roughened area such that there are no discontinuities in the pattern within the roughened area.

The roughness of a surface can be measured according to ISO25178. According to this method, a 3D surface topography is obtained by electromagnetic interaction with the skin of a workpiece (implant, abutment, etc.). In other words, a light is shone on the surface of a component and the reflection of this light is measured, providing a 3D topography measurement. This results in S-value roughness parameters.

Preferably each one or more roughened area has an arithmetical mean height (Sa) value in a range of 0.5 to 2 microns, more preferably 0.6 to 1 .8 microns. More specifically, each regular pattern of microstructures preferably has an arithmetical mean height (Sa) in a range of 0.5 to 2 microns, more preferably 0.6 to 1 .8 microns.

Additionally, each one or more roughened area preferably has a maximum height (Sz) of between 2.5 and 11 microns. More specifically, each regular pattern of microstructures preferably has a maximum height (Sz) of between 2.5 and 11 microns. This range is preferred as high Sz values could lead to high peaks on the surface interfering with the correct fitting of the prosthesis over the prosthetic connection portion.

In the case of a sandblasted surface, a high Sz value is less likely to be a problem, as the entire outer surface is reduced by the sandblasting. This is not the case in the laser marking or micro-knurling process and hence Sz is a more important parameter and should not be allowed to be too large in case this interferes with the fit of the coping.

In addition, a high Sz value may result in deep valleys, which could weaken the prosthetic connection portion.

Additionally or alternatively, each one or more roughened area preferably has a skewness (Ssk) of between -0.4 and 0.5. More specifically, each regular pattern of microstructures preferably has a skewness (Ssk) of between -0.4 and 0.5.

In a particularly preferred embodiment, each one or more roughened area has a surface topography defined by an arithmetical mean height (Sa) of between 0.5 and 2 microns, more preferably 0.6 and 1.8 microns, a maximum height (Sz) of between 2.5 and 11 microns and a skewness (Ssk) of between -0.4 and 0.5.

More specifically, each regular pattern of microstructures preferably has a surface topography defined by an arithmetical mean height (Sa) of between 0.5 and 2 microns, more preferably 0.6 and 1.8 microns, a maximum height (Sz) of between 2.5 and 11 microns and a skewness (Ssk) of between -0.4 and 0.5. Such surface topographies have been demonstrated to provide an equivalent or greater pull off force (retention) than is achieved by abutments having a sandblasted surface.

Skewness (Ssk) measures the symmetry of the variation of a surface about its mean plane. A Gaussian surface, having a symmetrical shape for the height distribution, has a skewness of 0. A surface with a predominant plateau and deep recesses will tend to have a negative skewness, whereas a surface having a number of peaks above average will tend to have a positive skewness.

A positive skewness therefore provides a more protruding surface than a negative skewness value. While good retention can be achieved with negative Ssk surfaces, these surfaces were also observed to generally have higher Sz values, meaning that the maximum peak and valley heights were larger in these surfaces than in good-performing positive Ssk surfaces. As discussed above, large peak heights are disadvantageous as they may interfere with the fit of the prosthesis over the prosthetic connection portion, while deep valleys may weaken the prosthetic connection portion.

Therefore, preferably each one or more roughened area has a surface topography defined by a skewness (Ssk) of greater than or equal to zero and a maximum height (Sz) of between 2.5 and 7 microns. More preferably each one or more roughened area has a surface topography defined by a skewness (Ssk) of greater than zero and a maximum height (Sz) of between 2.5 and 7 microns. In a preferred embodiment the skewness (Ssk) is between 0 and 0.4, more preferably the skewness (Ssk) is >0 and <0.4. Preferably, in addition to any or all of these preferred values, the surface topography is further defined by an arithmetical mean height (Sa) of between 0.5 and 2 microns, more preferably 0.6 and 1 .8 microns.

More specifically each regular pattern of microstructures preferably has a surface topography defined by a skewness (Ssk) of greater than or equal to zero and a maximum height (Sz) of between 2.5 and 7 microns. Most preferably the skewness (Ssk) is between 0 and 0.4. Preferably the surface topography is further defined by an arithmetical mean height (Sa) of between 0.5 and 2 microns, more preferably 0.6 and 1.8 microns. More specifically each regular pattern of microstructures preferably has a surface topography defined by a skewness (Ssk) of greater than zero and a maximum height (Sz) of between 2.5 and 7 microns. Most preferably the skewness (Ssk) is >0 and <0.4. Preferably the surface topography is further defined by an arithmetical mean height (Sa) of between 0.5 and 2 microns, more preferably 0.6 and 1 .8 microns.

The above preferred ranges of Ssk and Sz values are considered to provide a good retention while preventing the potential disadvantages of high peaks and deep valleys.

The above S value parameters, namely arithmetical mean height (Sa), skewness (Ssk) and maximum height (Sz), are measured according to ISO 25178 using the following settings: Confocal microscope with 532 nanometer wavelength and 20 x objective least square polynomial of 3rd degree form removal (F-operator)

2.5 pm S filter (gaussian) to remove small scale lateral components from the surface 250 pm L filter (gaussian) to remove large scale lateral components from the surface threshold 2.5% - 97.5% to exclude outlier peaks resulting from measurement artefacts.

While these settings have been found to enable an accurate capture and isolation of the core topography of the one or more roughened area important for the functionality (retention), a person skilled in the art of 3D topography measurement may apply their knowledge to adjust these settings as required in order to capture and isolate the topography of the one or more roughened area.

These measurements may be carried out, for example, using a Sensofar S neox machine.

The roughness of a surface can also be measured along a 2D surface profile. This results in R-value roughness parameters.

Additionally or alternatively to the above preferred S-values therefore the one or more roughened area may be characterized by R-value parameters. According to a preferred embodiment each one or more roughened area has an arithmetical mean deviation of the assessed profile (Ra) value in a range of 0.5 to 2 microns, more preferably 0.6 to 1 .8 microns.

More specifically, each regular pattern of microstructures preferably has an arithmetical mean deviation of the assessed profile (Ra) value in the range of 0.5 to 2 microns, more preferably 0.6 to 1.8 microns.

Additionally, the maximum height of the profile (Rz) of each one or more roughened area and/or each regular pattern of microstructures is preferably between 1 and 12 microns, more preferably between 3 and 10 microns. In a similar manner to high Sz values, a high Rz value could lead to high peaks interfering with the correct fitting of the prosthesis over the prosthetic connection portion, or to deep valleys weakening the prosthetic connection portion.

In a particularly preferred embodiment each one or more roughened area has a surface topography defined by an arithmetical mean deviation of the assessed profile (Ra) of between 0.5 and 2 microns and a maximum height of the profile (Rz) of between 1 and 12 microns, more preferably defined by an arithmetical mean deviation of the assessed profile (Ra) of between 0.6-1 .8 microns and a maximum height of the profile e (Rz) of between 3-10 microns.

More specifically each regular pattern of microstructures preferably has a surface topography defined by an arithmetical mean deviation of the assessed profile (Ra) of between 0.5 and 2 microns and a maximum height of the profile (Rz) of between 1 and 12 microns, more preferably defined by an arithmetical mean deviation of the assessed profile (Ra) of between 0.6-1 .8 microns and a maximum height of the profile (Rz) of between 3-10 microns.

The above R value parameters, namely the arithmetical mean deviation of the assessed profile (Ra) and maximum height of the profile (Rz), are measured according to ISO-21290 with the following settings: upper cut-off (Ls) of 2.5 microns, lower cut-off (Lc) of 250 microns, evaluation length of 1.5 mm, measurement speed of 0.5mm/s, tracer tip radius of 2 microns.

While these settings have been found to enable an accurate capture and isolation of the profile of the one or more roughened area important for the functionality (retention), a person skilled in the art of surface measurement may apply their knowledge to adjust these settings as required in order to capture and measure the profile of the one or more roughened area.

The above R-value parameters can be obtained, for example, using a DIAVITE MICRO VHF Rugosimeter. In particular, the R-value parameters can be measured on this machine using the standard machine settings when an evaluation length of 1 ,5mm is selected and a tracer tip radius of 2 microns is used.

The microstructures within each one or more roughened area can be any shape. For example, the microstructures may be grooves, ridges, dimples, beads, depressions, protrusions etc. Any regular pattern of microstructures can be used. Preferably, adjacent microstructures within each regular pattern are positioned within 75 microns, more preferably within 50 microns of each other. In this way, the one or more roughened area is densely packed with microstructures in order to improve cement retention. Preferably the distance between adjacent microstructures is less than the width of the microstructures themselves.

Each regular pattern of microstructures may comprise a plurality of repeated helical paths, a plurality of repeated closed circumferential paths, a plurality of repeated open circumferential paths, a plurality of repeated longitudinal paths, or a combination of two or more of these (at least partially overlayed). A path is formed by a single microstructure, e.g. a ridge or a groove, in which case the path is a continuous path, or a plurality of discrete microstructures, e.g. dimples, beads, protrusions, depressions, or the space between a plurality of discrete microstructures. In these cases the path is a discontinuous path. The regular pattern may be formed by a plurality of continuous paths, discontinuous paths, or a combination of continuous and discontinuous paths. By helical path, it is meant that the path of the microstructure(s) has a rise that causes the path to both extend circumferentially and longitudinally. The helical path may cover a portion of one turn around the lateral outer surface, or may cover at least one (e.g. 1 , 1.5, 2) turn around the lateral outer surface. The regular pattern may be formed by a single helical path or a plurality of repeated helical paths.

By repeated, it is meant that at least some of the helical paths are aligned in parallel, forming an aligned (side-by-side) stack of neighbouring helices. Where all of the helical paths are aligned in parallel, the stack has a multi start threaded form. According to one aspect, some of the helical paths are aligned in parallel in one orientation, and some of the helical paths are aligned in parallel in another orientation. Where the differently oriented helical paths cross, it gives rise to a crisscross form of helical paths in the stack. It is appreciated that the repeated helical paths may be combined (at least partially overlayed) with a plurality of repeated closed circumferential paths, and/or with a plurality of repeated open circumferential paths and/or with a plurality of repeated longitudinal paths.

By closed circumferential path, it is meant that the path of the microstructure(s) extends circumferentially around the lateral outer surface in a closed loop. The closed loop may be planar and disposed in a plane perpendicular to the prosthetic connection portion central longitudinal axis. Alternatively, the closed loop may be planar and disposed in a plane at an oblique angle to the prosthetic connection portion central longitudinal axis. Alternatively, the closed loop may not be planar.

By repeated, it is meant that at least some of the closed circumferential paths are aligned in parallel, forming a (side-by-side) stack of longitudinally neighbouring closed circumferential paths. All of the closed circumferential paths may be aligned in parallel. Alternatively, some of the closed circumferential paths are aligned in parallel in one direction, and some of the closed circumferential paths are aligned in parallel in another direction, giving rise to a crisscross form of closed circumferential paths in the stack. It is appreciated that the plurality repeated closed circumferential paths may be combined (at least partially overlayed) with a plurality of repeated open circumferential paths, and/or a plurality of repeated helical paths and/or with a plurality of repeated longitudinal paths. By open circumferential path, it is meant that the path of the microstructure(s) extends partially circumferentially around the lateral outer surface in an open loop. The open loop may be planar and disposed in a plane perpendicular to the prosthetic connection portion central longitudinal axis. Alternatively, the open loop may be planar and in a plane at an oblique angle to the prosthetic connection portion central longitudinal axis. Alternatively, the open loop may not be planar.

By repeated, it is meant that at least some of the open circumferential paths are aligned in parallel, forming a (side-by-side) stack of longitudinally neighbouring open circumferential paths. All of the open circumferential paths may be aligned in parallel. Alternatively, some of the open circumferential paths are aligned in parallel in one direction, and some of the open circumferential paths are aligned in parallel in another direction, giving rise to a crisscross form of open circumferential paths in the stack. It is appreciated that the plurality of repeated open circumferential paths may be combined (at least partially overlayed) with a plurality of repeated closed circumferential paths, and/or a plurality of repeated helical paths and/or with a plurality of repeated longitudinal paths.

By longitudinal path, it is meant that the path of the microstructure(s) extends parallel to the prosthetic connection portion central longitudinal axis (A-A’). Each longitudinal path may cover a portion of a length of the prosthetic connection portion, or may cover a full length of the prosthetic connection portion.

By repeated, it is meant that the longitudinal paths are aligned in parallel. The plurality of adjacently-arranged longitudinal paths extend (stack) circumferentially. It is appreciated that the repeated longitudinal paths may be combined (at least partially overlayed) with a plurality of repeated helical paths and/or with a plurality of repeated closed circumferential paths, and/or with a plurality of repeated open circumferential paths.

As discussed above, the paths, whether continuous or discontinuous, within the regular pattern may all have the same orientation, e.g. all paths may extend circumferentially and in planes perpendicular to the prosthetic connection portion central longitudinal axis.

Alternatively, the regular pattern may contain two or more sets of paths, the sets having different orientations to each other. For example, a grid pattern may be formed by a first set of longitudinal paths extending parallel to the prosthetic connection portion central longitudinal axis and a second set of closed and/or open paths which extend around the circumference of the prosthetic connection portion in planes perpendicular to the prosthetic connection portion central longitudinal axis. Alternatively, two sets of paths can extend around the circumference of the prosthetic connection portion at oblique angles to the prosthetic connection portion central longitudinal axis, the angles of each set being offset, e.g. by 90°, from one another.

In a particularly preferred embodiment, each regular pattern of microstructures comprises an array of discrete microstructures, the microstructures being arranged in a series of rows, each row preferably being located in a plane perpendicular to the prosthetic connection portion central longitudinal axis. An array of this type provides a large, even coverage of microstructures within each one or more roughened area. The microstructures may be protrusions or depressions and may be any shape but preferably have a circular footprint relative to the lateral outer surface. Preferably the array is an array of depressions. Such depressions are easy to produce using, e.g., a laser.

Preferably the rows are arranged as a series of offset rows. The offset nature of the rows means that the discrete microstructures, preferably depressions, of each adjacent row are not in alignment with one another, thus forming a hexagonal pattern.

Each regular pattern of microstructures may be produced by any process suitable for removal or deformation of material on the microscale mentioned herein, such as microknurling or laser marking. Preferably each regular pattern of microstructures is produced by laser marking. The laser marking removes and/or alters a part of the lateral outer surface of the prosthetic connection portion. The laser marking can be achieved, for example, using a femtolaser, picolaser or a nanolaser. The marking can be achieved using a one or multi- step process. For example, the regular pattern of microstructures can be applied in a first step and in a second step the regular pattern of microstructures can be modified in order to change one or more characteristic of the microstructures. In one preferred embodiment, the one or more roughened area further comprises a plurality of regularly spaced macrogrooves, the regular pattern of microstructures covering the entire surface of the one or more roughened area inclusive of the plurality of macrogrooves. The regularly spaced macrogrooves may be present over a part of or all of a roughened area.

The provision of the plurality of regularly spaced macrogrooves increases the overall roughness of the one or more roughened area, as well as providing a structure for accommodating cement. The regular pattern of microstructures meanwhile provides a roughened surface over the entire roughened area.

The plurality of regularly spaced macrogrooves may each follow a closed or open circumferential path and be disposed in a plane perpendicular to the prosthetic connection portion central longitudinal axis or in a plane at an oblique angle to this. All of the plurality of regularly spaced macrogrooves may be aligned in parallel. However, preferably the plurality of regularly spaced macrogrooves is arranged in a lattice structure. A typical lattice structure has a crisscross pattern, forming a regular pattern of square, rectangular or diamond shapes. In a preferred embodiment therefore, one set of regularly spaced macrogrooves are aligned in parallel in one direction, and a second set of regularly spaced macrogrooves are aligned in parallel in another direction, the first and second sets forming a lattice structure of macrogrooves.

In contrast to the microstructures, the plurality of regularly spaced macrogrooves of the one or more roughened area are visible to the human eye without magnification. Preferably each macrogroove of the plurality of regularly spaced macrogrooves has a width greater than 90 microns, more preferably between 90 and 150 microns.

The plurality of regularly spaced macrogrooves are preferably spaced within 400 microns of one another, more preferably within 300 microns of one another and most preferably within 200 microns of one another. When the macrogrooves of the plurality of regularly spaced macrogrooves are arranged in a lattice structure these preferred spacings refer to the distance between adjacent macrogrooves within each set. The plurality of regularly spaced macrogrooves increases the surface roughness of the one or more roughened area. Preferably, the one or more roughened area has an arithmetical mean deviation of the assessed profile (Ra) of between 2.5 and 6 microns when the measurement sample includes one or more of the macrogrooves. The preferred surface roughness parameters (R-value and/or S-value) given above in respect of the regular pattern of microstructures are also applicable in embodiments featuring a plurality of regularly spaced macrogrooves when the regular pattern of microstructures is measured in isolation from the regularly spaced macrogrooves.

The plurality of regularly spaced macrogrooves may be produced by any process suitable for removal or deformation of material from a surface, such as knurling or laser marking. Preferably the macrogrooves are produced by laser marking. The laser marking removes or alters a part of the lateral outer surface of the prosthetic connection portion. The laser marking can be achieved, for example, using a nanolaser, picolaser or a femtolaser. The macrogrooves may be introduced as part of a multistep process. For example, the plurality of regularly spaced macrogrooves may be applied in a first step, and in a second step the regular pattern of microstructures may be applied, and in an optional third step the surface may be modified in order to change one or more characteristic of the microstructures.

As mentioned above, the regular pattern of microstructures covers the entire surface of the one or more roughened area inclusive of the plurality of regularly spaced macrogrooves. In order to achieve this, the regular pattern of microstructures is typically added to the lateral outer surface of the prosthetic connection portion after the plurality of regularly spaced macrogrooves have been introduced.

In one preferred embodiment the one or more roughened area comprises a plurality of regularly spaced macrogrooves, said macrogrooves being arranged in a lattice structure, the regular pattern of microstructures covering the entire surface of the one or more roughened area inclusive of the plurality of regularly spaced macrogrooves, the regular pattern of microstructures comprising a plurality of repeated paths.

In a particularly preferred embodiment, the one or more roughened area comprises a plurality of regularly spaced macrogrooves arranged in a lattice structure, one set of the regularly spaced macrogrooves being aligned in parallel in one direction, and a second set of the regularly spaced macrogrooves being aligned in parallel in another direction, each macrogroove of the plurality of macrogrooves extending at an oblique angle to an axis on the lateral outer surface parallel to the prosthetic connection portion central longitudinal axis (A-A’), and the one or more roughened area further comprising a regular pattern of microstructures, the regular pattern of microstructures covering the entire surface of the one or more roughened area inclusive of the plurality of macrogrooves, the regular pattern comprising a plurality of repeated paths. Most preferably, the regular pattern of microstructures comprises a plurality of closed and/or open circumferential paths arranged adjacent and parallel to one another and preferably extending perpendicular to the central longitudinal axis of the prosthetic connection portion.

In some embodiments, the one or more roughened area, preferably each and every roughened area, are provided solely with a regular pattern of microstructures. Alternatively, the one or more roughened area, preferably each and every roughened area, may further comprise the above described plurality of regularly spaced macrogrooves for increasing the roughness of the one or more roughened area and hence increase cement retention.

While it is possible for different roughened areas to comprise different patterns of microstructures and/or different patterns of regularly spaced macrogrooves, it is preferred that each and every roughened area comprises the same regular pattern of microstructures and, where present, the same pattern of regularly spaced macrogrooves.

According to the present invention the lateral outer surface of the prosthetic connection portion comprises one or more roughened area provided with a regular pattern of microstructures. The entire surface of the one or more roughened area is covered by the regular pattern of microstructures. A roughened area is a continuous, unbroken area provided with a regular pattern of microstructures. A continuous area may surround, either fully or partially, a non-roughened area that does not contain a regular pattern of microstructures.

The lateral outer surface of the prosthetic connection portion may comprise one single roughened area. The single roughened area may extend over the whole of the lateral outer surface of the prosthetic connection portion such that the whole lateral outer surface is provided with the regular pattern of microstructures. Alternatively, the single roughened area may extend only over a part of the lateral outer surface of the prosthetic connection portion.

The lateral outer surface of the prosthetic connection portion may instead comprise two or more roughened areas. The roughened areas can be contiguous, or they may be spatially separated, or they may partially overlap. Within any area of overlap the regular pattern of microstructures of one roughened area is overlayed by the regular pattern of microstructures of a second roughened area. This can obscure or alter the regular patterns as well as affect the surface roughness values in this area of overlap. Therefore, the above-described preferred characteristics of the one or more roughened area and regular pattern of microstructures are not necessarily applicable within an area of overlap, but refer to each roughened area and regular pattern of microstructures in isolation, namely, where there is no overlap.

Preferably, where an area of overlap between roughened areas is present, this extends over a width of no more than 0.5mm, more preferably over a width of no more than 0.3mm and most preferably over a width of less than 0.25mm.

In preferred embodiments however, there is no overlap between adjacent roughened areas. This prevents any inadvertent weakening of the component walls, which may occur due to excess material removal in the area of overlap. In addition, the relatively large variations in height which can occur in any area of overlap can lead to local stress concentrations.

In order to ensure a good coverage of the prosthetic connection portion it is further preferred that the maximum separation distance between at least one pair of adjacent nonoverlapping roughened areas is less than 0.5 mm, more preferably less than 0.25 mm. In certain preferred embodiments, all adjacent non-overlapping roughened areas of the prosthetic connection portion have a maximum separation distance of less than 0.5 mm, more preferably less than 0.25 mm. A separation distance between a pair of adjacent nonoverlapping roughened areas is typically measured along the lateral outer surface between a first peripheral point of one roughened area and a second peripheral point on the adjacent roughened area, the second point being selected to provide the smallest path to the first peripheral point.

In order to provide a good cement retention, it is preferred that in aggregate the one or more roughened area covers at least 50% of the lateral outer surface of the prosthetic connection portion, more preferably at least 75% of the lateral outer surface of the prosthetic connection portion.

According to a preferred embodiment, one or more roughened area extends to the coronal end of the lateral outer surface of the prosthetic connection portion. Additionally or alternatively, one or more roughened area preferably extends to within 2mm, more preferably to within 1 mm, of the apical end of the lateral outer surface of the prosthetic connection portion.

Preferably one or more roughened area covers the full circumferential extent of the coronal end of the lateral outer surface.

According to the present invention, the lateral outer surface of the prosthetic connection portion comprises one or more roughened area. Preferably the one or more roughened area of the present invention is located only on the prosthetic connection portion. In other words, any and all other portions of the dental component do not comprise one or more roughened area in accordance with the present invention. In particular, the attachment portion does not comprise one or more roughened area in accordance with the present invention. In this way, the attachment portion, which is configured for connection to a dental implant component, remains precisely shaped for creating a sealed, and in some cases rotationally fixed, connection to the dental implant component.

As described above, a single roughened area may extend over the whole of the lateral outer surface of the prosthetic connection portion such that the whole lateral outer surface is provided with a regular pattern of microstructures. However, in preferred embodiments, some areas of the lateral outer surface of the prosthetic connection portion remain free of microstructures. In other words, the lateral outer surface of the prosthetic connection portion preferably comprises one or more unroughened area which is devoid of the above described regular pattern of microstructures.

The prosthetic connection portion may comprise one or more additional structural feature, as will be described below. In preferred embodiments, one or more of these additional structural features is located in an unroughened area of the prosthetic connection portion.

The lateral outer surface of the prosthetic connection portion may comprise one or more laterally (e.g. radially) extending indexing protrusion (known as a “prosthetic indexing protrusion” herein). See, for instance, FIGs. 4, 4A and 4B. Such indexing protrusion(s) is configured to prevent axial rotation (around the prosthetic connection portion central longitudinal axis) of the prosthetic component relative to the dental component when the prosthetic component is engaged with the one or more indexing protrusion. Such indexing protrusion(s) is further configured for longitudinal slidable engagement with a complementary receiving opening in the prosthetic component.

When the lateral outer surface comprises such one or more indexing protrusion it is preferred that each one or more indexing protrusion(s) is located outside the one or more roughened area. In other words, the one or more prosthetic indexing protrusion is preferably located in an unroughened area of the lateral outer surface of the prosthetic connection portion.

By locating the one or more prosthetic indexing protrusion in an unroughened area, a precise fit with the prosthetic component can be ensured, since no surface of the protrusion is removed or distorted to provide the regular pattern of microstructures or plurality of regularly spaced macrogrooves. Thus, a high level of rotational security is provided between the components, which are further fixed more effectively by cement interacting with the one or more roughened areas.

Additionally or alternatively, the lateral outer surface of the prosthetic connection portion may comprise one or more transverse macrogroove, said one or more macrogroove being located in a plane perpendicular to the prosthetic connection portion central longitudinal axis. It may be known herein as a “transverse macrogroove”. When a plurality of such transverse macrogrooves is present, these grooves are located at discrete axial locations. The one or more transverse macrogroove may extend partially around the circumference of the prosthetic connection portion, however preferably the one or more transverse macrogroove is an annular macrogroove, extending around the full circumference of the prosthetic connection portion. When the lateral outer surface of the prosthetic connection portion comprises one or more of the above described laterally extending prosthetic indexing protrusions, the one or more transverse macrogroove is located coronally of said indexing protrusion(s).

A macrogroove is discernable to the human eye (see, for instance, FIGs. 6 and 6A). The one or more transverse macrogroove forms an axial height indicator and assists the user in shortening the dental component to a desired height when required.

Preferably the one or more transverse macrogroove has a width of 0.1 mm or greater, more preferably between 0.15 and 0.3 mm. When a plurality of such macrogrooves is present the grooves are preferably equally axially spaced from each other by a distance of between 0.5 and 2mm, most preferably 1mm. Preferably the lateral outer surface of the prosthetic connection portion comprises between one and four transverse macrogrooves.

The one or more transverse macrogroove may be introduced by, e.g., laser marking and/or milling.

When the lateral outer surface comprises such one or more transverse macrogroove it is preferred that each one or more transverse macrogroove is located outside the one or more roughened area. In other words, the one or more transverse macrogroove is preferably located in an unroughened area of the lateral outer surface of the prosthetic connection portion. Placing the one or more transverse macrogroove in an unroughened area improves the visibility of these grooves to the user.

Alternatively, in certain embodiments, one or more transverse band of unroughened area interposed between roughened areas may act as one or more height indicator without the need for any transverse macrogrooves being present. Instead, the visual contrast between the roughened and unroughened areas is enough to provide a visual indication to the user. In such embodiments the one or more band of unroughened area can have any or all of the location, dimensions, spacings and quantities listed above in relation to the transverse macrogroove(s).

However, usually when it is desired to create one or more height indicator on the dental component it is preferred to provide these in the form of transverse macrogrooves as these grooves further assist in the cutting of the prosthetic connection portion at the indicated height(s).

Additionally or alternatively, the lateral outer surface of the prosthetic connection portion may comprise a coronally facing annular surface, said coronally facing annular surface defining the apical end of the prosthetic connection portion. This surface is configured to contact the apical end of the prosthetic component, thus providing a stop surface and load bearing surface. The coronally facing annular surface may taper radially outwards in the apical or coronal direction. However, preferably at least the radially outermost region of the coronally facing annular surface lies in a plane perpendicular to the prosthetic connection portion central longitudinal axis.

The coronally facing annular surface extends laterally beyond the remainder of the prosthetic connection portion. In other words, the coronally facing annular surface has a greater radius than the remainder of the lateral outer surface of the prosthetic connection portion.

When the lateral outer surface comprises such a coronally facing annular surface it is preferred that this surface is located outside the one or more roughened area. In other words, the coronally facing annular surface is preferably located in an unroughened area of the lateral outer surface of the prosthetic connection portion.

In this way, the coronally facing annular surface can have a machined, smooth surface in order to provide a good seal between the dental component and the prosthetic component. It has been found that, in order to ensure the strength of the component, it is preferable that the apical most end of the one or more roughened area closest to the coronally facing annular surface is located at least 0.3 mm coronal of the coronally facing annular surface, more preferably at least 0.5 mm coronal of this surface. In particular, it is preferable that an unroughened area of the lateral surface extends from an apical end of the prosthetic connection surface about the full circumference of the prosthetic connection surface to a distance of at least 0.3 mm, more preferably at least 0.5 mm coronal of the coronally facing annular surface. This distance is measured parallel to the longitudinal axis between a first point that is a peripheral point at the apical end of the roughened area adjacent to the coronally facing annular surface, and a second point that is a medial-most point of the coronally facing annular surface. In particularly preferred embodiments one or more roughened area extends to within 1.5 mm - 0.3 mm of the coronally facing annular surface, more preferably to within 0.8 mm - 0.4 mm of the coronally facing annular surface, wherein the area between the one or more roughened area and the coronally facing surface has a machined, unroughened surface. This ensures a good coverage of roughened area without weakening the component.

In a preferred embodiment the lateral outer surface of the prosthetic connection portion comprises a coronally facing annular surface, said coronally facing annular surface defining the apical end of the prosthetic connection portion, the lateral outer surface further comprising a circular cylindrical and/or conical surface located coronally of the coronally facing annular surface. Preferably this circular cylindrical and/or conical surface comprises three or more circumferentially spaced roughened areas, each area being provided with an identical pattern of microstructures, the adjacent roughened areas being contiguous or partially overlapping with one another. This eases production of the roughened areas, as the material-removal step (e.g. laser marking) can be applied to the circular cylindrical and/or conical surface at a fixed number of discrete rotational orientations. For example, the circular cylindrical and/or conical surface may comprise three, four or five partially overlapping roughened areas. Each area of overlap is preferably no more than 0.5mm, preferably no more than 0.3mm, preferably no more than 0.25mm in width as measured around the circumference of the prosthetic connection portion. Alternatively, the circular cylindrical and/or conical surface may comprise a plurality (e.g. three, four or five) of adjacent, non-overlapping roughened areas. The adjacent nonoverlapping roughened areas of the plurality are arranged to have a pairwise maximum separation distance of preferably no more than 0.5 mm, preferably no more than 0.25 n

Preferably the circular cylindrical and/or conical surface is a circular cylindrical surface.

In the same or an alternative preferred embodiment, the lateral outer surface of the prosthetic connection portion comprises a coronally facing annular surface, said coronally facing annular surface defining the apical end of the prosthetic connection portion, the lateral outer surface further comprising, coronal of the coronally facing annular surface, one or more laterally extending prosthetic indexing protrusion and, coronal of the one or more prosthetic indexing protrusion, one or more transverse macrogroove, each of the coronally facing annular surface, the one or more prosthetic indexing protrusion and the one or more transverse macrogroove being located outside of the one or more roughened area. In other words, the coronally facing annular surface, the one or more prosthetic indexing protrusion and the one or more transverse macrogroove are each located in unroughened areas of the lateral outer surface of the prosthetic connection portion, such that the coronally facing annular surface, the one or more prosthetic indexing protrusion and the one or more transverse macrogroove have a roughness less than the one or more roughened area. Preferably one or more roughened area extends from the coronal end of the lateral outer surface and in aggregate the one or more roughened area covers at least 90% of the lateral outer surface of the prosthetic connection portion exclusive of the coronally facing annular surface, the one or more prosthetic indexing protrusion and the one or more transverse macrogroove. In other words, the roughened area(s) cover(s) substantially the whole lateral outer surface of the prosthetic connection portion apart from the coronally facing annular surface, the one or more prosthetic indexing protrusion and one or more transverse macrogroove.

Preferably one or more roughened area extends in aggregate over the lateral outer surface from the coronal end of the lateral outer surface to within 1 .5 mm - 0.3 mm, more preferably to within 0.8 mm - 0.4 mm of the coronally facing annular surface exclusive of the one or more prosthetic indexing protrusion and the one or more transverse macrogroove. In other words, the roughened area(s) cover(s) substantially the whole lateral outer surface of the prosthetic connection portion apart from the one or more prosthetic indexing protrusion, the one or more transverse macrogroove, and the apical most area of the prosthetic connection portion, which includes the coronally facing annular surface and lateral outer surface directly coronal of the coronally facing annular surface up to a distance of 0.3 mm - 1 .5 mm (more preferably 0.4 mm - 0.8 mm) from coronally facing annular surface.

The dental component of the present invention may be any component which in use is directly cemented to a dental prosthetic component and which is connected to an underlying dental implant component. In other words, dental component of the present invention may be any component configured for directly cementing to a dental prosthetic component and for connecting to an underlying dental implant component.

For example, the dental component can be a dental abutment, the abutment comprising an attachment portion for connection to a dental implant component that is a dental implant. The dental component may alternatively be a coping, the coping comprising an attachment portion for connection to a dental implant component that is a dental abutment.

In both embodiments the dental component preferably comprises an open channel extending from the apical end to the prosthetic connection portion of the component. This enables a threaded fastener (e.g. screw) to be accommodated in the component to fasten this to the underlying dental implant component. Alternatively however, the dental component may be configured for cementing to the underlying dental implant component, in which case no open channel is necessary.

According to the present invention, the dental component is disposed with an attachment portion for connection to a dental implant component and a prosthetic connection portion for connection to a prosthetic component. By connection, it is meant that the respective parts are capable of at least engaging with each other. It also means that the respective parts are capable of at least fittingly attaching to each other, for instance, using cement between the prosthetic connection portion and prosthetic component. According to the present invention the dental component comprises an attachment portion extending from the apical end of the dental component in a coronal direction. The attachment portion extends along an attachment portion central longitudinal axis which can be coaxial with or angled in relation to the prosthetic connection portion central longitudinal axis.

The attachment portion may comprise a cavity for housing the coronal portion of a dental implant component. Such an attachment portion is particularly preferred when the dental component is a coping, in which case the attachment portion preferably comprises a cavity for housing the coronal portion of a dental abutment. However, such an attachment portion can also be used when the dental component is an abutment, in which case the attachment portion preferably comprises a cavity for housing the coronal portion of a dental implant.

When the attachment portion comprises a cavity for housing the coronal portion of a dental implant component, the attachment portion may at least partially overlap with the prosthetic connection portion. For example, the medial inner surface formed by the cavity may extend within the lateral outer surface of the prosthetic connection portion. In such embodiments the attachment portion central longitudinal axis is typically coaxial to the prosthetic connection portion central longitudinal axis.

Alternatively, the attachment portion may comprise a post portion for insertion into the bore of a dental implant component. Such an attachment portion is particularly preferred when the dental component is an abutment, in which case the attachment portion preferably comprises a post portion for insertion into the bore of a dental implant. In such embodiments the post portion is located entirely apical of the prosthetic connection portion.

Irrespective of whether the attachment portion comprises a cavity or a post portion, the attachment portion may comprise an indexing section having a non-circular-symmetric cross-section in a plane perpendicular to the attachment portion central longitudinal axis. This enables the dental component to be connected to the apically located dental implant component in a rotationally fixed manner. Many such indexing sections are known in the art and any can be used here. In particular, when the attachment portion comprises a post portion for insertion into the bore of a dental implant component, this post portion may comprise one or more laterally extending (e.g. radially) indexing protrusion (known as an “attachment indexing protrusion” herein). See, for instance, FIGs. 5, 5A and 5B. Such indexing protrusion(s) is configured to prevent axial rotation (around the attachment portion central longitudinal axis) of the dental component relative to the dental implant component when the dental implant component is engaged with the one or more indexing protrusion. Such indexing protrusion(s) is further configured for longitudinal slidable engagement with a complementary receiving opening in the dental implant component.

Additionally or alternatively, as mentioned above, the dental component may be provided with an open channel extending from the apical end to the prosthetic connection portion of the component.

The open channel may be configured to receive a threaded fastener. The open channel may be configured for tightening of the dental component, using the threaded fastener, to the dental implant component. The open channel may contain a stop member configured for engaging with a head of the threaded fastener.

Preferably the open channel extends along the attachment portion central longitudinal axis. When this axis is coaxial with the prosthetic connection portion central longitudinal axis, the open channel extends from the apical end to the coronal end of the dental component.

Alternatively, the open channel may be angled or curved and may extend from the apical end of the dental component to an opening on the lateral outer surface of the prosthetic connection portion of the dental component. Many suitable channels are known in the art and any can be used here.

Retention is an indication of pulling force (e.g. in Newtons (N)) required to pull apart a dental component and a prosthetic component that have been joined or connected together using cement. To measure retention of a dental component, a pull-out test may be used in which a vertical pulling force is applied to the dental component, while the dental prosthetic analogue is anchored, or vice versa. The pull-out force measured is the maximum pulling force applied before the connection between the components fails and the pieces separate.

The dental component may be made from any suitable biologically compatible metal, such as titanium or titanium alloy, or ceramic, e.g. zirconia. The dental component is preferably formed in one piece from such a material.

According to a further aspect of the present invention there is provided a method of providing one or more roughened area to a lateral outer surface of a prosthetic connection portion of a dental component, the method comprising the step of laser marking a regular pattern of microstructures over the entire surface of one or more area of the lateral outer surface in order to form the one or more roughened area.

The regular pattern of microstructures can have any of the preferred characteristics described above.

In certain preferred embodiments the method comprises the step of laser marking a plurality of regularly spaced macrogrooves over said one or more roughened area of the lateral outer surface prior to the step of laser marking the regular pattern of microstructures.

The plurality of regularly spaced macrogrooves can have any of the preferred characteristics described above. In particular, the plurality of regularly spaced macrogrooves may be arranged in a lattice structure.

Certain preferred embodiments of the present invention shall now be described, with reference to the accompanying drawings that form a part hereof, and in which are shown by way of illustration only specific embodiments in which the invention may be practiced. Parenthesized or emboldened reference numerals affixed to respective elements merely exemplify the elements by way of example, with which it is not intended to limit the respective elements. Unless otherwise indicated, all figures and drawings in this document are not to scale and are chosen for the purpose of illustrating different embodiments of the invention. In particular, the dimensions of the various components are depicted in illustrative terms only, and no relationship between the dimensions of the various components should be inferred from the drawings, unless so indicated.

It is to be understood that other embodiments may be utilised and structural or logical changes may be made without departing from the scope of the present invention. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims.

Figure Legends

FIG. 1 lateral cross-sectional view of a dental abutment connected to a prosthetic component, and a dental implant, wherein an apical attachment portion comprises a post.

FIG. 1A lateral cross-sectional view of a dental coping connected to a prosthetic component, and a dental abutment, wherein an apical attachment portion comprises a cavity.

FIG. 2 a three-dimensional view of a basic dental component as described herein, wherein the apical attachment portion comprises a post.

FIG. 2A a three-dimensional view of an alternative basic dental component as described herein, wherein the apical attachment portion comprises a post.

FIG. 2B a three-dimensional view of the basic dental component of FIG. 2, wherein the apical attachment portion comprises a cavity.

FIG. 2C a three-dimensional view of the basic dental component of FIG. 2A, wherein the apical attachment portion comprises a cavity.

FIG. 3 a three-dimensional view of the dental component of FIG. 2 disposed with a coronally facing annular surface.

FIG. 3A a three-dimensional view of the dental component of FIG. 2A disposed with a coronally facing annular surface.

FIG. 4 a three-dimensional view of the dental component of FIG. 2 disposed with prosthetic indexing protrusions.

FIG. 4A a transverse cross-section across plane 4a in FIG. 4.

FIG. 4B a three-dimensional view of the dental component of FIG. 2A disposed with prosthetic indexing protrusions.

FIG. 5 a three-dimensional view of the dental component of FIG. 2 disposed with attachment indexing protrusions.

FIG. 5A a transverse cross-section across plane 5a in FIG. 5. FIG. 5B a three-dimensional view of the dental component of FIG. 2A disposed with attachment indexing protrusions.

FIG. 6 a three-dimensional view of the dental component of FIG. 2 disposed with a transverse macrogroove.

FIG. 6A a three-dimensional view of an alternative dental component of FIG. 2 disposed with two transverse macrogrooves.

FIG. 7 is a three-dimensional representation of an exemplary dental abutment.

FIG. 8 Photographs of dental components having different treatments. Panel A: a dental component having roughened area(s) provided with a regular pattern of microstructures; Panel B: a dental component having roughened area(s) provided with an alternative regular pattern of microstructures; panel C: a dental component treated with grid structure of macrogrooves only; panel D: a dental component treated with a plurality of circumferentially extending macrogrooves only.

FIG. 9 Photographs of dental components having different treatments. Panel A: untreated dental component; Panel B: a dental component treated with roughened areas only; Panel C: untreated dental component; Panel D: a dental component treated with roughened areas only. FIG. 10 Photographs of dental component having different treatments. Panel A: sandblasted dental component; Panel B: a dental component treated with roughened area(s) only; Panel C: a dental component treated with roughened area(s) only.

FIG. 11 Scanning electron microscope images of a roughened area of a dental component at different magnifications (Panel A 100 pm scale; Panel B 20 pm scale).

FIG. 12 Scanning electron microscope image of a roughened area of a dental component comprising a plurality of regularly spaced macrogrooves.

Detailed description of invention

Exemplary dental components

Shown in FIGs. 1 to 7 is a dental component (100) having a coronal direction (10) and coronal end (10’) and an opposing apical direction (12) and apical end (12’), a medial (14) direction or part (towards a central longitudinal axis (A-A’) see FIGs. 1 and 1A) and a lateral (16) direction or part (away from a central longitudinal axis (A-A’) see FIGs. 1 and 1A).

In FIGs. 1 to 7, the dental component (100) has an apical end (12’) and a coronal end (10’).

The dental component comprises a prosthetic connection portion (102) extending from the coronal end (10’) in the apical direction (12) along a prosthetic connection portion central longitudinal axis (A-A’) for connection to a prosthetic component (300) and an attachment portion (104) extending from the apical end (12’) in the coronal direction (10) along an attachment portion central longitudinal axis (A-A’) for connection to a dental implant component (200). While in FIGS. 1 to 7 the attachment portion central longitudinal axis is shown as being coaxial to the prosthetic connection portion central longitudinal axis, and thus is indicated by the same reference number, it is appreciated that these axes could also be angled relative to one another.

While in FIGs. 1 , 2, 2A, 3, 3A, 4, 4B, 5, 5B, 6, 6A and 7 the attachment portion (104) is shown comprising a post portion for insertion into the bore of a dental implant component, e.g. implant 202 (see FIG. 1), it is appreciated that the attachment portion (104) may alternatively comprise a cavity (103) for housing the coronal portion of a dental implant component, e.g. an implant or abutment 204 (see FIG. 1A). This possibility is also shown in FIGs. 2B and 2C.

The prosthetic connection portion (102) comprises a lateral outer surface (106), the lateral outer surface (106) comprising one or more roughened area (110; 110, a to d) provided with a regular pattern of microstructures, indicated with shading in FIGs. 2 to 7. Also shown is at least one unroughened area (114; 114, a to e) adjacent to a roughened area (110) in the prosthetic connection portion (102) comprising an area of lateral outer surface (106) without the regular pattern of microstructures, indicated without shading in FIGs. 2 to 7.

In FIG. 1 , the dental component (100) is shown as an abutment connected by its prosthetic connection portion (102), for instance by cement, to the dental prosthetic component (300), and connected by its attachment portion (104) that is a post portion, for instance by threaded fastener (not shown), to a dental implant component (200) that is an implant (202).

In FIG. 1A, the dental component (100) is shown as a coping connected by its prosthetic connection portion (102), for instance by cement, to the dental prosthetic component (300), and connected by its attachment portion (104) that is a cavity (103), for instance by cement, to a dental implant component (200) that is an abutment (204). The abutment (204) is connected at its apical portion, for instance by threaded fastener (not shown), to an implant (202).

The dental component of the present invention may be an abutment or coping of the type depicted in FIGs. 1 and 1A. Alternatively it may be an abutment having an attachment portion comprising a cavity (103) or a coping having an attachment portion comprising a post portion.

In FIGs. 2, 2A, 2B and 2C basic dental components (100) according to the present invention are depicted. The dental components of Fig. 2A and Fig. 2C differ from those of Fig. 2 or Fig. 2B respectively only in that a plurality of roughened areas (100a, 100b, 100c) are shown, these areas being flanked by or spatially separated from each other by transverse bands of unroughened area (114, a; 114, b; 114, c; 114, d). The dental components of Fig. 2 and Fig. 2A have an attachment portion (104) comprising a post portion for insertion into the bore of a dental implant component. The dental components of Fig. 2B and Fig. 2C have an attachment portion (104) comprising a cavity (103) for housing the coronal portion of a dental implant component.

In FIGs. 3 and 3A, dental components (100) identical to those of FIG. 2 and 2A respectively are shown, with the exception that the lateral outer surface (106) comprises a coronally facing annular surface (122). The coronally facing annular surface (122) defines the apical end of the prosthetic connection portion (102). This surface (122) is configured to contact the apical end of the prosthetic component, thus providing a stop surface and load bearing surface. The radially outermost region of the coronally facing annular surface (122), as well as in these embodiments the remaining regions of the surface, lies in a plane perpendicular to the prosthetic connection portion central longitudinal axis (A-A). The coronally facing annular surface (122) extends laterally beyond the remainder of the prosthetic connection portion (102). In other words, the coronally facing annular surface (122) has a greater radius than the remainder of the lateral outer surface (106) of the prosthetic connection portion (102).

The coronally facing annular surface (122) is located outside the one or more roughened area (110, 110a, 110b, 110c) of the lateral outer surface (106). In other words, the coronally facing annular surface (122) is located in an unroughened area (114, b; 114, d) of the lateral outer surface (106) of the prosthetic connection portion (102). In this way, the coronally facing annular surface (122) can have a machined, smooth surface in order to provide a good seal between the dental component (100) and the prosthetic component (300).

The coronally facing annular surface (122) is disposed on an annular shoulder (120) having, in addition to the coronal facing annular surface (122), an opposing apically facing annular surface (124). Transverse cross-sections of the annular shoulder (120) taken at different positions in the longitudinal direction of the dental component all have a uniform size and shape. The apically facing annular surface (124) may be configured to contact the coronal end of the dental implant component, thus providing a stop surface and load bearing surface.

In FIGs. 4 and 4B, dental components (100) identical to those of FIG. 2 and 2A respectively are shown, with the exception that the lateral outer surface (106) comprises three laterally extending prosthetic indexing protrusions (130, a; 130, b; 130,c; see also FIG. 4a). These indexing protrusions (130, a; 130, b; 130,c) are configured to prevent axial rotation around the prosthetic connection portion central longitudinal axis (A-A) of the prosthetic component (300) relative to the dental component (100) when the prosthetic component (300) is engaged with the indexing protrusions (130, a; 130, b; 130, c). The prosthetic indexing protrusions (130, a; 130, b; 130, c) are located outside the one or more roughened area (110; 110, a; 110, b; 110, c). In other words, the indexing protrusions (130, a, 130, b, 130, c) are located in an unroughened area (114, b; 114, c; 114, d) of the lateral outer surface (106) of the prosthetic connection portion (102).

By locating the prosthetic indexing protrusions (130, a; 130, b; 130,c) in an unroughened area, a precise fit with the prosthetic component (300) can be ensured, since no surface of the protrusions (130, a; 130, b; 130, c,) are removed or distorted to provide the regular pattern of microstructures or plurality of regularly spaced macrogrooves (see FIGS 11 and 12).

FIG. 4A shows a transverse cross-section across plane 4A in FIGs. 4 and 4B. In FIG. 5 and 5B, dental components (100) identical to those of FIG. 2 and 2A respectively are shown, with the exception that the attachment portion (104) is disposed with six laterally (e.g. radially) extending attachment indexing protrusions (140, a; 140, b; 140, c) (see also FIG. 5A showing also 140, d; 140, e; 140, f).

FIG. 5A shows a transverse cross-section across plane 5A in FIGs. 5 and 5B.

In FIG. 6, a dental component (100) identical to that of FIG. 2 is shown, with the exception that the lateral outer surface (106) comprises an annular transverse macrogroove (150, a) located in a plane perpendicular to the prosthetic connection portion central longitudinal axis (A-A’). The annular transverse macrogroove (150, a) divides the roughened area of FIG. 2 into two roughened areas (110, a; 110,b).

In FIG. 6A, a dental component (100) identical to that of FIG. 2A is shown, with the exception that the lateral outer surface (106) comprises two annular transverse macrogrooves (150, a; 150, b) located in planes perpendicular to the prosthetic connection portion central longitudinal axis (A-A’) and located at discrete axial locations.

The transverse macrogrooves (150, a, 150, b) form axial height indicators and assist the user in shortening the dental component (100) to a desired height when required.

The transverse macrogrooves (150, a; 150, b) are located outside the roughened areas (110, a; 110,b; 110,c). In other words, the transverse macrogrooves (150, a; 150,b) are located in an unroughened area (114,b; 114,c) of the lateral outer surface (106) of the prosthetic connection portion (102). This improves the visibility of these grooves (150, a; 150, b) to the user.

In alternative embodiments, transverse bands of unroughened area (114, a; 114, b; 114, c; 114,d), of the type shown in Fig. 2A, may act as height indicators.

FIG. 7 is a three-dimensional representation of an exemplary dental abutment (180). The lateral outer surface (106) of the prosthetic connection portion (102) comprises a coronally facing annular surface (122), said coronally facing annular surface (122) defining the apical end of the prosthetic connection portion (102). The lateral outer surface (106) further comprises a circular cylindrical surface (108) located coronally of the coronally facing annular surface (122). The lateral outer surface (106) further comprises, coronal of the coronally facing annular surface (122), three radially extending prosthetic indexing protrusions (130, d, 130,e, 3^rd not shown) which extend radially from the circular cylindrical surface (108). Coronal of these protrusions (130,d, 130,e, 3^rd not shown), the lateral outer surface further comprises three annular transverse macrogrooves (150, a; 150, b; 150,c). The coronally facing annular surface (122), the prosthetic indexing protrusions (130, d; 130,e; 3^rd not shown) and the annular transverse macrogrooves (150, a; 150, b; 150,c) are located outside of the roughened areas (110, a to d), whereas the plurality of roughened areas (110, a to d) extend in aggregate over substantially the whole of the circular cylindrical surface (108) such that the whole circular cylindrical surface (108) is provided with a regular pattern of microstructures. In particular, one roughened area (110, a) extends to the coronal end (10’) of the lateral outer surface (106) of the prosthetic connection portion (102) while another roughened area (110,d) extends to within 2mm, e.g. to 0.8mm of the apical end, namely the coronally facing annular surface (122), of the lateral outer surface (106) of the prosthetic connection portion (102).

Unroughened areas (114, a to f) of the lateral outer surface (106) of the prosthetic connection portion (102) are further indicated as the coronally facing annular surface (122 - 114,f), the prosthetic indexing protrusions (130d - 114,d; 130e - 114,e) and the annular transverse macrogrooves (150, a - 114, a; 150, b - 114, b; 150, c - 114, c), and are devoid of the regular pattern of microstructures.

The coronally facing annular surface (122) is disposed on an annular shoulder (120). Transverse cross-sections of the annular shoulder (120) taken at different positions in the longitudinal direction of the dental abutment (180) have a gradually smaller footprint in the apical direction (12). Such a tapering annular shoulder (120) is beneficial when the dental abutment (180) is arranged to contact the soft tissue, as the tapering shoulder (120) can assist in forming a natural emergence profile through the soft tissue.

The attachment portion (104) comprises a post portion for insertion into the bore of a dental implant, the attachment portion (104) being located entirely apical of the prosthetic connection portion (102). The attachment portion (104) comprises an indexing section (142) having a non-circular-symmetric cross-section in a plane perpendicular to the attachment portion central longitudinal axis, which in this embodiment is coaxial to the prosthetic connection portion central longitudinal axis (A-A’). In the present case, the indexing section (142) comprises six laterally (e.g. radially) extending attachment indexing protrusions (140, g to I).

An open channel (160) extends between the apical end (12’) and coronal end (10’) of the abutment (180).

The roughened areas (110, a to d) of the lateral outer surface (106) of the prosthetic connection portion (102) are provided with a regular pattern of microstructures.

In the present embodiments this pattern consists of an array of microstructures (170), the microstructures being arranged in a series of offset rows, each row being located in a plane perpendicular to the prosthetic connection portion central longitudinal axis (A-A). The size of the microstructures is such that they are not discernable with the naked eye, however for better understanding the array is shown in enlarged form in Fig. 11, panels A and B.

The roughened areas (110, a to d) may be provided solely with a regular pattern of microstructures, for example of the type shown in FIG. 11. Alternatively, the roughened areas (110, a to d) may further comprise a plurality of regularly spaced macrogrooves (175, a; 175, b) for increasing the roughness of the roughened areas. An example of such a roughened area is shown in FIG. 12.

FIG. 12 shows a plurality of regularly spaced macrogrooves (175, a to d;) arranged in a lattice structure, one set of the regularly spaced macrogrooves (175, a; 175,c) being aligned in parallel in one direction, and a second set of the regularly spaced macrogrooves (175, b; 175, d) being aligned in parallel in another direction, each macrogroove of the plurality of macrogrooves extending at an oblique angle to the prosthetic connection portion central longitudinal axis (A-A’). In addition, a regular pattern of microstructures (170) covers the entire surface of the roughened area, inclusive of the plurality of macrogrooves (175, a to d). The regular pattern of microstructures comprises a plurality of repeated circumferential paths (172, a; 172, b), each path being formed by a plurality of discrete microstructures (170).

Experimental examples

A plurality of dental components were used in pull-out tests to determine the force required to pull a dental component from a dental prosthetic analogue that had been cemented in place.

Different roughened area(s) were applied to the lateral outer surface of the prosthetic connection portion of the test dental components using laser marking. The lateral outer surface of control dental components were left untreated, or only sandblasted.

The internal geometry of the prosthetic analogue corresponds to the same internal geometry of a regular prosthetic component. The cement gap was chosen to the regular value of 0.03mm. These prosthetic analogs were each produced using the same material (Katana Zirconia YML). After the analogs were milled from blanks, they were oven baked. Subsequently, the internal connection was manually sandblasted, cleaned and a primer applied (Panavia Ceramic Primer Plus). A cement (Panavia V5 Opaque) was applied to each prosthetic analogue and these were pressed with a controlled force to the dental components to be tested. A drying time at room temperature of 24 hours was observed.

To measure retention of each dental component, the pull-out test was applied in which a vertical pulling force was applied to the prosthetic analogue, while the dental component was anchored to an implant analog. The pull-out force measured is the maximum pulling force applied before failure of the cemented joint. The results are shown in Tables 1 to 4.

Table 1 5 samples of each version, which were identical apart from the roughened areas applied, were prepared and measured.

The results of Table 1 show a larger retention force between a prosthetic connection portion having roughened areas provided with a regular pattern of microstructures (Version 1 and 2) as described herein, compared with a prosthetic connection portion having a laser marking formed of macrogrooves only (no roughened areas in accordance with the present invention) (Version 3 and 4).

Table 2. 30 samples of each version were prepared and measured. Versions 5 and 6: identical apart from the application of a roughened area on Version 6; versions 7 and 8: identical apart from the application of a roughened area on Version 8.

The results of Tab e 2 show a large retention force between a prosthetic connection portion having roughened areas (Version 6 and 8) as described herein, compared with a prosthetic connection portion that is untreated (no roughened areas) (Version 5 and 7).

Table 3. Samples of each version were prepared and measured. The samples were identical apart from the roughened areas applied.

The results of Tab e 3 show a large retention force between a prosthetic connection portion having roughened areas (Version 10 and 11) as described herein, that is improved over a prosthetic connection portion that is sandblasted (no roughened areas) (Version 9).

Table 4. Samples were prepared having 5 alternative roughened area(s) provided with a regular pattern of microstructures. Control samples were prepared having an untreated and sandblasted surface. (Ra) and (Rz) values were measured according to ISO 21290.

The results of Table 4 show a large retention force between a prosthetic connection portion having roughened areas (Versions 13 to 17) as described herein, that is improved over a prosthetic connection portion that is sandblasted (no roughened areas) (Version 12) or untreated (Version 18).

Certain embodiments of the invention

Provided herein is a dental component (100) comprising:

- an apical end (12’);

- a coronal end (10’);

- an attachment portion (104) extending from the apical end in a coronal direction along an attachment portion central longitudinal axis, the attachment portion being configured for connection to a dental implant component (200); and

- a prosthetic connection portion (102) extending from the coronal end in an apical direction along a prosthetic connection portion central longitudinal axis (A-A’), the prosthetic connection portion being configured for connection to a prosthetic component (300), the prosthetic connection portion comprising a lateral outer surface (106); wherein the lateral outer surface (106) comprises one or more roughened area (110) each provided with a regular pattern of microstructures (170), the regular pattern of microstructures covering the entire surface of the one or more roughened area (110).

According to a preferred aspect, the regular pattern of microstructures (170) each has an arithmetical mean height (Sa) in a range of 0.5 to 2 microns, more preferably 0.6 to 1.8 microns. According to a preferred aspect, the regular pattern of microstructures (170) each has a surface topography defined by an arithmetical mean height (Sa) of between 0.5 and 2 microns, more preferably 0.6 and 1 .8 microns, a maximum height (Sz) of between 2.5 and 11 microns and a skewness (Ssk) of between -0.4 and 0.5.

According to a preferred aspect, the regular pattern of microstructures (170) each has a surface topography defined by a skewness (Ssk) of greater than or equal to zero and a maximum height (Sz) of between 2.5 and 7 microns.

According to a preferred aspect, the regular pattern of microstructures (170) each has a surface topography defined by a skewness (Ssk) of greater than zero and a maximum height (Sz) of between 2.5 and 7 microns.

According to a preferred aspect, the regular pattern of microstructures (170) each has a surface topography defined by an arithmetical mean deviation of the assessed profile (Ra) of between 0.5 and 2 microns and a maximum height of the profile (Rz) of between 1 and 12 microns.

According to a preferred aspect, adjacent microstructures (170) within each regular pattern are positioned within 75 microns, preferably within 50 microns of each other.

According to a preferred aspect, the distance between adjacent microstructures (170) within each regular pattern is less than the width of the microstructures themselves.

According to a preferred aspect, each regular pattern of microstructures (170) comprises a plurality of repeated helical paths, a plurality of repeated closed circumferential paths, a plurality of repeated open circumferential paths, a plurality of repeated longitudinal paths, or a combination of two or more of these.

According to a preferred aspect, each regular pattern of microstructures (170) comprises an array of discrete microstructures, the microstructures being arranged in a series of rows, each row being located in a plane perpendicular to the prosthetic connection portion central longitudinal axis. According to a preferred aspect, the one or more roughened area (110) further comprises a plurality of regularly spaced macrogrooves (175, a; 175,b), the regular pattern of microstructures (170) covering the entire surface of the one or more roughened area inclusive of the plurality of macrogrooves.

According to a preferred aspect, in aggregate the one or more roughened area covers at least 50% of the lateral outer surface (106) of the prosthetic connection portion (102), more preferably at least 75% of the lateral outer surface of the prosthetic connection portion

According to a preferred aspect, the lateral outer surface (106) of the prosthetic connection portion (102) comprises one or more laterally extending indexing protrusion (130, a; 130, b; 130, d; 130,e) configured to prevent rotation around the prosthetic connection portion central longitudinal axis (A-A’) of the prosthetic component (300) relative to the dental component (100), the one or more indexing protrusion being located outside the one or more roughened area (110).

According to a preferred aspect, the lateral outer surface (106) of the prosthetic connection portion (102) comprises one or more transverse macrogroove (150, a; 150, b; 150, c), said one or more macrogroove being located in a plane perpendicular to the prosthetic connection portion central longitudinal axis (A-A’) and being located outside the one or more roughened area (110).

According to a preferred aspect, the lateral outer surface (106) of the prosthetic connection portion (102) comprises a coronally facing annular surface (122), said coronally facing annular surface defining the apical end of the prosthetic connection portion and being located outside the one or more roughened area (110).

According to a preferred aspect, the dental component is a dental abutment or is a dental coping.

According to a preferred aspect, the regular pattern of microstructures is formed by laser marking. According to a preferred aspect, is a method of providing one or more roughened area (110) to a lateral outer surface (106) of a prosthetic connection portion (102) of a dental component (100), the method comprising the step of: laser marking a regular pattern of microstructures (170) over the entire surface of one or more area of the lateral outer surface in order to form the one or more roughened area.

Claims

1 . A dental component (100) comprising:

- an apical end (12’);

- a coronal end (10’);

2. The dental component (100) as claimed in claim 1 , wherein the regular pattern of microstructures (170) each has an arithmetical mean height (Sa) in a range of 0.5 to 2 microns, more preferably 0.6 to 1 .8 microns.

3. The dental component (100) as claimed in claim 2, wherein the regular pattern of microstructures (170) each has a surface topography defined by an arithmetical mean height (Sa) of between 0.5 and 2 microns, more preferably 0.6 and 1.8 microns, a maximum height (Sz) of between 2.5 and 11 microns and a skewness (Ssk) of between -0.4 and 0.5.

4. The dental component (100) as claimed in claim 1 , wherein the regular pattern of microstructures (170) each has a surface topography defined by a skewness (Ssk) of greater than zero and a maximum height (Sz) of between 2.5 and 7 microns.

5. The dental component (100) as claimed in any preceding claim, wherein the regular pattern of microstructures (170) each has a surface topography defined by an arithmetical mean deviation of the assessed profile (Ra) of between 0.5 and 2 microns and a maximum height of the profile (Rz) of between 1 and 12 microns.

6. The dental component (100) as claimed in any preceding claim, wherein adjacent microstructures (170) within each regular pattern are positioned within 75 microns, preferably within 50 microns of each other.

7. The dental component (100) as claimed in any preceding claim, wherein the distance between adjacent microstructures (170) within each regular pattern is less than the width of the microstructures themselves.

8. The dental component (100) as claimed in any preceding claim, wherein each regular pattern of microstructures (170) comprises a plurality of repeated helical paths, a plurality of repeated closed circumferential paths, a plurality of repeated open circumferential paths, a plurality of repeated longitudinal paths, or a combination of two or more of these.

9. The dental component (100) as claimed in any preceding claim, wherein each regular pattern of microstructures (170) comprises an array of discrete microstructures, the microstructures being arranged in a series of rows, each row being located in a plane perpendicular to the prosthetic connection portion central longitudinal axis.

10. The dental component (100) as claimed in any preceding claim, wherein the one or more roughened area (110) further comprises a plurality of regularly spaced macrogrooves (175, a; 175, b), the regular pattern of microstructures (170) covering the entire surface of the one or more roughened area inclusive of the plurality of macrogrooves.

11 . The dental component (100) as claimed in any preceding claim, wherein in aggregate the one or more roughened area covers at least 50% of the lateral outer surface (106) of the prosthetic connection portion (102), more preferably at least 75% of the lateral outer surface of the prosthetic connection portion

12. The dental component (100) as claimed in any preceding claim, wherein the lateral outer surface (106) of the prosthetic connection portion (102) comprises one or more laterally extending indexing protrusion (130, a; 130, b; 130, d; 130, e) configured to prevent rotation around the prosthetic connection portion central longitudinal axis (A-A’) of the prosthetic component (300) relative to the dental component (100), the one or more indexing protrusion being located outside the one or more roughened area (110).

13. The dental component (100) as claimed in any preceding claim, wherein the lateral outer surface (106) of the prosthetic connection portion (102) comprises one or more transverse macrogroove (150, a; 150, b; 150,c), said one or more macrogroove being located in a plane perpendicular to the prosthetic connection portion central longitudinal axis (A-A’) and being located outside the one or more roughened area (110).

14. The dental component (100) as claimed in any preceding claim, wherein the lateral outer surface (106) of the prosthetic connection portion (102) comprises a coronally facing annular surface (122), said coronally facing annular surface defining the apical end of the prosthetic connection portion and being located outside the one or more roughened area (110).

15. The dental component (100) as claimed in any preceding claim, wherein the dental component is a dental abutment or is a dental coping.

16. The dental component (100) as claimed in any preceding claim, wherein the regular pattern of microstructures is formed by laser marking.

17. A method of providing one or more roughened area (110) to a lateral outer surface (106) of a prosthetic connection portion (102) of a dental component (100), the method comprising the step of: laser marking a regular pattern of microstructures (170) over the entire surface of one or more area of the lateral outer surface in order to form the one or more roughened area.