Denture base and dental prosthesis

Abstract

To provide a denture base having a plurality of tooth socket compartments where one or more of the tooth socket compartments comprises a convex surface configured in step-like structure, and one or more prominences on the step-like structure.SOLUTION: The present invention further relates to a dental prosthesis including the denture base, at least one bonding agent, and a plurality of artificial teeth. Each artificial tooth is bonded within a tooth socket compartment such that the artificial tooth can rest upon the top of each prominence 215a, 225a in the tooth socket compartment, maintaining a predetermined amount of bonding agent between the artificial tooth and the denture base. The denture base and dental prosthesis of the invention can better address the need for easier, more efficient and reliable set-up of artificial teeth in a denture base, and ensuring more consistent and predictable bonding of artificial teeth in a denture base.SELECTED DRAWING: Figure 6A

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This patent application claims the benefit of and priority to U.S. Application No. 16 / 277,342, filed February 15, 2019, which is incorporated herein by reference for all purposes. [Background technology]

[0002] In the field of dental prosthetics, the arrangement of teeth in a denture base is a critical task. It requires a skilled technician with thorough knowledge of the entire denture fabrication process, i.e., tooth design (width and length), bite angle, and overall tooth arrangement scheme. Even for a skilled technician, accurate placement and fitting of artificial teeth in a denture base often requires repeated interventions. For example, slight dimensional variations or defects formed in the basal surface area of ​​prefabricated teeth and the inner surface of the alveolar cavity of the receiving denture base can contribute to instability (e.g., rocking or rotation) or malalignment (e.g., tilt or imbalance) of the tooth arrangement in the denture base. Considerable time and effort may be spent in the process of carefully adjusting and correcting existing dimensional deviations or incongruities (in either the artificial teeth or the denture base) to achieve both proper function and esthetics of the denture for the patient. Thus, accurate tooth arrangement remains a more difficult and therefore more time-consuming and expensive process than desired.

[0003] One of the important advantages of cast-molded teeth is their aesthetics. In many cases, the external surface shades and features of these teeth make them appear realistic and therefore difficult to distinguish from natural teeth. The overall cast-molding process results in generally good dimensional consistency with a wide variety of designs. However, despite efforts to minimize or eliminate the formation of undesirable variations in the tooth surfaces, it is not uncommon for the cast-molding process to introduce small surface anomalies or defects (e.g., bulges or ridges at seam lines or sprue areas of the mold) into at least one tooth surface. Typically, to avoid a detrimental appearance to the visible tooth surfaces, manufacturers design tooth molds to isolate such defects to the base or inferior portion of the molded tooth that will be placed and attached to the denture base. However, to isolate these surface defects to the non-visible underlying tooth surfaces, such surface anomalies or variations are then subject to interference with the alveolar and protrusive contact of the denture base, thus becoming a causative factor in the above-mentioned instability and malalignment of the tooth placement in the denture base. Thus, to improve the fit or otherwise overcome these problems, technicians must use considerable experience and judgment, exercise caution, and laboriously remove some surface area of ​​the teeth by grinding or polishing. They may even have to repeat such efforts across multiple teeth required to complete the denture for a satisfactory result, thus adding more time and expense to completion.

[0004] With recent improvements in CAD / CAM design and fabrication techniques utilizing CNC milling or additive manufacturing (i.e., 3D printing), denture bases and teeth can be fabricated with favorable accuracy and efficiency compared to more traditional cast molding techniques. By designing denture bases and teeth in a digital environment, a virtual library of various artificial tooth shapes can be applied to provide complementary or matching modifications to the denture base surfaces to receive preformed artificial teeth. However, additional difficulties or shortcomings may be encountered in creating precisely matching surfaces between the teeth and denture base. First, during the insertion and positioning of these surfaces relative to one another, extensive inter-surface friction or adhesion due to such a close-fitting arrangement can create an undesirable interference or "tight bond" effect. This can prevent the technician from making subtle but important positional changes to optimize the orientation and alignment of the teeth within the denture base. In such cases, the technician may be forced to make small subtractive adjustments (e.g., removing surface area of ​​the artificial teeth and / or denture base) to create more room between the surfaces. In this way, well-intentioned interventions to improve fit may inadvertently result in undesirable physical imbalances / distortions or visible defects, necessitating yet further time-consuming corrective actions. Second, during the process of permanently fixing each artificial tooth to the denture base, one or more hardening adhesives or bonding materials are typically placed between the basal surface of the artificial tooth and the alveolus of the denture base to fix them to each other. If the mating areas of the basal surface of the artificial tooth and the alveolus of the denture base are precisely matched and brought into contact with each other over their entire surfaces, the integrity of the bonding process and the bonding quality may be compromised. That is, the bonding quality may be more variable (less consistent) across both different teeth within the same denture as well as different dentures. More specifically, when mating teeth and denture bases to each other, the bonding quality may be more strongly influenced by factors such as the amount and viscosity of the bonding material provided and the amount of pressure applied by the technician (i.e., creating a more inconsistent and unpredictable adhesive layer interface).

[0005] For the above reasons, there is a need, particularly for milled and additively manufactured denture bases, for denture bases and dentures that are less labor intensive to produce and can provide easier, more efficient and reliable arrangement of artificial teeth as well as more consistent adhesion of the artificial teeth. Summary of the Invention

[0006] The present invention relates to denture bases and dentures that meet these and other needs. A denture base having features of the invention includes a dental arch form and a plurality of alveolar compartments formed concavely within the dental arch form. One or more of the alveolar compartments include a convex surface having a stepped structure characterized by a tread-like lingual base surface and a riser-like buccal base surface. The stepped structure may project or extend outwardly from the lingual-facing side of the alveolar compartment to the buccal-facing side of the alveolar compartment and substantially across the width of the alveolar compartment in a mesial to distal direction. One or more projections may project from a location on the stepped structure, the location being: a) The stepped lingual base surface, b) Step-like structure of the buccal base; c) the lingual base of the stepped structure and the buccal base of the stepped structure; d) both the lingual and buccal base surfaces having a stepped configuration with projections extending in a continuous fashion across at least a portion of both the lingual and buccal base surfaces; and e) A combination of these is selected from the group consisting of:

[0007] In one embodiment of the invention, the lingual base surface of the stepped structure of the alveolar compartment may be substantially flat over the entire length of that region, excluding any protrusions protruding from the lingual base surface.

[0008] In another embodiment of the invention, the buccal base surface of the stepped structure of the alveolar compartment may be substantially convex across its width and substantially flat along its riser height, excluding any protrusions projecting from the buccal base surface.

[0009] In yet another embodiment of the invention, the buccal base surface of the stepped structure of the alveolar compartment may be substantially convex across its width and substantially convex along its riser height, excluding any protrusions projecting from the buccal base surface.

[0010] In one embodiment, the protrusions may be at least about 25 microns in height and no greater than about 500 microns in height.

[0011] In yet another embodiment, the protrusions may be at least about 25 microns wide at their widest point and no wider than about 10 millimeters wide at their widest point.

[0012] In a further embodiment of the invention, the at least two projections may protrude from a lingual basal surface of the stepped structure of the alveolar compartment.Similarly, in another embodiment of the invention, the at least two projections may protrude from a buccal basal surface of the stepped structure of the alveolar compartment.

[0013] In embodiments in which at least two protrusions protrude from the lingual base surface of the stepped structure, each of the protrusions on the lingual base surface may be of essentially equal height to one another.Similarly, in embodiments in which at least two protrusions protrude from the buccal base surface of the stepped structure, each of the protrusions on the buccal base surface may be of essentially equal height to one another.

[0014] In other embodiments in which at least two projections protrude from the lingual base surface of the stepped structure, the projections on the lingual base surface may be located substantially equidistant from the bisection plane of the alveolar compartment, where the bisection plane of the alveolar compartment is essentially perpendicular from the mesial to the distal direction of the alveolar compartment. Similarly, in embodiments in which at least two projections protrude from the buccal base surface of the stepped structure, the projections on the buccal base surface may be located substantially equidistant from the bisection plane of the alveolar compartment, where the bisection plane of the alveolar compartment is essentially perpendicular from the mesial to the distal direction of the alveolar compartment.

[0015] In yet other embodiments in which at least two protrusions protrude from the lingual and / or buccal base surfaces of the stepped structure, the protrusions may be separated by a distance of at least about 25 microns and no more than about 8 millimeters when measured from the periphery at the base of the protrusions.

[0016] The denture may include a denture base embodying one or more features of the present invention. The denture may further include at least one bonding material and a plurality of artificial teeth bonded to the denture base. The size and shape of the base surface of each artificial tooth is configured to be received in at least one of the alveolar compartments of the denture base of the present invention. Each artificial tooth is bonded in the alveolar compartment by at least one bonding material such that the base surface of each artificial tooth is supported by a protrusion in the alveolar compartment such that a predetermined amount of bonding material is maintained between the artificial teeth and the denture base.

[0017] These and other features, aspects, exemplary embodiments and advantages of the present invention will become better understood with regard to the following description, appended claims and accompanying drawings. [Brief description of the drawings]

[0018] [Figure 1] 1 shows a perspective view of a digital image of an upper (maxillary) complete denture base embodying certain aspects of the present invention. [Diagram 2] 2 shows an enlarged perspective view of a portion of the digital image of the denture base of FIG. 1; [Diagram 3] FIG. 2 shows a partially enlarged side view of a digital image of an alveolar compartment and a stepped anatomical protrusion within a portion of a dental arch form. [Figure 4A] FIG. 2 shows a side view of a single alveolar compartment including one embodiment of a transition surface area where a substantially flat lingual base surface meets the periphery of the alveolar compartment. [Figure 4B] A cross-sectional view (i.e., a view perpendicular to the curvature of the dental arch form, i.e., from mesial to distal) is shown showing the stepped structures and protrusions in the alveolar compartment. [Figure 4C]A top view of a single alveolar compartment (i.e., looking down on the dental arch form oriented in an upwardly facing direction with the alveolar compartment) is shown including different embodiments of the transition surface area where the convex buccal base surface meets the periphery of the alveolar compartment. [Figure 4D] A top view of a single alveolar compartment (i.e., looking down on the dental arch form oriented in an upwardly facing direction with the alveolar compartment) is shown including different embodiments of the transition surface area where the convex buccal base surface meets the periphery of the alveolar compartment. [Diagram 5] 5A-5H show several representative forms of cross-sectional profile shapes or protrusion contours. [Figure 6A] A cross-sectional view of an artificial tooth is shown with its base surface supported or positioned on protrusions of essentially equal, i.e. matching, height on the lingual and buccal base surfaces of a stepped structure in the alveolar compartment. [Figure 6B] A cross-sectional view of an artificial tooth with its base surface supported or positioned on protrusions of unequal or mismatched heights on the lingual and buccal base surfaces of a stepped structure in the alveolar compartment is shown. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] In the summary above and in the detailed description and claims provided below in conjunction with the accompanying drawings, reference is made to specific features and embodiments of the invention. It is to be understood that the disclosure of the invention herein includes all possible combinations of such specific features. For example, if a specific feature is disclosed in the context of a specific aspect or embodiment of the invention or a specific claim, that feature, to the extent possible, can also be used in combination with and / or in the context of other specific aspects and embodiments of the invention, and in the invention broadly.

[0020] The following additional definitions shall apply throughout the present specification and claims, unless specifically indicated otherwise.

[0021] The term "about" is used herein as an approximation to mean ±5% of the specified value, preferably ±3% of the specified value, and more preferably ±1% of the specified value.

[0022] The terms "essentially" and "substantially" are used herein as approximation terms to mean in most cases, but not necessarily in whole or complete, in relation to the essential property or dominant characteristic being described.

[0023] The term "at least" before a number is used herein to denote the beginning of a range beginning with that number (which may or may not have an upper limit, depending on the variable being defined). For example, "at least one" means one or more than one.

[0024] The terms "up to" or "less than" before a number are used herein to mean the end of a range ending with that number (which may be a range with 1 or 0 as its lower limit or a range with no lower limit, depending on the variable being defined). For example, "up to 100" or "less than 100" means 100 or less than 100. When a range is given herein as "from (first number) to (second number)" or "from (first number) to (second number)", this means a range whose lower limit is the first number and whose upper limit is the second number. For example, 1 to 5 mm means a range whose lower limit is 1 mm and whose upper limit is 5 mm.

[0025] As used herein, the term "and / or" includes any and all possible combinations of one or more of the associated listed items, as well as the absence of a combination when interpreted as an alternative ("or"). For example, "A and / or B" means A only, B only, or both A and B, or a mixture thereof.

[0026] Directional or spatially relative terms such as "under," "below," "beneath," "lower," "over," "upper," "above," "on top," and the like may be used herein for ease of description to describe the relationship of an element or feature shown in a figure to other elements or features. Of course, spatially relative terms are intended to encompass different orientations of the device in addition to the orientation depicted in the figures. For example, if the device in the figures is inverted, an element or feature described as "above" or "on top" of another element or feature would be oriented "below" or "under" the other element or feature. The device may be otherwise oriented (e.g., rotated 90 degrees or otherwise) and the spatially relative descriptors used herein interpreted accordingly. Similarly, terms such as "upper," "lower," "vertical," and "horizontal" are used herein for relative description purposes only, unless specifically indicated otherwise.

[0027] The term "dental arch form" is used herein to mean the three-dimensional curved configuration or shape of a dental arch, either the upper (maxillary) arch or the lower (mandibular) arch, that resembles the contour in which the alveolar crest and dentition lie. It should also be understood that "dental arch form" is not limited to only complete denture bases and dentures, but is intended to apply to partial denture bases and dentures as well.

[0028] The term "stepped" is used herein to mean a configuration or shape that resembles or has the appearance of a step-shaped profile.

[0029] The term "tread-like" is used herein to mean a substantially horizontal upper portion or surface of a "stepped" structure that resembles or has the appearance of a horizontal tread portion of a staircase.

[0030] The term "rise-like" is used herein to mean a substantially vertical upright or surface of a "step-like" structure that resembles or appears to be a vertical riser between the separate tread surfaces of a staircase.

[0031] The term "lingual-facing side" is used herein to mean the direction or space adjacent to or facing towards the tongue in the oral cavity.

[0032] The term "cheek-facing side" is used herein to mean the direction or space adjacent to or facing toward the cheeks and / or lips of the oral cavity.

[0033] The term "base" is used herein to mean a location relative to a foundation or located at, forming or belonging to the base or bottom region of an element or feature.

[0034] The term "lingual base" is used herein to mean a substantially horizontal portion in the alveolar compartment adjacent or proximate to the tongue-facing side of the denture base.

[0035] The term "buccal base" is used herein to mean a substantially vertical upstanding portion in the alveolar compartment adjacent or proximate to the cheek-facing side of the denture base.

[0036] The term "mesial-to-distal" is used herein to mean the direction of curvature of the dental arch from the centerline or midsagittal plane of the dental arch to the distal or distal end of the dental arch.

[0037] As shown in FIG. 1 for an upper (or maxillary) complete denture base, the denture base (100) includes a dental arch form (110) and a number of alveolar compartments (120) recessed into the dental arch form. The dental arch form may further be considered as having a tongue-facing side (the "LF side" shown in FIG. 1) and a cheek-facing side (the "BF side" shown in FIG. 1). As shown in FIG. 1, the alveolar compartments may advantageously be located adjacently with respect to the dental arch form along a mesial-distal direction (the MDO line shown in FIG. 1). It is also advantageous that each of the alveolar compartments is configured to receive a suitable artificial tooth form to ensure a more natural looking denture. Without intending to be limiting, a suitable artificial tooth form is one whose outer contour or shape profile and size correspond to the appropriate artificial tooth type (i.e., incisor, canine, premolar, molar) and / or tooth number (as used in the FDI World Dental Federation notation) associated with the natural oral anatomy and location along the dental arch. It should also be understood that while FIG. 1 is representative of the form of the present invention, the present invention is not limited to only upper (maxillary) complete denture bases. Also, embodiments of the present invention may be applied to upper partial denture bases, lower (mandibular) complete denture bases, and lower partial denture bases.

[0038] As shown in Figure 2, at least one of these alveolar compartments, and preferably a plurality of these alveolar compartments, may be defined by a convex surface configured in a stepped structure (200) characterized by a tread-like (substantially horizontal portion) lingual base surface (210) and a riser-like (substantially vertical portion) buccal base surface (220). The stepped structure projects or extends outwardly from the lingual-facing side ("LF side") of the alveolar compartment to the buccal-facing side ("BF side") of the alveolar compartment and substantially across the width of the alveolar compartment in a mesial to distal direction.

[0039] In Fig. 2, protrusions (215a, 215b) are shown projecting or extending outward from the tread-like lingual base surface (210). Protrusions are surface structures or surface features that project or extend outward from the surface of the step-like structure (200) in the alveolar compartment. Further protrusions (225a, 225b) are shown projecting or extending outward from the riser-like buccal base surface (220). Fig. 3 shows an enlarged side view of the alveolar compartment in a dental arch form. Again, protrusions (215a, 215b) are shown projecting or extending outward from the tread-like lingual base surface (210) and protrusions (225a, 225b) are shown projecting or extending outward from the riser-like buccal base surface (220).

[0040] Step-like structure In one embodiment of the invention, the stepped structure of the alveolar compartment may have a substantially flat tread-like lingual base surface throughout the entire length of that region in the alveolar compartment, excluding any protrusions that protrude from the lingual base surface. As used herein, "substantially flat" means that the region is generally or mostly flat, but not necessarily entirely or completely. For example, in the embodiment of the invention shown in Figures 4A and 4B, there may be a generally or mostly flat surface area extending throughout the central portion of the tread-like lingual base surface (210), which transitions into an arched or curved surface area (230) that meets the periphery of the alveolar compartment (120). Additionally or alternatively, in another form of the invention shown in FIG. 4B, there may be a generally or mostly flat surface area extending across the central portion of the tread-like lingual base surface, which transitions to an arched or curved surface area (235) where the distal free end extending outside the lingual base surface (210) meets the distal free end extending outside the buccal base surface (220) of the alveolar compartment.

[0041] In another embodiment of the invention, the stepped structure of the alveolar compartment may have a riser-like buccal base surface that is substantially convex across its width, excluding the projections that protrude from the buccal base surface, and substantially flat across its riser height. As used herein, "substantially convex" means that the area is generally or mostly convex, but not necessarily entirely or completely. For example, in one form of the invention shown in FIG. 4C, there may be a generally or mostly convex surface area that extends across the central portion of the riser-like buccal base surface (220) across its width, which transitions to a flat surface area (250) where the buccal base surface meets the periphery of the alveolar compartment (120). Alternatively, as shown in Figure 4D, there may be a generally or mostly convex surface area extending across the central portion of the riser-like buccal base surface (220) across its width, which transitions into an arcuate or curved surface area (250) where the buccal base surface meets the periphery of the alveolar compartment (120). In other embodiments of the invention, the stepped structure of the alveolar compartment may have a riser-like buccal base surface that is substantially convex across its width and substantially convex across its riser height, excluding any projections that project from the buccal base surface.

[0042] In one embodiment of the invention, the angle (α) shown in Figure 4B formed between the tread-like lingual base surface and the riser-like buccal base surface may be at least about 80° and not more than about 110°. In a more preferred embodiment, the angle formed between the tread-like lingual base surface and the riser-like buccal base surface may be at least about 85° and not more than about 100°.

[0043] protrusion In one embodiment of the invention, one or more protrusions may protrude or extend outwardly from only the lingual basal surface, while in another embodiment of the invention, one or more protrusions may protrude or extend outwardly from only the buccal basal surface.

[0044] In a preferred embodiment of the invention, one or more protrusions may protrude or extend outwardly from the lingual basal surface and one or more protrusions may protrude or extend outwardly from the buccal basal surface.

[0045] In yet another preferred embodiment, one or more projections may project or extend continuously or uninterrupted outwardly from both the lingual and buccal basal surfaces.

[0046] In one embodiment, the protrusions may be formed (e.g., by casting, subtractive (CNC milling) or additive manufacturing (3D printing) processes) as an integral, tightly integrated structure emanating from the surface of the stepped structure. Herein, the protrusions may be of the same material or composition as the surrounding alveolar compartment and arch form of the denture base. In another embodiment, the protrusions may be formed by a separate or independent process (such as by overmolding or 3D printing) so as to be adjacent and fixed or bonded firmly to the surface of the stepped structure. Herein, the protrusions may be of at least one material or composition different from the surrounding alveolar compartment and arch form of the denture base. The at least one different material or composition may be selected based on physical properties, for example, to be less hard or rigid (i.e., more flexible, compressible or elastic) relative to the material or composition of the surrounding alveolar compartment and arch form. Such materials or compositions may have a durometer hardness ranging from a value of about 10 on the Shore 00 durometer scale to a value of about 100 on the Shore D durometer scale.

[0047] The protrusions may be formed in a variety of shapes without being limited thereto. FIG. 5 shows some representative forms of the cross-sectional profile shape or contour of the protrusions. These are representative forms intended to illustrate some, but not all, of the possible contour embodiments of the present invention. In one embodiment, the top of the protrusion may be in the form of a dot or line (as illustrated in FIGS. 5A-5B). In another embodiment, the top of the protrusion may be in the form of a rounded or curved surface (as illustrated in FIGS. 5C-5E). In another preferred embodiment, the top of the protrusion may be in the form of a substantially flat surface or plane (as illustrated in FIGS. 5F-5H). In such an embodiment where the top of the protrusion is in the form of a substantially flat surface or plane, the planar surface area itself may be any shape. Without intending to be limiting, such shapes may be circular, oval, semicircular, semimoon, triangular, square, rectangular, diamond, symmetrical or asymmetrical (i.e., irregular) shapes.

[0048] For example, the height (hp) of a protrusion as shown in FIG. 5A is the distance between its apex (e.g., the top / outer surface that can contact the artificial tooth) and its origin extending outward from its lower base or stepped structure surface (210, 220). The height of the protrusion may be selected during the design and fabrication of the denture base to ensure that an effective, predetermined gap spacing or separation gap can be established between the stepped structure of the alveolar compartment and the basal surface of the artificial tooth supported or positioned on the protrusion. The effective gap spacing allows the gap space between the artificial tooth and the alveolar compartment to hold or contain a predictable, predetermined amount of bonding material. The effective gap spacing can also be established to avoid any dimensional imperfections / variations in the basal surface of the artificial tooth. For example, as shown in the cross-sectional views of Figures 6A and 6B, the height of the stepped structural projections (215a, 225a) in the alveolar compartment establishes a clearance spacing effective to avoid bulges or dimensional defects (335) in the base surface of the artificial tooth (300) supported or positioned on the projections. In preferred embodiments, the projection height may be at least about 25 microns and not more than about 500 microns. In more preferred embodiments, the projection height may be at least about 40 microns and not more than about 300 microns. In even more preferred embodiments, the projection height may be at least about 50 microns and not more than about 250 microns.

[0049] In another preferred embodiment, the width of the protrusions may be at least about 25 microns and not more than about 10 millimeters at their widest width. In a more preferred embodiment, the width of the protrusions may be at least about 40 microns and not more than about 8 millimeters at their widest width. In an even more preferred embodiment, the width of the protrusions may be at least about 50 microns and not more than about 7 millimeters.

[0050] In another preferred embodiment of the invention, at least two protrusions may protrude or extend outwardly from the lingual basal surface, and at least two protrusions may protrude or extend outwardly from the buccal basal surface. In embodiments in which at least two protrusions protrude from both the lingual and buccal basal surfaces, each of the protrusions on the lingual basal surface may be essentially equal in height to one another, and each of the protrusions on the buccal basal surface may be essentially equal in height to one another.

[0051] In a preferred embodiment, one or more projections may be (but need not be) substantially centered with respect to the bisection plane of the alveolar compartment, where the bisection plane of the alveolar compartment is essentially perpendicular from the mesial to distal direction of the alveolar compartment. In a further preferred embodiment where at least two projections are present on the lingual base surface, the projections may be located substantially equidistant from the bisection plane of the alveolar compartment (e.g., as shown by projections 215a and 215b in Figs. 4C and 4D). Similarly, when at least two projections are present on the buccal base surface, the projections may be (but need not be) located substantially equidistant from the bisection plane of the alveolar compartment (e.g., as shown by projections 225a and 225b in Figs. 4C and 4D). In an embodiment where at least two projections are present on the surface, they may be separated by a distance of at least about 25 microns and no more than about 8 millimeters, as measured from the circumference at the base of the projections. In more preferred embodiments where there are at least two protrusions on the surface, they may be separated by a distance of at least about 50 microns and no more than about 7 millimeters when measured from the perimeter at the base of the protrusions. In even more preferred embodiments where there are at least two protrusions on the surface, they may be separated by a distance of at least about 100 microns and no more than about 6 millimeters when measured from the perimeter at the base of the protrusions.

[0052] In preferred embodiments, the projections may occupy at least about 1% to no more than about 80% of the surface area at the lingual and / or buccal basal surfaces. In more preferred embodiments, the projections may occupy at least about 5% to no more than about 70% of the surface area at the lingual and / or buccal basal surfaces. In even more preferred embodiments, the projections may occupy at least about 10% to no more than about 50% of the surface area at the lingual and / or buccal basal surfaces.

[0053] One or more protrusions on the lingual base surface may be established to essentially match or replicate the same characteristics (e.g., shape, height, width, spacing) as those established on the buccal base surface. Alternatively, one or more protrusions on the lingual base surface may be established to be substantially different from those established on the buccal base surface. This may be advantageous to better meet patient-specific design needs for tooth position or alignment, provide greater efficiency or accuracy in the manufacture of the denture base, or provide a more favorable distribution or allocation of space that the bonding material occupies between the artificial teeth of the denture and the denture base for improved bond strength. For example, as shown in FIG. 6B, the height of the protrusions (215a) on the lingual base surface of the alveolar compartment is depicted as being greater than the height of the protrusions (225a) on the buccal base surface of the alveolar compartment.

[0054] Fabrication of denture base and teeth The dental arch forms and alveolar compartments may be formed in the denture base using any of a number of known methods and materials. The final size and shape of the denture base, including the dental arch forms and the alveolar compartments contained therein, is determined for the specific needs of the patient and may be determined from physical impressions or molds taken from the patient's intraoral jaw structure (upper and / or lower, depending on what is needed), intraoral imaging, extraoral imaging, or some combination thereof. The denture base may be formed from a variety of durable materials. Polymeric resin compositions are particularly suitable for forming denture substrates and are known to those skilled in the art. For denture bases made using CNC milling processes, a known approach is to use polymeric resin compositions that are hardened to a solid state in the shape of a disk or "puck." Such disks are provided with sufficient diameter and thickness to accommodate both the height and overall length of the patient's dental arch in order to cut the disks by a programmed CNC milling system. For denture bases made using a cast molding process, the uncured or partially cured polymeric resin composition (e.g., in a flowable, liquid or paste form) may be poured or pressed into a patient-specific pre-formed denture base mold. Alternatively, for denture bases made using an additive manufacturing (i.e., 3D printing) process, the uncured or partially cured polymeric resin composition may be placed into a suitably sized resin vat of a 3D printing device to form the patient-specific denture base layer-by-layer using a virtual design in a programmable, digitally controlled light-curing system, such as an SLA or DLP system.

[0055] Numerous dental adhesives or bonding materials are commercially available that are used to bond artificial teeth to printed or milled denture bases. They generally consist of acrylic monomers and / or prepolymers that are cured by either redox, heat or visible light polymerization techniques. In a typical case, at least one bonding material is applied to the alveolar compartment, to the tooth surface, or to both just prior to tooth insertion, the tooth is inserted into the alveolar compartment, and then heat and / or light is applied to complete the bonding process. The bonding material forms a bond between the tooth surface and the denture base. Tooth pretreatments can also be used in combination with the bonding material, where special bonding materials containing a combination of solvents and monomers swell the tooth surface. This can provide an additional surface adhesion layer and together increase the overall bond strength. The viscosity, shade and color of these adhesives or bonding materials can vary and can be selected or modified as necessary to suit a given material selection of the denture base and artificial teeth and / or other patient-specific needs.

[0056] Suitable preformed artificial tooth forms may be designed, fabricated and selected such that the size and shape of the base surface of each artificial tooth is configured to be received in at least one of the alveolar compartments of the present invention. A suitable artificial tooth form is one whose outer contour or shape profile and size correspond to the appropriate artificial tooth type (i.e., incisor, canine, bicuspid, molar) and / or tooth number (as used in the FDI International Dental Federation notation) associated with the natural oral anatomy and location along the dental arch. In one embodiment of the present invention, each artificial tooth may be bonded into the alveolar compartment by at least one bonding material, whereby the base surface of each artificial tooth is supported or placed on each protrusion in the alveolar compartment (see Figures 6A and 6B, which provide representative cross-sectional views for the placement of the artificial tooth on each protrusion), such that a predetermined amount of bonding material is maintained between the artificial tooth and the denture base. In this manner, dentures may be prepared with a more consistent and predictable adhesive layer interface and adhesive integrity established between each artificial tooth and the denture base.

[0057] The above-described embodiments of the present invention provide a number of different advantages, including better addressing the need for easier, more efficient and reliable arrangement of artificial teeth in a denture base, in addition to ensuring more consistent and predictable adhesion of the artificial teeth in the denture base, thereby making the denture making process more consistent and less labor intensive.

[0058] Establishing a convex stepped structure (200) in the alveolar compartment has been found to be advantageous for several reasons. First, by increasing or enlarging the area of ​​the alveolar compartment with a convex surface, a larger bonding surface becomes available for covering with a bonding material and supports a higher bond strength between the denture base and the artificial teeth. Furthermore, the convex structure helps to minimize the thinning and loss of dimensions of the denture base material in the concavely formed alveolar compartment. Such thinning can be detrimental and can result in distortion of the denture base, breakage or total destruction of the teeth due to a less robust physical construction. Furthermore, the stepped shape provides an efficient structural form that limits both the vertical and horizontal mechanical stresses encountered during use (e.g., shear / tear and compression / grinding forces during biting and chewing). This configuration further ensures stability and durability of the tooth position in the alveolus. Furthermore, the stepped shape facilitates the establishment of an initial, predetermined macroscopic support position or arrangement for the teeth within each alveolar compartment.

[0059] The transitional surface areas (230, 235, 240, 250) described above in relation to the lingual and buccal basal areas in the alveolar compartment may be advantageous in several ways. Among those advantages, these transitional surface areas may provide a less restrictive surface profile in the alveolar compartment, for example, in terms of manufacturing tolerances (either in subtractive processing tool tolerances or additive manufacturing printing resolution), and / or may further promote ease of fit against small contour variations that may be present at the base edges or corners of the artificial teeth. Additionally, these transitional surface areas may be included to provide a more favorable load-bearing or load-distributing configuration for the alveolar compartment, thereby reducing undesirable localized mechanical stress concentrations in the alveolar compartment that may cause premature weakening or failure of the denture base.

[0060] Further advantages can be realized by including a protrusion structure on the stepped structure surface in the alveolar compartment. In one notable aspect, the protrusions can provide additional micro-scale mounting surfaces in the alveolar compartment to further aid the technician in fine-tuning the placement and positioning of the teeth. Protrusions included on the tread-like lingual base surface can be established to help control the vertical tooth positioning independent of any protrusions included on the riser-like buccal base surface. Similarly, protrusions included on the riser-like buccal base surface can be established to help control the horizontal tooth positioning independent of any protrusions included on the tread-like lingual base surface. In this way, these independently established horizontal and vertical protrusion surface structures can be utilized to more easily achieve even more precise positioning, orientation and alignment of the artificial teeth within each of the alveolar compartments of the denture base. In a further aspect, the protrusions can provide an established control structure to ensure a predetermined gap distance or intermediate gap between the stepped surface of the alveolar compartment and the base surface of the tooth that is mounted or supported on the protrusions. By creating this predetermined gap spacing, the alveolar compartment can be made to better accommodate a diverse range of preformed artificial teeth. In this way, the alveolar compartment can be configured to better accommodate and equalize or compensate for various small surface imperfections on the base surface of the artificial teeth that would otherwise cause tooth instability (e.g., rocking or rotation) or maladjustment (e.g., tilt or imbalance). The protrusions may be configured as needed to best mitigate or accommodate surface imperfections / variations observed on the base surface of the artificial teeth (or perhaps other dimensional limitations observed when manufacturing the alveolar compartment), thus ensuring an easier, more efficient and reliable tooth arrangement process.

[0061] The number, size / dimensions, shape and spacing of the protrusions can be suitably selected and / or modified in advance by the technician when designing the denture base to suit the specific needs. For example, having each of the protrusions located substantially at the center of the surface and / or equidistant from the bisecting plane of the alveolar compartment can be particularly advantageous to ensure balanced, i.e. evenly distributed, physical support of the artificial tooth surface in the alveolar compartment. Also, having the protrusions separated by the preferred distances disclosed above can be particularly advantageous to ensure efficient flow, distribution or filling of the bonding material between or around the protrusions on the stepped structure. Furthermore, the predetermined gap spacing can ensure a controlled gap or separation between the base surface of the tooth and the alveolar compartment to establish a more consistent adhesive layer interface. Again, the number, size / dimensions, shape and spacing of the protrusions can be suitably selected and / or modified in advance by the technician when designing the denture base to suit the specific needs. The protrusions may be configured as needed to best achieve a desired volume and / or depth / thickness of bonding material occupying the interstitial space between the tooth surface and the alveolar surface. In this manner, a significant amount of technician-dependent variability in the bonding process can be reduced, allowing for a more predictable and reliable bond quality to be achieved.

[0062] However, it should be recognized that the present invention does not require any preferred or advantageous features, nor that all advantages need to be incorporated in all embodiments of the present invention. Although the present invention has been described in some detail with reference to certain preferred forms thereof, other forms are possible within the scope of the present invention. Thus, the spirit and scope of the appended claims should not be limited to the description of the preferred forms contained herein. Unless expressly stated otherwise, all features disclosed herein, including any of the appended claims, abstracts and drawings, may be replaced with other features serving the same, equivalent or similar purpose. Thus, unless expressly stated otherwise, each feature disclosed is merely one example of a generic series of equivalent or similar features.

Claims

1. Dental arch morphology, a plurality of alveolar compartments formed concavely within the dental arch form, one or more of the alveolar compartments including a convex surface, the convex surface having a stepped structure characterized by a tread-like lingual base surface and a riser-like buccal base surface such that the stepped structure projects from a lingual-facing side of the alveolar compartment toward a buccal-facing side of the alveolar compartment and substantially traverses the width of the alveolar compartment in a mesial-distal direction; one or more projections extending from locations on the stepped structure, the locations including: a) the lingual base surface of the stepped structure; b) the buccal base surface of the stepped structure; c) the lingual base surface of the stepped structure and the buccal base surface of the stepped structure; d) both the lingual and buccal base surfaces of the stepped structure, the projections extending in a continuous manner across at least a portion of both the lingual and buccal base surfaces; and e) A combination of these one or more protrusions selected from the group consisting of Including, the one or more protrusions are at least about 25 microns and no more than about 500 microns in height, and the one or more protrusions are at least about 25 microns and no more than about 10 millimeters in width at their widest point; A denture base for a denture, wherein at least two projections protrude from said lingual base surface and at least two projections protrude from said buccal base surface.

2. 2. The denture base of claim 1, wherein said lingual basal surface is substantially flat over its entire length, excluding said projections projecting from said lingual basal surface.

3. 2. The denture base of claim 1, wherein said buccal base surface is substantially convex across its width and substantially flat along its riser height, excluding said projections projecting from said buccal base surface.

4. 2. The denture base of claim 1, wherein said buccal base surface is substantially convex across its width and substantially convex along its riser height, excluding said projections projecting from said buccal base surface.

5. 2. The denture base of claim 1, wherein each of said projections on said lingual basal surface are essentially equal in height to each other, and each of said projections on said buccal basal surface are essentially equal in height to each other.

6. 6. The denture base of claim 5, wherein the projections on the lingual base surface and the projections on the buccal base surface are located substantially equidistant from the bisecting plane of the alveolar compartment, wherein the bisecting plane of the alveolar compartment is essentially perpendicular from the mesial to distal direction of the alveolar compartment.

7. 7. The denture base of claim 6, wherein said projections are separated by a distance of at least about 25 microns and no more than about 8 millimeters as measured from the periphery at the base of said projections.

8. (a) a denture base comprising: Dental arch morphology, a plurality of alveolar compartments formed concavely within the dental arch form, one or more of the alveolar compartments including a convex surface, the convex surface having a stepped structure characterized by a tread-like lingual base surface and a riser-like buccal base surface such that the stepped structure projects from a lingual-facing side of the alveolar compartment toward a buccal-facing side of the alveolar compartment and substantially traverses the width of the alveolar compartment in a mesial-distal direction; one or more projections extending from locations on the stepped structure, the locations including: i) the lingual basal surface of the stepped structure; ii) the buccal base surface of the stepped structure; iii) the lingual base surface of the stepped structure and the buccal base surface of the stepped structure; iv) both the lingual and buccal base surfaces of the stepped structure, the projections extending in a continuous manner across at least a portion of both the lingual and buccal base surfaces; and v) Combinations thereof one or more protrusions selected from the group consisting of wherein the one or more protrusions are at least about 25 microns and no more than about 500 microns in height, and the one or more protrusions are at least about 25 microns and no more than about 10 millimeters in width at their widest point; a denture base having at least two projections extending from said lingual base surface and at least two projections extending from said buccal base surface; (b) at least one bonding material; (c) a plurality of artificial teeth, each having a base surface sized and shaped to be received in at least one of said alveolar compartments and bonded within said alveolar compartments by said at least one bonding material, such that said base surface of each artificial tooth rests on a respective projection within said alveolar compartment, such that a predetermined amount of bonding material is maintained between said artificial tooth and said denture base; Dentures, including:

9. 9. The denture of claim 8, wherein said lingual basal surface is substantially flat along its entire length, excluding said projections projecting from said lingual basal surface.

10. 9. The denture of claim 8, wherein said buccal base surface is substantially convex across its width and substantially flat along its riser height, excluding said projections projecting from said buccal base surface.

11. 9. The denture of claim 8, wherein said buccal base surface is substantially convex across its width and substantially convex along its riser height, excluding said projections projecting from said buccal base surface.

12. 9. The denture of claim 8, wherein each of said projections on said lingual basal surface are essentially equal in height to one another and each of said projections on said buccal basal surface are essentially equal in height to one another.

13. 13. The denture of claim 12, wherein the projections on the lingual base surface and the projections on the buccal base surface are located substantially equidistant from a bisecting plane of the alveolar compartment, wherein the bisecting plane of the alveolar compartment is essentially perpendicular from a mesial to distal direction of the alveolar compartment.

14. 14. The denture of claim 13, wherein said projections are separated by a distance of at least about 25 microns and no more than about 8 millimeters as measured from the periphery at the base of said projections.

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