METHOD FOR SCALING A PORCELAIN MATERIAL LAYER OF A RESTORATION AND MACHINING PROCESS

Abstract

A method for scaling the porcelain material of a restoration and the associated machining process is invented, which comprises: establishing a data model of the restoration (S100); dividing the bonding surface or interface between veneer porcelain to be prepared and a restoration substrate into a finite number of element surfaces (S200); establishing the direction coordinate axis on every element surface as its reference axis for setting up a size and a thickness value of veneer porcelain of each element surface (S300); determining and specifying the size and thickness of the veneer porcelain of every element surface according to the preset size and thickness value, and completing the bonding surface by covering it with the veneer porcelain composed of all the element surfaces as scaled with those sizes and thickness values as referred to (S400); generating the outer contour of the veneer porcelain of a clinic restoration (S500).

Claims

1. A method for scaling a porcelain material layer of a restoration, characterized in that the method comprises: step S100, establishing a data model to represent a shape, size and position relationship of the restoration; step S200, dividing a bonding surface between a veneer porcelain layer and a restoration substrate into a limited number of element surfaces; step S300, establishing a direction coordinate axis on each element surface, which is used as a reference axis (5) to present a thickness value of the veneer porcelain layer for the individual element surface; step S400, determining and specifying, based on the reference axis (5), a thickness of the veneer porcelain layer of the individual element surface according to the set thickness value, and all porcelain elements and associated surfaces, which are scaled as referred to those set thickness values, cover the bonding surface; step S500, generating the outer surface of the veneer porcelain layer of the restoration, based on the scaled porcelain element surfaces.

2. The scaling method according to claim 1, wherein in the step S100, the restoration comprises crowns and a bridge, wherein the crown is a single crown or multiple crowns, the bridge is composed of bridge units (2), retainers (1) and connectors (3); or the restoration consists of bone parts of a human body to be repaired.

3. The scaling method according to claim 1, wherein in the step S100, the data model is a two-dimensional lone or a three-dimensional lone.

4. The scaling method according to claim 1, wherein in the step S200, for dividing the bonding surface into a limited number of element surfaces, the step S200 comprises: uniformly or non-uniformly dividing the bonding surface into a limited number of the element surfaces in line with each different position on the bonding surface; and performing a setup of a dense division or sparse division of the element surfaces in line with each different position on the bonding surface.

5. The scaling method according to claim 1, wherein in the step S200, a shape of the element surface is a rectangle, a hexagon, a diamond, or other self-closed shapes.

6. The scaling method according to claim 1, wherein in the step S300, the direction coordinate axis is established on each element surface and set perpendicular to the element surface individually, and each element surface is used as an independent scaling area; a scaling size of the veneer porcelain thickness in each scaling zone is set independently according to the factors such as the sintering conditions, the position of the scaling zone on the bonding surface and some other associated.

7. The scaling method according to claim 6, wherein in the step S400, in the case where a preset thickness value for every element surface is consistent, an outer profile of the veneer porcelain layer for a restoration is directly generated based on all the scaled element surfacess; in the case where the present thickness values are inconsistent, an inter-surface fitting among vicinal areas between every two adjacent element surfaces by utilizing a smooth algorithm, spline interpolation, gradient approach or weighted mean, for uneven connections throughout the element surfaces, such that a smooth curved interface between every two adjacent element surface is produced, and an outline surface of the veneer porcalain layer for the restoration is shaped up together with the scaling method and the smooth algorithm.

8. The scaling method according to claim 7, wherein in the step S400, the smooth algorithm to generate the fitting between every two adjacent element surfaces comprises: setting up at least one boundary line on an interface between each two adjacent element surfaces with a series of preset weight values, and with such a boundary line as the reference, setting up the constraint conditions for smooth fitting of the vicinal area among the associated element surfaces.

9. A machining process for a porcelain material layer of a restoration, characterized by comprising: step A100, designing and manufacturing a substrate frame of a restoration according to a object or clinic case to be applied to; step A200, according to design objectives, setting up and building up a layer of green porcelain on a top surface of the substrate frame in combination with the method for scaling a porcelain material layer of a restoration according to claim 1, calculating a strategy and parameters for an associated processing or machining according to the thickness and surfaces or surfaces computed precedingly on an outer contour of the green veneer porcelain to be processed or machined; step A300, placing the shaped green porcelain layer, together with its restoration substrate frame, into a heating furnace for sintering, and at the moment that the placing is completed, taking out the restoration and cooling it.

10. The machining process according to claim 9, wherein the step A200 of setting up and building up a layer of green porcelain material on the outer surface of the base frame, comprises: printing the green porcelain material onto the base frame by 3D printing technology; or piling up green porcelain material onto the base frame, performing a compacting treatment, and then milling it with a milling machine; or directly pressing the green porcelain material onto the base frame by using a mold with a designed contour shape to form an expected porcelain layer to be sintered.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0038] FIG. 1a is a schematic diagram of an outer contour of a zirconia substrate;

[0039] FIG. 1b is a schematic diagram of an outer contour of a veneer porcelain layer in the prior art enlarged uniformly and proportionally;

[0040] FIG. 2 is a schematic diagram of an outer contour of a veneer porcelain layer after the non-uniform enlargement using a center axis of the substrate as a reference axis;

[0041] FIG. 3 is a schematic diagram of dividing the surface of the repair unit into multiple scaling areas using the reference axis as a reference;

[0042] FIG. 4 is a schematic flowchart of a scaling method of the present invention;

[0043] FIG. 5 is a schematic flowchart of a manufacturing process of a dental all-ceramic restoration of the present invention.

[0044] Reference signs: 1-retainer; 2-bridge unit; 3-connector; 4-green porcelain material layer; 5-reference axis; 6-scaling area.

DESCRIPTION OF THE EMBODIMENTS

[0045] Before describing the embodiments of the present invention in detail, it should be noted that the veneer porcelain layer described in the present invention refers to a layer of porcelain material covering the surface of the restoration. For example, in the field of dentistry, it refers to a veneer porcelain on a substrate.

[0046] The present invention will be further described in detail below with reference to examples and drawings, but the embodiments of the present invention are not limited thereto.

[0047] For convenience of explanation, in this embodiment, a dental all-ceramic restoration is taken as an example for illustration. As shown in FIGS. 1a and 1b, in the prior art, an outer contour of a veneer porcelain that is enlarged uniformly and proportionally or enlarged independently according to the central axis of the substrate (zirconium substrate in dentistry), and there is a misaligning in the positional relationship between it and the substrate (see FIG. 1b, the positions on both sides of the zirconia base). In the production and machining files, such as milling, if the green porcelain material layer 4 is milled according to the above contour, it is very likely to damage the milling cutter or the zirconia substrate, causing unnecessary production losses. At the same time, the green porcelain material layer 4 to be sintered in later phase will shrink after sintering, causing the outer surface of the veneer porcelain on the substrate to be distorted, which is contrary to the design goal and affects quality and use effect of the dental all-ceramic restoration. The above-mentioned problems will also be encountered when setting the porcelain material layer on the surface of other restorations.

[0048] In view of the above problems, the present invention proposes a method for scaling a porcelain material layer of a restoration, as shown in FIG. 4, comprises: [0049] S100, establishing a data model for representing a shape, size and position relationship of the restoration; [0050] S200, dividing a bonding surface formed by a veneer porcelain layer and a restoration substrate into a limited number of element surfaces; [0051] S300, establishing a direction coordinate axis on each element surface as a reference axis 5 for setting a thickness value of the veneer porcelain layer of each element surface; [0052] S400, based on the reference axis 5, determining and setting the thickness of the veneer porcelain layer of each element surface according to the set thickness value, and wrapping the bonding surface through the veneer porcelain layer and its outer surface formed by scaling with the set thickness value as a reference; [0053] S500, based on the scaled element surfaces, generating the outer surface of the veneer porcelain layer of the dental restoration.

[0054] In the step S100, the restoration comprises a crown and a bridge, wherein the crown comprises a single crown or multiple crowns, and the bridge is composed of bridge unit 2, retainers 1 and connectors 3. In other embodiments, the restoration also comprises bone parts to be repaired by the human body, such as joint bones and head bones. The data model is a two-dimensional one or a three-dimensional one, and the above-mentioned data model accurately reflects the shape, size and position relationship of the restoration.

[0055] The establishment of the above data model needs to collect the situations of the to-be-repaired dental or bone parts of the application object, and then generate the corresponding data model according to the repair target. The way to collect the situations of the to-be-repaired dental or bone parts of the application object can be realized by three-dimensional scanning. In dentistry, it is possible to make the application object match a sampling block.

[0056] In detail, in the step S200, dividing the bonding surface into a limited number of element surfaces comprises: uniformly or non-uniformly dividing the bonding surface into a limited number of the element surfaces in line with each different position on the bonding surface; and performing a setup of a dense division or sparse division of the element surfaces in line with each different position on the bonding surface.

[0057] The element surfaces are divided in various forms, which can better meet the scaling requirements of the bonding surface. The above bonding surfaces are divided according to different reference factors, and the veneer porcelain layer outer surface scaled in the later phase can be better in line with the design goal. For example, on the top surface of the dental bridge unit 2, there are relatively many concave and convex surfaces, then the distribution density of the element surfaces is higher, and more accurate scaling is achieved. The side wall of the bridge unit 2 is smoother and may be used as element surfaces to be scaled at this time.

[0058] In the step S200, the shape of the element surface comprises a rectangle, a hexagon, a rhombus, or other self-closed shapes. And the above shapes are connected together to cover the bonding surface.

[0059] In order to simplify the calculation of the outer surface profile of the veneer porcelain layer in the later phase, in the step S300, the direction coordinate axis is established on each element surface, with the direction coordinate axis being set perpendicular to the element surface. Providing the reference axis 5 along a (normal) direction perpendicular to each element surface also matches the scaling path and orientation of the green porcelain material layer to be sintered and after being heated.

[0060] Further, in the step S400, if the set thickness value of the veneer porcelain layer of each element surface remains the same, the outer surface of the veneer porcelain layer of the restoration is directly generated according to the scaled element surfaces; if the set thickness value of the veneer porcelain layer of each element surface is inconsistent, a smooth curved surface generating algorithm is used to perform a curved surface fitting on the adjacent area between every two adjacent element surfaces to generate a smooth curved surface connecting the two adjacent element surfaces, and such scaled element surfaces and smooth curved surfaces are combined to generate the outer surface of the veneer porcelain layer of the restoration.

[0061] When the scaling sizes of the element surfaces are the same, after each element surface is scaled, every two adjacent element surfaces will be seamlessly connected to jointly form a veneer porcelain layer and a veneer porcelain layer outer surface on the above-mentioned bonding surface. When the scaling size of each element surface is inconsistent, stepped stripes or uneven warps will be formed on the generated veneer porcelain layer outer surface, and at this time, the smooth curved surface generation algorithm is used to smooth the connection surface of every two adjacent element surfaces, so as to ensure that the entire veneer porcelain layer outer surface generated in the later phase is smooth and meets the requirements of the occlusal relationship and aesthetics of the dental all-ceramic restoration.

[0062] In the step S400, a smooth curved surface generation algorithm comprises: at least one boundary line is set on an interface of two adjacent element surfaces of interest with a set weight value(s), and the boundary line is used as a reference to set a constraint condition for smooth fitting of the adjacent region of the boundary.

[0063] The above set weight value or values refer to the positional distance between the boundary line or interface line against two adjacent and connected element surfaces. For example, the closer it is, the higher the weight value. The above constraint condition refers to a relationship formed for between the generated smooth curved surface and the boundary line, such as intercrossing, tangent or the smooth curved surface covering the above boundary line, and so on; or, at a position near the connection of the edges of the two adjacent element surfaces, the scaling value is set as the average value of the scaling of two adjacent element surfaces.

[0064] The boundary line may be a straight line or a curve. Based on the above technical solution, the generation of a smooth curved surface is defined to ensure that the smoothness of the smooth curved surface satisfies the requirements of the veneer porcelain layer outer surface, and the smooth curved surface can be calculated mathematically, which is convenient for the generation of post-processing files.

[0065] Technically the key points of the scaling method of this invention are that: the bonding surface in the restoration in connection with the porcelain material layer is divided into a limited number of continuous or non-continuous element surfaces, and each element surface is used as an independent scaling zone 6; the scaling size and orientation of the thickness of the veneer porcelain layer in each scaling area 6 are independently set according to factors such as sintering conditions, the position of the scaling zone 6 on the bonding surface and so on, and the veneer porcelain layer contour calculated by the above scaling method can be, after sintering, closer to the design goal to meet the aligning or occlusal relationship during usage of the application object. Since the heat radiation received by each area of the restoration is different during the sintering process, the above settings also enable each scaling zone 6 to be better adapted to the above sintering environment, and the sintered veneer porcelain layer in the later phase does not need to be manually polished, which can significantly improve the processing and molding efficiency of the porcelain restoration and reduce the production cost.

[0066] Based on the above method for scaling a porcelain material layer of a restoration, the present invention also proposes a machining process for a porcelain material layer of a restoration, comprises: [0067] A100, designing and manufacturing a substrate of a restoration according to the situation of an application object; [0068] A200, according to the design goal, combined with the method for scaling a porcelain material layer of a restoration described above, providing a layer of green porcelain material to be sintered on the outer surface of the substrate, calculating and obtaining a curved surface of the veneer porcelain layer to be processed according to the outer surface of the veneer porcelain layer, and generating a corresponding machining strategy and parameters.

[0069] A300, the formed green porcelain material layer to be sintered along with the substrate of the restoration is placed in a heating environment and sintered, and subsequently taken out and cooled.

[0070] In the above technical solution, the green porcelain material layer to be sintered can meet the design goal after sintering and cooling, and ensure a normal aligning or occlusal relationship of the restoration in the later phase. Since the shrinkage properties of the veneer porcelain layer outer surface generated after sintering is fully considered in providing the green porcelain material layer to be sintered on the substrate surface, the veneer porcelain layer outer surface generated after sintering does not need to be manually polished, which can effectively improve the processing efficiency.

[0071] The step A200 of providing a layer of green porcelain material to be sintered on the outer surface of the substrate is achieved by one or more of the following manners: [0072] using a 3D printing technology to cover the green porcelain material layer to be sintered onto the substrate; or [0073] stacking the green porcelain material to be sintered onto the substrate, performing a compaction treatment, and using milling to generate the green porcelain material layer to be sintered; or [0074] directly pressing the green porcelain material to be sintered on the surface of the substrate by using a mold with a set shape to form the green porcelain material layer to be sintered; or [0075] other specific molding technology processing methods.

[0076] The above is only a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above-mentioned embodiments, and any technical solution that belongs to the idea of the present invention belongs to the scope of protection of the present invention. It should be noted that for those of ordinary skill in the art, several improvements and retouching without departing from the principles of the present invention should also be regarded as the scope of protection of the present invention.