Disk-Shaped Final-Strength Ceramic Blanks for Direct Dental CAD/CAM
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for producing ceramic dental prosthesis parts using unsintered disk-shaped blanks are limited, as they require additional processing steps like final sintering and are prone to mechanical failures due to one-sided attachment, leading to inaccuracies and high lever mechanics.
Innovation Solution
The use of a disk-shaped ceramic blank surrounded on its circumference in a mounting device, allowing machining with a grinding tool that rotates about its longitudinal axis for direct production of final-strength prosthesis parts, eliminating the need for sintering and reducing mechanical failures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If block-shaped blanks are used with one-sided attachment by block holder, then the attachment method is simple, but the mechanical lever is high leading to mechanical failures and inaccuracies
Solution Approach 1:
The blank shape is segmented from the traditional block form to a disk-shaped form with central through-hole, which fundamentally changes the attachment mechanics. The through-hole allows the blank to be mounted on a rotating axis, distributing mechanical stresses evenly and eliminating the high lever arm problems of one-sided block attachment.
Solution Approach 2:
The attachment method transitions from one-sided block holder attachment to circumferential mounting via the central through-hole. This dimensional change in mounting geometry eliminates the mechanical lever issues by allowing the blank to be securely attached at its center, distributing forces uniformly during rotation and machining.
2Ease of manufacture
If unsintered disk-shaped blanks are processed, then the blanks can be shaped, but additional processing steps like final sintering are required
Solution Approach 1:
The blank is pre-sintered to final strength before the CAD/CAM machining process, eliminating the need for post-machining sintering steps. This preliminary sintering action ensures the blank has sufficient mechanical properties for precise machining while eliminating subsequent thermal processing steps that would otherwise be required.
Solution Approach 2:
The sintering process is extracted and performed before machining rather than after. By taking out the sintering step from the post-machining sequence and performing it preliminarily, the workflow is optimized to allow direct machining of final-strength blanks, eliminating the need for tool changes and re-machining after sintering.
3Manufacturing precision
If final-strength blanks are machined, then the prosthesis parts achieve final dimensions, but traditional methods cannot process these blanks due to mechanical limitations
Solution Approach 1:
The blank is pre-sintered to final strength before machining, ensuring it has the mechanical properties needed for precise CAD/CAM processing. This preliminary strengthening action allows the blank to withstand the forces of precision machining while maintaining dimensional accuracy, something that unsintered or partially sintered blanks cannot achieve.
Solution Approach 2:
The manufacturing process is segmented into distinct phases: pre-sintering to final strength, then CAD/CAM machining. This segmentation allows each process to be optimized independently, with the pre-sintered blank providing the mechanical strength needed for precision machining without requiring post-processing sintering that would alter dimensions.
4Manufacturing precision
If disk-shaped blanks with central through-hole are used, then the blanks can be rotatably mounted for precise machining, but the blank geometry is more complex
Solution Approach 1:
The blank geometry transitions from a simple block shape to a disk-shaped form with central through-hole. This dimensional change in geometry enables rotatable mounting on a vertical axis, which is essential for precise CAD/CAM machining. The through-hole provides the mechanical interface for secure, centered mounting, eliminating the geometric limitations of block-shaped blanks.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method enables precise, high-quality production of ceramic dental prosthesis parts with improved geometric dimensions and surface roughness, eliminating errors from shrinkage and tool changes, suitable for both laboratory and chairside applications.
Implementation Method 1
machining the blank by way of the rotating grinding tool, proceeding from the initial contact
Data Source
AI summary
The invention relates to a method for producing ceramic dental prosthesis parts by way of a CAD/CAM machining station, comprising the following steps that is capable of providing a disk-shaped ceramic blank, wherein the blank has the final strength; attaching the blank in a mounting device of the CAD/CAM machining station; controlling the CAD/CAM machining station for establishing an initial contact between the blank and the grinding tool in such a way that, due to the rotation of the grinding tool about the longitudinal axis thereof, the entire contact surface between the grinding tool and the blank has relative movement; and machining the blank by way of the rotating grinding tool, proceeding from the initial contact, to produce the ceramic dental prosthesis parts.